JP2013108047A - Water-soluble paste composition for surface processing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-soluble paste which can be used in a plastic working or surface processing process that requires a small number of treatment steps, is easy and excellent in selection accuracy, and can reduce production cost, with respect to a plastic working or surface processing process which is widely used in a process of producing a semiconductor element of a display device or a solar cell.SOLUTION: A water-soluble paste composition for plastic working or surface processing contains (A) a water-soluble polymer, (B) a surfactant, and (C) at least one selected from the group consisting of an inorganic substance fine particle and an organic substance fine particle.

Description

The present invention relates to a water-soluble paste composition for surface processing.

  In recent years, electronic devices such as liquid crystal display elements, organic EL elements, distributed EL elements, electronic paper elements, and other various types of displays have been accelerating the movement of lightness and thinning. High-function mobile phones equipped with electronic components (hereinafter referred to as touch panels) combined with position input devices are rapidly spreading.

In addition, the development of clean energy sources is desired due to the problem of depletion of energy resources and global environmental problems such as an increase in CO _{2 in} the atmosphere. In particular, solar power generation using solar cells is a new energy source. It has been developed and put into practical use.

A transparent conductive film and a flexible wiring board are used for the various functional display devices and solar cells described above. As these examples, in general, a transparent conductive layer (hereinafter referred to as “sputtering ITO layer”) of indium tin oxide (hereinafter referred to as “ITO”) using a physical film forming method such as sputtering or ion plating. A plastic film (hereinafter abbreviated as “sputtering ITO film”) or a film in which a metal thin film is bonded to a plastic film is widely known.

For example, the sputtering ITO film has a thickness of an ITO single layer, which is an inorganic component, formed on a transparent plastic film such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN) as a base film by the physical vapor deposition method. Is formed so as to have a thickness of about 20 to 50 nm, whereby a low-resistance transparent conductive layer having a surface resistance value of about 100 to 300 Ω / □ can be obtained.

However, the sputtered ITO layer is a thin film of an inorganic component and is extremely brittle, so that there is a problem that microcracks (cracks) are likely to occur. Specifically, when a sputtering ITO film having a base film thickness of less than 50 μm, for example, 25 μm, is applied to the flexible functional element, the flexibility (flexibility) of the base film is too high, and the functional element is being handled. After that, the sputtering ITO layer is easily cracked, and the conductivity of the film may be significantly impaired. Therefore, the present situation is that it has not been put into practical use for flexible functional elements that require high flexibility.

On the other hand, as a manufacturing process of a flexible wiring board, for example, a copper-clad polyimide film obtained by bonding a polyimide film and a copper thin film is subjected to complicated processes such as photoresist layer formation, exposure, etching, and cleaning, according to a desired purpose. A technique for etching a closed circuit is employed.

In order to solve these problems, for example, in the inventions described in Patent Documents 1 to 5, a method of forming a transparent conductive layer on the base film surface using a coating solution for forming a transparent conductive layer is proposed. Specifically, a coating solution for forming a transparent conductive layer mainly composed of conductive oxide fine particles and a resin binder is coated on a base film and dried to form a coating layer, and then compressed (rolled) with a metal roll. After the treatment, the resin binder component was cured to produce a transparent conductive film having a transparent conductive layer. This method has the advantage that the packing density of the conductive fine particles in the transparent conductive layer is increased by rolling with a metal roll, and the electrical (conductive) characteristics and optical characteristics of the film can be greatly increased.

Further, in the inventions described in Patent Documents 6 to 8, a transparent conductive film using a coating liquid for forming a transparent conductive layer as in Patent Documents 1 to 5 and subjected to a compression (rolling) treatment with a metal roll. However, a transparent conductive film with a good handling property was proposed while using an extremely thin base film in which a backing film having a slightly adhesive layer that can be peeled off at the interface with the base film was bonded to the base film side of the transparent conductive film. ing.

