Curable composition for preventing sulfuration, adhesive sheet and film, and member for display device

Abstract

To provide a curable composition for preventing sulfuration that is capable of suppressing sulfuration, and an adhesive sheet and a film obtained from the composition.SOLUTION: This curable composition for preventing sulfuration is a curable composition used for preventing sulfuration of a metal, comprising at least a thiourea compound and a polymerizable component, wherein the thiourea compound has a cyclic structure, the cyclic structure has a structure including an -N-C(=S)-N- bond, the polymerizable component is at least one selected from the group consisting of acrylic polymers and monofunctional monomers, and the thiourea compound is contained in an amount of 0.01 pt.mass or more and 0.1 pt.mass or less per 100 pts.mass of the polymerizable component.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a curable composition for preventing sulfidation, a pressure-sensitive adhesive sheet and film, and a member for a display device. [Background technology]

[0002] In recent years, touch sensor films, which have metal mesh pattern wiring made of silver or copper formed on a resin film, have been used as touch panels for mobile terminals, etc. Such touch sensor films are highly flexible and tend to improve touch sensitivity.

[0003] A touch sensor film can be manufactured, for example, by bonding it to another component (e.g., glass, a polarizing plate, etc.) using an adhesive sheet, and various adhesive sheets to be used for this purpose are being studied (see, for example, Patent Document 1, etc.). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-160416 Summary of the Invention [Problem to be solved by the invention]

[0005] However, metal mesh pattern wiring made of silver or copper, such as in touch sensor films, can be susceptible to sulfuration, which can reduce the sensitivity of the touch sensor and cause malfunctions. Sulfuration can occur, for example, due to the environment in which a device equipped with a touch sensor film is used (e.g., hot springs) or sulfur components generated from rubber or other components installed inside the device. Therefore, there has been a need to prevent sulfuration of metal mesh pattern wiring installed in touch sensor films and the like.

[0006] The present invention has been made in view of the above, and has an object to provide a sulfuration-preventing curable composition that can suppress sulfuration, as well as a pressure-sensitive adhesive sheet and film obtained from the composition. [Means for solving the problem]

[0007] From the above viewpoints, the present inventors have investigated imparting a sulfuration prevention function to an adhesive sheet or the like to be attached to a metal layer having wiring of a metal mesh pattern. As a result, the present inventors have found that sulfuration of the metal layer can be prevented by forming an adhesive sheet or film using a composition containing a thiourea compound having a specific structure, and have completed the present invention.

[0008] That is, the present invention includes, for example, the subject matter described in the following sections. Item 1 A curable composition used to prevent sulfidation of metals, comprising: Contains at least a thiourea compound and a polymerizable component, The thiourea compound has a cyclic structure, the cyclic structure has a structure containing an —NC(═S)—N— bond, the polymerizable component is at least one selected from the group consisting of an acrylic polymer and a monofunctional monomer, The curable composition for preventing sulfurization, wherein the thiourea compound is contained in an amount of 0.01 part by mass or more and 0.1 part by mass or less per 100 parts by mass of the polymerizable component. Section 2 Item 2. The sulfidation-preventing curable composition according to Item 1, wherein the metal is silver or copper, and the metal layer has a mesh structure. Section 3 Item 3. A pressure-sensitive adhesive sheet comprising a cured product of the curable composition for preventing sulfidation according to Item 1 or 2. Section 4 Item 3. A coating comprising a cured product of the curable composition for preventing sulfidation according to Item 1 or 2. Section 5 A display device member including a touch sensor film, The touch sensor film comprises a laminate including the pressure-sensitive adhesive sheet according to item 3 and a metal layer having a mesh structure; the pressure-sensitive adhesive sheet is attached to at least one surface of the metal layer, The metal layer is silver or copper. Section 6 A display device member including a touch sensor film, The touch sensor film comprises a laminate including the film according to item 4 and a metal layer having a mesh structure; the coating is formed on at least one surface of the metal layer; The metal layer is silver or copper. Section 7 Item 6. A display device comprising the member for a display device according to item 5. Section 8 Item 7. A display device comprising the member for a display device according to Item 6. [Effects of the Invention]

[0009] The sulfuration-preventing curable composition of the present invention can form a pressure-sensitive adhesive sheet or film that can inhibit the sulfuration of metals.

[0010] When a pressure-sensitive adhesive sheet or film obtained from the sulfuration-preventing curable composition of the present invention is provided on a metal layer, sulfuration of the metal layer can be suppressed. DETAILED DESCRIPTION OF THE INVENTION

[0011]

[0023] In the present specification, the terms "contain" and "comprise" include the concepts of "contain," "comprise," "consist essentially of," and "consist only of."

[0012] 1. Curable composition for preventing sulfurization The sulfuration-preventing curable composition of the present invention is used to prevent the sulfuration of metals and contains at least a thiourea compound and a polymerizable component. The thiourea compound has a cyclic structure, and the cyclic structure contains an -NC(=S)-N- bond. The polymerizable component is at least one selected from the group consisting of acrylic polymers and monofunctional monomers. In the sulfuration-preventing curable composition of the present invention, the thiourea compound is contained in an amount of 0.01 part by mass or more and 0.1 part by mass or less per 100 parts by mass of the polymerizable component.

