KR100777527B1 - Solid-phase adhesives and liquid-phase raw composition thererof - Google Patents

Abstract

The present invention relates to a solid adhesive having improved initial adhesion while maintaining good applicability to an adherend, and a raw material liquid composition for preparing such a solid adhesive, comprising a component derived from a water-soluble adhesive polymer and an aqueous polymer emulsion. In the solid adhesive included as a component, solid content of the component derived from the said aqueous polymer emulsion is 0.01-30 mass% with respect to the total amount of solid content of the said water-soluble adhesive polymer and the component derived from the said aqueous polymer emulsion. It is a shape adhesive.

Solid adhesives, water soluble adhesive polymers, aqueous polymer emulsions

Description

Solid-phase adhesives and liquid-phase raw composition thererof}

The present invention relates to a solid adhesive having excellent adhesion and coating property to an adherend, and a raw material liquid composition for preparing such a solid adhesive.

A so-called stick paste is known in which a long-chain fatty acid salt or the like is a gelling agent for maintaining a shape, and a lipstick-type container filled with a solid adhesive mainly composed of a water-soluble adhesive polymer such as polyvinylpyrrolidone (PVP).

In such a solid adhesive, it is required to have excellent initial adhesiveness with a short time to apply the required adhesion force when applied to one of a set of adherends and then bonded with the other adherend, and various improvements are required. It is done.

For example, Japanese Patent Application Laid-Open No. 54-34342 proposes a technique for improving the initial adhesiveness of a solid adhesive by using an emulsion material (aqueous polymer emulsion) together with a water-soluble polymer such as PVP. The technique of this publication uses a large amount of aqueous polymer emulsion to improve its initial adhesiveness.

However, according to the researches of the present inventors, when the solid content of the water-based polymer emulsion increases with respect to the total amount of the solid content (polymer particles) in the water-soluble polymer and the water-based polymer emulsion, the hardness of the solid adhesive is lowered, thereby impairing the shape retention. It turned out that applicability | paintability to a to-be-adhered body deteriorates. In addition, although the technique of Unexamined-Japanese-Patent No. 54-34342 uses a gelatinizer (long-chain fatty acid salt) in large quantities, it is thought that the shape retention property is improved and the applicability | paintability to a to-be-adhered body is improved, It has also been found in the present inventors' study that use results in a decrease in adhesion (initial adhesion).

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a solid adhesive having a good applicability to an adherend and improved initial adhesiveness and a raw material liquid composition for preparing such a solid adhesive. have.

The solid adhesive of the present invention obtained by achieving the above object comprises a component derived from a water-soluble adhesive polymer and an aqueous polymer emulsion, wherein the solid content of the component derived from the aqueous polymer emulsion is the water-soluble adhesive polymer and the aqueous polymer. It is a summary that it is 0.01-30 mass% with respect to the total amount of solid content of the component derived from an emulsion.

The present inventors have found that in a solid adhesive comprising a water-soluble adhesive polymer as a main component of an adhesive component, by blending a specific amount of an aqueous polymer emulsion, the initial adhesive property can be improved without impairing the applicability to the adherend. Came to complete.

Hereinafter, the structure of the solid adhesive of the present invention will be described in detail.                     

The main component of the adhesive component of the solid adhesive is a water-soluble adhesive polymer. The polymer particles contained in the aqueous polymer emulsion, which is one of the components of the solid adhesive, can also contribute as an adhesive component.However, when the polymer in the aqueous polymer emulsion becomes the main component of the adhesive component, the solid adhesive tends to soften. Since oil-retaining property is impaired, application to a to-be-adhered body falls, for example, it becomes difficult to apply as stick glue.

In such a case, in order to prevent softening of the solid adhesive, it is necessary to use a large amount of the gelling agent described later, but this causes a problem of deterioration of adhesiveness.

Therefore, in the present invention, the main component of the adhesive component is a water-soluble adhesive polymer, and the amount of the water-soluble adhesive polymer in the solid adhesive is required to be larger than the solid content (substantially equivalent to the polymer particle amount) of the component derived from the aqueous polymer emulsion. Specifically, the solid content of the component derived from the aqueous polymer emulsion is 0.01 mass% or more and 30 mass% or less with respect to the total amount of the solid content of the water-soluble adhesive polymer and the component derived from the aqueous polymer emulsion.

In addition, in this invention, solid content of the component derived from an aqueous polymer emulsion refers to the non volatile matter which can be obtained when these aqueous polymer emulsions are dried at 110 degreeC under normal pressure for 2 hours.

When the solid content of the component derived from the aqueous polymer emulsion exceeds the above range, the hardness of the solid adhesive tends to decrease as described above, and the applicability to the adherend is reduced. In order to avoid such a problem, when using the gelation agent mentioned later in large quantity, initial stage adhesiveness will fall. In addition, the solid adhesive of the present invention can be obtained, for example, by mixing and heating each raw material as a liquid substance in which viscosity is adjusted, and filling it into a container (such as a lipstick) and cooling and solidifying it, but it is derived from an aqueous polymer emulsion. If the solid content of the component exceeds the above range, the viscosity of the liquid before filling into the container increases, and the problem of taking a long time to take out of the container or to fill a relatively small lipstick-shaped container of 1 cm to several cm is also required. Occurs. In addition, when the solid content of the component derived from the aqueous polymer emulsion exceeds the above range, the coloring of the solid adhesive becomes remarkable, and the appearance problem also occurs.