On the other hand, in a solar cell, the manufacturing process is to diffuse pn bonds by diffusing reverse-conducting impurities on the light-receiving surface of a monocrystalline or polycrystalline one-conductivity-type silicon substrate. Conventionally, the electrodes formed on each of them have been mainstream. In addition, a solar cell that achieves high output by a back surface field effect by forming an impurity layer containing the same electrode-type impurity portion at a high concentration on a single conductivity type silicon substrate is also common.

Furthermore, a so-called back junction solar cell has been developed in which an electrode is not formed on the light receiving surface of a silicon substrate but a pn junction is formed on the back surface thereof. In back-junction solar cells, there is generally no electrode on the light-receiving surface, so there is no shadow loss due to the electrodes, and a higher output can be obtained compared to solar cells that have electrodes on the light-receiving surface and the back surface of the silicon substrate. Expected.

In the solar cell manufacturing process as described above, when a p + layer region and an n + layer region are formed on one main surface on a support material, a photolithography process is used or a resist ink is used.

As described above, although the plastic mold or surface processing technology is widely used for patterning the electrode of the metal conductive film or the transparent electrode film or the semiconductor layer in the manufacturing process of the semiconductor element or the wiring board of any of the solar cell and the display device, In general patterning methods, there are many pre- and post-processes of resist positive pattern formation, exposure, development etching, resist stripping, post-processing and plastic mold or surface processing with photoresist, etc., resulting in high manufacturing cost. was there.

As a method of forming a transparent electrode layer by patterning to solve these problems, (1) a method of applying a compression (rolling) process to a metal roll or the like after applying a transparent electrode forming coating solution in a predetermined pattern shape in advance (2) A method of patterning by etching or the like after forming a transparent electrode layer that has been compressed (rolled) on the entire surface of the base film is conceivable.

However, in the former method (1), the transparent electrode forming coating liquid is subjected to a compression (rolling) treatment after pattern application, and therefore the pattern transparent electrode is not used when a compression (rolling) treatment facility such as a metal roll is not provided. It is difficult to say that anyone can obtain a transparent electrode layer having an arbitrary pattern easily and at low cost. On the other hand, in the latter method (2), patterning is performed on the transparent electrode film on which the transparent electrode layer subjected to the compression (rolling) treatment is formed on the entire surface. Since this patterning apparatus is widely used at a low price, anyone can obtain a patterned transparent conductive film easily and at a low cost.

Furthermore, regarding the application of the coating solution for forming a transparent electrode to the base film, the method of coating the entire surface of the base film by roll-to-roll is more productive than the method of printing in a predetermined pattern shape, and the patterning is performed. The method of the latter (2) is desirable also from the aspect that it is possible to suppress a decrease in pattern accuracy (pattern position, pattern shape / size accuracy) of the transparent electrode layer due to dimensional deformation of the base film in the manufacturing process. it is conceivable that.

Because of these, when performing highly accurate patterning by a desired printing method on a transparent conductive film with a transparent electrode applied on the entire surface of a base film or a metal-attached film with a metal thin film attached, printing is performed. It is desired to provide a water-soluble paste for plastic molding and surface processing that can easily optimize printing suitability for each printing apparatus even if the printing method is the same or depending on the case.

JP-A-4-237909 JP-A-5-036314 JP 2001-321717 A JP 2002-36411 A JP 2002-42558 A JP 2006-202738 A JP 2006-202739 A WO2007 / 039969

In view of the above-described problems, the present invention has a small number of processing steps in a plastic mold or surface processing step widely used in the manufacturing process of any semiconductor device of a display device or a solar cell, and is simple and excellent in selection accuracy. An object of the present invention is to provide a water-soluble paste that can be used in a plastic mold or surface processing step that can reduce manufacturing costs.

The present inventors have studied to solve the problems in the previous period, and found that the problems in the previous period can be solved by using a water-soluble paste containing a water-soluble polymer or the like, and completed the present invention.