[0013] The sulfuration-preventing curable composition of the present invention can form a pressure-sensitive adhesive sheet or film that can suppress the sulfuration of metal. Therefore, the pressure-sensitive adhesive sheet or film obtained using the sulfuration-preventing curable composition of the present invention is suitable for use in a touch sensor film having a metal layer with a mesh structure, and by laminating the pressure-sensitive adhesive sheet to the metal layer or by forming a film on the metal layer, the sulfuration of the metal layer can be suppressed, making the pressure-sensitive adhesive sheet or film particularly suitable for use in a display device component that includes a touch sensor film.

[0014] (Polymerizable component) The polymerizable component contained in the sulfurization-preventing curable composition is at least one selected from the group consisting of acrylic polymers and monofunctional monomers. One embodiment of the polymerizable component is polymerizable component A containing an acrylic polymer and a monofunctional monomer, and another embodiment of the polymerizable component is polymerizable component B containing a monofunctional monomer but not an acrylic polymer. When the polymerizable component contained in the sulfurization-preventing curable composition is polymerizable component A, the sulfurization-preventing curable composition can be used as a raw material for producing a pressure-sensitive adhesive sheet. When the polymerizable component contained in the sulfurization-preventing curable composition is polymerizable component B, the sulfurization-preventing curable composition can be used as a raw material for producing a coating.

[0015] The polymerizable component does not include a polyfunctional monomer, which will be described later.

[0016] Polymerizable component A Polymerizable component A includes an acrylic polymer and a monofunctional monomer. Therefore, polymerizable component A is, for example, a solution in which an acrylic polymer is dissolved in a monofunctional monomer. Examples of the acrylic polymer include a wide range of known acrylic polymers used to form pressure-sensitive adhesive sheets. For example, the acrylic polymer may be a polymer containing at least a (meth)acrylic acid ester unit. In other words, the acrylic polymer is a polymer of a monomer containing a (meth)acrylic acid ester.

[0017] Examples of the (meth)acrylic acid ester include (meth)acrylates having a linear or branched alkyl group.

[0018] In this specification, "(meth)acrylic" means "acrylic" or "methacrylic." For example, "(meth)acrylate" means "acrylate" or "methacrylate."

[0019] Examples of (meth)acrylic acid esters include alkyl (meth)acrylates having a linear, cyclic, or branched alkyl group with 10 to 18 carbon atoms. The linear, cyclic, or branched alkyl group with 10 to 18 carbon atoms preferably has 12 or more carbon atoms, and more preferably has 14 or more carbon atoms. The alkyl group with 10 to 18 carbon atoms preferably does not have a hydroxyl group or a carboxyl group.

[0020] Specific examples of the alkyl(meth)acrylate having a linear, cyclic, or branched structure and having 10 to 18 carbon atoms include isobornyl(meth)acrylate, lauryl(meth)acrylate, isomistyryl(meth)acrylate, isostearyl(meth)acrylate, isotridecyl(meth)acrylate, isopentadecyl(meth)acrylate, isohexadecyl(meth)acrylate, isoheptadecyl(meth)acrylate, etc. Among these, at least one selected from the group consisting of isostearyl(meth)acrylate and isobornyl(meth)acrylate is preferred.

[0021] In addition to the above, the (meth)acrylic acid ester may also include a (meth)acrylate having an alkyl group with 9 or less carbon atoms or a (meth)acrylate having an aromatic ring, and among these, the (meth)acrylic acid ester preferably includes a (meth)acrylate having an alkyl group with 9 or less carbon atoms. The alkyl group with 9 or less carbon atoms preferably does not have a hydroxyl group or a carboxyl group.

[0022] Examples of (meth)acrylates having an alkyl group or aromatic ring having 9 or less carbon atoms include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, isopropyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, and benzyl (meth)acrylate. Among these, in terms of ease of control of adhesive properties, (meth)acrylates having an alkyl group having 2 to 9 carbon atoms are more preferred, (meth)acrylates having an alkyl group having 3 to 9 carbon atoms are even more preferred, and (meth)acrylates having an alkyl group having 4 to 9 carbon atoms are particularly preferred. A preferred specific example of a (meth)acrylate having an alkyl group or aromatic ring having 9 or less carbon atoms is 2-ethylhexyl (meth)acrylate.

[0023] The (meth)acrylic acid ester units contained in the acrylic polymer may be of one type or two or more types.

[0024] The acrylic polymer may contain units other than (meth)acrylic acid ester units, for example, vinyl monomer units having a cyclic or acyclic substituent containing a nitrogen atom. That is, the acrylic polymer may be a polymer of monomers including a (meth)acrylic acid ester and a vinyl monomer having a cyclic or acyclic substituent containing a nitrogen atom.

[0025] Specific examples of vinyl monomers having an acyclic substituent containing a nitrogen atom include (meth)acrylamide and N-substituted (meth)acrylamide. Examples of N-substituted (meth)acrylamides include (meth)acrylamides in which one or two alkyl groups are substituted on the nitrogen atom. In N-substituted (meth)acrylamides, the alkyl group may be, for example, an alkyl group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably an alkyl group having 1 or 2 carbon atoms. When two alkyl groups are substituted on the nitrogen atom, the alkyl groups may be the same or different, and preferably the alkyl groups are the same.

[0026] In this specification, "(meth)acrylamide" means "acrylamide" or "methacrylamide".

[0027] Specific examples of N-substituted (meth)acrylamides include N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, and tert-octylacrylamide.