On the other hand, when the solid content of the component derived from the aqueous polymer emulsion is less than the above range, the application effect of the aqueous polymer emulsion may not be sufficiently secured. The solid content of the component derived from the aqueous polymer emulsion is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, preferably 25% by mass or less, based on the total amount of the solid content of the water-soluble adhesive polymer and the component derived from the aqueous polymer emulsion. More preferably, it is 20 mass% or less.

Examples of the water-soluble adhesive polymers include polymers polymerized with monomer components containing N-vinyllactam as essential components; polyvinyl alcohol and vinyl alcohol copolymers; polyurethane and urethane copolymers; polyacrylic acid and acrylic acid copolymers, and these Salts of modified polysaccharides such as hydroxyethyl starch, hydroxypropyl starch, hydroxyethyl cellulose and carboxymethyl cellulose; These etc. are mentioned, These can also be used individually by 1 type or in mixture of 2 or more types.

Among these, polymers, polyvinyl alcohols, and air prepared by polymerizing a monomer component containing N-vinyl lactam as an essential component in terms of good adhesiveness and sufficient shape retention even in a small amount of the gelling agent described later can be ensured. Copolymers (particularly polyvinyl alcohol) and modified polysaccharides are preferred, and polymers obtained by polymerizing monomer components containing N-vinyllactam as essential components are particularly preferred.

Specific examples of N-vinyllactam usable for polymers obtained by polymerizing monomer components containing N-vinyllactam as essential components include N-vinylpyrrolidone, N-vinyl-5-methyl-2-pyrrolidone, and N- Vinyl-2-piperidone, N-vinyl-6-methyl-2-piperidone, N-vinyl-ε-caprolactam, N-vinyl-7-methyl-ε-caprolactam, and the like. Species or two or more species may be used. N-vinylpyrrolidone is most preferred in view of adhesion and availability.

Examples of monomers that can be used when synthesizing the water-soluble adhesive polymer other than N-vinyl lactam include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and stearyl (meth) acrylate. (Meth) acrylic acid alkyl esters such as; (meth) acrylic acid or salts thereof; amino group-containing monomers such as dimethylaminoethyl (meth) acrylate and dimethylaminopropyl (meth) acrylate; (meth) acrylonitrile; (meth) acrylamide Amide group-containing monomers such as N-methylol acrylamide, vinyl acetamide, and vinyl formamide; vinyl ethers such as vinyl acetate; styrene; methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, and isobutyl vinyl ether; C2-C30 alpha-olefin, These can use 1 type, or 2 or more types. However, it is preferable to suppress these monomers other than N-vinyl lactam to 50 mass% or less in 100 mass% of monomer components. It is because the water solubility and the outstanding adhesiveness of the polymer derived from N-vinyl lactam can also be reduced.

As mentioned above, among the polymers which superpose | polymerize the monomer component containing N-vinyl lactam as an essential component, polyvinylpyrrolidone or a vinylpyrrolidone copolymer is more preferable, and polyvinylpyrrolidone is the most preferable.

In a polymer obtained by polymerizing a monomer component containing N-vinyllactam as an essential component, K is obtained from Equation 1 using a relative viscosity value (25 ° C.) measured by a capillary viscometer as an aqueous solution of concentration: 1% by mass. The larger the value is, the higher the adhesive strength of the solid adhesive is, the K value is preferably 50 or more, more preferably 70 or more, and even more preferably 80 or more.

[Equation 1]

η _{re ㅣ} : relative viscosity of water in polymer solution

c: polymer concentration (mass%) in the polymer aqueous solution

In addition, in a water-soluble adhesive polymer (not limited to a polymer obtained by polymerizing a monomer component containing N-vinyllactam as an essential component), the concentration is 25 by using a b-type viscometer (spindle No. 2) as an aqueous solution of 10% by mass. It is preferable that the adhesive force of a solid adhesive is high, so that the viscosity which can be obtained by measuring at degreeC is large, It is preferable that it is 30 mPa * S or more, It is more preferable that it is 70 mPa * S or more, It is still more preferable that it is 100 mPa * S or more.

In addition, water-soluble adhesive polymers (particularly polymers obtained by polymerizing monomer components containing N-vinyllactam as essential components) are generally expensive and occupy most of the raw material cost of the solid adhesive, but in the present invention, inexpensive aqueous polymer In order to improve the adhesiveness by applying an emulsion, when securing the same level of adhesiveness as in the prior art, it is also advantageous to reduce the cost of water-soluble adhesive polymer by reducing the cost.

