JP6536884B2 - Modification method of metal surface using micro and nano bubble and adhesion method of metal and resin - Google Patents

Description

  The present invention relates to a method for modifying a metal surface with a processing solution containing micro-nano bubbles of ozone having strong oxidizing power, and to improve adhesion between a metal and a resin surface-modified by the modifying method. Related to the bonding method.

  Since ozone has strong oxidizing power, it has been conventionally used for sterilization and the like. It is also known that exposure of metal materials and resin materials to ozone promotes corrosion and deterioration. In recent years, it has been studied to use ozone gas and ozone water for the purpose of surface modification of resins and metals, focusing on the high oxidizing power of ozone.

  For example, in the method of manufacturing a photosensitive drum unit, the adhesion between the fitting portion of the end member attached to the end of the photosensitive drum and formed of a material containing a crystalline resin and the aluminum base of the photosensitive drum is enhanced. Therefore, a method has been proposed in which the resin outer surface portion of the fitting portion is oxidized by exposure to ozone or immersion in ozone water (see Patent Document 1).

  Further, in Patent Document 2, in the manufacturing process of the quartz crystal device, the Au layer of the Au / Cr corrosion-resistant film formed on the substrate before resist application is subjected to surface reforming treatment with ozone water for a short time. Methods have been proposed to improve the adhesion of the resist. In this reforming method, the contact angle improvement effect can be obtained by contacting with ozone water of 50 ° C. or more containing carbon dioxide having an ozone concentration of 100 ppm or more.

  Furthermore, instead of using the above-mentioned ozone gas or ozone water, the surface of the resin is reformed using a treatment liquid containing micro-nano level microbubble ozone, and the adhesion strength required when metal plating the resin is improved. Alternatively, attempts have been made to impart dyeability to resins. For example, in Non-Patent Document 1, in the metallization of ABS resin using ozone micro / nano bubble water, low concentration ozone gas is dissolved in water, nano bubble of ozone gas is used in water, and the nano bubble is long and stable. A method of effectively reforming the surface of an ABS resin by utilizing it as an ozone supply source has been proposed.

  As in the case of the above-mentioned resin, oxidation by a treatment solution containing micro-nano bubbles of ozone is also considered in the surface modification method of metal. The inventors of the present invention have already reported in Patent Document 3 that the metal surface is washed and oxidized with ozone micro / nano bubbles, resin is directly injection-formed, and metal and resin are firmly integrated or oxidized metal And resin can be firmly adhered using an adhesive.

  As described in Non-Patent Document 2, micro / nano bubbles are (a) small in bubble diameter, (b) slow in rising speed, (c) reducing frictional resistance, (d)) bubbles High internal pressure, (e) large gas-liquid interface, (f) large amount of dissolved gas, (g) accompanied by dissolution and contraction, and (h) negatively charged surface of bubble Since it has various characteristics such as being, it is expected that it will be applied to a wide range of fields such as food, cosmetics, medicines, semiconductor cleaning, plant cultivation and the like utilizing these characteristics. Since the micro and nano bubbles have a very small buoyancy compared to the viscous force as the particle size becomes smaller, they can stay in the liquid as superfine bubbles for a long time without floating on the upper surface, and the sphere diameter of the bubbles is very large. It is known that a liquid containing nanobubbles can not be visually confirmed and becomes colorless and transparent.

  In order to generate micro-nano bubbles, there are roughly divided into a method of entraining a gas by fluidizing the liquid and a method of blowing the gas in a stationary state. Specifically, as described in Non-Patent Document 2, various micro / nano bubble generation methods are proposed by a swirling liquid flow type, static mixer type, Bencher type, pressure dissolution type, pore type, etc. It is done.

  As described above, since the micro / nano bubble has an unconventional feature, the cleaning for removing the resist film which has already adhered to the substrate such as the glass substrate or the semiconductor wafer or removing the contaminant such as metal or metal compound Application is considered as a method (for example, refer to patent documents 4). The invention described in Patent Document 4 is a cleaning method for cleaning electronic / mechanical parts using ozone water generated without addition by gas-liquid mixing method, wherein the particle size R of ozone bubbles contained in the ozone water is 0 < Since R ≦ 1000 nm, the rise of the ozone bubble is suppressed, and it is possible to obtain a sufficient cleaning effect without degassing easily.

JP, 2014-29462, A JP 2012-107270 A JP, 2013-166143, A JP, 2008-192630, A

Origami Yuri, Yokota Atsuko, Tashiro Yoshihiko, Umeda Yasushi, Honma Hideo, Takai Osamu, “ABS Metallization with Ozone Micro / Nano Bubble Water”, Surface Technology, 2013, Vol. 64, No. 12, pp. 687-688 Hideki Tsuge, "Basics of micro bubbles and nano bubbles", Bull. Soc. Sea Water Sci. , Jpn. 2010, 64, pp. 4-10

  Applying an oxidation treatment with ozone gas or ozone water to reform the metal surface is more difficult to activate the surface than in the case of a resin, so treatment is performed in a system close to sealing to increase the oxidizing power. Conventionally, methods such as increasing the concentration of ozone or raising the temperature of ozone gas or ozone water have been used. In addition, other additive components such as carbon dioxide and hydrogen peroxide may be added. Although the surface modification example of Au as a metal is described in the said patent document 2, the adhesiveness with resin is improved also in the case of metal surfaces, such as not only Au but general copper, aluminum, iron, etc. As mentioned above, it is necessary to perform ozone treatment under very severe conditions to obtain sufficient effect.

  On the other hand, treatment solutions containing micro-nano bubbles of ozone have been studied to suppress the problem that ozone diffuses into the atmosphere, but the ozone concentration in the treatment solution is lower than ozone gas or ozone water, Mostly applied for surface modification of resin for the purpose of oxidation under mild conditions. However, in the case of microbubbles of submicron or more, the particle size of the bubbles increases in a short time, it is difficult to exist for a long time in a micro level state, and it is difficult to maintain sufficient oxidizing power. Furthermore, at high temperatures above room temperature, the disappearance of microbubbles is accelerated and ozone diffuses into the atmosphere in a short time, so it is extremely difficult to exert a sustained and stable oxidizing power during metal surface treatment. Therefore, as disclosed in Patent Documents 3 and 4, the surface treatment method of metal with a treatment liquid containing nanobubbles finer than microbubbles was studied.

  However, Patent Document 3 only proposes a method and apparatus for generating nanobubbles, and a method of surface treatment of metal by micro-nanobubble treatment of ozone, which is performed to improve adhesion with a resin. There is no specific disclosure of the treatment conditions and the like. It merely presents the possibility of technology that a processing solution containing micro-nano bubbles of ozone may be used as one of metal surface processing methods.

  Further, the invention described in Patent Document 4 utilizes the well-known technology that the rise of nanobubbles (nanobubbles) of ozone is suppressed for the cleaning method of electronic and mechanical parts, and adhesion of metal and resin There is neither description nor suggestion about the idea of actively modifying the surface of a metal with a processing solution containing ozone micro-nano bubbles in order to improve the power. Further, the ozone water containing ozone nanobubbles described in Patent Document 4 has an ozone concentration of 20 ppm or less, and the effect of reforming the metal surface is sufficient such that the adhesion to the resin is improved by the ozone water. It was totally unclear whether it could be obtained or not.

  In addition, well-known documents on micro / nano bubbles including the patent document 2 disclose that the micro / nano bubbles are positively used for the purpose of surface modification of metal to improve adhesion with resin. There is no specific description or suggestion on the surface modification method of metal by ozone micro / nano bubble processing, processing conditions, etc. Thus, the technical idea of utilizing micro-nano bubbles of ozone for surface modification of metals has not been well recognized in the art.

  Therefore, as in the case of the resin surface modification method, efficient surface modification is performed in a short time using a processing solution containing fine ozone micro / nano bubbles even in metal, and adhesion between metal and resin is It is highly desirable to establish an effective method of metal surface modification to improve and a method of bonding both. If they can be established, parts and components made of metals and resins used in various fields such as household appliances such as electric and electronic parts, industrial instruments such as automobiles and machine tools, and public appliances such as railways and power generation We can expect expansion of application to equipment and new development.

  The present invention has been made in view of the above-described conventional problems, and has ozone concentration higher than that of the prior art, and further, ozone / nano bubble of ozone whose average particle diameter is optimized at nano level The synergetic effect of the ozone oxidizing power is obtained by using the treatment solution contained, and the method of modifying the metal surface which reforms the metal surface by utilizing the effect is carried out, and the surface modification is carried out in this way It is an object of the present invention to provide a method of bonding metal and resin with a metal and a resin whose adhesion is higher than that of the conventional method and the variation of the adhesion can be extremely reduced by bonding the metal to the resin.

