Anti-plating composition and its dry film

Abstract

Provided are an anti-electroplating composition and a dry film thereof that have excellent anti-electroplating properties even without an epoxy resin and excellent stripping properties. The anti-electroplating composition contains (A) a polyfunctional acrylic resin, (B) talc, and (C) an inorganic filler other than talc, and does not contain an epoxy resin. Among them, relative to 100 parts by mass of the solid content of the (A) polyfunctional acrylic resin, the (B) talc is 4 to 50 parts by mass, and the (C) inorganic filler other than talc is 5 to 55 parts by mass.

Description

Technical Field

[0001] The present invention relates to an anti - plating composition, specifically to an anti - plating composition used in manufacturing the electrodes of solar cells and its dry film, belonging to the field of anti - plating materials for solar cell manufacturing. Background Art

[0002] Globally, energy and environmental issues have been attracting increasing attention, and the utilization of new energy such as solar energy is being actively promoted. A solar cell is a device that directly converts light energy into electrical energy through the photovoltaic effect or the photochemical effect. Currently, crystalline silicon solar cells operating based on the photovoltaic effect are the mainstream and have been applied in many fields such as transportation, communication, meteorology, satellites, lighting, and power stations.

[0003] Regarding the solar cell electrodes, which are the core components of solar cells, and their manufacturing methods, various studies and developments have been actively carried out so far. For example, Patent Document 1 discloses a method for printing photovoltaic electrodes of different shapes, including the following steps: Step 1, spin - coat a layer of photoresist on the surface of the cell wafer; Step 2, place it in an ultraviolet exposure machine equipped with a specific - pattern photomask and irradiate with ultraviolet light; Step 3, place it in a developer for development to expose the cell wafer substrate, obtaining a patterned cell wafer; Step 4, spin - coat a layer of solar paste on the surface of the patterned cell wafer; Step 5, soak it in an organic solvent to remove the photoresist; Step 6, perform sintering to obtain photovoltaic electrodes of different shapes.

[0004] In order to further reduce the cost and increase the efficiency of solar cells, the use of electroplating to fabricate the metal electrodes of solar cells has also attracted much attention. This method mainly uses metals such as copper and nickel, which have lower costs, to partially or completely replace expensive silver. When using electroplating to fabricate electrodes, it is necessary to define the position and size of the metal electrodes on the surface of the solar cell through a patterned mask, and a photoresist (also known as anti - plating ink) is used for the mask opening process. For example, Patent Document 2 discloses a method for fabricating a photovoltaic cell electrode, including the following steps: depositing a mask material on the side and at least one surface of the photovoltaic device; patterning the mask material located on the surface to form local openings of the mask material; treating the mask material on the side to make it corrosion - resistant and anti - plating; electrochemically depositing a metal electrode in the openings of the mask material on the surface of the device; removing the mask material on the surface and side of the device. This mask material can be used in the mask opening process in the form of a dry film. However, the processes of laminating, pressing, and peeling the dry film are likely to cause the silicon wafer to break, and moreover, the stripping ability of the dry film is poor, which is not conducive to the large - scale mass production of solar cell wafers.

[0005] In addition, the mask material can also be used in the form of a liquid for the mask opening process. For example, Patent Document 3 discloses a method for manufacturing a photovoltaic cell electrode, including the following steps: depositing a liquid mask material containing a photosensitive component onto the surface of a photovoltaic device whose surface is a dielectric layer, a transparent conductive oxide, or a conductive seed layer; exposing a partial area of the mask material to laser light; developing to remove the mask material in the unexposed area from the surface of the photovoltaic device, so that the dielectric layer, the transparent conductive oxide, or the conductive seed layer is exposed, thereby forming a local opening of the mask material; etching the dielectric layer to expose the semiconductor layer at the opening position, and then attaching a conductive material to the semiconductor surface at the opening position by means of electrochemical deposition; or attaching a conductive material to the surface of the photovoltaic device at the local opening by means of electrochemical deposition on the transparent conductive oxide or the conductive seed layer at the opening; removing the mask material on the surface. However, so far, when a photoresist is used as the mask material for manufacturing the electrodes of a solar cell, a satisfactory stripping property cannot be obtained.

[0006] Prior art documents

[0007] Patent documents

[0008] Patent Document 1: CN105762203A

[0009] Patent Document 2: CN113013295A

[0010] Patent Document 3: CN112993087A Summary of the invention

[0011] Problems to be solved by the invention

[0012] As described above, the photoresist used in the past for manufacturing the electrodes of a solar cell has the problem of poor stripping property.

[0013] The inventors of the present invention have found through research that the reason for the above problem is that conventional photoresists or dry films usually contain epoxy resins, and the epoxy resins sometimes act as adhesives, resulting in the difficulty of stripping and removing the anti-electroplating mask formed by curing the photoresist or dry film. On the other hand, the inventors of the present invention have also found that if the epoxy resin is removed from the conventional photoresist in order to improve the stripping property, the problem of poor anti-electroplating performance occurs.

[0014] Therefore, there is an urgent need to develop a photoresist that has excellent stripping property (i.e., is easily stripped and removed) while satisfying the anti-electroplating performance.

[0015] In view of the above situation, the object of the present invention is to provide an anti-electroplating composition and its dry film that have excellent anti-electroplating performance even without containing epoxy resins and have excellent stripping property.

[0016] Solutions for solving the problems

[0017] The inventors of the present invention conducted in - depth research and found that by simultaneously including talc and an inorganic filler other than talc in an anti - electroplating composition containing a polyfunctional acrylic resin and not containing an epoxy resin, and making the contents of talc and the inorganic filler other than talc within a specific range, the anti - electroplating composition can fully meet requirements such as anti - electroplating performance and stripping properties, thereby completing the present invention.

[0018] That is, the present invention is as described below.

