JP2006057061A - Adhesive sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive sheet that enables control of a mixing ratio of a surfactant and water in a water-wetting sticking work, makes a positioning work easy and does not generate bubbles in a sheet-sticking work. <P>SOLUTION: The adhesive sheet comprises an adhesive layer 2 containing microcapsules 3 in the adhesive layer, wherein at least one part of the microcapsules 3 is placed on the surface of the adhesive layer 2, and is so constructed that the microcapsules 3 are ruptured by pressurization and release the surfactant and water. Alternatively, the adhesive sheet has an adhesive layer and is so constructed that the microcapsules are stuck on the surface of the adhesive layer and the microcapsules are ruptured by pressurization and release the surfactant and water. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to an adhesive sheet, and relates to an adhesive sheet that has good workability and can be easily attached without requiring skill, especially when water is attached.

  When constructing an adhesive sheet, air bubbles may enter between the construction surface of the adherend and the adhesive sheet, or the bonding position may not match. When air bubbles enter, the adhesive sheet becomes uneven or easily peels off, so in order to remove the air bubbles, a work such as expelling the air bubbles with a spatula or piercing a needle or the like to remove air from the hole is performed. Yes. Furthermore, when bubbles cannot be removed even in these operations, or when the bonding position does not match, the operation of removing the adhesive sheet and re-adhering is performed.

  However, removing the adhesive sheet that has been bonded once and reapplying it causes the surface of the adhesive sheet to be wrinkled or scratched, or causes the adhesive sheet to easily peel off from the adherend.

  In order to solve this problem, a method of wetting an adherend or an adhesive sheet with water before bonding the adhesive sheet is generally performed (see Patent Document 1).

  In this method, by interposing water between the adherend and the adhesive sheet, the adhesion can be made low and slippery at the beginning of bonding, and then the water is completely evaporated by evaporation. It comes to adhere. Therefore, bubbles can be pushed out in a slippery state at the beginning of bonding, and the position can be finely adjusted.

  However, in such an operation called water sticking, water is generally applied by spraying, but it is difficult to adjust the amount of water, and slipping is manifested if there is not enough water between the adherend and the adhesive sheet. Without being able to push out bubbles or shift their position. If this water pasting operation is to be performed purely with water, the adherend must be thoroughly washed to completely remove dirt, dust, foreign matter, etc., and the gap between the adherend and the adhesive layer must be removed. In addition, it is difficult to provide a uniform layer of water. Therefore, a surfactant is mixed with water. However, if the ratio of the surfactant to water is too small, repelling occurs and a uniform layer of water cannot be obtained. On the other hand, if the ratio of the surfactant is too high, there will be more bubbles due to the influence of the surfactant during spray coating, and there will be more bubbles when bonded, uneven bonding will occur, and it will be easy to peel off It becomes.

JP 2000-96009 A (prior art)

  As a result of diligent research to solve the above-mentioned problems, the present inventor easily arranges the interface on the surface of the adhesive layer of the adhesive sheet by disposing the microcapsules that release the surfactant and / or water by breaking due to pressurization. The ratio between the activator and water can be adjusted, and it has been found that water can be applied under appropriate conditions, and this has been solved.

  That is, the adhesive sheet of the present invention is an adhesive sheet having an adhesive layer containing a microcapsule in the adhesive layer, and the surfactant is applied to the surface of the adhesive layer by breaking the microcapsule by pressurization. And water is discharged.

  The adhesive sheet of the present invention is an adhesive sheet having an adhesive layer containing microcapsules and an adhesive resin, wherein the specific gravity of the microcapsules is smaller than the specific gravity of the adhesive resin. It is characterized by releasing the surfactant and water to the surface of the adhesive layer by breaking the layer with pressure.

  Further, the adhesive sheet of the present invention is an adhesive sheet having an adhesive layer, wherein the microcapsule is attached on the adhesive layer, and the microcapsule is destroyed by pressurization, whereby the surface of the adhesive layer is obtained. It is characterized by releasing surfactant and water.