  In the present invention, the ozone concentration of the processing liquid for performing the surface modification of the metal is improved in order to greatly improve the adhesion to the resin by efficiently and effectively performing the surface modification of the metal by the oxidation of ozone. The average particle size of micro-nano bubbles of ozone contained in the treatment liquid is made finer at the nano level as a method of maintaining high concentration ozone inside and suppressing ozone diffusion into the atmosphere while increasing it more than before and suppressing ozone diffusion into the atmosphere. The present invention has been made by finding that the above problems can be solved by reducing the size to the range.

That is, the constitution of the present invention is as follows.
[1] The present invention is a method of reforming a metal surface by a treatment liquid having gas micro / nano bubbles, wherein the gas contains ozone, and the concentration of dissolved ozone in the treatment liquid is at room temperature (10 to 25). ° C.) and at 30ppm or more when measured by, and the average particle size and density of the micro-nano bubbles of gas contained in the treatment liquid is, when measured by cryo transmission electron microscopy by Koritsutsumiuma method, respectively Provided is a method of modifying a metal surface using micro / nano bubbles characterized in having a size of 30 nm or less and 10 ⁸ or more per ml .
[2] The present invention, the processing liquid containing micro-nano bubbles of the gas, a solution containing 200~15000ppm ozone as dissolved gas, through the through eyelet from the outside of the tube having two or more through eyelet circumferentially When the jet is performed at a pressure higher than the atmospheric pressure, the cylinder is provided with the dissolved liquid jetted from the respective openings of the two or more small through holes disposed opposite to each other on the same plane parallel to the radial cross section of the cylinder. [4] is a treatment liquid having gas micro / nano bubbles generated by collision so that a water hammer is concentrated at the center of the center, and the modification of the metal surface using the micro / nano bubbles according to the above [1] Provide quality methods.
[ 3 ] The present invention is that the gas is a gas containing at least one of carbon dioxide, hydrogen peroxide and oxygen in addition to ozone, and the treatment liquid is pure water containing the micro / nano bubbles. A method of modifying a metal surface using the micro / nano bubbles according to the above [1] or [2] , characterized in that
[ 4 ] The present invention is the metal utilizing the micro / nano bubbles according to any one of the above [1] to [ 3 ], wherein the temperature of the treatment liquid having the micro / nano bubbles of the gas is 30 ° C. or higher. Provided is a method of surface modification.
[ 5 ] The method of the present invention is a method of modifying a metal surface using micro / nano bubbles according to the above-mentioned [ 4 ], wherein the temperature of the treatment liquid having the gas micro / nano bubbles is 50 to 90 ° C. I will provide a.
[ 6 ] The present invention provides a method of modifying a metal surface utilizing micro / nano bubbles, which comprises immersing the metal in the treatment liquid according to any one of the above [1] to [ 5 ].
[ 7 ] The present invention provides the method of modifying a metal surface using micro / nano bubbles according to the above-mentioned [ 6 ], wherein the time for which the metal is immersed in the treatment liquid is within 100 minutes. .
[ 8 ] The present invention provides a method of modifying a metal surface utilizing micro / nano bubbles, characterized in that the treatment liquid according to any one of the above [1] to [ 5 ] is sprayed onto the metal.
[ 9 ] The present invention is the modification of the metal surface utilizing micro / nano bubbles characterized in that the treatment liquid according to any one of the above [1] to [ 3 ] is sprayed on the metal heated to 30 to 250 ° C. Provide a way.
[ 10 ] The present invention, in the step of spraying the treatment liquid onto a metal, the spraying time is within 30 minutes, and the metal surface using the micro / nano bubbles according to the above [8] or [9] Provide a method of reforming the
[ 11 ] The present invention includes the step of drying the metal whose surface is modified by the modification method according to any one of the above [1] to [ 10 ]. Provided is a method of surface modification.
[ 12 ] The present invention relates to a metal whose surface is modified by the modification method described in the above-mentioned [ 11 ] and a resin by any of potting, injection molding, transfer molding and pressure bonding at room temperature or under heating. A method of bonding metal and resin comprising the step of bonding, and the step of heating the metal after bonding for a predetermined time or leaving it at room temperature for a predetermined time in order to improve the adhesion between the metal and the resin. I will provide a.
[ 13 ] The present invention provides a method for bonding metal and resin, comprising the step of bonding the metal whose surface has been modified by the modification method described in the above [ 11 ] to a resin with a resin adhesive.
[ 14 ] The present invention relates to a metal whose surface is modified by the modification method according to the above [ 11 ], a metal whose surface is modified by a resin adhesive, or a metal whose surface is modified Provided is a method of bonding metal and resin, comprising the step of bonding with another metal.
[Effect of the invention]

  The method for modifying a metal surface according to the present invention can efficiently and effectively perform surface modification because it uses a treatment solution containing high concentration of ozone and simultaneously containing micro-nano bubbles of ozone. it can. Furthermore, by increasing the density of the micro / nano bubbles of ozone contained in the treatment liquid, the frequency of the micro / nano bubbles coming into contact with the metal surface is increased, so that the oxidation reaction can be promoted and the modification effect can be improved. Moreover, the modification method of the present invention can not only be conveniently performed by spraying the treatment liquid or immersing in the treatment liquid, but also can shorten the treatment time.

  The micro-nano bubbles of ozone used in the present invention are highly effective in suppressing the diffusion of ozone in the atmosphere while containing ozone of high concentration, as compared with conventional ozone gas and ozone water. Therefore, metal surface treatment can be performed more efficiently and reliably than the conventional method while reducing the load on the environment. In particular, the spread of ozone that occurs in a short time when ozone treatment is performed at a high temperature above room temperature can be largely controlled, so the load on the environment can be reduced, the safety of the work environment can be improved, or the incidental done for maintenance of the work environment. The installation of equipment can be simplified.

  The surface-modified metal according to the present invention has high adhesion to the resin and can reduce variation in adhesion between lots. Furthermore, the adhesion between metal and resin can be made simply by utilizing a conventionally established adhesion method without employing a particularly difficult method or process. Therefore, not only the adhesion between the metal and the resin can be increased but also the manufacturing cost can be simultaneously reduced.

It is sectional drawing which shows typically the representative example of the modification method of the metal surface by this invention. It is the front view and perspective view which show the micro * nano bubble generator used by the modification method of the metal surface shown in FIG. In the micro-nano bubble generating apparatus shown in FIG. 2, it is a figure which shows the example of the nozzle shape which generate | occur | produces the micro micro-nano bubble of gas, and the nozzle header which injects a process liquid, respectively. It is a figure which shows one shape of the liquid collision nozzle 26 shown in FIG. It is a front view which shows an example of the micro / nano bubble generator used by the spraying system of a process liquid in the modification method of the metal surface of this invention. It is a front view which shows the modification of the micro * nano bubble generator used by the spraying system of a process liquid in the modification method of the metal surface of this invention. It is a figure which shows the particle size distribution of the nano bubble of the photograph of the electron microscope image of those amorphous ice about the air nano bubble water of the reference example 1, and the water which does not contain a nano bubble. FIG. 1 is a photograph of an electron microscopic image of amorphous ice and the particle size distribution of nanobubbles of the ozone nanobubble water of Example 1. FIG. It is a figure which shows the evaluation method of the adhesive force performed in the Example of this invention. It is a figure which shows the abundance of the SEM photograph of Cu board surface before resin adhesion which showed the highest adhesive strength in Example 2 of the present invention, and each element, respectively.

  The treatment liquid used in the method of modifying a metal surface according to the present invention needs to have an ozone concentration higher than that of the prior art in order to maintain the necessary oxidizing power to activate the metal surface to perform surface modification. . The state of high concentration ozone in the treatment solution can be maintained to some extent by storing it in a closed container etc. However, when metal surface modification treatment is carried out, the treatment solution is released and ozone is diffused by large diffusion into the atmosphere. The concentration drops sharply. Therefore, although the oxidation by ozone can be expected at the initial stage of the treatment, the oxidizing power of the treating solution is rapidly reduced in a short time, and the oxidizing power is lost while the metal surface is not sufficiently reformed. This phenomenon is remarkable when the surface modification of metal is performed at a high temperature of 30 ° C. or higher. In principle, the surface modification at high temperature using the treatment solution should have a higher reforming effect, but in the case of metal, the diffusion of ozone into the atmosphere before the surface is activated. Is promoted. In the initial stage of the reforming treatment, the oxidizing power of ozone contained in the treatment solution in contact with the metal surface is obtained, but the effect of surface modification can not be obtained due to the rapid decrease of the ozone concentration in a short time, Even if the treatment is continued, the surface modification of the metal can not be continued.

  Therefore, in the present invention, based on the above-mentioned technical problems, not only the ozone concentration in the treatment liquid is simply increased, but as a method of maintaining the ozone concentration contained in the treatment liquid for a long period of time or longer, Attention was focused on a processing solution containing micro-nano bubbles containing ozone. That is, in the present invention, both high concentration ozone dissolved in the treatment liquid and ozone which is contained in the micro / nano bubbles and continuously and stably exist as compared with the ozone water are used synergistically. Furthermore, in order to extend the life of ozone contained in the micro / nano bubbles, the present invention is characterized in defining the average particle diameter of the micro / nano bubbles in a direction closer to the fine range than the nano level.