[0019] 1. An anti - electroplating composition, characterized in that it contains (A) a polyfunctional acrylic resin, (B) talc, (C) an inorganic filler other than talc, and does not contain an epoxy resin, wherein, relative to 100 parts by mass of the solid content of the (A) polyfunctional acrylic resin, the (B) talc is 4 - 50 parts by mass, and the (C) inorganic filler other than talc is 5 - 55 parts by mass.

[0020] 2. The anti - electroplating composition according to 1, characterized in that the (A) polyfunctional acrylic resin has, in addition to a plurality of (meth)acryloyl groups, a plurality of carboxyl groups in the molecule.

[0021] 3. The anti - electroplating composition according to 1 or 2, characterized in that the (A) polyfunctional acrylic resin contains an epoxy - modified acrylic resin.

[0022] The epoxy - modified acrylic resin is: a resin obtained by reacting a polyfunctional epoxy resin with (meth)acrylic acid and adding a dibasic anhydride to the hydroxyl group present in the side chain; or a resin obtained by further adding a compound having one epoxy group and one or more (meth)acryloyl groups to this resin.

[0023] 4. The anti - electroplating composition according to 3, characterized in that the epoxy - modified acrylic resin is: a resin obtained by reacting a phenol novolac type epoxy resin or a cresol novolac type epoxy resin with (meth)acrylic acid and adding tetrahydrophthalic anhydride to the hydroxyl group present in the side chain; or a resin obtained by further adding glycidyl (meth)acrylate to this resin.

[0024] 5. The anti - electroplating composition according to 1 or 2, characterized in that the average particle size (D50) of the (B) talc is 1.0 - 20.0 μm.

[0025] 6. The anti - electroplating composition according to 1 or 2, characterized in that the (C) inorganic filler other than talc is a spherical powder.

[0026] 7. The anti - electroplating composition according to 1 or 2, wherein the inorganic filler other than talc in (C) comprises at least any one selected from silica, barium sulfate, and calcium carbonate.

[0027] 8. The anti - electroplating composition according to 7, wherein the inorganic filler other than talc in (C) comprises silica.

[0028] 9. The anti - electroplating composition according to 8, wherein the average particle size (D50) of the silica is 0.1 - 10.0 μm.

[0029] 10. Use of the anti - electroplating composition according to any one of 1 - 9 in manufacturing an electrode of a solar cell.

[0030] 11. A dry film, characterized in that it is obtained by coating the anti - electroplating composition according to any one of 1 - 9 above on a carrier film and drying.

[0031] Advantages of the Invention

[0032] According to the present invention, it is possible to provide an anti - electroplating composition and its dry film that have excellent anti - electroplating performance even without an epoxy resin and excellent stripping properties. Detailed Embodiments

[0033] Various exemplary embodiments, features, and aspects of the present invention will be described in detail below. The word "exemplary" used here means "serving as an example, an embodiment, or illustrative". Any embodiment described as "exemplary" here does not have to be construed as superior to or better than other embodiments.

[0034] In addition, for better illustration of the present invention, numerous specific details are given in the following detailed embodiments. Those skilled in the art should understand that the present invention can also be implemented without some specific details. In other instances, methods, means, equipment, and steps well - known to those skilled in the art are not described in detail so as to highlight the gist of the present invention.

[0035] Unless otherwise stated, the units used in this specification are all international standard units, and the numerical values and numerical ranges appearing in the present invention should be understood to include the inevitable systematic errors in industrial production.

[0036] In this specification, the meaning expressed by "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

[0037] In this specification, the terms "some specific / preferred embodiments", "other specific / preferred embodiments", "embodiments", etc. refer to the specific elements related to the embodiments (e.g., features, structures, properties, and / or characteristics) described herein, which are included in at least one of the embodiments described herein, and may or may not be present in other embodiments. Additionally, it should be understood that the elements may be combined in various embodiments in any suitable manner.

[0038] In this specification, the numerical range represented by "numerical value A to numerical value B" refers to a range that includes the endpoint numerical values A and B.

[0039] In this specification, (meth)acrylic acid refers to a term that collectively refers to acrylic acid, methacrylic acid, and their mixtures, and the same applies to other similar expressions.

[0040] The present invention relates to an anti-electroplating composition, which is characterized by comprising (A) a polyfunctional acrylic resin, (B) talc, and (C) an inorganic filler other than talc, and does not contain an epoxy resin. Among them, relative to 100 parts by mass of the solid content of the (A) polyfunctional acrylic resin, the (B) talc is 4 to 50 parts by mass, and the (C) inorganic filler other than talc is 5 to 55 parts by mass.

[0041] The following provides a detailed description of each component of the anti-electroplating composition of the present invention.

[0042] (A) Multifunctional acrylic resin

[0043] The (A) polyfunctional acrylic resin contained in the anti-electroplating composition of the present invention refers to a resin having multiple (meth)acryloyl groups in the molecule, which is a component that polymerizes and / or crosslinks and cures by means of the ethylenically unsaturated double bonds possessed by the (meth)acryloyl groups upon light irradiation.

[0044] As the (A) polyfunctional acrylic resin, there is no particular limitation. For example, it can be a resin having multiple (meth)acryloyl groups in the molecule obtained by acrylic modification of an epoxy resin, a phenolic resin, a polycarbonate resin, a polyether resin, a polyester resin, a polyolefin resin, or a polyurethane resin.

[0045] In addition, from the viewpoint of imparting alkali developability, it is preferable that in addition to having a plurality of (meth)acryloyl groups, the molecule also has a plurality of carboxyl groups. From the viewpoint of further improving the electroplating resistance and stripping properties, the double bond equivalent of the (A) polyfunctional acrylic resin is preferably 220 to 410 g / eq, more preferably 250 to 390 g / eq, and further preferably 270 to 320 g / eq. From the viewpoints of alkali developability and resolution, the acid value of the (A) polyfunctional acrylic resin is preferably 5 to 100 mgKOH / g, more preferably 10 to 90 mgKOH / g, and further preferably 20 to 80 mgKOH / g.