[0028] Specific examples of vinyl monomers having a cyclic substituent containing a nitrogen atom include acryloylmorpholine.

[0029] The vinyl monomer unit having a cyclic substituent containing a nitrogen atom contained in the acrylic polymer may be one or two or more types.

[0030] The acrylic polymer may contain units other than the above-mentioned units, for example, a monomer unit having a crosslinkable reactive group. Examples of monomers for forming such a monomer unit having a crosslinkable reactive group include (meth)acrylates having a hydroxyl group and (meth)acrylates having a carboxyl group.

[0031] Examples of (meth)acrylates having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2,2-dimethyl-2-hydroxyethyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, and polyalkylene glycol mono(meth)acrylate. Of these, 4-hydroxybutyl (meth)acrylate is preferred. Examples of the (meth)acrylate having a carboxyl group include acrylic acid and methacrylic acid.

[0032] The acrylic polymer is preferably a polymer of a monomer containing at least one selected from the group consisting of alkyl(meth)acrylates having a linear, cyclic, or branched alkyl group with 10 to 18 carbon atoms, (meth)acrylates having an alkyl group with 9 or less carbon atoms, vinyl monomers having an acyclic substituent containing a nitrogen atom, vinyl monomers having a cyclic substituent containing a nitrogen atom, and (meth)acrylates having a hydroxyl group. Examples include polymers of a monomer containing at least one selected from the group consisting of alkyl(meth)acrylates having a linear, cyclic, or branched alkyl group with 10 to 18 carbon atoms, (meth)acrylates having an alkyl group with 9 or less carbon atoms, and vinyl monomers having an acyclic substituent containing a nitrogen atom.

[0033] The acrylic polymer may have an alkyl (meth)acrylate unit content of 15 parts by mass or more, preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and even more preferably 30 parts by mass or more, per 100 parts by mass of the acrylic polymer, and ...80 parts by mass or less, preferably 75 parts by mass or less, more preferably 70 parts by mass or less, and even more preferably 60 parts by mass or less.

[0034] The acrylic polymer may have a content of (meth)acrylate units having an alkyl group having 9 or less carbon atoms of 15 parts by mass or more, preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and even more preferably 30 parts by mass or more, relative to 100 parts by mass of the acrylic polymer, and may have a content of 70 parts by mass or less, preferably 60 parts by mass or less, more preferably 50 parts by mass or less, and even more preferably 45 parts by mass or less.

[0035] The content of the vinyl monomer unit having an acyclic substituent containing a nitrogen atom in the acrylic polymer may be 1 part by mass or more, preferably 3 parts by mass or more, more preferably 5 parts by mass or more, and even more preferably 7 parts by mass or more, relative to 100 parts by mass of the acrylic polymer, and may be 30 parts by mass or less, preferably 25 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 15 parts by mass or less.

[0036] The acrylic polymer may have a content of vinyl monomer units having a cyclic substituent containing a nitrogen atom of 30 parts by mass or less, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, or may be 0 parts by mass, relative to 100 parts by mass of the acrylic polymer.

[0037] The acrylic polymer preferably contains 20 parts by mass or less of the (meth)acrylate having a hydroxyl group, more preferably 10 parts by mass or less, and even more preferably 5 parts by mass or less, per 100 parts by mass of the acrylic polymer. The content of the (meth)acrylate having a hydroxyl group may be 0 parts by mass.

[0038] The weight-average molecular weight of the acrylic polymer is not particularly limited, and from the viewpoint of preventing a decrease in adhesive strength in the pressure-sensitive adhesive sheet, it can be, for example, 100,000 to 2,000,000, and more preferably 300,000 to 1,000,000. Note that the weight-average molecular weight referred to in the present invention refers to the weight-average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[0039] There are no particular limitations on the GPC apparatus used in the GPC method. Commercially available GPC measuring instruments, such as the LC-2000Plus series manufactured by JASCO Corporation, with detectors such as RI-2031Plus and UV-2075Plus, can be used. In this case, for example, a GPC column consisting of four columns connected together, including "Shodex KF801," "Shodex KF803L," "Shodex KF800L," and "Shodex KF800D" manufactured by Showa Denko K.K., can be used. The column temperature can be set to 40°C. Tetrahydrofuran is used as the eluent, and measurements are performed at a flow rate of 1.0 ml / min. Typically, a calibration curve is prepared using standard polystyrene, and the weight-average molecular weight (Mw) can be calculated in terms of polystyrene.

[0040] The glass transition temperature (Tg) of the acrylic polymer is not particularly limited and can be, for example, from -60 to 0°C, preferably from -50 to -10°C, and more preferably from -40 to -20°C.

[0041] The method for adjusting the glass transition temperature of the acrylic polymer is not particularly limited, and the glass transition temperature can be adjusted to a desired range by, for example, changing the type and composition ratio of the monomers constituting the acrylic polymer (P). In the present invention, the glass transition temperature of the acrylic polymer refers to Tg calculated by the following Fox formula based on the composition of the monomers used in the synthesis of the polymer. Fox formula: 1 / Tg = (W1 / Tg1) + (W2 / Tg2) + + (Wm / Tgm) where W1+W2+···+Wm=1 In the formula, Tg is the glass transition temperature (unit: K) of the acrylic polymer, Tg1, Tg2, ..., Tgm are the glass transition temperatures of the respective homopolymers of m types of monomers (m is an integer) that constitute the acrylic polymer, and W1, W2, ..., Wm are the mass fractions of each structural unit in the acrylic polymer. Note that Tg1 and W1 correspond to each other; that is, the monomer that constitutes the homopolymer that exhibits the glass transition temperature of Tg1 is the same as the monomer that forms the structural unit whose mass fraction is W1. Similarly, Tg2 and W2, ..., Tgm and Wm correspond to each other.