  The processing solution used in the present invention has a dissolved ozone concentration of 30 ppm or more when measured at room temperature (10 to 25 ° C.) by a dissolved ozone densitometer. The concentration of ozone dissolved in the treatment solution does not differ significantly at room temperature of 10 to 25 ° C, but it is measured at a high value at low temperatures and a low value at high temperatures due to the difference in the solubility of ozone in water. There is a tendency. In the present invention, the ozone concentration contained at the temperature at which the treatment is actually carried out using the treatment liquid has a significant meaning in achieving the effects of the present invention, but the dissolved ozone concentration in the treatment liquid is And in order to compare simply, it is practical to define the value which can be stably measured at room temperature (10-25 ° C) as a standard which knows dissolved ozone concentration. If the ozone concentration measured at room temperature is less than 30 ppm, not only the ozone used for the treatment is insufficient at the initial stage of the surface modification of the metal, but also the ozone concentration remaining during the treatment greatly decreases. The quality effect has almost no effect.

  On the other hand, in order to improve the surface modification effect of the metal, the higher the concentration of ozone dissolved in the processing solution, the better. However, since ozone is extremely diffused into the atmosphere, it is difficult to produce a processing solution having a stable ozone concentration when the ozone concentration exceeds 200 ppm or more. Therefore, the treatment liquid used in the present invention can hold ozone contained in the treatment liquid at a high concentration by including both ozone dissolved in the treatment liquid and ozone contained as micro / nano bubbles. Therefore, effective surface modification is possible for metals.

  In the present invention, it has been found that the ozone concentration contained in the treatment liquid can be maintained for a long period of time or more by defining the specific average particle diameter of the micro-nano bubbles containing ozone to 100 nm or less, preferably 30 nm or less. The By defining the average particle diameter of the micro / nano bubbles containing ozone within the above range, the oxidizing power of ozone can be maintained even when the modification processing operation of the metal surface is performed at high temperature, and a sufficient surface modification effect can be obtained. Be When the average particle size of the micro-nano bubbles containing ozone exceeds 100 μm, there is almost no effect of suppressing the diffusion of ozone into the atmosphere, and even if the concentration of ozone in the treatment liquid is high, the metal surface modification effect is I can not get it. Furthermore, by defining the average particle diameter of the micro / nano bubbles to 30 μm or less, the diffusion of ozone can be suppressed even at a high temperature of 30 ° C. or more, so metal surface modification can be performed in a shorter time and more reliably. Can. And in the adhesion with the resin, the metal whose surface is modified by the treatment liquid of the present invention has high adhesion, and stable adhesion with little variation in adhesion can be obtained.

  The amount of gas micro / nano bubbles generated depends on the amount of dissolved gas contained in the treatment liquid for cleaning, and the solubility constant of the gas in the liquid decreases as the temperature of the treatment liquid increases, so the amount of dissolved ozone It is technical common sense in the field that there is a tendency to decrease Therefore, when gas micro / nano bubbles are used at high temperature, it is considered to be likely to cause a decrease in the surface modification effect of the metal, and it has not been practiced until now. On the other hand, as a result of examining in detail the properties and characteristics of micro / nano bubbles and treatment methods suitable for surface modification of metals, the present invention is not confined to the conventional general common sense. By using a treatment liquid having nanobubbles having a particle size as small as 100 nm or less, preferably 30 nm or less, surface modification of metals, which was difficult by the conventional method, can be performed efficiently and in a shorter time. It was made by finding out what can be done.

In the present invention, it is further preferable that the density of the micro / nano bubbles containing ozone is 10 ⁸ or more per 1 ml (milliliter) of the treatment liquid. In the present invention, since the micro-nano bubbles containing ozone have a very small average particle diameter of 100 nm, preferably 30 nm or less, their density is increased by the conventional method in order to increase the concentration of ozone contained in the micro-nano bubbles. It needs to be higher than micro-nano bubbles manufactured. In addition, in the surface modification of metal, since the micro / nano bubbles are considered to be progressed by the oxidation reaction caused by contact with the metal surface, the frequency in the contact with the metal surface and the number of oxidation reaction contacts are increased. It is desirable that the density of the micro / nano bubbles be high. Therefore, when the density of the micro / nano bubbles is 10 ⁸ or more, the ozone in the bubbles can be maintained at a high concentration, and furthermore, the reactive contact with the metal surface can be sufficiently secured, so the surface modification of the metal It can be done in a short time and reliably. In the present invention, the density of micro / nano bubbles containing ozone is preferably 10 ⁸ or more, more preferably 10 ¹² / ml or more, particularly preferably 10 ¹⁶ / ml, per 1 ml (liter) of the treatment solution. It is above. By setting the density of the micro / nano bubbles to 10 ¹² cells / ml or more, and further 10 ¹⁶ cells / ml or more, the processing time for surface modification of metal can be significantly shortened.

  The micro-nano bubbles of ozone contained in the treatment liquid used in the present invention tend to have a larger amount of bubbles contained at the nano level and a smaller amount of micro-order bubbles as the average particle diameter is smaller. The size of the micro / nano bubble is also affected by the particle size distribution (standard deviation of particle size), but the effect is small, and the micro / nano bubble contained in the treatment liquid has an average particle size on the order of nano level, It is necessary to have an average particle size as small as possible. In the present invention, micro-nano bubbles containing ozone can be measured by a cryotransmission electron microscope by an ice embedding method.

  Various methods are conventionally known as methods of measuring the particle size of micro / nano bubbles. Among them, since the measurement method of nanobubbles is difficult to optically observe, for example, a light scattering method using Mie scattered light, a laser diffraction / scattering method, and Brownian motion of bubble particles in liquid are observed. A nanoparticle tracking analysis method, a pore electrical resistance method (Cole-counter method), a dynamic light scattering method, a resonance type mass measurement method using a beam of MEMS (Micro Electro-Mechanical Systems), and the like have been proposed. Besides these methods, a method of determining the particle diameter of nanobubbles by zeta potential measurement and a method of confirming the presence of nanobubbles by electron spon resonance (ESR) using a spin trapping agent have been proposed.

  The present invention etc. propose a method of measuring with a cryo transmission electron microscope by ice embedding method as micro / nano bubble measurement methods other than the above (see Japanese Patent Application No. 2014-230407). This method is contained in a liquid by making the liquid into an amorphous solid state and observing the ultrafine bubbles contained in the liquid in the amorphous solid state using a transmission electron microscope. The hyperfine bubbles and their distribution can be directly observed and analyzed as an image. Therefore, ultrafine bubbles having a particle size of less than 10 μm can be measured with high accuracy. The average particle diameter of the gas micro-nano bubbles specified in the present invention is determined by measurement using this method.

The method of measuring with a cryo-transmission electron microscope by ice embedding method uses a liquid held on a micro grid or a micro mesh as a sample and observes it by a transmission electron microscope with an energy of 10 to 300 kiloelectron volts (keV). The measurement is performed by setting the number of electron beams used sometimes to 1 to 10 ⁵ electrons / Å ² .

  The density of the micro-nano bubbles containing ozone can be measured by cryo-transmission electron microscopy by an ice embedding method, as with the average particle size. In the observation image measured by the cryo-transmission electron microscope, the micro / nano bubbles appear as dark particles in a light and dark portion, and the portion is subjected to an image analysis process by a known method such as a typical binarization process. It can be determined as the density per 1 ml of treatment solution.

  As a combination of gas micro / nano bubbles and a treatment liquid used in the present invention, it is preferable that the gas is at least ozone, and further contains at least one of carbon dioxide, hydrogen peroxide and oxygen. The treatment liquid is preferably pure water containing micro / nano bubbles containing the gas. The combination of the gas containing at least ozone and pure water can not only obtain a high effect on the surface modification of metals, but also the above-mentioned various gases are stably present in water for a long time, so storage and preservation It is easy and excellent in safety, and can reduce the load on the environment.

  For example, when ozone and carbon dioxide are contained as the gas, more efficient surface modification can be performed by the induction of ozone by the adsorption power of carbon dioxide on the metal surface and the acidification action of carbon dioxide. Moreover, when ozone and hydrogen peroxide are contained, hydroxyl radical (OH.) May be generated by the reaction of ozone and hydrogen peroxide, and the strong oxidizing power of this hydroxyl radical can be utilized. On the other hand, when ozone and oxygen are contained, metal surface modification can be performed while reducing the load on the environment. In the present invention, it is essential to contain ozone as the gas, but other gases may be used alone or in combination of two or more.