[0046] From the viewpoint of exhibiting the effects of the present invention such as excellent electroplating resistance and stripping properties even without an epoxy resin, an epoxy-modified acrylic resin is preferred. As the epoxy-modified acrylic resin, typically, a resin obtained by reacting a polyfunctional epoxy resin with (meth)acrylic acid and adding a dicarboxylic anhydride to the hydroxyl group present in the side chain; and a resin obtained by further adding a compound having one epoxy group and one or more (meth)acryloyl groups in the molecule to the resin. Examples of the compound having one epoxy group and one or more (meth)acryloyl groups herein include glycidyl (meth)acrylate, α-methylglycidyl (meth)acrylate, and 3,4-epoxycyclohexylmethyl methacrylate.

[0047] As the polyfunctional epoxy resin used for synthesizing the epoxy-modified acrylic resin, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol novolac type epoxy resin, biphenyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, dicyclopentadiene novolac type epoxy resin, triphenylmethane type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phosphorus-containing epoxy resin, anthracene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin, fluorene type epoxy resin, aminophenol type epoxy resin, aminocresol type epoxy resin, alkylphenol type epoxy resin, etc. These epoxy resins can be used alone or in combination of two or more as appropriate. Among these polyfunctional epoxy resins, from the viewpoint of further exhibiting the effects of the present invention, phenol novolac type epoxy resin and cresol novolac type epoxy resin are preferred, and phenol novolac type epoxy resin is more preferred.

[0048] Examples of the dicarboxylic anhydride used for synthesizing the epoxy-modified acrylic resin include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. These epoxy resins can be used alone or in combination of two or more as appropriate. From the viewpoint of further exhibiting the effects of the present invention, tetrahydrophthalic anhydride is preferred.

[0049] Therefore, from the viewpoint of further exerting the effects of the present invention, it is further preferred to react a phenol novolac type epoxy resin or a cresol novolac type epoxy resin with (meth)acrylic acid, and add tetrahydrophthalic anhydride to the hydroxyl group present in the side chain to form an epoxy-modified acrylic resin; particularly preferred is an epoxy-modified acrylic resin obtained by reacting a phenol novolac type epoxy resin with acrylic acid and adding tetrahydrophthalic anhydride to the hydroxyl group present in the side chain. From the same viewpoint, an epoxy-modified acrylic resin obtained by further adding glycidyl (meth)acrylate to these epoxy-modified acrylic resins is also preferred.

[0050] As the above-mentioned (A) polyfunctional acrylic resin, commercially available products or synthetic products can be used. As commercially available products, for example, the GF series manufactured by Guangzhou Starry Electronic Raw Materials Co., Ltd., such as GF-105, GF-159, GF-148, etc. can be cited. Specific examples of synthetic products can be the compounds listed below:

[0051] (1) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin with (meth)acrylic acid and adding a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, or hexahydrophthalic anhydride to the hydroxyl group present in the side chain.

[0052] (2) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl group of a bifunctional epoxy resin with epichlorohydrin with (meth)acrylic acid and adding a dibasic acid anhydride to the generated hydroxyl group.

[0053] (3) A reaction product is obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide, the reaction product is reacted with a monocarboxylic acid containing an unsaturated group, and the reaction product thus obtained is reacted with a polybasic acid anhydride to obtain a carboxyl group-containing resin.

[0054] (4) A reaction product is obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate, the reaction product is reacted with a monocarboxylic acid containing an unsaturated group, and the reaction product thus obtained is reacted with a polybasic acid anhydride to obtain a carboxyl group-containing resin.

[0055] (5) A carboxyl group-containing resin obtained by further adding a compound having one epoxy group and one or more (meth)acryloyl groups in the molecule, such as glycidyl (meth)acrylate, α-methylglycidyl (meth)acrylate, or 3,4-epoxycyclohexylmethyl methacrylate, to the carboxyl group-containing resin described in the above (1) to (4).

[0056] (A) The weight-average molecular weight of the polyfunctional acrylic resin is generally preferably 2,000 to 150,000, more preferably 3,000 to 30,000, and still more preferably 4,000 to 15,000. When the weight-average molecular weight is 2,000 or more, the resolution is good. On the other hand, when the weight-average molecular weight is 150,000 or less, the developability is good.

[0057] Relative to the total mass of the anti-electroplating composition, the compounding amount of (A) the polyfunctional acrylic resin is preferably 10 to 95% by mass, more preferably 20 to 80% by mass, and still more preferably 30 to 75% by mass. When in the above compounding amount range, the viscosity of the anti-electroplating composition is appropriate, the coatability and the like can be improved, it is suitable for processes such as screen printing, spraying, and curtain coating, and the anti-electroplating performance is good.

[0058] (B) Talc

[0059] As the talc contained in the anti-electroplating composition of the present invention, the mother rock may be any one of magnesium carbonate, serpentine, silica / silica-alumina, and magnesium deposits, and may be a so-called silicate mineral. The shape may be massive, may be micropowdery, or may be flaky. Surface treatment may or may not be performed. The average particle size (D50) of the talc is suitably 1.0 to 20.0 μm, more preferably 2.0 to 10 μm, and still more preferably 2.5 to 8.0 μm. Examples of commercially available products include HD25 manufactured by Pingdu Talc Mining Co., Ltd. in Shandong Province, and LMP-100 manufactured by Fuji Talc Industry Co., Ltd.