[0042] The glass transition temperature of the homopolymer can be determined, for example, from the value described in the Polymer Handbook, 4th Edition (Wiley-Interscience, 2003). If no such reference is found, the glass transition temperature of the homopolymer can be measured, for example, by a differential scanning calorimeter (DSC). The DSC measurement conditions are as follows: 5 mg of sample, under a nitrogen atmosphere, the temperature is increased from -100°C to 200°C at a rate of 5°C / min in the first measurement (1st run), then cooled to -100°C at a rate of 5°C / min, and then increased from -100°C to 200°C at a rate of 5°C / min in the second measurement (2nd run). Here, the glass transition temperature refers to the intersection of the extension of the baseline on the lower temperature side of the region where the baseline of the DSC curve measured when the temperature is raised from -100°C to 200°C changes to a sigmoid shape in the endothermic direction and the tangent to the inflection point of the sigmoid.

[0043] The acrylic polymer can be produced by a known method. For example, the acrylic polymer can be produced by polymerizing a monomer mixture for forming each structural unit by a known polymerization method. In this case, the acrylic polymer may be a partially polymerized product, that is, a state in which a portion of the monomer used in the polymerization remains unpolymerized. The remaining unpolymerized monomer corresponds to the monofunctional monomer contained in the polymerizable component A.

[0044] Therefore, the polymerization component A can be prepared by a method for obtaining a partial polymer of an acrylic polymer. The polymerization component A can also be called a syrup of an acrylic polymer.

[0045] The polymerization method for obtaining the acrylic polymer or a partially polymerized product thereof may be, for example, solution polymerization, bulk polymerization, suspension polymerization, emulsion polymerization, etc. The acrylic polymer may also be obtained from a commercial product.

[0046] As described above, the monofunctional monomer contained in polymerizable component A can be an unreacted polymerizable monomer derived from the production of the partial polymer of the acrylic polymer. Therefore, the monofunctional monomer contained in polymerizable component A is a monomer for constituting the acrylic polymer, and examples thereof include monomers including (meth)acrylic acid esters and vinyl monomers having a cyclic or acyclic substituent containing a nitrogen atom, the types of which are as described above.

[0047] Therefore, examples of the monofunctional monomer contained in polymerizable component A include alkyl(meth)acrylates having a linear, cyclic, or branched alkyl group with 10 to 18 carbon atoms, (meth)acrylates having an alkyl group with 9 or less carbon atoms, vinyl monomers having a non-cyclic substituent containing a nitrogen atom, vinyl monomers having a cyclic substituent containing a nitrogen atom, and (meth)acrylates having a crosslinkable functional group.

[0048] The polymerizable component A does not contain a polyfunctional monomer, which will be described later.

[0049] The polymerizable component A may contain components other than the acrylic polymer and the monofunctional monomer, or may consist only of the acrylic polymer and the monofunctional monomer. As described above, the polymerizable component A is preferably a product obtained by polymerizing a partial polymer of the acrylic polymer. In this case, the polymer fraction of the polymerizable component A is not particularly limited. The polymer fraction is the content (mass %) of the resin component relative to the total mass of the resin components (acrylic polymer and monofunctional monomer). The polymer fraction can be, for example, 1 to 50 mass %, and preferably 20 to 40 mass %.

[0050] Polymerizable component B The polymerizable component B includes a monofunctional monomer, such as a (meth)acrylic acid ester or a vinyl monomer having a cyclic or acyclic substituent containing a nitrogen atom.

[0051] Examples of the (meth)acrylic acid ester contained in the polymerization component B include the aforementioned alkyl (meth)acrylates having a linear, cyclic, or branched alkyl group with 10 to 18 carbon atoms, and (meth)acrylates having an alkyl group with 9 or less carbon atoms.

[0052] The types of vinyl monomers having a cyclic or acyclic substituent containing a nitrogen atom contained in polymerization component B are the same as those described above. Accordingly, specific examples of vinyl monomers having an acyclic substituent containing a nitrogen atom include (meth)acrylamide and N-substituted (meth)acrylamide. Specific examples of N-substituted (meth)acrylamides include N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, and tert-octylacrylamide. Specific examples of vinyl monomers having a cyclic substituent containing a nitrogen atom include acryloylmorpholine.

[0053] Polymerization component B is preferably a mixture of a vinyl monomer having a cyclic substituent containing a nitrogen atom and a vinyl monomer having an acyclic substituent containing a nitrogen atom. The content ratio of the two is not particularly limited. For example, the content ratio of the vinyl monomer having a cyclic substituent containing a nitrogen atom relative to the total amount of the vinyl monomer having a cyclic substituent containing a nitrogen atom and the vinyl monomer having an acyclic substituent containing a nitrogen atom can be 5% by mass or more, preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 40% by mass or more, and can be 95% by mass or less, preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 70% by mass or less, and particularly preferably 60% by mass or less.

[0054] Polymerizable component B may contain components other than monofunctional monomers, or may consist solely of monofunctional monomers. Polymerizable component B does not contain polyfunctional monomers, which will be described later.