  The treatment liquid used in the present invention is preferably heated or heated to 30 ° C. or higher, preferably 50 to 90 ° C., in order to accelerate the oxidation of the metal surface by ozone. As described above, in the present invention, the diffusion of ozone into the atmosphere can be suppressed even at a high temperature of 30 ° C. or more by defining the average particle diameter of the micro / nano bubbles to 100 μm or less, preferably 30 μm or less. On the other hand, in order to reduce the load on the environment, it is preferable to use pure water as the treatment liquid, but in that case, the temperature that can be heated or heated is limited to less than 100 ° C. Therefore, the treatment solution has a temperature of 30 from the viewpoint of metal surface modification effects, sample handling during the cleaning process, temperature control, cleaning device capacity and durability, energy saving, environmental impact, and safety. By optimizing the temperature within the range of 50 ° C. or more, preferably 50 ° C. to 90 ° C., it is possible to shorten the time and improve the time of the modification treatment of the metal surface. . When the temperature of the treatment liquid exceeds 90 ° C., the diffusion of ozone into the atmosphere can not be suppressed even if the average particle size of the micro-nano bubbles containing ozone is 30 nm or less, and the metal surface reforming effect The decrease is remarkable, and the effects of the present invention can not be sufficiently obtained. In addition, if the temperature of the processing solution exceeds 90 ° C., it becomes difficult to control the temperature. Thus, when the temperature of the treatment liquid is set in the range of 50 to 90 ° C., a high surface modification effect can be stably obtained.

  In the present invention, the temperature of the treatment liquid is not only increased by heating or heating to 30 ° C. or higher, preferably 50 to 90 ° C., and ultrasonic vibration, ultraviolet irradiation or vacuum is applied to the substrate to be cleaned. A method of simultaneously applying ultraviolet light can be employed. Although the detailed mechanism is unknown, ultrasonic vibration helps uniform collapse of micro / nano bubbles having an average particle size of 100 nm or less contained in the treatment solution and promotes release of ozone present in the micro / nano bubbles. It is thought that it may have a function. The release of ozone in the micro / nano bubble can be realized uniformly and in a minute space or minute gap by applying ultrasonic vibration, which may greatly contribute to the modification of the metal surface. If the vibration frequency when applying the ultrasonic vibration is 10 kHz to 3 MHz, the effects of the present invention can be sufficiently achieved. On the other hand, ultraviolet irradiation or vacuum ultraviolet light irradiation has the advantage that the modification time of the metal surface can be shortened since it works to support oxidation by ozone.

  Next, a method of modifying a metal surface performed using a processing solution having micro / nano bubbles containing ozone will be described using the drawings.

  FIG. 1 is a cross-sectional view schematically showing a representative example of the method for modifying a metal surface according to the present invention. In FIG. 1, (a) and (b) are surface modification methods performed by immersing a metal for modifying the surface in a treatment solution having micro-nano bubbles of ozone, (c) and (d) 2.) is a surface modification method performed by spraying a processing solution having micro / nano bubbles containing ozone onto metal for modifying the surface.

  In (a) of FIG. 1, six of the metal plates 1 are supported within the container 3 containing the processing solution 2 having micro / nano bubbles containing ozone having an average particle diameter of 100 nm or less, preferably 30 nm or less. After placing the container 3 in a fixed state using the thin wire 5 in the mount 4 and sealing the container 3 with the lid 6 of the container, the metal is reformed by immersion for a predetermined time. Here, the temperature of the processing solution 2 is monitored and controlled by the heater 7 and the temperature measuring means 8 such as a thermometer or thermocouple and the stirrer 9. The heater 7 and the temperature measuring means 8 are connected to a temperature controller (not shown), and the temperature controller automatically controls the temperature. If necessary, the temperature of the treatment liquid 2 can be heated or heated to a temperature of 30 ° C. or higher. Further, since the concentration of ozone dissolved in the treatment liquid 3 is measured at the treatment temperature during the reforming process, the measurement unit of the dissolved ozone concentration sensor 10 is inserted into the inside of the treatment liquid 3. The dissolved ozone concentration sensor 10 needs to be measured at room temperature in order to compare the dissolved ozone concentration of each processing solution, and is put in a removable state so that movement is easy so that it can be used also at that time. Furthermore, the container lid 6 may be provided with a fine through hole for the purpose of degassing when any gas is generated inside the container 3. In addition, although the example which surface-reforms about six sheets of the metal plate 1 is shown in (a) of FIG. 1, the number of process sheets of metal can be selected arbitrarily in this invention. In addition, the shape and size of the metal or the size of the container can be arbitrarily changed in accordance with the number of processed sheets for reforming and the processing efficiency.

  In the method shown in FIG. 1 (b), the processing solution having micro-nano bubbles of ozone generated by the micro-nano bubble generator (not shown) is continuously applied from the injection nozzle 12 to the processing solution 11 having no micro-nano bubbles. Alternatively, metal surface modification is performed by intermittent injection. The surface modification of the metal does not progress so much until the concentration of dissolved ozone contained in the treatment liquid 11 reaches 30 ppm or more, and the concentration of dissolved ozone in the treatment liquid 11 is accompanied by the injection of the treatment liquid having micro and nano bubbles of ozone. From the time when the concentration becomes higher than 30 ppm, substantial surface modification progresses. The temperature of the processing liquid 11 is monitored and controlled by the heater 7, the temperature measuring means 8, the stirrer 9, and a temperature controller (not shown). Further, the dissolved ozone concentration of the treatment liquid 11 is measured by the dissolved ozone concentration sensor 10 before, during or after the treatment. In the method shown in FIG. 1 (b), gas is likely to be generated inside the container 3 by continuous or intermittent injection of the processing solution having micro-nano bubbles of ozone, so It is preferable to provide the degassing pipe 13 having a minute through hole at any place. Although the example which uses the process liquid 11 which does not have a micro nano bubble is shown in (b) of FIG. 1, it may replace with the process liquid 11, and you may use the process liquid which has the micro nano bubble of ozone. In that case, the dissolved ozone concentration is maintained at a high concentration from the beginning of the treatment, and it is possible to maintain the high concentration state during the treatment.

  As shown in (a) and (b) of FIG. 1, in the method of immersing the metal plate 1 in the treatment liquid 2 or 11 having micro / nano bubbles containing ozone, the modification effect of the metal surface is affected by the immersion time. Receive In the present invention, a sufficient surface modification effect can be obtained if the immersion time is within 100 minutes. If the immersion time is longer than that, the surface modification effect tends to be saturated. Although the immersion time can be shortened depending on the ozone concentration of the treatment liquid and the treatment conditions, it is preferable to carry out the immersion for 5 minutes or more in order to perform reliable surface modification.

  (C) of FIG. 1 is a method of performing surface modification of metal while spraying a processing solution 2 having micro / nano bubbles containing ozone to metal 1 for surface modification using a spray nozzle 14 at room temperature. The injection nozzle 14 moves in the horizontal direction along the reforming treatment surface of the metal plate 1. Moreover, the method of fixing the injection | spray nozzle 14 and moving the metal plate 1 according to a modification | reformation process surface may be employ | adopted. The treatment liquid 2 having micro-nano bubbles containing ozone is sprayed to the reformed surface of the metal plate 1 at room temperature, preferably heated or heated to 30 ° C. or higher, more preferably 50 to 90 ° C. The jet speed and jet amount of the treatment liquid 2 jetted from the jet nozzle 14 are designed by a person skilled in the art to carry out usually from the viewpoint of the number of sheets to be treated and the treatment efficiency (treatment time) and the metal surface reforming effect. It can be optimized and selected within the scope of the matter.

  (D) of FIG. 1 is a method of surface modification of metal by spraying a processing solution 2 having micro-nano bubbles containing ozone using a spray nozzle 14 while heating the metal plate 1 for surface modification. It is. With the metal plate 1 for surface modification treatment installed on the heater-containing support plate 15, the treatment liquid 2 having micro / nano bubbles containing ozone is sprayed toward the metal plate 1. At this time, the skirt portion 16 is provided around the heater-containing support plate 15 in order to volatilize the processing solution 2 around the outside of the metal plate 1 and to prevent the heater breakage due to contact with the heater-containing support plate 15 or the like. Here, a separate support plate is separately provided to support the metal plate 1 for surface modification so that the heater-containing support plate 15 does not contact the metal 1 directly, and the metal 1 is heated via the support plate May be adopted.

  In the method shown in (d) of FIG. 1, the metal plate 1 for surface modification is preferably heated to any temperature of 30 to 250 ° C. by the heater-containing support plate 15. More preferably, it is in the range of 30 to 200 ° C. Even if the processing solution 2 having micro / nano bubbles containing ozone is in contact with the surface of the metal plate 1 for a short time by the jet from the jet nozzle 14 and the metal plate 1 is heated to 100 ° C. or higher, It is possible to secure a time for the ozone diffused instantaneously to act directly in the vicinity of the surface of the metal plate 1 to a certain extent. On the other hand, when the heating temperature of the metal plate 1 exceeds 250 ° C., the diffusion speed of ozone becomes very fast, and it becomes difficult to secure a sufficient amount of ozone for oxidizing the surface of the metal plate 1 . Since the surface modification effect of the metal plate 1 does not have a large difference between the heating temperature of the metal plate 1 between 200 ° C. and 250 ° C., adverse effects such as deformation caused by heating the metal plate 1 to 200 ° C. In consideration of this, the heating temperature is more preferably 200 ° C. or less. Thus, by heating the metal plate 1 to a high temperature, surface modification of the metal can be performed efficiently and reliably in a short time. In the method shown in (d) of FIG. 1, not only room temperature but also one heated or heated to 30 ° C. or higher may be used as the treatment liquid 2 having micro-nano bubbles containing ozone.