The aqueous polymer emulsion used in the present invention refers to an emulsion in which polymer particles are uniformly dispersed in a medium containing water. The aqueous polymer emulsion preferably has a minimum film forming temperature (MFT) of 30 ° C or lower. It is because the adhesiveness in normal temperature of a solid adhesive may fall when MFT exceeds such an upper limit. As for MFT of an aqueous polymer emulsion, it is more preferable that it is 25 degrees C or less, and it is still more preferable that it is 20 degrees C or less. In addition, MFT here is a value measured by the following method. The MFT is determined by applying an aqueous polymer emulsion to a glass plate placed on a thermal gradient tester with a 0.2 mm gap applicator and measuring the temperature at which the crack has occurred. This temperature is the lowest temperature at which a continuous film is formed without cracks.

For example, an aqueous polymer emulsion having an MFT of 30 ° C. or less can be prepared on the basis of using polymer particles having a glass transition temperature (Tg) of 40 ° C. or less. It is because MFT is known to be 10 degreeC lower than Tg (degreeC) generally. Tg (K) is obtained by simply calculating the Tg (K) based on the Tg (K) of each homopolymer described in "POLYMER HANDBOOK 3rd Edition" (issued by John WiLLey & Sons, Inc.). It can also be obtained by differential scanning calorimetry (TMA) or TMA (thermomechanical measuring device). Moreover, even if it is a polymer particle with a high Tg, it is also possible to adjust MFT below the said upper limit by making it an aqueous polymer emulsion using the plasticizer mentioned later.

The resin (polymer particles) of the aqueous polymer emulsion is not particularly limited as long as it is a resin employed in the field of adhesives, and conventional resins can be used. That is, the aqueous polymer emulsion includes vinyl acetate-based polymers such as polyvinyl acetate and vinyl acetate copolymer; Acrylic polymers such as poly (meth) acrylic acid ester and acrylic acid ester-methacrylic acid ester copolymers; urethane-based polymers such as polyurethane; And polymer emulsions containing, for example, the main component of the polymer particles. Moreover, the alkali-soluble emulsion which can make a (meth) acrylic acid ester- (meth) acrylic acid copolymer the main component of a polymer particle can also be used. These aqueous polymer emulsions may be used alone or in combination of two or more thereof. Of these, emulsions of vinyl acetate-based polymers are recommended in view of good adhesion to paper, which is one of the main adherends of the solid adhesive of the present invention.

Examples of the vinyl acetate polymers include copolymers of vinyl acetate with other monomers, in addition to polyvinyl acetate (homopolymer of vinyl acetate). Examples of the other monomer copolymerizable with vinyl acetate include olefins such as ethylene; ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, and 2- (meth) acrylic acid. (Meth) acrylic acid alkyl esters, such as ethyl exel; vinyl esters except vinyl acetate, such as vinyl propionate, vinyl caprylate, vinyl caproate, and vinyl basatic acid; diethyl maleate, dibutyl maleate, dioctyl maleate, and maleic acid 2 Maleic acid esters such as ethylhexyl; fumaric acid esters such as diethyl fumarate, dibutyl fumarate, dioctyl fumarate and 2-ethylhexyl fmarate; These etc. can be mentioned and these can use 1 type (s) or 2 or more types.

Among the vinyl acetate-based polymers obtained by using the above monomers, polyvinyl acetate is preferable in that adhesiveness to paper, which is one of the main adherends of the solid adhesive of the present invention, is good.

In addition, the emulsion of the vinyl acetate polymer may contain a known emulsifier, a protective colloid, a plasticizer (dibutyl phthalate, dioctyl phthalate, or the like).

The aqueous polymer emulsion can be prepared by a known method. For example, the method of emulsion-polymerizing the said monomer by water system and the method of disperse | distributing (emulsification) the said resin obtained by superposing | polymerizing separately in the medium containing water are mentioned. In addition, it is common that the solid content concentration of an aqueous polymer emulsion is 20-70 mass%.

In the above-mentioned aqueous polymer emulsion, the particle diameter of the polymer particles is not particularly limited as long as the effects of the present invention are not impaired. For example, the average particle diameter is preferably 0.001 to 10 µm.

In the solid adhesive of the present invention, a gelling agent is also a component in order to secure shape retention. The said gelling agent is not specifically limited, The well-known gelling agent conventionally used for a solid adhesive conventionally can be used. For example, metal salt or ammonium salt of C8-C36 fatty acid, such as laurate, myristicate, palmitate, stearic acid salt, and ricinoleate; sorbitan benzaldehyde condensate, xyrite benzaldehyde condensate, etc. Condensates of sugar alcohols having 4 or more carbon atoms with aromatic aldehydes; Etc. can be mentioned. Especially, the alkali metal salt or ammonium salt of a C8-C36 fatty acid is preferable, and an alkali metal salt is more preferable. Moreover, as alkali metal in the metal salt of a C8-C36 fatty acid, Na, K, etc. are common.

By the way, although the solid adhesive of this invention is excellent in the applicability | paintability to an to-be-adhered body and initial adhesiveness, the obtained product may remarkably color. In such a case, the product value of the solid adhesive may be impaired, the use thereof may not be beneficial depending on the type of adherend, and the appearance of the adherend after application may be impaired.