[0055] (Thiourea compounds) The thiourea compound contained in the sulfuration-preventing curable composition of the present invention is a compound having a cyclic structure. Such a cyclic structure has a structure containing an -NC(=S)-N- bond. That is, the thiourea compound is a compound having a cyclic structure containing an -NC(=S)-N- bond in the molecule. By including a thiourea compound in the sulfuration-preventing curable composition of the present invention, the resulting pressure-sensitive adhesive sheet or film can suppress sulfuration of metals.

[0056] In the thiourea compound having the cyclic structure, the nitrogens (N) at both ends of -NC(=S)-N-, together with the C=S bond to which they are bonded, can be bonded to each other via another divalent group to form a saturated ring. Specifically, the thiourea compound can be a compound having a structure represented by the following formula (1):

[0057] [ka]

[0058] Here, in the formula (1), R is -(CH2) n -, and n represents an integer of 2 to 4.

[0059] In the thiourea compound having the structure represented by the formula (1), the nitrogens (N) at both ends of -NC(=S)-N-, together with the C=S bond to which they are bonded, form -(CH2) n - are bonded to each other via an - to form a saturated ring.

[0060] Further specific examples of the thiourea compound include 1,3-trimethylene-2-thiourea and ethylenethiourea.

[0061] The thiourea compound can be produced by a known method, or can be obtained from a commercial product.

[0062] The sulfuration-preventing curable composition may contain one or more thiourea compounds, and may also contain other thiourea compounds as long as the effects of the present invention are not impaired.

[0063] The thiourea compound is contained in an amount of 0.01 part by mass or more and 0.1 part by mass or less relative to 100 parts by mass of the polymerizable component, whereby the sulfuration-preventing curable composition can form an adhesive sheet or film that can inhibit the sulfuration of metals.

[0064] When the polymerizable component is the polymerizable component A, the thiourea compound is preferably contained in an amount of 0.01 part by mass or more, more preferably 0.02 part by mass or more, and even more preferably 0.03 part by mass or more, relative to 100 parts by mass of the total amount of the polymerizable component A, and is preferably contained in an amount of 0.1 part by mass or less, more preferably 0.09 part by mass or less, even more preferably 0.08 part by mass or less, and particularly preferably 0.07 part by mass or less.

[0065] When the polymerizable component is the polymerizable component B, the thiourea compound is contained in an amount of preferably 0.01 part by mass or more, more preferably 0.02 part by mass or more, and even more preferably 0.03 part by mass or more, relative to 100 parts by mass of the total amount of the polymerizable component B, and is also contained in an amount of preferably 0.1 part by mass or less, more preferably 0.09 part by mass or less, even more preferably 0.08 part by mass or less, and particularly preferably 0.07 part by mass or less.

[0066] (polyfunctional monomer) The sulfur-preventing curable composition preferably contains a polyfunctional monomer. Examples of the polyfunctional monomer include compounds having two or more polymerizable double bonds in the molecule. The polyfunctional monomer has two or more polymerizable double bonds (e.g., radically polymerizable double bonds), preferably two or more but less than five, and more preferably two or more but less than four.

[0067] Examples of polyfunctional monomers include bifunctional monomers (monomers having two polymerizable double bonds), such as polyethylene glycol diacrylate, polypropylene diacrylate, alkyl diacrylate, polytetramethylene glycol diacrylate, polypropylene glycol diacrylate, dioxane diacrylate, tricyclodecanol diacrylate, and fluorene diacrylate. Examples of polyfunctional monomers include trifunctional or higher functional monomers, such as alkoxylated trimethylolpropane triacrylate, alkoxylated glycerin triacrylate, caprolactone-modified isocyanurate triacrylate, pentaerythritol acrylate, alkoxylated pentaerythritol acrylate, (alkoxylated) pentaerythritol acrylate, (alkoxylated) ditrimethylolpropane acrylate, (alkoxylated) dipentaerythritol acrylate, (ethoxylated) polyglycerin acrylate, polyfunctional urethane acrylate, and polyfunctional oligomers such as acrylic-terminated polybutadiene (olefin).

[0068] When the polyfunctional monomer is a polyfunctional monomer having an alkylene glycol group in one molecule, the number of alkylene glycol groups in one molecule is preferably 1 to 20. Examples of such polyfunctional monomers include polyethylene glycol diacrylate and trimethylolpropane propylene oxide modified triacrylate.

[0069] Commercially available polyfunctional monomers include, for example, bifunctional polyethylene glycol acrylates such as "A-200" (polyethylene glycol #200 diacrylate) and "A-400" (polyethylene glycol #400 diacrylate) from the NK Ester series manufactured by Shin-Nakamura Chemical Co., Ltd., trifunctional "ATM-4PL" (pentaerythritol triacrylate), trifunctional monomer M310 (trimethylolpropane PO-modified triacrylate) and trifunctional monomer M321 (trimethylolpropane propylene oxide-modified triacrylate) manufactured by Toagosei Co., Ltd., and bifunctional monomer M211B (bisphenol A EO-modified diacrylate) manufactured by Toagosei Co., Ltd.

[0070] The polyfunctional monomer may have a bisphenol skeleton in one molecule, such as diacrylate of bisphenol A diglycidyl ether, diacrylate of propoxylated bisphenol A, and diacrylate of bisphenol F diglycidyl ether.