  As shown in (c) and (d) of FIG. 1, in the method of spraying the treatment liquid 2 having ozone and micro / nano bubbles on the surface of the metal plate 1, the modification effect of the metal surface is affected by the spraying time. . In the present invention, a sufficient surface modification effect can be obtained as long as the spraying time is within 30 minutes. If the spray time is longer than that, not only the surface modification effect tends to be saturated, but also the amount of the treatment liquid is increased, which causes a significant increase in the manufacturing cost and the management cost of the treatment liquid. Further, the lower limit value of the spraying time can be reduced depending on the ozone concentration of the processing solution and the processing conditions, but in order to perform a reliable surface modification, it is preferable to perform the spraying for 5 minutes or more.

  The above is a representative example of the method for modifying a metal surface according to the present invention, but the present invention is not limited to the example shown in FIG.

  Next, a method of generating micro-nano bubbles of ozone used in the method of modifying a metal surface according to the present invention and a device for generating the same will be described with reference to the drawings.

In the preparation of the treatment solution used in the present invention, the average particle diameter is 100 nm or less, preferably 30 nm or less, and the density is controlled to 10 ⁸ or more per 1 ml (liter) of treatment solution. A generation method and its generation device are required. An exemplary configuration of a micro / nano bubble generator capable of realizing the method is shown in FIG. The generator shown in FIG. 2 can be configured as an entire apparatus capable of realizing the method of modifying a metal surface according to the present invention by combining with the parts shown in the schematic view of FIG.

  In FIG. 2, (a) and (b) are respectively a front view and a perspective view of a micro / nano bubble generating device. In FIG. 2, 17 is a bellows cylinder pump, 18 is a pump controller, 19 is a gas-liquid mixing tank, 20 is a pressure sensor, 21 is a micro / nano bubble generating nozzle attachment portion, 22 is a liquid suction pipe, 23 is a gas suction port, 24 is a gas suction adjustment valve.

  These are arranged as shown in the perspective view shown in FIG. The amount of gas is adjusted using the fluid suction pipe 22 and the gas suction adjustment valve 24 by the bellows cylinder pump 17 whose fluid contact part is made of fluorocarbon resin and the liquid and gas are mixed in the pump and sucked in the bellows Internally stir, dissolve, compress and dissolve the gas in the liquid. In the present invention, the bellows cylinder pump 17 may be metal free, and plastics other than fluoroplastics, for example, general purpose plastics such as polyethylene, polypropylene and polyethylene terephthalate, engineering plastics such as polyacetal, polyamide, polycarbonate and modified polyphenylene ether, At least one kind of super engineering such as polyether sulfone, polyphenylene sulfide, polyether ether ketone and liquid crystal polymer may be used. In that case, a highly reliable and clean micro-nano bubble generating device can be obtained by using not only the pump but also the above-described various types of plastics, including fluoroplastics, in the liquid installation part. Further, in the present invention, in the case where cleaning or sterilization by strict metal-free conversion is not required, not only the above-mentioned plastic but also metal or ceramic may be used.

  Next, a gas containing at least ozone and a liquid such as pure water are stirred and sent to the gas-liquid mixing tank 19 by the pump 17. The pump 17 mainly uses a compressed air driven bellows cylinder pump, but may be an electric pump. The gas and liquid in the gas-liquid mixing tank 19 receive the pressure from the pump 17, and the gas is easily dissolved. That is, the pressure for pumping the gas and the liquid from the pump 17 is checked by a pressure sensor 20. By this method, preparation is made to increase the amount of dissolved gas and increase the generation amount of micro / nano bubbles. Although it is practical to use a bellows cylinder pump as the pump 17, it is practical to use the micro / nano valve generation system of the present invention, but depending on the application, the reciprocating motion such as piston pump, plunger pump or diaphragm conventionally known as liquid feed pump A pump, a gear pump, an eccentric pump or a screw pump, a cascade pump, a rotary pump such as a vane pump, or the like can be applied.

  The liquid that is pumped and enters the gas-liquid mixing tank 19 mixes with the gas, and the gas is dissolved in the liquid and then sent to the micro / nano valve generating nozzle attachment 21. The nozzle attachment unit 21 for micro / nano valve generation is a portion for connecting the dissolved gas with a nozzle for producing a large number of micro / nano valves having a diameter of 60 μm or less, preferably 15 μm or less, more preferably less than 10 μm.

  At this time, the dissolved state of the gas / liquid is monitored by observing the fluctuation of the liquid pressure between the nozzle 21 and the gas / liquid mixing tank 19 by the pressure sensor 20. In this way, a stable pressure condition required for a stable micro / nano valve generator nozzle is realized.

  The steps performed using the micro-nano valve generator used in the present invention shown in (a) and (b) of FIG. 2 are as follows. The gas and liquid suction process is performed using the liquid suction pipe 22, the gas suction port 23 and the gas suction adjustment bubble 24. The pressure is adjusted by the pressure sensor 20. Next, the step of pressurizing the liquid containing gas using the bellows cylinder pump 17 is the gas / liquid pressurization step. Subsequently, a process performed using the pump controller 18 and the gas-liquid mixing tank 19 to mix the pressurized liquid containing the gas with a new gas is a dissolved gas enrichment process. Thereafter, the generation nozzle of the present invention to be described later is connected to the micro / nano valve generation nozzle attachment portion 21 and then micro / nano bubbles are generated. This process is called the dissolved gas refining process, but the micro / nano bubbles are injected from the outside of a cylinder having two or more small through holes through the small through holes at a pressure higher than atmospheric pressure and collided at one point inside the above cylinder Can be generated by

  FIG. 3 shows an example of a nozzle shape for generating gas micro-nano bubbles and an example of a nozzle header for ejecting a processing liquid in the micro-nano bubble generator of FIG. In FIG. 3, (a) and (b) are a sectional view and a top view of a nozzle header, respectively. (A) of FIG. 3 has shown the DD cross section of (b).

  As shown in (a) and (b) of FIG. 3, the nozzle header 25 is composed of a jet nozzle 26 for jetting the treatment liquid, a micro / nano bubble discharge nozzle 26 and a table 27, and the liquid collision nozzle One or two or more of the twenty-six (26) are mounted on the twenty-seven platform. Here, the liquid collision nozzle 26 is an example of the nozzle shape that generates gas micro / nano bubbles. The treatment liquid (Q) jetted from the liquid collision nozzle 26 is jetted from the jet port 25 a of the jet nozzle 25 and used as a treatment liquid used in the present invention. In the present invention, the temperature of the treatment liquid is adjusted to 30 ° C. or higher, preferably 50 to 90 ° C. However, the adjustment of the temperature may be performed with the treatment liquid passing through the portion of the nozzle header 25. This is because the correlation between the cleaning ability and the temperature of the processing liquid passing through the portion of the nozzle header 25 is good. In that case, the nozzle header 25 is preferably provided with a temperature sensor for measuring the temperature of the processing liquid.

  FIG. 4 is an enlarged view of a portion where the liquid collision nozzle 26 of the nozzle header 25 shown in FIG. 3A is disposed. As shown in FIG. 4, in one configuration of the 26 liquid impingement nozzles, the small holes of 26a are open towards the center of 26. The liquid entered at high pressure from the arrow Q from this small hole is caused to collide at the center portion of 26 through this small hole to generate micro / nano bubbles. As a result of the experiment, it was found that if the liquid velocity V was controlled, the amount of micro-nano bubbles generated was large and the bubble life was extended. As a measure of the velocity V, when the velocity exceeds 25 m / sec, it becomes a stable micro / nano bubble generation nozzle.

  FIG. 5 is a front view showing an example of a micro / nano bubble generating device used in the method of spraying a treatment liquid shown in (a) or (d) of FIG. 1 in the method of modifying a metal surface of the present invention. The micro / nano bubble generating device shown in FIG. 5 has a heater 28 as a heating means installed at the bottom of the gas-liquid mixing device 19 to heat or heat ozone micro / nano bubbles to a desired temperature of 30 ° C. or higher. , Its temperature can be controlled automatically. The position where the heater 28 is provided is not limited to the bottom of the gas-liquid mixing tank 19, but may be provided on the side of the gas-liquid mixing tank 19, or on both the bottom and the side of the gas-liquid mixing tank 19. . Further, the metal plate 1 is supported on a support rack 29, and by moving either the nozzle header 25 or the support rack 29, a treatment liquid having micro-nano bubbles containing ozone is sprayed on the surface of the metal plate 1. . The support rack 29 may contain a heater for heating.