That is, the present invention relates to a plastic or surface processing water-soluble paste composition containing at least one selected from the group consisting of (A) a water-soluble polymer, (B) a surfactant, and (C) inorganic fine particles and organic fine particles. Related to things.

If the water-soluble paste of the present invention is used, a metal conductive thin film formed on a base film by a plating method, a sputtering method, or a bonding method, or conductive oxide fine particles formed by a coating method and a resin binder matrix are used as main components. Water-soluble plastic or surface processing water-soluble plastic containing at least an acid or alkali component, a thickener and a solvent essential for plastic molding or surface processing that deteriorates the metal thin film or the resin binder matrix on the transparent conductive layer Provided is a simple method capable of washing and removing the water-soluble paste together with the transparent conductive layer after applying a paste pattern. Therefore, it is industrially useful because it can be applied to the manufacturing process of transparent electrodes requiring patterns of various flexible functional elements such as liquid crystal display elements, organic electroluminescent elements, electronic paper elements, dispersed electroluminescent elements, solar cells, touch panels, etc. is there.

Further, the water-soluble paste for plastic mold and surface processing is applied to a material to be plastic molded or surface processed by a desired printing method (inkjet printing method, gravure printing method, offset printing method, flexographic printing method, dispenser printing method). The printability at the time of printing by using can be improved.

The water-soluble paste for plastic mold or surface processing of the present invention (hereinafter sometimes simply referred to as water-soluble paste) comprises (A) a water-soluble polymer (hereinafter referred to as component (A)), (B) a surfactant (hereinafter referred to as “water-soluble paste”). , (B) component) and (C) at least one selected from the group consisting of inorganic fine particles and organic fine particles (hereinafter referred to as component (C)).

The component (A) is not particularly limited as long as it is a water-soluble polymer, and known components can be used. The molecular weight of the component (A) is usually preferably 500 to 100,000, particularly preferably 2,000 to 50,000.

As the component (A), either a non-natural product or a natural product can be used. Specific examples of the non-natural substance water-soluble polymer include a polymer having at least one selected from the group consisting of an acidic monomer, (meth) acrylamide and vinyl alcohol as a monomer component. As an acidic monomer, if it has an acidic functional group in a molecule | numerator, it will not specifically limit, A well-known thing can be used. Examples of the acidic functional group include a carboxyl group, a phosphonic acid group, and a sulfonic acid group. Specifically, for example, (meth) acrylic acid, itaconic acid, fumaric acid, (anhydrous) maleic acid, (anhydrous) hymic acid, acetylenedicarboxylic acid, allylmalonic acid, p-hydroxycinnamic acid, (meth) allylsulfone An acid etc. are mentioned. In addition, when introducing a vinyl alcohol unit, it may usually be hydrolyzed after polymerization of vinyl acetate. These monomers may be used alone or in combination of two or more. As long as the component (A) is water-soluble, a monomer that can be copolymerized with these in addition to at least one selected from the group consisting of acidic monomers, (meth) acrylamides, and vinyl alcohols may be used. Examples of the copolymerizable monomer include (meth) acrylic acid esters, styrenes, (meth) acrylonitrile, vinyl chloride and the like. (Meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, ethylhexyl (meth) acrylate, (meth) acrylic acid Examples include cyclohexyl and isobornyl (meth) acrylate. Examples of styrenes include styrene, α-methylstyrene, vinyltoluene and the like.