[0071] When the sulfuration-preventing curable composition contains a polyfunctional monomer, curing the sulfuration-preventing curable composition with active energy rays forms a crosslinked polymer, which tends to provide the pressure-sensitive adhesive sheet with excellent adhesive strength or to improve the strength of the film. The sulfuration-preventing curable composition can contain one type of polyfunctional monomer alone or two or more types.

[0072] The content of the polyfunctional monomer in the sulfurization-preventing curable composition is not particularly limited. For example, when the polymerizable component contained in the sulfurization-preventing curable composition is the polymerizable component A, the polyfunctional monomer may be contained in an amount of 5 parts by mass or less, preferably 3 parts by mass or less, more preferably 1 part by mass or less, even more preferably 0.5 parts by mass or less, and particularly preferably 0.3 parts by mass or less, per 100 parts by mass of the polymerizable component A. Furthermore, when the polymerizable component contained in the sulfurization-preventing curable composition is the polymerizable component A, the polyfunctional monomer is contained in an amount of 0.01 parts by mass or more, more preferably 0.03 parts by mass or more, and even more preferably 0.05 parts by mass or more, per 100 parts by mass of the polymerizable component A.

[0073] When the polymerizable component contained in the sulfurization-preventing curable composition is polymerizable component B, the polyfunctional monomer may be contained in an amount of 60 parts by mass or less, preferably 50 parts by mass or less, more preferably 45 parts by mass or less, even more preferably 40 parts by mass or less, and particularly preferably 35 parts by mass or less, per 100 parts by mass of the total mass of polymerizable component B and the polyfunctional monomer. When the polymerizable component contained in the sulfurization-preventing curable composition is polymerizable component B, the polyfunctional monomer is contained in an amount of 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 15 parts by mass or more, and particularly preferably 20 parts by mass or more, per 100 parts by mass of the total mass of polymerizable component B and the polyfunctional monomer.

[0074] (Curable composition for preventing sulfuration) As described above, the sulfurization-preventing curable composition contains a thiourea compound and polymerizable component A or polymerizable component B as essential components, and may also contain a polyfunctional monomer, a photopolymerization initiator, a silane coupling agent, a solvent, etc., as necessary. Furthermore, a dye or pigment may be added to the pressure-sensitive adhesive for the purpose of coloring. It is also preferable that the sulfurization-preventing curable composition does not contain a solvent, i.e., is solvent-free.

[0075] The photopolymerization initiator initiates polymerization of a polyfunctional monomer by irradiation with active energy rays. In this specification, "active energy rays" refers to electromagnetic waves or charged particle rays that have an energy quantum, and examples thereof include ultraviolet rays, electron beams, visible light, X-rays, and ion beams. Among these, ultraviolet rays or electron beams are preferred from the viewpoint of versatility, and ultraviolet rays are particularly preferred.

[0076] The type of photopolymerization initiator is not particularly limited, and a wide range of known photopolymerization initiators can be used. Examples of the photopolymerization initiator include acetophenone-based photopolymerization initiators such as 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl-phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropanone, 1-[4-(2-hydroxyethoxyl)-phenyl]-2-hydroxy-methylpropanone, and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methyl-1-propanone; acylphosphine oxide-based photopolymerization initiators such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and 2,4,6-trimethylbenzoyl)phenylphosphine oxide; intramolecular hydrogen abstraction photopolymerization initiators such as methyl benzoylformate and 4-methylbenzophenone; and oil-soluble polymerization initiators such as oxime ester-based photopolymerization initiators and cationic photopolymerization initiators. Among these, the photopolymerization initiator is preferably at least one selected from the group consisting of acetophenone-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, and oxime ester-based photopolymerization initiators.

[0077] Commercially available acetophenone-based photopolymerization initiators include EsacureOne (oligo(2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenylpropanone], photoinitiator manufactured by IGM Resins BV), Omnirad 651 (2,2-dimethoxy-2-phenylacetophenone, manufactured by IGM Resins BV), Omnirad 184 (1-hydroxycyclohexylphenylketone, manufactured by IGM Resins BV), and Omnirad 1173 (2-hydroxy-2-methyl-1-phenylpropanone, manufactured by IGM Resins BV). Commercially available acylphosphine oxide-based photopolymerization initiators include Omnirad 819 (bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, manufactured by IGM Resins BV) and Omnirad TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide, manufactured by IGM Resins BV). (manufactured by RESINS BV)

[0078] In the curable composition for preventing sulfurization, the content ratio of the photopolymerization initiator is not particularly limited, and is, for example, preferably 0.01 part by mass or more, more preferably 0.05 part by mass or more, and even more preferably 0.1 part by mass or more, relative to 100 parts by mass of the polymerizable component, and is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, even more preferably 3 parts by mass or less, and particularly preferably 1.5 parts by mass or less.

[0079] The method for preparing the curable composition for preventing sulfurization is not particularly limited, and for example, a wide variety of known methods can be adopted. For example, the curable composition for preventing sulfurization can be prepared by mixing polymerizable component A or polymerizable component B, a thiourea compound, and a polyfunctional monomer.

[0080] The sulfuration-preventing curable composition contains a specific thiourea compound and a polymerizable component, and thus has photocurability. For example, the sulfuration-preventing curable composition undergoes a curing reaction when exposed to active energy rays, and can form a pressure-sensitive adhesive sheet, a coating, or the like.