  Since the adhesive sheet of the present invention has microcapsules that release surfactant and / or water from individual microcapsules due to breakage due to pressurization, the ratio of surfactant to water can be easily determined. Provided is an adhesive sheet that can be adjusted and can be easily water-adhered without requiring a technique skilled in water adhering.

  First, an embodiment of the adhesive sheet of the present invention will be described. The adhesive sheet of the present invention is an adhesive sheet having an adhesive layer containing a microcapsule in the adhesive layer, and the surface of the adhesive layer is removed from the surface of the adhesive layer by breaking the microcapsule by pressure. Is released.

  A second embodiment of the adhesive sheet of the present invention is an adhesive sheet having an adhesive layer, in which a microcapsule is attached on the adhesive layer, and the microcapsule is broken by pressurization. Further, it is characterized by releasing a surfactant and water.

  The adhesive sheet of the present invention contains microcapsules in the adhesive layer or on the adhesive layer. For example, the adhesive sheet can have a configuration having the adhesive layer on the substrate. Specifically, as shown in FIGS. 1 and 2, when the microcapsule 3 is present in the form included in the adhesive layer 2, and when the microcapsule 3 is placed on the adhesive layer 2 as shown in FIG. May adhere. With this configuration, the ratio of the surfactant and water can be adjusted.

  In order to release the surfactant and water from the microcapsules in the adhesive layer to the surface of the adhesive layer, at least a part of the microcapsules may be present on the surface of the adhesive layer. The capsule does not have to be placed on the surface of the adhesive layer. When the microcapsules are arranged on the surface of the adhesive layer, it is particularly preferable that the microcapsules protrude from the adhesive layer as shown in FIG. As a method for causing the microcapsules to be present on the surface, for example, a method in which at least a part of the microcapsules is arranged on the surface of the adhesive layer by making the specific gravity of the microcapsules smaller than an adhesive resin constituting the adhesive layer described later. and so on. Further, as a method for causing the microcapsules to protrude from the adhesive layer, there is a method of making the particle size of the microcapsules larger than the thickness of the adhesive layer. Even when the microcapsules are not arranged on the surface, by using a method such as making the adhesive layer porous, the microcapsules are destroyed in the adhesive layer, and the surfactant and water ooze out to the surface of the adhesive layer. There is no problem because the adhesive layer can be configured as described above.

  Further, as shown in FIG. 2, as a method of attaching the microcapsules on the adhesive layer, a method of transferring the microcapsules arranged at a desired interval to the surface provided with the adhesive layer, or spraying the microcapsules on the adhesive layer. Methods. In this method, the compatibility between the solvent for dissolving the adhesive resin and the wall material of the microcapsule is not so much, so that a general adhesive layer can be used and the microcapsule is placed on the outermost surface of the adhesive layer. Therefore, the surfactant and / or water can be easily released on the surface of the adhesive layer, which is preferable.

  The substrate used in the adhesive sheet of the present invention is not particularly limited, and any material can be used as long as it can provide an adhesive layer, such as a polymer film or synthetic paper. Moreover, what gave printability and mold release property to a base material may be used, and a printed matter, a window film, etc. may be used as a base material.

  The adhesive layer is mainly composed of an adhesive or an adhesive. Such an adhesive or adhesive is an adhesive resin, such as vinyl acetate resin, modified vinyl acetate resin, modified vinyl acetate-acrylic copolymer resin, ethylene-vinyl acetate copolymer resin, polyester resin, Examples thereof include acrylic copolymer resins, cellulose resins, vinyl chloride-vinyl acetate copolymer resins, urethane resins, epoxy resins, modified polyvinyl alcohol resins, and acrylonitrile rubbers.

  The thickness of the adhesive layer is not particularly limited, but the lower limit is preferably 2 μm or more. By setting the thickness of the adhesive layer to 2 μm or more, flexibility can be improved. In particular, when the adhesive layer is made of a pressure-sensitive adhesive, the flexibility can be further improved. The upper limit of the thickness of the adhesive layer is preferably 100 μm or less. Moreover, you may add additives, such as a ultraviolet absorber, an infrared absorber, a moistureproof agent, a coloring agent, and a electrically conductive agent, to an contact bonding layer.