A commercially available non-natural water-soluble polymer may be used. Specifically, for example, Denka Butyral (manufactured by Denki Kagaku Kogyo Co., Ltd.), ESREC SV, ESREC BK, PVC-HA, PVC-TG (manufactured by Sekisui Chemical Co., Ltd.), SN thickener 601, SN thickener 603, SN thickener 612, SN thickener 613, SN thickener 615, SN thickener 618, SN thickener 621N, SN thickener 630, SN thickener 634, SN thickener 636, SN thickener 4050, SN Dell spars santo 5020, SN del spars santo 5040 ( Sannopco), BYK-420, BYK-425 (Big Chemy), Polystron 117, Polystron 370K, Porostron 372, Polystron 504, Polystron 705, Polystron 1810, Polystro 1401, Policetron 1280, Policetron 1264, Policetron 1228, Arafix 100, Arafix 251S, Arafix 255, Arafix 255LOX, Polymer Jet 902, Polymer Jet 903, Polymer Set 305, Polymer Set 500, Polymer Set 512, Polymer Set HP-710, Polymeron 351T, Polymeron 356-25, Polymeron 385, Polymeron 482S, Polymeron 1308S, Polymeron E-100, Polymeron E-110, Polymeron 360, Polymeron 1383, Polymeron 1329, Tamnori G-36, Tamanori G- 37, Alastor 700, Alastor 703S, Marquide No. 1-No. 8, Marquide 32-30WS, Marquide 3002 (manufactured by Arakawa Chemical Industries, Ltd.) and the like.

Examples of water-soluble polymers derived from natural products include polysaccharides obtained from microorganisms, plants and seaweed, polyamino acids and the like. Examples of the polysaccharide include xanthan gum, alginic acid, cellulose gum, mannan, locust bean gum, guar gum, agarose, hyaluronic acid, curdlan, pectin, gellan gum, gum arabic, tara gum, glucomannan, carrageenan cyclodextrin and the like.

Examples of polyamino acids include polymers of amino acids such as glycine, alanine, leucine, valine, phenylalanine, proline, serine, threonine, lysine, arginine, aspartic acid, and glutamic acid, and may be copolymers of various amino acids. It may be a protein such as gelatin.

Commercially available water-soluble polymers derived from natural products may be used. Specifically, for example, Aphagy Max (manufactured by Ikko Chemical Co., Ltd.), Soagina, Soar Ace, Soar Locust, Tara Gum, Guar Gum, Tamarind Sheet Gum, Psyllium Seed Gum, Soaxane, Hyaluronic Acid (MRC Polysaccharide Co., Ltd.) Aminopiger (Toyobo Co., Ltd.), and the like.

As (B) component used for the water-soluble paste of this invention, if it has surface active ability, it will not specifically limit and a well-known thing can be used. By using the component (B), it is possible to impart further optimum printability according to a desired printing method (inkjet printing method, gravure printing method, offset printing method, flexographic printing method, dispenser printing method). Examples of the component (B) include amphoteric surfactants, anionic surfactants, cationic surfactants, and nonionic surfactants. These may be used alone or in combination of two or more.

The amphoteric surfactant is not particularly limited as long as it is a surfactant having a cationic functional group and an anionic functional group, and known ones can be used. Specifically, alkyl betaine, alkylamine oxide, etc. are mentioned, for example. The anionic surfactant is not particularly limited as long as it is a surfactant having an anionic functional group, and a known one can be used. For example, alkyl sulfate, polyoxyethylene alkyl sulfate, alkyl benzene sulfonate, alkyl naphthalene sulfonate, fatty acid salt, naphthalene sulfonate formalin condensate salt, polycarboxylic acid type polymer surfactant, alkenyl succinate , Alkane sulfonates, polyoxyalkylene alkyl ether phosphates and salts thereof, polyoxyalkylene alkyl ether phosphates and salts thereof, and the like. The cationic surfactant is not particularly limited as long as it is a surfactant having a cationic functional group, and a known one can be used. Examples thereof include alkylamine salts and quaternary ammonium salts. The nonionic surfactant is not particularly limited as long as it is a surfactant without having a cationic functional group and an anionic functional group, and a known one can be used. For example, polyoxyethylene alkyl ether, polyoxyalkylene alkyl ether, polyoxyethylene derivative, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene cured Castor oil, polyoxyethylene alkylamine, polyoxyalkylalkyleneamine, alkylalkanolamide and the like can be mentioned. Although the usage-amount of (B) component is not specifically limited, Usually, it is preferable to use about 0.01-3.0 mass parts of (B) component with respect to 100 mass parts of (A) component, and especially 0.05. Use of ˜2.0 parts by mass is preferable from the viewpoint of printability.