In the above-described problem of coloring, the inventors have investigated that coloring of the solid adhesive becomes remarkable by heating at the time of production, when the component contains a component derived from an aqueous polymer emulsion together with a water-soluble adhesive polymer as a component. However, in order to improve the initial adhesiveness, the component derived from an aqueous polymer emulsion is an important component. As a result of a new review, when an inorganic reducing substance is further employed as a component of a solid adhesive comprising a water-soluble adhesive polymer and a component derived from an aqueous polymer emulsion, the characteristics as a solid adhesive, for example, It has been found that the coloring of the solid adhesive can be prevented without impairing the applicability or initial adhesion of the adhesive. Therefore, the solid adhesive of the present invention preferably further comprises an inorganic reducing substance as a component.

In the solid adhesive of the present invention, an inorganic reducing substance is particularly preferable because the organic reducing substance may not have a color suppression effect, and the coloring of the solid adhesive may be enhanced by heating at the time of manufacture.

As the inorganic reducing substance, for example, sulfites such as sodium sulfite, potassium sulfite, sodium bisulfite, sodium hyposulfite and calcium sulfite, sulfur dioxide, sodium thiosulfate and the like can be preferably used. Among these, sulfite is preferable because of its high color inhibitory effect and excellent safety. More preferred is sodium sulfite.

The amount of the inorganic reducing substance is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more based on 100 parts by mass of the total amount of solids of the component derived from the water-soluble adhesive polymer and the aqueous polymer emulsion. When the compounding quantity of an inorganic reducing substance satisfy | fills the said lower limit, the effect of reducing the coloring of a solid adhesive is especially effective.

In addition, the upper limit of the amount of the inorganic reducing substance is not particularly limited, but is preferably 40 parts by mass or less, more preferably 20 parts by mass or less with respect to 100 parts by mass of the total amount of solids of the component derived from the water-soluble adhesive polymer and the aqueous polymer emulsion. . The solid adhesive of the present invention can be obtained, for example, by mixing and heating each raw material into a liquid substance having a controlled viscosity, and filling it into a container (such as a lipstick) and cooling and solidifying the same. When the upper limit is exceeded, the viscosity of the liquid before filling into the container increases, and the filling operation into a relatively small lipstick-shaped container of 1 cm to several cm tends to take time.

The fineness of coloring of a solid adhesive can be evaluated by the b value obtained by measuring the Lab color difference (color difference by CIE Lab color difference formula based on JIS Z 8730 standard) of a solid adhesive using a spectrophotometer. In addition, b value shows that yellowness is strong, and solid adhesive is coloring, and when b value is 3.5 or less, it is a range acceptable as a white solid adhesive.

In the preparation of the solid adhesive, the water-soluble adhesive polymer, the gelling agent, and the aqueous polymer emulsion (and, if necessary, an inorganic reducing substance) are dissolved and dispersed in an aqueous solvent and filled into a container for the solid adhesive composition. . Although water is preferable as an aqueous solvent, In an aqueous solvent, Alcohol, such as ethanol and isopropyl alcohol; Ketones such as methyl ethyl ketone; Ester, such as ethyl acetate, may be included. Moreover, the whole quantity of the said aqueous solvent may be the medium (media containing water) of an aqueous polymer emulsion.

It is preferable to mix | blend polyhydric alcohol, in order to act as a dissolving aid for dissolving a gelling agent in an aqueous solvent, and to act as a humectant and a plasticizer. For example, dihydric alcohols, such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetramethylene glycol; And trihydric or higher alcohols such as glycerin, trimethylolpropane and pentaerythritol. In addition, cyclic alcohols such as ketose (hexose, heptose, etc.), aldonic acid, aldalic acid, deoxysaccharides, and inomitol sugars can also be used.

In the solid adhesive of the present invention, the amount of the gelling agent is preferably 10 parts by mass or more, more preferably 15 parts by mass or more based on 100 parts by mass of the total amount of solids of the component derived from the water-soluble adhesive polymer and the aqueous polymer emulsion. Preferably it is 80 mass parts or less, More preferably, it is recommended to use 65 mass parts or less. If the amount of the gelling agent is less than the above range, the shape retaining property of the solid adhesive tends to be lowered, and the above-described problems may occur with this. On the other hand, when the amount of gelling agent exceeds the said range, initial stage adhesiveness may fall.

The amount of the aqueous solvent in the solid adhesive is preferably 100 parts by mass or more, more preferably 150 parts by mass or more, with respect to 100 parts by mass of the total amount of solids of the water-soluble adhesive polymer and the component derived from the aqueous polymer emulsion. It is preferable to set it as 500 mass parts or less, More preferably, it is 400 mass parts or less. In addition, when using the organic solvent as illustrated above in addition to water as an aqueous solvent, it is preferable to make this organic solvent 10 mass% or less in 100 mass% of aqueous solvents, and it is more preferable to set it as 5 mass% or less. Do. sure. It is also preferable that the whole amount of the aqueous solvent is water.

Moreover, when using the said polyhydric alcohol, it is preferably 5 mass parts or more, More preferably, it is 10 mass parts or more, Preferably it is 150 mass parts with respect to 100 mass parts of total amounts of solid content of the said water-soluble adhesive polymer and the component derived from an aqueous polymer emulsion. It is preferable to set it as 100 mass parts or less more preferably.