  The microcapsules used in the present invention can release surfactants and / or water from individual microcapsules by breakage due to pressurization. The wall material used for the wall film of the microcapsule is not particularly limited as long as it can contain a surfactant and / or water and is not affected by the above-mentioned adhesive. For example, urea resin , Synthetic resin such as melamine resin, polyurethane, polyvinyl chloride, polycarbonate, polystyrene, polyacryl, polyamide, vinyl chloride-vinyl acetate copolymer, polyester, ketone resin, or gelatin, gum arabic, ethyl cellulose, casein, polyvinyl alcohol Etc. In particular, when the microcapsules are arranged on the surface of the adhesive layer due to the difference in specific gravity between the microcapsules and the adhesive resin, ethyl cellulose (specific gravity 1.09 to 1.17), adhesive resin as the wall material of the microcapsules A combination of acrylic copolymer resin (specific gravity 1.17 to 1.20) is preferable.

  Such microcapsules use the above wall material, interfacial polymerization method, in situ polymerization method, submerged curing coating method, coacervation (phase separation) method, interfacial precipitation method, spray-dry method, suspension in air It can be produced by encapsulating a surfactant and / or water in a microcapsule according to a known microencapsulation technique by a coating method, a high-speed air impact method, or the like.

  The particle size of the microcapsule is about 0.1 to 500 μm, preferably about 1 to 100 μm. By setting the thickness to 0.1 μm or more, it is difficult to apply a compression pressure that breaks the microcapsules, and it is possible to prevent the microcapsules from being broken when necessary. In addition, in the case of large microcapsules, the number of microcapsules per unit area can be reduced when the size is 500 μm or less, but the corresponding area is widened by one microcapsule, and the water level is reduced after the microcapsules are destroyed. It is difficult to get more. And even if the number of microcapsules per unit area is increased in order to obtain a uniform layer of water, the workability of water pasting is not affected and only the microcapsules are consumed. In addition, when the microcapsules of the adhesive layer are included, it is preferable to use microcapsules having a particle size equal to or smaller than the thickness of the adhesive layer in order to prevent the microcapsules from excessively protruding from the adhesive layer.

  And if the microcapsule is too hard, it will not break, so the purpose of releasing surfactant and water cannot be achieved, and if it is too soft, the microcapsule will be broken by the time it sticks to the adherend. Will cause inconvenience. For this reason, what a microcapsule is destroyed by the pressurization of about 200-2000 kPa is preferable.

  Each microcapsule contains a surfactant and water, or a surfactant or water. As the surfactant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant can be used, and an anionic surfactant and a nonionic surfactant are particularly preferable. . The ratio of the surfactant is 0.01% by weight or more, preferably 0.02% by weight or more of the total weight of the surfactant and water, and the upper limit is not particularly limited unlike spray coating. Preferably, it is about 2 wt% or less, more preferably about 1 wt% or less. By setting it as such a range, the uniform layer of water can be obtained, without generating repellency etc. Moreover, since spray coating is not performed, even if the ratio of the surfactant to water increases, bubbles are not generated, and a uniform layer of water can be obtained satisfactorily.

  Such surfactant and water-containing microcapsules, or when surfactant and water are included in separate microcapsules, both microcapsules are added to the surface of the adhesive layer to add When the microcapsules are broken by the pressure, the surfactant and / or water contained in each microcapsule becomes a water film on the surface of the adhesive layer to form a uniform layer of water. In this way, by appropriately distributing the microcapsules on the surface of the adhesive layer, the ratio of the surfactant and water can be adjusted, so that water can be easily applied even without skilled techniques. become.

  Hereinafter, the present invention will be further described by way of examples. “Parts” and “%” are based on weight unless otherwise specified.