In the water-soluble paste composition of the present invention, the component (C) is essential. Component (C) may be inorganic fine particles or organic fine particles.
Examples of the inorganic fine particles include calcium hydrogen phosphate, magnesium aluminum silicate, calcium silicate, bentonite, silica, magnesium hydroxide, titanium oxide, aluminum hydroxide, calcium carbonate, alumina, tin oxide and the like. When these are used, the average particle size is preferably 10 nm to 50 μm, more preferably 50 nm to 30 μm.

Organic fine particles include rosin, metal salt of rosin, metal salt of aromatic carboxylic acid such as benzoic acid, metal salt of aliphatic carboxylic acid such as stearic acid, acrylic resin that is a polymer of acrylic ester derivative, silicone resin Fluorine resin such as benzoguanamine resin, tetrafluoroethylene resin and polyvinyl fluoride, polyurethane resin, and polystyrene resin are preferably used. Although it does not specifically limit as a metal of a metal salt, Usually, aluminum, calcium, titanium, zirconium, magnesium etc. are mentioned.

  Commercially available fine particles may be used as the organic fine particles. Specific examples include Chemisnow MR, Chemisnow MX, Chemisnow MP, Chemisnow SX (manufactured by Soken Chemical Co., Ltd.). The inorganic fine particles may be commercially available if the average particle size is optimized.

  Although the usage-amount of (C) component is not specifically limited, Usually, it is preferable to use about 0.05-5.0 mass parts of (C) component with respect to 100 mass parts of (A) component, especially 0.1. Use of ˜2.0 parts by mass is preferable from the viewpoint of optimizing printing characteristics.

  In the water-soluble paste of the present invention, the acid component, the inorganic alkali component, and the organic alkali component (hereinafter, the inorganic alkali component and the organic alkali component are sometimes referred to simply as an alkali component depending on the purpose of plastic molding or surface processing. ) Is preferably used. As the acid component, at least one selected from phosphoric acid, hydrogen fluoride, ammonium fluoride, and ammonium hydrogen fluoride can be used. Examples of the inorganic alkali component include potassium hydroxide, sodium hydroxide, tetramethylammonium hydroxide, lithium hydroxide, rubidium hydroxide, cesium hydroxide, ammonia and the like. Examples of the organic alkali component include amines such as ethanolamine and ethylenediamine, and tetraalkylammonium hydroxys such as tetraethylammonium hydroxide and tetramethylammonium hydroxide. These may be used alone or in combination. The compounding amount of the acid or alkali component varies depending on the type of material to be molded or surface processed, but is preferably 1 to 40% by mass, preferably 5 to 30% by mass.

The water-soluble paste of the present invention usually contains water. Although content of water is not specifically limited, Usually, about 10-95 mass parts with respect to 100 mass parts of (A) component, Preferably it is 30-90 mass parts.

When applying the water-soluble paste of the present invention to a pattern using any one of the screen printing method, the ink jet printing method, the gravure printing method, the offset printing method, the flexographic printing method, and the dispenser printing method, an organic solvent is optionally added. Can be used. Examples of the organic solvent to be used include alcohols such as isopropyl alcohol, diethylene glycol, glycerin and propylene glycol, and amide solvents such as polyvinylpyrrolidone and dimethylformamide.

In addition, when there is an effect on storage stability, such as thickening by using an acid component or an alkali component, a precursor paste consisting only of an acid or alkali component and a precursor paste consisting of other components are prepared and used. It can be solved by using a two-component mixed system that is used immediately before mixing. These precursor pastes may use an organic solvent in an amount that does not impair the printability of the water-soluble paste of the present invention.