[0081] The sulfuration-preventing curable composition can form a pressure-sensitive adhesive sheet or film that can suppress the sulfuration of metals. In particular, when the polymerizable component is polymerizable component A, the sulfuration-preventing curable composition can form a pressure-sensitive adhesive sheet that can suppress the sulfuration of metals. Furthermore, when the polymerizable component is polymerizable component B, the sulfuration-preventing curable composition can form a film (coating film) that can suppress the sulfuration of metals. This is particularly suitable for suppressing the sulfuration of metal layers formed from metals including silver or copper. Preferably, such metal layers have a mesh structure, for example.

[0082] That is, the metal for which sulfidation is suppressed by the sulfidation-preventing curable composition is silver or copper, and a metal layer having a mesh structure is preferable, and among these, silver is preferable. Examples of the metal layer include copper nanowires and silver nanowires.

[0083] 2. Adhesive sheet The pressure-sensitive adhesive sheet can be obtained by curing the sulfurization-preventing curable composition, and in particular, can be obtained by curing the sulfurization-preventing curable composition containing the polymerizable component A. That is, the pressure-sensitive adhesive sheet contains a cured product of the sulfurization-preventing curable composition, and in particular, contains a cured product of the sulfurization-preventing curable composition containing the polymerizable component A.

[0084] The method for forming the pressure-sensitive adhesive sheet is not particularly limited, and may include, for example, a step of applying the sulfurization-preventing curable composition to a substrate to form a coating film, and a step of irradiating the coating film with active energy rays to cure the coating film and obtain a pressure-sensitive adhesive sheet. The sulfurization-preventing curable composition can be applied using a known coating device. Examples of the coating device include a blade coater, an air knife coater, a roll coater, a bar coater, a gravure coater, a microgravure coater, a rod blade coater, a lip coater, a die coater, and a curtain coater.

[0085] The substrate used for coating is not particularly limited. For example, the sulfur-preventing curable composition can be coated on a release sheet described below. The thickness after coating is also not particularly limited and can be appropriately set depending on the desired thickness. After forming the coating film, the coating film may be subjected to a heat treatment or a drying treatment, if necessary.

[0086] The method of irradiating the coating film with active energy is not particularly limited. For example, ultraviolet light can be applied at an integrated light dose of 100 to 10,000 mJ / cm. 2 It is preferable to set the value to 200 to 5000 mJ / cm 2 It is more preferable to set it so that:

[0087] The cured product formed as described above can be used as the pressure-sensitive adhesive sheet of the present invention. The pressure-sensitive adhesive sheet may consist of only a layer formed of the cured product of the sulfur-preventing curable composition, or may contain other layers in addition to the layer formed of the cured product. The pressure-sensitive adhesive sheet of the present invention preferably has, for example, a single-layer structure.

[0088] The gel fraction of the pressure-sensitive adhesive sheet of the present invention is not particularly limited, and is, for example, 20% or more and 90% or less, preferably 25% or more, more preferably 30% or more, and preferably 85% or less, more preferably 80% or less.

[0089] The gel fraction of the adhesive sheet is a value measured by the following method. First, approximately 0.1 g of adhesive sheet is placed in a sample bottle, 30 ml of ethyl acetate is added, and the mixture is shaken at 40°C for 24 hours. The contents of the sample bottle are then filtered through a 150-mesh stainless steel wire mesh, and the residue on the mesh is dried at 100°C for 1 hour to measure the dry mass (g). The obtained dry mass is then calculated using the following formula: Gel fraction (mass%) = (dry mass / collected mass of adhesive sheet) × 100 Equation 1 Calculate the gel fraction using 1.

[0090] The thickness of the pressure-sensitive adhesive sheet of the present invention can be appropriately set depending on the application, and is, for example, preferably 10 to 1000 μm, more preferably 20 to 500 μm.

[0091] The pressure-sensitive adhesive sheet of the present invention can also be a pressure-sensitive adhesive sheet provided with a substrate such as a release sheet on one or both sides. Examples of release sheets include a release laminate sheet having a release sheet substrate and a release agent layer provided on one side of the release sheet substrate, or a polyolefin film such as a polyethylene film or a polypropylene film as a low-polarity substrate. Paper or a polymer film is used as the release sheet substrate in the release laminate sheet. Examples of release agents that constitute the release agent layer include general-purpose addition-type or condensation-type silicone-based release agents and long-chain alkyl group-containing compounds. Commercially available release laminate sheets may also be used. Examples include a heavy-duty separator film, which is a release-treated polyethylene terephthalate film manufactured by Oji F-Tex Co., Ltd., and a light-duty separator film, which is a release-treated polyethylene terephthalate film manufactured by Oji F-Tex Co., Ltd.

[0092] Since the pressure-sensitive adhesive sheet of the present invention is formed using the sulfidation-preventing curable composition, it can suppress sulfidation of metals. In particular, the pressure-sensitive adhesive sheet of the present invention can be suitably used to prevent sulfidation of a metal layer having a mesh structure, i.e., the pressure-sensitive adhesive sheet of the present invention can be used to attach a metal layer having a mesh structure to another member. The pressure-sensitive adhesive sheet of the present invention is more preferably used to prevent sulfidation of a metal layer having a mesh structure formed from a metal containing silver or copper, and particularly preferably used to prevent sulfidation of a metal layer having a mesh structure formed from a metal containing silver.