[0060] It should be noted that the above average particle size refers to the value of the cumulative average particle size 50% (D50) when making a particle size distribution based on volume, and is the D50 value measured by the laser diffraction method, and can be obtained by a laser diffraction type particle size distribution measuring device and a measuring device based on the dynamic light scattering method. As the measuring device based on the laser diffraction method, Microtrac MT3300EXII manufactured by MicrotracBEL Co., Ltd. can be cited, and as the measuring device based on the dynamic light scattering method, Nanotrac Wave II UT151 manufactured by MicrotracBEL Co., Ltd. can be cited.

[0061] Relative to 100 parts by mass of the solid content mass of (A) the polyfunctional acrylic resin, the (B) talc is 4 to 50 parts by mass. When within the above range, when used in combination with (C) an inorganic filler other than talc, excellent anti-electroplating performance can be ensured while improving the stripping property. From the viewpoint of further exerting the effects of the present invention, it is preferably 4.5 to 45 parts by weight, more preferably 6 to 40 parts by weight.

[0062] (C) Inorganic filler other than talc

[0063] The present invention contains (B) talc and also contains (C) an inorganic filler other than talc. Through the combination of (B) talc and (C) an inorganic filler other than talc, excellent anti-electroplating performance is ensured while improving the stripping property.

[0064] Examples of the (C) inorganic filler other than talc include titanium oxide, silica, barium sulfate, barium titanate, Neusilicate, clay, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, silicon nitride, aluminum nitride, etc. The shape of the (C) inorganic filler other than talc can include spherical, needle-like, flaky, scaly, hollow, irregular, hexagonal, cubic, lamellar, etc. From the viewpoint of high filling of the inorganic filler, the (C) inorganic filler other than talc is preferably spherical powder.

[0065] With respect to 100 parts by mass of the solid content of the (A) polyfunctional acrylic resin, the (C) inorganic filler other than talc is 5 to 55 parts by mass. If it is within the above range, when used in combination with (B) talc, excellent anti-electroplating performance can be ensured while improving the stripping property. From the viewpoint of further exerting the effects of the present invention, it is preferably 8 to 43 parts by weight, more preferably 10 to 35 parts by weight.

[0066] From the viewpoint of using in combination with talc to further improve the anti-electroplating property, silica, barium sulfate, and calcium carbonate are preferred, and silica is more preferred. As silica, it can be either amorphous or crystalline, or a mixture of them. Amorphous (fused) silica is particularly preferred. Surface treatment can be carried out or not. The average particle size (D50) of silica is suitably 0.1 to 10.0 μm, more preferably 1.0 to 8.0 μm, and further preferably 2.0 to 6.0 μm. Examples of commercially available products of silica include CS1002 and CS1002A manufactured by Jiangsu Lianrui New Materials Co., Ltd., A-8 manufactured by Sibelco Co., Ltd., SE-40 manufactured by Tokuyama Co., Ltd., MSV25G manufactured by Ryosen, MLV-2114 manufactured by Ryosen, SO-E5 manufactured by ADMATECHS, SO-E2 manufactured by ADMATECHS, etc.

[0067] Epoxy resin free

[0068] The present invention improves the stripping property by not containing epoxy resin. Epoxy resin refers to a resin having an epoxy group, including polyfunctional epoxy resins having two or more epoxy groups. The epoxy resin can be liquid, solid or semi-solid. Examples of the polyfunctional epoxy resin include bisphenol A type epoxy resin; brominated epoxy resin; novolac type epoxy resin; bisphenol F type epoxy resin; hydrogenated bisphenol A type epoxy resin; glycidylamine type epoxy resin; hydantoin type epoxy resin; alicyclic epoxy resin; trihydroxyphenylmethane type epoxy resin; xylenol type or biphenol type epoxy resin or a mixture thereof; bisphenol S type epoxy resin; bisphenol A novolac type epoxy resin; tetrahydroxyphenylethane type epoxy resin; heterocyclic epoxy resin; tris(glycidyl) isocyanurate (TGIC); diglycidyl phthalate resin; tetraglycidyl xylylenediamide resin; naphthalene group-containing epoxy resin; dicyclopentadiene type epoxy resin; glycidyl methacrylate copolymer type epoxy resin; copolymer epoxy resin of cyclohexyl maleimide and glycidyl methacrylate; epoxy-modified polybutadiene rubber derivative; CTBN-modified epoxy resin, etc.

[0069] It should be noted that the epoxy resin not contained in the present application does not include: resins modified to no longer have an epoxy group; compounds or mixtures having a partial structure derived from an epoxy group in the molecule but not having an epoxy group; and compounds or mixtures using an epoxide in the synthesis but not having an epoxy group in the molecule.

[0070] Other components

[0071] In addition to containing the above-mentioned (A) polyfunctional acrylic resin, (B) talc, and (C) inorganic filler other than talc, the electroplating-resistant composition of the present invention may further contain other components. It should be noted that the other components do not include substances belonging to epoxy resin.

[0072] The electroplating-resistant composition of the present invention may further be compounded with a (D) polymerizable monomer having two or more ethylenically unsaturated groups in the molecule. The (D) polymerizable monomer is photocured or crosslinked by irradiation with active energy rays, making the electroplating-resistant composition of the present invention insoluble in an aqueous alkali solution, or contributing to the resin composition of the present invention being insoluble in an aqueous alkali solution.

[0073] As such (D) polymerizable monomers, for example, conventionally well-known polyester (meth)acrylates, polyether (meth)acrylates, carbonate (meth)acrylates, urethane (meth)acrylates can be used. Specifically, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate can be cited; diacrylates of diols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol, and propylene glycol; acrylamides such as N,N-dimethylacrylamide, N-hydroxymethylacrylamide, and N,N-dimethylaminopropylacrylamide; aminoalkyl acrylates such as N,N-dimethylaminoethyl acrylate and N,N-dimethylaminopropyl acrylate; polyacrylates of polyols such as hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, and trihydroxyethyl isocyanurate or their ethylene oxide adducts, propylene oxide adducts, or ε-caprolactone adducts; polyacrylates such as phenoxyacrylate, bisphenol A diacrylate, and ethylene oxide adducts or propylene oxide adducts of these phenols; polyacrylates of glycidyl ethers such as glycerol diglycidyl ether, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, and triglycidyl isocyanurate; not limited to the above, acrylate esters obtained by directly acryloylating polyols such as polyether polyols, polycarbonate diols, hydroxyl-terminated polybutadiene, and polyester polyols, or urethane acrylation using diisocyanates, melamine acrylate, and at least any one of various methacrylate esters corresponding to the above acrylate esters, etc. can be cited.