The water-soluble paste of the present invention is prepared by mixing each component and applying a treatment (homogenization treatment) for uniform dissolution, followed by a purification treatment by filtration as necessary. By performing purification by filtration, the fineness when pattern printing can be improved. As a homogenization treatment method, a general-purpose method such as ultrasonic treatment, a homogenizer, a three-roll mill, or a planetary mill can be applied.

The pattern application of the water-soluble paste of the present invention is selected from the above-mentioned printing methods that can achieve a desired printing accuracy, but screen printing is performed in view of optimizing printability such as viscosity, thixotropy, and rheological properties of the water-soluble paste. Is preferred. In the case of screen printing, the viscosity of the water-soluble paste is 300 to 90000 mPa · s, preferably 1500 to 40000 mPa · s. It is preferable to prepare so that it may become s. If the viscosity is 300 mPa · s or less, the fluidity of the water-soluble paste for plastic molding and surface processing becomes high, and the accuracy of the printing pattern itself decreases. If the viscosity is 100000 mPa · s or more, the viscosity is too high, making it difficult to filter and homogenize the water-soluble paste for plastic molding and surface processing, and to deteriorate printability.

Examples of the present invention will be specifically described below, but the present invention is not limited to these examples.

Example 1
While mixing 200 g of distilled water, 209 g of N-methylpyrrolidone and 1.1 g of propylene glycol and stirring sufficiently, 437 g of 85% phosphoric acid, 10 g of Chemis Snow MP (manufactured by Soken Chemical Co., Ltd.), BYK (Big Chemie Co., Ltd.) 0.9 g) was added. After stirring for 1 hour, the viscosity was adjusted to 1050 mPa · s while adding Denkabutyral (# 3000-1) to obtain a water-soluble paste. When this water-soluble paste was printed on a wafer surface using a 280 mesh stainless steel woven screen, it exhibited excellent printability.

Example 2
20 g of potassium hydroxide was dissolved in 150 g of distilled water (solution A). Separately, 1 g of Arafix 100 (Arakawa Chemical Industries, Ltd.), a water-soluble polymer, and 0.2 g of gellan gum were dissolved in 100 g of distilled water, and then 3 g of Chemisnow MP (manufactured by Soken Chemical Co., Ltd.) was dissolved. The mixture was further stirred for 1 hour (Liquid B). Next, all of the liquid A and the liquid B were mixed, and the viscosity was adjusted to 980 mPa · s while adding distilled water to obtain a water-soluble paste. Thereafter, when the same operation as in Example 1 was performed, excellent printability was exhibited.

Claims (5)

(A) Water-soluble polymer, (B) Surfactant and (C) Water-soluble paste composition for plastic mold or surface processing containing at least one selected from the group consisting of inorganic fine particles and organic fine particles. The plastic according to claim 1, wherein the water-soluble polymer (A) is a polymer, a polysaccharide or a polyamino acid containing at least one selected from the group consisting of an acidic monomer, (meth) acrylamide and vinyl alcohol as a monomer component. Water-soluble paste composition for mold or surface processing. (B) The water-soluble paste for plastic molding or surface processing according to claim 1 or 2, wherein the surfactant is an amphoteric surfactant, an anionic surfactant, a cationic surfactant or a nonionic surfactant. Composition. The inorganic fine particles are at least one selected from the group consisting of calcium hydrogen phosphate, magnesium aluminum silicate, calcium silicate, bentonite, silica, magnesium hydroxide, titanium oxide, aluminum hydroxide, calcium carbonate, alumina, and tin oxide. The water-soluble paste composition for plastic mold or surface processing according to any one of claims 1 to 3. Organic fine particles are composed of rosin acid, metal salt of rosin acid, metal salt of aromatic carboxylic acid, metal salt of aliphatic carboxylic acid, acrylic resin, silicone resin, benzoguanamine resin, fluorine resin, urethane resin and polystyrene resin. The water-soluble paste composition for plastic mold or surface processing according to claim 1, which is at least one selected.