  FIG. 6 is a front view showing a modified example of the micro / nano bubble generating device used in the method of spraying a treatment liquid in the method of modifying a metal surface according to the present invention. The micro / nano bubble generating device shown in FIG. 6 has a heating device 30 as a heating means, and the heating device 30 heats or heats the micro / nano bubbles of ozone to a desired temperature of 30 ° C. or higher, and the temperature is automatically generated. Can be controlled. The means of spraying the processing solution having micro-nano bubbles containing ozone is basically the same as that shown in FIG.

  In the present invention, in the dissolved gas enrichment step, the solution containing gas micro / nano bubbles is prepared to contain 200 to 15,000 ppm of ozone as a dissolved gas. When the solution is sprayed from outside the cylinder having two or more small through holes 26a in the circumferential direction through the small through holes 26a at a pressure higher than atmospheric pressure, it faces on the same plane parallel to the radial cross section of the cylinder Micro-nano bubbles containing ozone generated by causing the dissolved liquid jetted from the respective openings of the two or more small through holes 26a arranged as described above to collide with the center of the cylinder so that the water hammer is concentrated It is a processing solution which it has.

  The solution in which 200 ppm or more of ozone is dissolved in the dissolved gas enrichment step generates micro / nano bubbles and then the concentration of dissolved ozone decreases to 30 to 40 ppm, and the remaining ozone is contained inside the micro / nano bubbles Exists. The present invention uses the liquid in this state as a processing liquid for the method of reforming the metal surface. Here, in the liquid in which 200 ppm or more of ozone is dissolved, a part of the ozone forms a micro / nano bubble when the micro / nano bubble is generated, and the ozone concentration measured by the dissolved ozone densitometer is actually included in the treatment liquid Less than the concentration of ozone. Thus, the micro-nano bubble generating apparatus shown in FIGS. 2 to 4 coexists in two forms different in the form in which ozone is dissolved and in the form of micro-nano bubbles, and a treatment liquid containing substantially high concentration of ozone. Can be produced. Furthermore, the micro / nano bubbles of ozone contained in the treatment liquid can easily control the average particle size and density within the above range. Therefore, since the processing liquid used in the present invention coexists in the processing liquid with ozone that diffuses in a short period and ozone that can be held for a long time, reforming of the metal surface can be efficiently and effectively performed in a short time. It is believed to have the best form to do.

  The higher the ozone concentration dissolved in the dissolved gas enrichment step, the greater the effect obtained, but the ozone concentration that can be dissolved in the solution is theoretically up to 15000 ppm even in the highest pure water. Therefore, the amount of ozone that can be dissolved in the solution containing gas micro / nano bubbles in the dissolved gas enrichment step is 200 to 15,000 ppm. As the concentration of ozone that can be dissolved in the solution approaches 15000 ppm, the concentration of dissolved ozone in the processing solution obtained after generating micro-nano bubbles of ozone also increases substantially proportionally. For example, when the concentration of dissolved ozone in the solution is about 400 ppm, the dissolved ozone concentration of the treatment solution having micro-nano bubbles of ozone exhibits a value of 60 to 80 ppm, and the remaining ozone is contained in the micro-nano bubbles It can be considered.

  After the metal whose surface has been modified as described above is dried by heating, hot air or cold air in the air or in dry air, it is stored until it is transferred to the step of bonding to the next resin. Or stored.

  The metal whose surface is modified by the modification method of the present invention adheres to the resin by a method generally comprising the following steps. A step of adhering a resin to a metal at room temperature or under heating by any method of potting, injection molding, transfer molding and pressure bonding, and after adhesion to improve adhesion between the metal and the resin. It is a step of heating the metal for a predetermined time or leaving it at room temperature for a predetermined time.

  Further, the metal whose surface is modified by the modification method of the present invention may be adhered to the resin by a resin adhesive. The metal whose surface has been modified by the modification method has improved adhesion to the resin adhesive. On the other hand, since the resin adhesive and the resin have expansion coefficients close to each other, not only the stress generation due to heating at the time of bonding becomes small, but also the adhesion becomes high due to the affinity between both. Therefore, the surface-modified metal / resin adhesive / resin configuration is suitable to improve the adhesion as a whole.

  Furthermore, the metal whose surface has been modified by the modification method of the present invention can be bonded to another metal by means of a resin adhesive. Another metal to be used may be a metal whose surface is modified by the modification method of the present invention or a metal whose surface is not modified. At least, it is possible to improve the adhesion between the surface-modified metal and the resin adhesive.

EXAMPLES Hereinafter, examples based on the present invention will be specifically described, but the present invention is not limited by these examples.

Reference Example 1
With respect to water having gas micro / nano bubbles produced by the nano bubble water generator shown in FIGS. 2 to 6, a confirmation experiment was conducted on the average particle size and density of the micro / nano bubbles actually formed. For confirmation, air nanobubble water containing air as a gas was prepared, and the particle size, number, and size distribution of nanoparticles were measured.

  Air nanobubble water was prepared by a bellows pump type micro / nano bubble generator (装置 PM-5: manufactured by Sigma Technology Co., Ltd.), diluted 100 times with pure water, and used as a measurement sample. Moreover, the pure water before nano bubble preparation was used as a sample for reference. The pure water before nano bubble preparation corresponds to the water which does not contain nano bubbles.

A sample rapid freezing apparatus Vitrobot Mark IV (manufactured by FEI) immediately freezes the air nanobubble water immediately after preparation to prepare a sample in which the nanobubbles are embedded in amorphous ice to prepare a sample for observation. The sample thickness is 200 nm. On the other hand, water (pure water) not containing nanobubbles was also rapidly frozen by the same sample rapid freezing apparatus and used as a reference sample. The sample thickness is 200 nm. Nanobubbles embedded in amorphous ice were directly observed at a sample temperature of about 80 K (Kelvin) using a cryotransmission electron microscope Titan Krios (manufactured by FEI) having an electron energy of 300 keV. The electron beam used for observation was about 20 electrons / Å ² by the low dose technique, and there was almost no rise in the sample temperature during imaging.

  FIG. 7 shows photographs of electron microscopic images of amorphous ice frozen with pure water containing air nanobubbles and amorphous ice frozen with pure water (water not containing nanobubbles). In addition, for air nanobubble water, the particle size distribution of the bubble (a histogram indicating the size dispersion) is shown below the electron micrograph.

The photograph of the electron microscope image shown on the left side of FIG. 7 is an air nanobubble observed immediately after preparation by PMPM-5, and a circular contrast observed in the photograph is a nanobubble. As a result of image processing, the average particle size is 7 nm. The volume of amorphous ice used for the measurement of the histogram is 3.2 × 10 ^-14 cc (400 nm × 400 nm × 200 nm thickness), in which about 260 bubbles are contained. Since the nano bubble water diluted 100 times is observed, the density of the air nano bubble of this nano bubble water is evaluated to be 8.1 × 10 ¹⁷ cells / cc (ml) (81 kyocups / cc (ml)) Ru. On the other hand, in the photograph of the electron microscope image shown on the right side of FIG. 7, it can be confirmed that the ice is amorphous ice, there is no change in contrast, and water is free of bubbles. Thus, not only the presence of nanobubbles contained in water can be directly confirmed as an image by the measurement method and apparatus according to the present invention, but also information on the particle size, number, particle size distribution and morphology of nanobubbles is obtained can do.

Example 1
After preparing ozone nanobubble water with the above-mentioned nanobubble water preparation device PMPM-5 (Bevelose pump type) (manufactured by Sigma Technology Co., Ltd.), measure the sample which is about 100 times diluted with pure water. Used as The sample thickness is 200 nm. After rapidly freezing this sample in the same sample quick freezing apparatus as in Example 1, nanobubbles embedded in amorphous ice were observed directly at a sample temperature of about 80 K by the same cryotransmission electron microscopy as in Example 1. The electron beam used for observation was about 20 electrons / Å ² by the low dose technique, and there was almost no rise in the sample temperature during imaging.

The photograph of the electron microscope image observed using this sample and the particle size distribution of the bubble (a histogram showing the size dispersion) are shown in FIG. 8 below the photograph. The image shown in FIG. 8 is an observation of an ozone nanobubble about half a month after preparation by PMPM-5. The average particle size is 18 nm, which is slightly larger than the air nanobubbles shown in FIG. 8, and it is considered that the coarsening of the size is also caused by the coalescence. The volume of amorphous ice used for the measurement of the histogram is 3.2 × 10 ^-14 cc (400 nm × 400 nm × 200 nm thickness), in which about 21 bubbles are contained. Since the nanobubble water diluted 100 times is observed, the density of ozone nanobubbles of this nanobubble water is estimated to be 8.6 × 10 ¹⁶ cells / cc (ml) (about 9 K pcs / cc (ml)) Be done.