[0074] These (D) polymerizable monomers can be used alone or in the form of a mixture of two or more.

[0075] From the viewpoint of improving resolution and anti-plating properties, the (D) polymerizable monomer preferably has two or more ethylenically unsaturated groups derived from (meth)acrylic groups in the molecule, more preferably has three or more ethylenically unsaturated groups derived from (meth)acrylic groups in the molecule, and further preferably has four or more ethylenically unsaturated groups derived from (meth)acrylic groups in the molecule.

[0076] The molecular weight of the (D) polymerizable monomer is usually preferably 200 to 3000, more preferably 250 to 2000, and further preferably 300 to 1000. When the weight-average molecular weight is 200 or more, the resolution is good. On the other hand, when the weight-average molecular weight is 3000 or less, the developability is good.

[0077] With respect to 100 parts by mass of the solid content of the (A) polyfunctional acrylic resin, it is appropriate that the compounding amount of the (D) polymerizable monomer is in the range of 5 to 40 parts by mass. When the compounding amount of the photopolymerizable monomer is 5 parts by mass or more, the effect of imparting photocurability becomes good. On the other hand, when it is 40 parts by mass or less, the electroless plating resistance property becomes good. More preferably, it is 8 to 35 parts by mass, and further preferably 10 to 30 parts by mass.

[0078] In addition, the electroless plating resistance composition of the present invention may further contain (E) polyamine. The polyamine refers to a compound having multiple amino groups in the molecule. As the amino group contained in the (E) polyamine, any one or two or more of primary amino group, secondary amino group, tertiary amino group, and quaternary ammonium group can be used. From the viewpoint of improving the electroless plating resistance property, it is preferably included a primary amino group. By containing the (E) polyamine, the curability of the electroless plating resistance composition is improved, thereby improving the electroless plating resistance property.

[0079] Examples of the (E) polyamine include ethylenediamine, hexamethylenediamine, dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine, guanamine, methylguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-s-triazine, 2-vinyl-2,4-diamino-s-triazine, 2-vinyl-4,6-diamino-s-triazine-isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-s-triazine-isocyanuric acid adduct, hexamethylenetetramine, etc. These (C) polyamines can be used alone or in the form of a mixture of two or more.

[0080] Among these (E) polyamines, from the viewpoint of improving the electroless plating resistance property, polyamines having a triazine structure in the molecule are more preferred, and melamine is particularly preferred.

[0081] The compounding amount of the (E) polyamine is not particularly limited, and it can be 0.5 to 10.0 parts by mass with respect to 100 parts by mass of the solid content of the (A) polyfunctional acrylic resin. From the viewpoint of suitably exerting the effects of the present invention, it is preferably 1.5 to 8.0 parts by mass, and further preferably 2.5 to 5.0 parts by mass.

[0082] In addition, the electroless plating resistance composition of the present invention may further contain (F) a photopolymerization initiator. As the (F) photopolymerization initiator, any photopolymerization initiator commonly used in electroless plating resistance compositions can be used, and there is no particular limitation.

[0083] As the (F) photoinitiator, examples thereof include acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyl diphenylphosphine oxide, hydroxyketone compounds such as 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexyl phenyl ketone, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methylpropanone, 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropanoyl)benzyl)phenyl)-2-methylpropan-1-one, aromatic ketones such as benzophenone, N,N'-tetraalkyl-4,4'-diaminobenzophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 4,4'-bis(dimethylamino)benzophenone (Michler's ketone), 4,4'-bis(diethylamino)benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1-morpholinobenzone)-butan-1-one, 2-ethylanthraquinone, phenanthraquinone and other aromatic ketones, benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, benzoins such as methyl benzoin, ethyl benzoin, benzoyl derivatives such as benzoyl dimethyl ketal, 2,4,5-triaryl imidazole dimers such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2,4-bis(p-methoxyphenyl)-5-phenylimidazole dimer, 2-(2,4-dimethoxyphenyl)-4,5-diphenylimidazole dimer, acridine derivatives such as 9-phenylacridine, 1,7-bis(9,9'-acridinyl)heptane, N-phenylglycine, N-phenylglycine derivatives, coumarin compounds, and the like.

[0084] As commercially available (F) photoinitiators, examples thereof include Omnirad TPO, Omnirad127, Omnirad184, Omnirad1173, Omnirad2959, Omnirad907, Omnirad MBF, EAB, etc. manufactured by IGM RESINS B.V.

[0085] Such (F) photoinitiators can be used alone or in the form of a mixture of two or more.

[0086] In addition, the anti-plating composition of the present invention may further contain (G) a colorant. As the (E) colorant, known and commonly used colorants can be used, such as perylene-based, phthalocyanine-based, anthraquinone-based, monoazo-based, bisazo-based, azo lake-based, benzimidazolone-based, perylene-based, diketopyrrolopyrrole-based, condensed azo-based, anthraquinone-based, quinacridone-based, isoindolinone-based, anthraquinone-based, etc. Such (G) colorants can be used alone or in the form of a mixture of two or more.

[0087] Furthermore, the anti-plating composition of the present invention may also contain (H) an organic solvent, which is used for the preparation and viscosity adjustment of the composition.