The solid adhesive composition of the present invention may be formed by adding other known additives. As such an additive, For example, water-soluble polymers, such as a polyalkylene glycol, a polyalkylene oxide, a polyalkylene imine; Fats and oils such as linseed oil, lysine, castor oil, soybean oil, palm oil, tor oil, fish oil, oleic acid, linoleic acid and linoleic acid; Polyoxyalkylene ether, polyoxyalkylene fatty acid ester, polyoxyalkylene sorbitan (mono, di, tri) fatty acid ester, (poly) glycerin (mono, di, tri) fatty acid ester, sorbitan (mono, di, Surfactants such as tri) stearate; Lubricants such as liquid paraffin; Inorganic extenders such as silica, alumina, titanium dioxide, barium oxide, zinc oxide, talc and bentonite; Sugars such as sucrose and sorbitol; Dextrin, such as dextrin and cyclodextrin, etc. are mentioned, A suitable amount can be used as needed. In addition, fragrances, fluorescent brighteners, antibacterial agents, preservatives, coloring agents and the like can be blended. For example, it is recommended to add about 0.01 to 0.1 mass% of antibacterial agent in solid adhesive.

As a specific manufacturing method of a solid adhesive, the following method can be employ | adopted, for example. The aqueous solvent (preferably water) is mixed with the water-soluble adhesive polymer and the aqueous polymer emulsion (or inorganic reducing substance, if necessary), and then the mixture is stirred while heating to give a uniform dispersion (ie, the solid form of the present invention). A raw material liquid composition for an adhesive) is prepared, and a gelling agent and a polyhydric alcohol are mixed and uniformly dissolved therein as necessary, and various additives are mixed as necessary to obtain a liquid having a viscosity adjusted. Such a liquid is filled into a container (for example, a lipstick, etc.), cooled and solidified to obtain a solid adhesive. However, the addition order of each raw material is not specifically limited, You may add and mix each raw material in the order of that excepting the above. In addition, when the whole quantity of an aqueous solvent is used as the medium derived from an aqueous polymer emulsion, of course, it is not necessary to use an aqueous solvent separately.

In addition, a raw material liquid composition for a solid adhesive is prepared in advance. For example, a water-soluble adhesive polymer, a gelling agent, a polyhydric alcohol, and various additives are mixed with such a raw material liquid composition again to give the above-mentioned viscosity-controlled liquid material. It is good also as a solid adhesive by one method. In this case, the raw material liquid composition for a solid adhesive has a content of a water-soluble adhesive polymer (preferably a polymer obtained by polymerizing a monomer component containing N-vinyllactam as an essential component) of 1% by mass or more, preferably 5% by mass or more. , 40 mass% or less, preferably 30 mass% or less, and the solid content of the component derived from the aqueous polymer emulsion is 0.01 mass% or more, preferably 0.05 mass% or more, more preferably 0.1 mass% or more, 50 It is preferable to set it as mass% or less, Preferably it is 40 mass% or less, More preferably, it is 30 mass% or less. When the raw material liquid composition is used, it is possible to easily prepare a solid adhesive. If both the water-soluble adhesive polymer and the solid content of the component derived from the aqueous polymer emulsion exceed the above ranges, the viscosity of the raw material liquid composition becomes large and handling becomes difficult, and below the above ranges, the adjustment of the amount of each component for producing the solid adhesive of the present invention is complicated. Done.

Moreover, although the preferable range of each component amount of a raw material liquid composition and the preferable range of each component amount of a solid adhesive do not correspond, this is a case where a solid adhesive is prepared by mixing a water-soluble adhesive polymer with a raw material liquid composition further as mentioned above. Because there may be.

In addition, when the raw material liquid composition for a solid adhesive contains an inorganic reducing substance, the compounding quantity of an inorganic reducing substance is preferably 0.001 mass part with respect to 100 mass parts of total amounts of solid content of the said water-soluble adhesive polymer and the component derived from an aqueous polymer emulsion. As mentioned above, More preferably, it is 0.01 mass part or more, Preferably it is 40 mass parts or less, More preferably, it is recommended that it is 20 mass parts or less. When the amount of the inorganic reducing substance is less than the above range, the effect of suppressing the coloring of the solid adhesive may be reduced. On the other hand, when an inorganic reducing substance is added in excess of the above range, the viscosity of the raw material liquid composition may be sag, making handling difficult.

In addition to the color suppression of the solid adhesive, the inorganic reducing substance also has an effect of preventing the viscosity decrease of the raw material liquid composition for the solid adhesive during storage. The decrease in viscosity of the raw material liquid composition causes a decrease in the adhesive strength of the solid adhesive prepared by using the same. However, by adding an inorganic reducing substance, the above problem can be prevented and a solid adhesive having good adhesion can be obtained.

In addition, by mixing the inorganic reducing substance with the raw material liquid composition in advance, it is possible to prevent coloring of the raw material liquid composition at the time of storage. Thus, the inorganic reducing substance is also useful for ensuring the stability of the raw material liquid composition at the time of storage.

Preferred adherends to be subjected to the solid adhesive of the present invention include known papers such as paper, synthetic paper, fine paper, heavy paper, art paper, coated paper, cast coated paper, foil paper, kraft paper, impregnated paper, and deposition paper; Polyester films (including sheets) such as terephthalate and polybutylene terephthalate; woven or nonwoven fabrics made of fibers such as cotton, polyester, and nylon; various kinds of yarns; aluminum foil, copper foil and the like.