[Preparation of microcapsules]
A microcapsule having a particle size of 50 μm to 100 μm was prepared by an interfacial precipitation method using a linear alkylbenzene sulfonate (surfactant) 1% solution in water as a solvent and ethyl cellulose as a wall material.

[Example 1]
An adhesive layer coating solution having the following formulation was applied and dried to a thickness of 50 μm on a biaxially stretched polyethylene terephthalate film (Lumirror T60: Toray Industries, Inc.) having a thickness of 100 μm to form an adhesive layer. 1 adhesive sheet was produced. The specific gravity of the microcapsule was smaller than the specific gravity of the adhesive resin.

<Adhesive layer coating solution>
・ Acrylic copolymer resin (solid content 60.5%) 100 parts
(E-1000: Soken Chemical)
・ 30 microcapsules

[Example 2]
On the biaxially stretched polyethylene terephthalate film (Lumirror T60: Toray Industries, Inc.) having a thickness of 50 μm, an adhesive layer coating solution having the following formulation was applied and dried so that the thickness after drying was 50 μm, thereby forming an adhesive layer. The microcapsules were adhered to the adhesive layer so as to form a uniform layer, and an adhesive sheet of Example 2 was produced.

<Adhesive layer coating solution>
・ Acrylic copolymer resin (solid content 60.5%) 100 parts
(E-1000: Soken Chemical)

[Comparative Example 1]
On the biaxially stretched polyethylene terephthalate film (Lumirror T60: Toray Industries, Inc.) having a thickness of 100 μm, the adhesive layer coating solution having the following formulation is applied and dried so that the thickness after drying is 50 μm, and an adhesive layer is formed. 1 adhesive sheet was produced.

<Adhesive layer coating solution>
・ Acrylic copolymer resin (solid content 60.5%) 100 parts
(E-1000: Soken Chemical)

  The adhesive sheets obtained in Examples 1 and 2 and Comparative Example 1 were bonded to a window glass, and the ease of alignment and the condition of bubbles were visually confirmed. Moreover, about the adhesive sheet of the comparative example 1, water pasting was further performed on three conditions, and the ease of position alignment and the condition of bubbles were visually confirmed. The results are shown in Table 1. In addition, the ease of alignment was evaluated in four steps from A to X in order from the best.

  As a result, both Examples 1 and 2 are easy to align at the time of bonding, and after bonding, bubbles can be moved to the outside of the sheet using a squeegee, and bubbles are also observed after finishing. There wasn't. On the other hand, the thing of the comparative example 1 did not perform water sticking, but when it stuck on the window glass as it was, position alignment was difficult and the bubble could not be moved to the outer side of a sheet | seat, and the bubble was observed after finishing . In addition, when it was pasted to the window glass under different water pasting conditions, in the case of water alone, the surfactant was not included, so the slipperiness was poor, and alignment was not possible unless a large amount of water was used. It was. In addition, water was repelled and bubbles were observed. On the other hand, in the case where a large amount of the surfactant was contained by water sticking, the alignment was good due to the influence of the surfactant, but bubbles generated during spray coating became bubbles.

Sectional drawing which shows one Example of the adhesive sheet of this invention Sectional drawing which shows the other Example of the adhesive sheet of this invention Sectional drawing which shows the other Example of the adhesive sheet of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Adhesion layer 3 ... Microcapsule 4 ... Adhesive sheet

Claims (3)

  An adhesive sheet having an adhesive layer containing a microcapsule in the adhesive layer, wherein the microcapsule is broken by pressurization to release a surfactant and water on the surface of the adhesive layer. Adhesive sheet.   An adhesive sheet having an adhesive layer containing a microcapsule and an adhesive resin, wherein the specific gravity of the microcapsule is smaller than the specific gravity of the adhesive resin, and the microcapsule is broken by pressurization, An adhesive sheet that releases a surfactant and water to the surface of the adhesive layer.   An adhesive sheet having an adhesive layer, wherein a microcapsule is adhered on the adhesive layer, and the surfactant and water are released to the surface of the adhesive layer by breaking the microcapsule under pressure. An adhesive sheet characterized by that.

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