[0088] Examples of the (H) organic solvent include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, etc. More specifically, there are ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, diethylene glycol ethyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, and propylene glycol butyl ether acetate; alcohols such as ethanol, propanol, ethylene glycol, and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, naphtha, hydrogenated naphtha, and solvent naphtha. Such (H) organic solvents can be used alone or in the form of a mixture of two or more.

[0089] In addition, the anti-plating composition of the present invention may also be compounded with known and commonly used additives such as defoamers and / or leveling agents of silicone-based, fluorine-based, polymer-based, etc., silane coupling agents of imidazole-based, thiazole-based, triazole-based, etc., antioxidants, thickeners, sensitizers, etc. as needed.

[0090] The anti-plating composition of the present invention can also be made into the form of a dry film, and the dry film has a carrier film (support) and a layer formed of the above anti-plating composition on the carrier film.

[0091] When forming the dry film, the anti-plating composition of the present invention is diluted with the aforementioned organic solvent and adjusted to an appropriate viscosity, and then coated on the carrier film with a uniform thickness using a bevel wheel coater, doctor blade coater, lip coater, bar coater, extrusion coater, reverse coater, transfer roll coater, gravure coater, spray coater, etc. Usually, it is dried at a temperature of 50 to 130 °C for 1 to 30 minutes to form a resin layer as a dry coating film. There is no particular limitation on the resin layer, and it is usually preferably selected in the range of 10 to 150 μm, more preferably 20 to 60 μm, based on the dry film thickness.

[0092] As the carrier film, a plastic film is used, and preferably a polyester film such as polyethylene terephthalate, a polyimide film, a polyamideimide film, a polypropylene film, a polystyrene film or the like is used. There is no particular limitation on the thickness of the carrier film, and it is generally suitably selected within the range of 10 to 150 μm.

[0093] At this time, after the resin layer is formed on the carrier film, for the purpose of preventing dust from adhering to the surface of the resin layer or the like, it is preferable to further laminate a peelable covering film on the surface of the resin layer. As the peelable covering film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper or the like can be used. When the covering film is peeled off, the adhesive force between the resin layer and the covering film is less than the adhesive force between the resin layer and the carrier film.

[0094] As a method for manufacturing a solar cell electrode using the anti-electroplating composition or the dry film of the present invention, a known manufacturing method can be adopted.

[0095] For example, the anti-electroplating composition of the present invention can be adjusted to a viscosity suitable for the coating method as needed, and it is coated on the surface of a solar cell wafer formed into a pyramidal texture by methods such as screen printing, curtain coating, spraying, roll coating or the like. As needed, the solvent contained in the composition is volatilized and dried at a temperature of, for example, 60 to 100 °C to form a coating film. Or the dry film of the present invention is laminated on the surface of a solar cell wafer formed into a pyramidal texture, and the carrier film is peeled off, so as to form a layer formed by the anti-electroplating composition on the surface of the solar cell wafer. Then, selective exposure is performed by irradiating active energy rays through a photomask having a specified exposure pattern, and the unexposed portion is developed with a developer such as a 1 to 2% Na2CO3 or K2CO3 solution at a temperature of about 30 °C for, for example, 60 to 90 seconds to form an anti-electroplating mask having a specified exposure pattern. Electroplating is performed on the surface of the wafer having the anti-electroplating mask, so as to form a metal layer as an electrode on the surface of the wafer at the pattern notch. Then, the anti-electroplating mask is removed by washing with a NaOH or KOH solution at a temperature of, for example, 40 to 70 °C, and then a welding layer is deposited by PVD. After sintering, a solar cell wafer assembly having an electrode is obtained.

[0096] Examples

[0097] The embodiments of the present invention will be described in detail below in conjunction with the examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention. For those not specified in the examples, they are carried out under conventional conditions or conditions recommended by the manufacturer. Those reagents or instruments not specified by the manufacturer can be obtained as conventional products through commercial purchase.

[0098] It should be noted that the following "parts" and "%" are based on mass without special instructions.

[0099] The electroplating-resistant compositions of Examples 1 to 10 and Comparative Examples 1 to 9 were obtained by mixing the respective components shown in Tables 1 and 2 at the compounding ratios (mass basis) shown.

[0100]

Table 1

[0101]

[0102] - indicates not contained

[0103]

Table 2

[0104]

[0105] - indicates not contained

[0106] Remarks:

[0107] A-1: Phenolic novolac type epoxy-modified acrylic resin prepared in Synthesis Example 1 below (solid content 64%)

[0108] A-2: Cresol novolac type epoxy-modified acrylic resin prepared in Synthesis Example 2 below (solid content 64%)

[0109] B: Talc powder, D50 = 2.5 μm, flaky, HD25, manufactured by Fushi (Shanghai) Trading Co., Ltd.

[0110] C-1: Barium sulfate, D50 = 0.5 μm, spherical, BRILLANT-A1, Guangzhou Jimei Bailang Chemical Co., Ltd.

[0111] C-2: Calcium carbonate, D50 = 1 μm, spherical, ML-2800, manufactured by Foshan Shunde Meilin Chemical Co., Ltd.

[0112] C-3: Silicon dioxide, D50 = 2 μm, spherical, CS-1002A, manufactured by Jiangsu Lianrui New Materials Co., Ltd.

[0113] D: Polymerizable monomer, MT3501A, manufactured by Zhangjiagang Dongya Daisheng Chemical Co., Ltd., a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate

[0114] Color paste: Phthalocyanine blue, manufactured by Lianyungang Daisheng Colorant Co., Ltd.

[0115] Melamine: MELAMINE, manufactured by Guangzhou Jiachun Electronics Co., Ltd.

[0116] Defoamer: KSZ-66, manufactured by Zhejiang Shin-Etsu Fine Chemical Co., Ltd.

[0117] Photoinitiator A: EAB, 4,4'-bis(diethylamino)benzophenone, manufactured by BASF Germany

[0118] Sensitizer: GR-ITX, manufactured by Hubei Goodrun Technology Co., Ltd.