EXAMPLE

Hereinafter, the present invention will be described in detail with reference to Examples. However, the following examples are not intended to limit the present invention, and any modifications made within the scope not departing from the gist of the foregoing or later will be included in the technical scope of the present invention. "'" And "%" are mass references | standards unless there is particular limitation. In addition, the evaluation method used in a present Example is as follows.

(1) adhesion time

The following experiment was performed in the atmosphere of the temperature of 25 degreeC, and 60% of a relative humidity. Usually, copy paper (PPC paper) is cut into 3cm × 6cm to make test paper. Immediately after applying the solid adhesive to one half of the one-sided surface of the test paper, the test paper is overlapped and fitted. After the predetermined time has elapsed from the pasting time, the non-adhesive portions of the test paper put together and pulled together are peeled off in different directions. In the state where the test paper was put together, the time was taken as the adhesion time until the test paper was not torn and peeled off. The shorter the adhesion time means that the adhesive force is exhibited in a short time in the bonded state, that is, the initial adhesion is excellent.

(2) coating

Under an atmosphere of 25 ° C temperature and 60% relative humidity, a 1 Kg load is applied to one side bottom of a cylindrical adhesive having a diameter of 23 mm, and the other bottom is usually placed on a copy paper, and the copy paper is towed horizontally at a speed of 10 mm / sec. The degree of form collapse of the solid adhesive when evaluated was visually evaluated. Evaluation criteria are as follows.

○: no form collapse

△: form collapse.

X: Form collapse is large and application | coating is impossible.

(3) Measurement of whiteness (b value)                     

The Lab color difference (color difference by CIE Lab color difference formula prescribed | regulated to JIS Z 8730) of the solid adhesive obtained by the following experiment was measured using the spectroscopic color difference meter (SE-2000 by Nippon Color Industry Co., Ltd.). Whiteness shown in Tables 3-5 is evaluated using b value.

(4) measurement of viscosity

70 g of the raw material liquid composition for the solid adhesive was placed in a 100 mL beaker and immersed in a constant temperature bath at 25 ° C. for 3 hours, and the viscosity was measured at a rotational speed of 3 rPm using a b-type viscometer (spindle No. 3).

<Experiment 1>

The water-soluble adhesive polymer used in this experiment is polyvinylpyrrolidone ("K85" by the Japanese catalyst company), or hydroxypropyl starch ("HDV" by the sorbitol company). The K value obtained by the above-mentioned method for this polyvinylpyrrolidone was 83, the 10% aqueous solution viscosity determined by the above-mentioned measuring method was 290 mPa * S, and the weight average molecular weight by gel permeation chromatography (polystyrene conversion) was about 100. It was only. Moreover, about this hydroxypropyl starch, the 10% aqueous solution viscosity calculated | required by the above-mentioned measuring method was 300 mPa * S.

The aqueous polymer emulsion used in this experiment is a polyvinyl acetate emulsion ("vinibran 1107L" manufactured by Ilshin Chemical Co., Ltd.) having a solid content concentration of 50%. The MFT measured by the method mentioned above about this polyvinyl acetate emulsion is 2 degreeC.

Experimental Example 1-1

59.0 parts of water and 1.0 part of said polyvinyl acetate emulsion were added to the flask provided with the reflux condenser and the stirrer, and it heated up at 80 degreeC, stirring. Thereafter, 26.0 parts of the above polyvinylpyrrolidone was added little by little so as not to be bent to dissolve to obtain a raw material liquid composition. Next, 7.0 parts of glycerin and 7.0 parts of sodium stearate (gelling agent) were added, it stirred for 24 hours, and the white liquid substance which adjusted the viscosity was obtained. After heating this liquid substance to 90 degreeC, it filled in the lipstick container (diameter: 23 mm, length: 80 mm), left to cool, it solidified, and obtained the solid adhesive. The composition of each raw material of this solid adhesive and its evaluation results are shown in Table 1.

Experimental Examples 1-2 to 1-9

Except having changed the compounding composition of each raw material as shown in Table 1, it carried out similarly to Experimental Example 1-1, and obtained the solid adhesive. The evaluation results of the obtained solid adhesive are shown in Table 1. In addition, the solid adhesive of Experimental Example 1-6 and Experimental Example 1-7 does not use the said polyvinyl acetate emulsion, and is equivalent to the conventional polyvinylpyrrolidone type solid adhesive.

TABLE 1

In the formula composition column of Table 1, "polyvinyl acetate emulsion (solid content)" indicates the solid content in the polyvinyl acetate emulsion, and "water" shows the total amount of water in the polyvinyl acetate emulsion and the water used separately. . In addition, the column of "solid amount derived from a polyvinyl acetate emulsion" shows the quantity with respect to the total amount of the polyvinyl pyrrolidone in the solid adhesive and the solid content of the component derived from a polyvinyl acetate emulsion.