Example 2
Using pure water containing ozone nanobubbles shown in FIG. 8 as a treatment liquid for reforming the metal surface, using a copper plate (Cu plate: length × width × thickness = 71 mm × 25 mm × 1.5 mm) as a metal plate According to the method shown in (a) of FIG. 1, the surface modification treatment of the Cu plate was performed by the immersion method. The pure water containing ozone nanobubbles used in the present embodiment is prepared as the solution containing ozone generated by the ozone generator in the dissolved gas enrichment step using the solution prepared to have a dissolved ozone concentration of 200 ppm or more. It was produced by an apparatus PMPM-5. The solution thus prepared was used immediately as a processing solution for modification after confirming that the visible micro level bubbles had disappeared. Therefore, it is considered that the ozone nanobubbles contained in this treatment liquid have a smaller average particle size and a higher density than those shown in FIG. The dissolved ozone concentration in the treatment liquid was measured using a dissolved ozone densitometer EL-600 (manufactured by Ebara Corporation).

After the surface modification is carried out in this way, a polyphenylene sulfide resin (PPS) is injection molded in a predetermined shape (length × width × plate thickness = 25 mm × 25 mm × 3 mm) at one end of the dried Cu plate To produce a sample for adhesion test as shown in FIG. Thereafter, the adhesion between the Cu plate and the PPS resin was evaluated by a tensile shear test. The area of the bonding portion was 150 mm ² (length × width = 6 mm × 25 mm). Injection molding of the PPS resin was performed under the conditions generally employed when producing a metal insert resin molded article, and the cylinder temperature was set to 330 ° C. The tensile shear test was performed by Shimadzu autograph at a tensile speed set to 5 mm / min. The adhesive strength was measured by selecting 2 to 5 of the Cu plates immersed in the treatment liquid, with the conditions of the treatment liquid temperature and the immersion time being changed.

Comparative Example 1
The surface modification treatment of the Cu plate was performed in the same manner as in Example 2 using saturated ozone pure water having no micro / nano bubbles as the treatment solution. This treatment liquid had a dissolved ozone concentration of 16.8 ppm measured at 15 ° C. The adhesion between the Cu plate after treatment and PPS was measured by a tensile shear test under the same measurement conditions after injection molding of a PPS resin in the same manner as in Example 2.

Comparative Example 2
The treatment was carried out using a chemical solution containing triazine thiol known as surface modification treatment of Cu, instead of the treatment liquid having micro-nano bubbles containing ozone. The adhesion between the Cu plate after treatment and PPS was measured by a tensile shear test under the same measurement conditions after injection molding of a PPS resin in the same manner as in Example 2. As a result, the tensile shear adhesive strength was 19.0 MPa at the maximum value.

  The measurement results of the adhesion between the Cu plate and the PPS resin according to this example are shown in Table 1 below together with Comparative Examples 1 and 2. In Table 1, the number of processed Cu plates is the number of Cu plates contained in a predetermined amount (ml) of treatment solution, and the dissolved ozone concentration in the treatment system is the concentration measured at room temperature (15 ° C.) before treatment. Shows the concentration measured at the treatment solution temperature during the immersion treatment (measured at 50 ° C in the case of treatment at 50 ° C), and the temperature (° C) of the treatment solution is the surface modification treatment of the Cu plate Means the temperature of the processing solution when The adhesion shown in Table 1 indicates the measured values of each sample and their average value.

  As shown in Table 1, Example 2 using a Cu plate surface-modified with a processing solution having micro-nano bubbles containing ozone, as compared with Comparative Example 1 in which it is treated with saturated ozone water, is different from PPS resin It can be seen that it shows high adhesion between them. Comparative Example 1 is saturated ozone water, but it is considered that ozone can not be held in water because micro / nano bubbles are not formed, and the dissolved ozone concentration tends to be low. In addition, it can be seen that significant improvement in adhesion is seen in Example 2 when Example 2 is compared with Comparative Example 1 for the Cu plate subjected to the immersion treatment for 10 minutes and 40 minutes at an immersion temperature of 15 ° C. . Thus, the difference in adhesion between the two is largely affected not only by the difference in the dissolved ozone concentration, but also by the presence of micro / nano bubbles of ozone contained in the treatment liquid. It is apparent that the reason why the surface modification effect of the Cu plate is greatly improved in Example 2 is because the processing solution contains micro-nano bubbles of ozone.

  As can be seen from Table 1, the adhesion to the PPS resin in Example 2 not only increases as the time for immersing the Cu plate in the treatment liquid having micro / nano bubbles increases, but also the variation in adhesion decreases. There is a tendency. For example, a Cu plate which has been subjected to an immersion treatment at an immersion temperature of 15 ° C. for 10 minutes has a sample with an adhesion of less than 10 MPa, but any sample has an adhesion of more than 10 MPa when the immersion time is 20 minutes or more It was obtained. Furthermore, regarding the difference due to the temperature of the treatment liquid, the Cu plate treated at 50 ° C. has higher adhesion to the PPS resin than the one treated at 15 ° C. In particular, the Cu plate subjected to the immersion treatment at an immersion temperature of 50 ° C. for 60 minutes has the highest adhesion, and the average value of the adhesion is equal to the maximum value of Comparative Example 2 treated with the triazine thiol chemical solution. Show.

  As shown in Comparative Example 2, it is known that the adhesion of a Cu plate to a PPC resin can be extremely increased by treating it with a triazine thiol-based chemical solution. In the case of chemical treatment, if an ideal treatment can be performed, it is possible to obtain a Cu plate having high adhesion and little variation in adhesion. However, on a mass production basis, the variation is very large, and the reality is that it has not reached the practical application on a mass production basis. Furthermore, in the case of chemical treatment, it is generally difficult to manage, store and dispose of the treatment solution. On the other hand, the Cu plate whose surface is modified in Example 2 can not only achieve a significant improvement in the adhesion to the PPS resin but also reduce the variation in adhesion. Furthermore, since the treatment liquid used in Example 2 only contains water and gas such as ozone, if care is taken to exhaust gas such as ozone, management, storage and disposal of the treatment liquid are in the case of chemical solution It is easier than. Therefore, the reforming method of the present invention can be expected to be applied to mass production.

  Next, in order to grasp the surface state of the surface-modified Cu plate in Example 2, the surface of the Cu plate was observed with a scanning electron microscope (SEM). At the same time, elemental analysis observed on the surface of the Cu plate was performed by energy dispersive X-ray spectroscopy (SEM-EDX). As a measurement sample, one (Cu plate subjected to immersion treatment at 50 ° C. for 60 minutes) showing the highest adhesive strength (20.1 MPa) in Table 1 as a representative sample of Example 2 was used. The SEM photograph (1000 magnifications) of Cu plate surface before resin adhesion | attachment and the abundance of each element are respectively shown to (a) and (b) of FIG.

  As shown in (a) of FIG. 10, the surface-modified Cu plate has no holes or holes on the surface, and has a smooth surface. Further, as understood from the elemental analysis shown in (b) of FIG. 10, in addition to Cu, elements of oxygen (O) and carbon (C) were observed on the surface of the Cu plate. Among them, carbon (C) is considered to be due to adsorption of carbon in air. On the other hand, oxygen (O) is an element that exists before surface modification because copper is easily oxidized, but the surface-modified Cu plate exhibits a surface that is significantly discolored compared to that before treatment. Was visually confirmed. Accordingly, the surface-modified Cu plate in Example 2 is considered to be that the surface oxidation is progressed by the treatment solution having micro-nano bubbles of ozone, whereby the adhesion to the PPS resin is improved. However, with respect to the improvement of adhesive strength, it is unclear at present whether or not the effect of the surface roughening due to the surface modification of the Cu plate is detailed, and it is necessary to analyze the surface shape of the Cu plate in detail.

Example 3
Using pure water containing ozone nanobubbles shown in FIG. 8 as the treatment liquid for modifying the metal surface, using a copper plate of the same size as that of Example 2 as the metal plate, the immersion method according to the method shown in FIG. Surface modification treatment of the Cu plate was performed. First, 3000 ml of ion-exchanged water is placed in a container 3 and then the ion-exchanged water is circulated in a state where nine Cu plates 1 before reforming are immersed. The ion-exchanged water transferred from the container 3 is introduced into the nanobubble water preparation device PMPM-5, and the ozone generated by the ozone generator is mixed in the gas-liquid mixing tank provided in ΣPM-5, and the dissolved ozone concentration is 200 ppm or more Prepare to. The ion-exchanged water thus prepared is used as a treatment liquid having micro-nano bubbles of ozone after the micro-nano bubbles of ozone are produced by the above-mentioned nano-bubble water producing device PMPM-5 into the container 3 from the injection nozzle 12 Be injected. With the passage of time of circulation and immersion, the ion-exchanged water stored in the container 3 not only gradually increases in the concentration of dissolved ions, but also the density of micro-nano bubbles of ozone.