[0119] Photoinitiator B: #907, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, manufactured by BASF Germany

[0120] Bisphenol A epoxy resin: 128E, manufactured by Nan Ya Electronic Materials (Kunshan) Co., Ltd.

[0121] TGIC-type epoxy resin: TGIC JF-77B, manufactured by Huangshan Jinfeng Industry Co., Ltd.

[0122] Synthesis Example 1

[0123] 950 parts (number of glycidyl groups (total number of aromatic rings): 5.0 moles) of phenol novolac epoxy resin (manufactured by DIC Corporation, EPICLON N-770, softening point 65 - 75°C, epoxy equivalent 190), 360 parts (5.0 moles) of acrylic acid, and 1.5 parts of hydroquinone were added to 650 parts of diethylene glycol monoethyl ether acetate, heated to 100°C and stirred until uniformly dissolved. Then, 4.3 parts of triphenylphosphine were added, heated to 110°C, reacted for 2 hours, and then an additional 1.6 parts of triphenylphosphine were added, the temperature was raised to 120°C, and the reaction was further carried out for 12 hours. 525 parts of aromatic hydrocarbon (SOLVESSO 150) and 608 parts (4.0 moles) of tetrahydrophthalic anhydride were added to the obtained reaction solution, and the reaction was carried out at 110°C for 4 hours. Further, 770 parts (5.4 moles) of glycidyl methacrylate were added to the obtained reaction solution, and the reaction was carried out at 115°C for 4 hours to obtain a solution of a phenol novolac-type epoxy-modified acrylic resin with a solid content acid value of 58 mgKOH / g and a solid content of 64%.

[0124] Synthesis Example 2

[0125] Into 650 parts of diethylene glycol monoethyl ether acetate, 1070 parts (the number of glycidyl groups (total number of aromatic rings): 5.0 moles) of o-cresol novolac type epoxy resin (manufactured by DIC Corporation, EPICLON N-695, softening point 95 °C, epoxy equivalent 214), 360 parts (5.0 moles) of acrylic acid, and 1.5 parts of hydroquinone were added, heated to 100 °C and stirred until uniformly dissolved. Then, 4.3 parts of triphenylphosphine were added, heated to 110 °C, reacted for 2 hours, and then an additional 1.6 parts of triphenylphosphine were added, the temperature was raised to 120 °C, and the reaction was further carried out for 12 hours. 525 parts of aromatic hydrocarbon (SOLVESSO 150) and 608 parts (4.0 moles) of tetrahydrophthalic anhydride were added to the obtained reaction solution, and the reaction was carried out at 110 °C for 4 hours. Further, 142.0 parts (1.0 mole) of glycidyl methacrylate were added to the obtained reaction solution, and the reaction was carried out at 115 °C for 4 hours to obtain a solution of a cresol novolac type epoxy-modified acrylic resin with a solid content acid value of 83 mgKOH / g and a solid content of 64%.

[0126] The following performance evaluations were carried out on the anti-electroplating compositions obtained in Examples 1 to 10 and Comparative Examples 1 to 6.

[0127] Evaluation method and criteria

[0128] (1) Evaluation of resolution

[0129] The anti-electroplating compositions of the above Examples and Comparative Examples were coated over the entire surface of the solar cell wafer, dried at 80 °C for 15 minutes, cooled to room temperature, and a resin layer with a thickness of 10 μm was formed. For the upper surface (exposed surface) of the dried composition, a DI exposure machine (Ledia6 manufactured by SCREEN Corporation) was used, and the exposure pattern was designed with line / space of 10 μm / 10 μm, 20 μm / 20 μm, 30 μm / 30 μm, 40 μm / 40 μm, 50 μm / 50 μm, 60 μm / 60 μm, 70 μm / 70 μm, 80 μm / 80 μm, 90 μm / 90 μm, 100 μm / 100 μm, 200 μm / 200 μm, and exposed with an exposure amount of 405 nm light source output power 100% and 400 mJ / cm 2 After development for 60 seconds under the condition of a spray pressure of 2 kg using a 1% by mass aqueous sodium carbonate solution at 30 °C, an evaluation substrate was obtained.

[0130] The developed opening grooves were observed under a microscope, and the width of the grooves was measured and recorded as the evaluation of resolution in Tables 1 and 2.

[0131] (2) Evaluation of copper anti-electroplating performance

[0132] The anti - electroplating compositions of the above - mentioned examples and comparative examples were coated uniformly on the surface of the solar cell wafers, dried at 80 °C for 20 minutes, cooled to room temperature, and a resin layer with a thickness of 10 μm was formed. For the upper surface (exposed surface) of the above - dried compositions, a DI exposure machine (Ledia6 manufactured by SCREEN Corporation) was used, with a light source of 405 nm, an output power of 100%, and an exposure dose of 400 mJ / cm 2 for pattern exposure. After development for 60 seconds under the condition of a spray pressure of 2 kg using a 1% by mass aqueous sodium carbonate solution at 30 °C, an evaluation substrate was obtained.

[0133] The evaluation substrates obtained as above were subjected to an electroplated copper process to evaluate the anti - electroplated copper performance.

[0134] In the electroplated copper process, the electroplating solution used was prepared as follows: copper sulfate (CuSiO4·5H2O) 200 g / L, sulfuric acid (H2SO4) 80 g / L, chloride ions (Cl-) 70 mg / L, inhibitor 13 ml / L, brightener 30 ml / L, and leveling agent 20 ml / L. The electroplating operation conditions were: temperature 20 - 25 °C, current density 5 A / dm 2 , strong stirring intensity, and an electroplated copper thickness of 10 μm.