In addition, in the column of "Adhesion time" of Table 1, each evaluation of "(circle), (circle), (triangle | delta), x" is made into the reference | standard (△) based on the adhesion time of the solid adhesive of Experimental example 1-6 corresponding to a prior art example. This is judged by comparison with this. That is, "◎" that the adhesion time is significantly shorter than the adhesion time of the solid adhesive of Experimental Example 1-6, "○" that the adhesion time is shortened, "○", and that the adhesion time is prolonged for "x" It was. In addition, the comprehensive evaluation of Table 1 was based on the solid adhesive of Experimental Example 1-6 corresponding to the prior art as the reference (△), and the characteristics (adhesive time, coating property) of the other solid adhesives were used as Experimental Example 1-. It is compared with the solid adhesive of 6, and then judged relatively. That is, when at least one of the above characteristics is superior to the solid adhesive of Experimental Example 1-6, and the remaining characteristics are equivalent to Experimental Example 1-6, "○" and at least one of the above characteristics are Experimental Example 1-6 When it was inferior to the solid adhesive of, it was set as "x."

As can be seen from Table 1, the solid adhesives of Experimental Examples 1-1 to 1-5 were very suitable amounts of solids of polyvinyl acetate emulsion, and both of the initial adhesiveness and the coating property were excellent. Particularly, in Experimental Example 1-1, when excellent initial adhesiveness was achieved, Experimental Examples 1-2 and 1-5 reduced costly polyvinylpyrrolidone, but had superior adhesiveness than the conventional example (Experimental Example 1-6). The cost reduction of the solid adhesive is achieved by ensuring that the adhesion time of the solid adhesive of Experimental Example 1-2 is 195 seconds, and the bonding time of the solid adhesive of Experimental Example 1-6 is 210 seconds. Although the difference with is seen to be small at first glance, assuming a mode of use when sticking paper using a stick paste (solid adhesive), the time required to achieve effective adhesion is reduced by 15 seconds It is obvious that the efficiency rises significantly. Therefore, it can be judged that the solid adhesive of Experimental Example 1-2 has the initial stage adhesiveness superior to the solid adhesive of Experimental Example 1-6.

On the other hand, Experimental Example 1-7 is an example in which the amount of polyvinylpyrrolidone used is reduced in the same manner as in Experimental Examples 1-2 to 1-5, but since the polyvinyl acetate emulsion is not used, the initial adhesive property is inferior.

In addition, Experimental Example 1-8 is an example in which the usage-amount of polyvinyl acetate emulsion is too much, shape retention property is impaired, and coating property is extremely inferior. Therefore, the adhesion time was not measured.

Example 1-9 is an example in which the amount of gelling agent is increased with respect to the amount of water-soluble adhesive polymer in order to improve the applicability decrease in Experimental Example 1-8, thereby improving the rigidity (ie, shape retaining property) of the solid adhesive. Here, although applicability | paintability and mold filling property are favorable, initial stage adhesiveness is extremely inferior.

Experimental Example 1-10

A solid adhesive was obtained in the same manner as Experimental Example 1-1 except that the water-soluble adhesive polymer was changed to the hydroxypropyl starch. The evaluation results of this solid adhesive are shown in Table 2.

Experimental Example 1-11                     

A solid adhesive was obtained in the same manner as Experimental Example 1-10 except that the polyvinyl acetate emulsion was not used. That is, the solid adhesive of Experimental Example 1-11 does not use polyvinyl acetate emulsion, and is equivalent to the conventional hydroxypropyl starch-based solid adhesive. The evaluation results of this solid adhesive are shown in Table 2.

TABLE 2

In the formula composition column of Table 2, "polyvinyl acetate emulsion (solid content)" indicates the solid content in the polyvinyl acetate emulsion, and "water" shows the total amount of water in the polyvinyl acetate emulsion and water used separately. . In addition, the column of "solid amount derived from polyvinyl acetate emulsion" shows the quantity with respect to the total amount of the hydroxypropyl starch in solid adhesive and the solid content of the component derived from polyvinyl acetate emulsion.

In addition, in the column of "Adhesion time" of Table 2, each evaluation of "(circle) and (triangle | delta)" shortens adhesion time based on the adhesion time of the solid adhesive of Experimental example 1-11 corresponding to a prior art example ((triangle | delta)). What was set as "(circle)".

As can be seen from Table 2, the solid adhesive of Experimental Example 1-10 containing the solid content of the polyvinyl acetate emulsion in a suitable amount is applicable compared to the solid adhesive of Experimental Example 1-11 corresponding to the conventional example. The initial adhesive property is improved without this damage.

<Experiment 2>

The water-soluble adhesive polymers used in this experiment were polyvinylpyrrolidone (Experimental Examples 2-1 to 2-7: "K85" manufactured by Nippon Catalyst Co., Ltd., K value 85), and polyvinyl acetate having a solid content concentration of 50% as an aqueous polymer emulsion. An emulsion ("Viniburan 1107L" by Ilshin Chemical Co., Ltd.) was used.