  After the surface modification is performed in this manner, polyphenylene sulfide resin (PPS) is injection molded on one end of the dried Cu plate, and the adhesion between the Cu plate and the PPS resin in the same manner as in Example 2. Was evaluated. The adhesive strength was measured by selecting three of the Cu plates immersed in the treatment liquid for different immersion time conditions. The measurement results of adhesion are shown in Table 2 below.

  As can be seen from Table 2, the amount of the processing solution having micro-nano bubbles of ozone increases with the passage of immersion time, so the concentration of dissolved ozone in the processing solution (ion-exchanged water) measured during the processing becomes high. Along with this, the adhesion between the surface-modified Cu plate and the PPS resin is high. Although Table 2 only shows the results up to 20 minutes as the treatment time, when the immersion time is further extended, the adhesion strength is further improved, and it can be expected that the dispersion of the adhesion strength is reduced. Thus, it has been confirmed that surface modification of the Cu plate proceeds by introducing a processing solution having micro-nano bubbles containing ozone and increasing the ratio in the processing solution.

Example 4
In addition to the nanobubbles containing ozone shown in FIG. 8, pure water further containing a gas of carbon dioxide (carbon dioxide gas) is used as a treatment liquid for reforming the metal surface, and a copper plate of the same size as that of Example 2 as a metal plate. The surface modification treatment of the Cu plate was performed by a spraying method according to the method shown in FIG. The pure water having nano bubbles used in the present embodiment introduces ozone and carbon dioxide gas (amount of about 1/5 of the amount of ozone) generated by the ozone generator in the dissolved gas enrichment step, and the dissolved ozone concentration is 200 ppm Using the above prepared, it was manufactured by the nano bubble water manufacturing apparatus ΣPM-5. The liquid thus produced was heated to about 60 ° C. by the heater 27 as in the apparatus shown in FIG. 5, for example, and was immediately used as a treatment liquid for reforming. The nanobubbles contained in this treatment liquid and containing ozone and carbon dioxide gas have an average particle diameter of less than 30 nm as a result of measurement according to the same method as in Example 1, and the density per 1 ml of treatment liquid is 10 ¹⁶ particles / cc (ml ) Was confirmed. In addition, when a processing solution having nanobubbles containing ozone and carbon dioxide gas is applied to a Cu plate and heated to about 60 ° C., the nozzle 14 is arranged so that the processing solution is concentrated on the bonding portion with the PPS resin. Made a move. The spraying time was 20 minutes.

  The polyphenylene sulfide resin (PPS) was injection molded on one side of the Cu plate whose surface was modified as described above in the same manner as in Example 2 to prepare a sample for adhesion test as shown in FIG. After that, the adhesion between the Cu plate and the PPS resin was evaluated by a tensile shear test. As a result, the adhesive force was 12 MPa or more in all samples, and the adhesive force variation was also small.

  As described above, according to the present invention, not only the method of immersing the Cu plate in the treatment solution having the micro / nano bubbles containing ozone at least as gas, but also performing the surface modification treatment of the Cu plate It has been confirmed that a sufficient surface modification effect can be obtained also by the method of spraying on the surface of. In addition, although the results in the case of using Cu as the metal are shown in the above examples, the present invention is not limited to Cu, and can be applied to, for example, aluminum, iron, nickel, phosphor bronze and the like. In addition, application to alloys other than copper, aluminum, iron and the like, and Pt, Au and the like in which surface modification is difficult is also possible.

  As described above, since the method for modifying a metal surface according to the present invention contains a high concentration of ozone and simultaneously uses a treatment liquid containing micro-nano bubbles of ozone, it is possible to spray the treatment liquid or use the treatment liquid. Surface modification can be performed efficiently and effectively by a simple method such as immersion. Furthermore, the oxidation reaction can be promoted and the modification effect can be improved by increasing the density of the micro / nano bubbles of ozone contained in the treatment liquid. In addition, micro-nano bubbles of ozone used in the present invention are highly effective in suppressing the diffusion of ozone in the atmosphere while containing ozone with high concentration, as compared with conventional ozone gas and ozone water. Therefore, metal surface treatment can be performed more efficiently and reliably than the conventional method while reducing the load on the environment.

  The surface-modified metal according to the present invention has high adhesion to the resin, and the variation in adhesion between lots can be extremely reduced. Furthermore, the adhesion between metal and resin can be made simply by utilizing a conventionally established adhesion method without employing a particularly difficult method or process. Therefore, not only the adhesion between the metal and the resin can be increased but also the manufacturing cost can be simultaneously reduced. Since the modification method and the bonding method of the present invention can be expected to be applied to parts and devices composed of metal and resin used in various fields such as household appliances, industrial instruments, and public appliances, the utility thereof Is very expensive.

DESCRIPTION OF SYMBOLS 1 ... Metal plate, 2 ... Treatment liquid, 3 ... Container 4 ... Support stand, 5 ... Fine wire, 6 ... Lid of a container, 7 ... Heater, 8 ... Temperature measurement means, 9: stirrer, 10: dissolved ozone concentration sensor, 11: treatment solution without micro and nano bubbles, 12: micro and nano bubble generation nozzle, 13: gas vent pipe, 14 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · bellows cylinder pump · · Pressure sensor, 21 · · · micro · nano bubble generating nozzle mounting portion, 22 · · · liquid suction pipe, 23 · · · gas suction port, 24 · · · gas suction adjustment valve, 25 · · · · · · · · 26 ・ ・ ・ Micro and nano bubble discharge nozzle , 27 ... base, 28 ... heater, 29 ... support cradle, 30 ... heater.

Claims (14)

A method of reforming a metal surface by a treatment liquid having gas micro / nano bubbles, wherein the gas contains ozone, and the dissolved ozone concentration in the treatment liquid is measured at room temperature (10 to 25 ° C.). and at 30ppm or more and an average particle size and density of the micro-nano bubbles of gas contained in the treatment liquid is, when measured by cryo transmission electron microscopy by Koritsutsumiuma method, 30 nm respectively per below and 1 ml 10 ^A method of modifying a metal surface using micro / nano bubbles characterized by having ^eight or more . The treatment liquid containing the micro / nano bubbles of the gas injects a solution containing 200 to 15,000 ppm of ozone as a dissolved gas from the outside of a cylinder having two or more small through holes in the circumferential direction through the small through holes at a pressure above atmospheric pressure. When making it run, the water hammer concentrates the dissolved liquid sprayed from the respective openings of the two or more small through holes arranged opposite to each other on the same plane parallel to the radial cross section of the cylinder at the center of the cylinder 2. A method of modifying a metal surface using micro / nano bubbles according to claim 1 , wherein the processing liquid has micro micro / nano bubbles of gas generated by collision. The gas, in addition to ozone, carbon dioxide, a gas containing at least one of hydrogen peroxide and oxygen, according to claim 1, wherein said treatment solution is pure water containing the micro-nano bubble Or 2. The method for modifying a metal surface using the micro / nano bubbles according to the above 2 . The temperature of the process liquid which has the micro nano bubble of the said gas is 30 degreeC or more, The modification | reformation method of the metal surface using the micro nano bubble in any one of the Claims 1-3 characterized by the above-mentioned. 5. The method for modifying a metal surface using micro / nano bubbles according to claim 4 , wherein the temperature of the treatment liquid having the gas micro / nano bubbles is 50 to 90 ° C. A method for modifying a metal surface using micro / nano bubbles, comprising immersing the metal in the treatment liquid according to any one of claims 1 to 5 . The method for modifying a metal surface using micro / nano bubbles according to claim 6 , wherein the time for which the metal is immersed in the treatment liquid is within 100 minutes. A method of modifying a metal surface using micro / nano bubbles, comprising spraying the treatment liquid according to any one of claims 1 to 5 to the metal. A method of modifying a metal surface using micro / nano bubbles, comprising spraying the treatment liquid according to any one of claims 1 to 3 to a metal heated to 30 to 250 ° C. The method for modifying a metal surface using micro / nano bubbles according to claim 8 or 9 , characterized in that the spraying time is within 30 minutes in the step of spraying the treatment liquid onto the metal. A method of modifying a metal surface using micro / nano bubbles, comprising the step of drying the metal whose surface has been modified by the modifying method according to any one of claims 1 to 10 . Bonding a resin by potting, injection molding, transfer molding and pressure bonding at room temperature or under heating, with a metal whose surface is modified by the modification method according to claim 11 ; A method for bonding metal and resin, comprising the steps of heating the metal after bonding for a predetermined time or leaving it at room temperature for a predetermined time in order to improve the adhesion to the resin. A method of bonding metal and resin, comprising the step of bonding the metal whose surface is modified by the method of modification according to claim 11 to the resin with a resin adhesive. Bonding the metal whose surface has been modified by the modification method according to claim 11 with a metal whose surface has been modified with a resin adhesive or a metal different from the metal whose surface has been modified; How to bond metal and resin.

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