[0135] The evaluation items were: 1) Whether there was peeling of the anti - plating composition on the surface of the cell wafer after copper plating and whether there was cross - short - circuit of the copper grid lines; 2) After copper plating, a 3M tape stress stripping test was carried out to see if there was peeling of the copper grid lines.

[0136] The evaluation criteria were as follows:

[0137] There was no peeling of the anti - plating composition on the surface of the cell wafer after copper plating, no cross - short - circuit of the copper grid lines, and no peeling of the copper grid lines during the 3M tape stress stripping test ○

[0138] There was no peeling of the anti - plating composition on the surface of the cell wafer after copper plating, no cross - short - circuit of the copper grid lines, but there was peeling of the copper grid lines during the 3M tape stress stripping test △

[0139] There was peeling of the anti - plating composition on the surface of the cell wafer after copper plating or there was cross - short - circuit of the copper grid lines ×

[0140] (3) Evaluation of stripping and cleaning

[0141] The evaluation substrates obtained in the above (2) were evaluated for stripping and cleaning performance according to the following two conditions respectively.

[0142] A 5% by mass sodium hydroxide solution was kept at a constant temperature of 60 °C for 5 min

[0143] A 5% by mass sodium hydroxide solution was kept at a constant temperature of 70 °C for 5 min

[0144] The evaluation criteria were as follows:

[0145] After soaking in the stripping solution, there is no residue on the substrate surface ○

[0146] After soaking in the stripping solution, there is slight residue, and there is no residue after water washing △

[0147] After soaking in the stripping solution, there is residue, and there is still residue after water washing ×

[0148] The results of the above evaluation tests are shown together in Table 1 and Table 2 above.

[0149] As is clearly seen from Table 1, in Examples 1 to 10 which contain 4 to 50 parts by mass of (B) talc and 5 to 55 parts by mass of (C) inorganic filler other than talc relative to 100 parts by mass of the solid content of the polyfunctional acrylic resin (A) and do not contain epoxy resin, the evaluations of resolution, electroless copper plating resistance, and stripping performance are all excellent results. Among them, compared with Example 2 which uses both A-2 cresol novolak type epoxy-modified acrylic resin and A-1 phenol novolak type epoxy-modified acrylic resin as the polyfunctional acrylic resin (A), the evaluations of the electroless copper plating resistance and the stripping property at 60 °C of Example 1 which uses only A-1 phenol novolak type epoxy-modified acrylic resin are more excellent results. Compared with Examples 1-2, 4-5, and 8-9 which use barium sulfate or calcium carbonate as the inorganic filler (C) other than talc, the evaluations of the electroless copper plating resistance of Examples 3, 6, and 10 which use silica are more excellent results.

[0150] In contrast, as is clearly seen from Table 2, Comparative Example 1 containing epoxy resin does not obtain excellent results in the stripping property evaluation and cannot meet the requirement of improving the stripping property of the present invention like Examples 1-10. In addition, Comparative Examples 2-3 with too little content of (B) talc and too high content of (C) inorganic filler other than talc have poor electroless copper plating resistance. Comparative Examples 4-6 with too high content of (B) talc have poor electroless copper plating resistance, and although the stripping property at 60 °C is at a practical level, it is significantly inferior to that of the examples. Comparative Examples 7-9 with appropriate content of (B) talc but too high content of (C) inorganic filler other than talc have poor resolution and electroless copper plating resistance.

[0151] From these results, it can be determined that the electroless plating composition of the present invention has high resolution, less development residue, excellent electroless copper plating resistance and stripping performance by containing 4 to 50 parts by mass of (B) talc and 5 to 55 parts by mass of (C) inorganic filler other than talc and not containing epoxy resin, and is suitable for use in photoresists used in the manufacture of solar cell electrodes.

[0152] It should be noted that although the technical solutions of the present invention are introduced by specific examples, those skilled in the art can understand that the present invention should not be limited thereto.

[0153] The embodiments of the present invention have been described above. The above description is exemplary and not exhaustive, and is also not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to technologies in the market, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. An anti - electroplating composition, characterized in that, Comprising (A) a polyfunctional acrylic resin, (B) talc, and (C) an inorganic filler other than talc, and not containing an epoxy resin, wherein, based on 100 parts by mass of the solid content of (A) the polyfunctional acrylic resin, the (B) talc is 4 to 50 parts by mass, and the (C) inorganic filler other than talc is 5 to 55 parts by mass. The (A) polyfunctional acrylic resin comprises an epoxy-modified acrylic resin. The epoxy-modified acrylic resin is: a resin obtained by reacting a phenol novolac type epoxy resin with (meth)acrylic acid and adding tetrahydrophthalic anhydride to the hydroxyl groups present in the side chain; or a resin obtained by further adding glycidyl (meth)acrylate to this resin.

2. The anti - electroplating composition according to claim 1, characterized in that, The (A) polyfunctional acrylic resin has, in addition to a plurality of (meth)acryloyl groups, a plurality of carboxyl groups in the molecule.

3. The anti - electroplating composition according to claim 1, characterized in that, The average particle size (D50) of the (B) talc is 1.0 - 20.0 μm.

4. The anti - electroplating composition according to claim 1 or 2, characterized in that, The (C) inorganic filler other than talc is a spherical powder.

5. The anti - electroplating composition according to claim 1 or 2, characterized in that, The (C) inorganic filler other than talc comprises at least any one selected from silica, barium sulfate, and calcium carbonate.

6. The anti - electroplating composition according to claim 5, characterized in that, The (C) inorganic filler other than talc comprises silica.

7. The anti - electroplating composition according to claim 6, characterized in that, The average particle size (D50) of the silica is 0.1 to 10.0 μm.

8. Use of the anti - electroplating composition according to any one of claims 1 to 7 in manufacturing an electrode of a solar cell.

9. A dry film, characterized in that, It is obtained by coating the anti-electroplating composition according to any one of claims 1 to 7 on a carrier film and drying.

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