Experimental Example 2-1

54.6 parts of water and 8.0 parts of said polyvinyl acetate emulsions were added to the flask provided with the reflux condenser and the stirrer, and it heated up at 80 degreeC, stirring. Thereafter, 23.4 parts of the polyvinylpyrrolidone was added and dissolved little by little so as not to bend, and sodium sulfite: 1.0 part was added thereto to prepare a raw material liquid composition. Next, 6.0 parts of glycerin and 7.0 parts of sodium stearate (gelling agent) were added thereto, and the mixture was stirred for 24 hours to obtain a white liquid substance in which viscosity was adjusted. After heating up this liquid substance at 90 degreeC, it filled in the lipstick container (23 mm in diameter, 80 mm in length), and left it to stand by cooling solidification, and obtained the solid adhesive. Each raw material composition of this solid adhesive and the evaluation result are shown in Table 3.

Experimental Examples 2-2 to 2-5

Except having changed the compounding composition of each raw material as shown in Table 3, it carried out similarly to Experimental Example 2-1, and obtained the solid adhesive. The evaluation results of the obtained solid adhesive are shown in Table 3. In addition, the solid adhesive of Experimental Example 2-1 and 2-2 shows the example which used an inorganic reducing substance, and Experimental Example 2-4 and 2-5 used the organic reducing substance, respectively, and Experimental Example 2-3 shows a reducing substance The example which does not use is shown.                     

TABLE 3

In the formula composition column of Table 3, "polyvinyl acetate emulsion (solid content)" shows the solid content in polyvinyl acetate emulsion, and "water" shows the total amount of water in polyvinyl acetate emulsion and the water used separately. .

As can be seen from Table 3, the whiteness (b value) of the solid adhesives of the Experimental Examples 2-1 and 2-2 using the inorganic reducing substance was determined by the solid adhesion of the Experimental Example 2-3 containing no reducing substance. It is smaller than that, and color suppression effect can be obtained. In particular, the b value of the solid adhesive of Experimental Example 2-1 using sodium sulfite as the inorganic reducing substance was very small (b value: 0.7), and excellent color suppression effect was obtained.

On the other hand, b value of the solid adhesive of Experimental Examples 2-4 and 2-5 using an organic reducing substance is equivalent to the value of the solid adhesive of Experimental Example 2-3 without using a reducing substance (Experimental Example 2-4). , Or large (Experimental Example 2-5), it is not only possible to suppress the coloring, but also it can be seen that the solid adhesive remarkably colored, especially the high of Experimental Example 2-5 using sodium L-ascorbate The b value of the shape adhesive is large (b value: 14.9), and is colored remarkably.                     

Experimental Example 2-6, 2-7

A raw material liquid composition for a solid adhesive was prepared in the same manner as in Experiment 2-1, except that the composition of each raw material was changed as shown in Table 4. The obtained raw material liquid composition was placed in a glass sample tube under an air atmosphere, sealed, shielded, and stored at 60 ° C. for 3 weeks to evaluate the storage stability of the raw material liquid composition. Here, evaluation was performed by comparing the whiteness before and after the storage of the liquid composition. The evaluation results of these raw liquid compositions are shown in Table 4.

TABLE 4

The raw material composition solution of Experimental Example 2-6 containing sodium sulfite as an inorganic reducing substance has little decrease in whiteness before and after storage, and hardly causes a decrease in viscosity even under severe conditions as described above, and is excellent in storage stability. On the other hand, the raw material composition of Experimental Example 2-7, which does not contain sodium sulfite, is significantly unsatisfactory after being preserved under the above conditions and the viscosity is drastically reduced. Thus, it is unsatisfactory to use the raw material solution as a solid adhesive.

 The present invention is constituted as described above, and by incorporating a specific amount of an aqueous polymer emulsion into a solid adhesive comprising a water-soluble adhesive polymer as the main component of the adhesive component, the initial coating is carried out while maintaining good applicability (shape retention) to the adherend. Adhesion could be improved.

Claims (5)

It comprises a water-soluble adhesive polymer, a component derived from an aqueous polymer emulsion, and an inorganic cyclic material as a component, Solid content of the component derived from the said aqueous polymer emulsion is 0.01-22.8 mass% with respect to the total amount of solid content of the said water-soluble adhesive polymer and the component derived from the said aqueous polymer emulsion, The amount of said inorganic reducing substance is 0.001-40 mass% with respect to 100 mass parts of total amounts of solid content of the said water-soluble adhesive polymer and the component derived from the said water-based polymer emulsion. delete The solid adhesive according to claim 1, wherein the aqueous polymer emulsion has a minimum film temperature of 30 ° C or less. The solid adhesive according to claim 1, wherein the water-soluble adhesive polymer comprises a polymer obtained by polymerizing a monomer component containing N-vinyllactam as an essential component. Raw material liquid composition for preparing the solid adhesive according to claim 1, The component includes a water-soluble adhesive polymer, a component derived from an aqueous polymer emulsion, and an inorganic reducing substance, Content of the said water-soluble adhesive polymer is 1-40 mass%, Solid content of the component derived from the said aqueous polymer emulsion is 0.01-50 mass%, A solid adhesive raw material liquid composition, wherein the amount of the inorganic reducing substance is 0.001 to 40% by mass based on 100 parts by mass of the total amount of solids of the water-soluble adhesive polymer and the component derived from the aqueous polymer emulsion.