[0093] 3. Coating The coating can be obtained by curing the sulfurization-preventing curable composition, particularly by curing the sulfurization-preventing curable composition containing polymerizable component B. That is, the coating contains a cured product of the sulfurization-preventing curable composition, particularly a cured product of the sulfurization-preventing curable composition containing polymerizable component B.

[0094] The method for forming the film is not particularly limited, and for example, methods similar to those for forming known coating films can be widely used. Alternatively, the film can be formed using a method similar to the method for forming the pressure-sensitive adhesive sheet described above. In this case, the member to be coated with the sulfidation-preventing curable composition is directly coated onto the member on which the film is to be formed, thereby forming the film. Therefore, the substrate used for coating to form the film is preferably a metal layer formed of a metal containing silver or copper and having a mesh structure.

[0095] The coating may consist solely of a layer formed from the cured product of the sulfuration-preventing curable composition, or may contain other layers in addition to the layer formed from the cured product. The coating of the present invention preferably has, for example, a single-layer structure.

[0096] The thickness of the coating of the present invention can be appropriately set depending on the application, and is, for example, preferably 0.1 to 20 μm, more preferably 0.5 to 10 μm, and even more preferably 1 to 5 μm.

[0097] The coating of the present invention is formed using the sulfidation-preventing curable composition, and therefore can suppress sulfidation of metals. In particular, the coating can be suitably used to prevent sulfidation of metal layers having a mesh structure formed from a metal containing silver or copper, and is particularly suitable for preventing sulfidation of metal layers having a mesh structure formed from a metal containing silver.

[0098] 4. Display device member having adhesive sheet The pressure-sensitive adhesive sheet formed using the curable composition for preventing sulfuration has excellent sulfuration prevention performance for metals, and can therefore be suitably used, for example, in display device components including touch sensor films.

[0099] In the display device member, the touch sensor film may include a laminate including an adhesive sheet formed using the sulfidation-preventing curable composition and a metal layer having a mesh structure, wherein the adhesive sheet is attached to at least one side of the metal layer, and the metal layer is preferably silver or copper.

[0100] The adhesive sheet is preferably directly attached to the metal layer. The touch sensor film may have the same configuration as a known touch sensor film, for example, as long as it includes the adhesive sheet and the metal layer.

[0101] The display device member includes an adhesive sheet to suppress sulfurization of the metal layer, thereby making it less likely for the touch sensor to deteriorate in sensitivity and malfunction. The configuration of the display device member is not particularly limited, and can be, for example, the same configuration as that of a display device member including a known touch sensor film. The display device member can include, for example, a glass plate, a polarizing plate, etc. As long as the adhesive sheet of the present invention is attached to the metal layer, each component constituting the display device member may be attached with another adhesive sheet, or a component other than the metal layer may be attached with the adhesive sheet of the present invention. The display device member can be suitably applied to various display devices.

[0102] 5. Uses of the coating The film formed using the sulfurization-preventing curable composition has excellent sulfurization-preventing properties for metals, and can therefore be suitably used for, for example, display device components including touch sensor films.

[0103] In the display device member, the touch sensor film may include a laminate including a coating formed using the sulfidation-preventing curable composition and a metal layer having a mesh structure, and in this case, the coating is formed on at least one side of the metal layer, and the metal layer is preferably made of silver or copper.

[0104] The coating is preferably formed directly on the metal layer. The touch sensor film may have the same configuration as a known touch sensor film, as long as it includes the coating and the metal layer.

[0105] The display device member is provided with a coating to suppress sulfurization of the metal layer, thereby making it less likely for the touch sensor to deteriorate in sensitivity and malfunction. The configuration of the display device member is not particularly limited, and can be, for example, the same configuration as a display device member provided with a known touch sensor film. The display device member can include, for example, a glass plate, a polarizing plate, etc. The components constituting the display device member may be bonded together with, for example, a known pressure-sensitive adhesive sheet, or may be bonded together with the pressure-sensitive adhesive sheet of the present invention described above. The display device member can be suitably applied to various display devices.

[0106] In specifying the inventions included in the present disclosure, the components (properties, structures, functions, etc.) described in the embodiments of the present disclosure may be combined in any manner. In other words, the present disclosure includes all subject matter consisting of all combinations of the components that can be combined as described in this specification. [Example]

[0107] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

[0108] The following monofunctional monomers, thiourea compounds, and photopolymerization initiators were prepared for preparing polymerizable component A or polymerizable component B used in each example.

[0109] (monofunctional monomer) 2EHA: 2-Ethylhexyl acrylate ISTA: Isostearyl acrylate ·DMAA: N,N-dimethylacrylamide DEAA: N,N-diethylacrylamide IBXA: Isobornyl acrylate

[0110] (Thiourea compounds having a cyclic structure containing an -NC(=S)-N- bond) 1,3-Trimethylene-2-thiourea

[0111] (Thiourea compounds that do not have a cyclic structure containing an -NC(=S)-N- bond) Diethylthiourea Dibutylthiourea Dilauryl thiourea 1-Phenyl-2-thiourea 1,3-Diphenyl-2-thiourea

[0112] (Photopolymerization initiator) ESACURE ONE (registered trademark, manufactured by IGM Resins BV)

[0113] Example 1 Polymerizable component A (a partial polymer of an acrylic polymer) containing an acrylic polymer and a monofunctional monomer was synthesized according to the blending conditions for preparing the polymerizable component shown in Table 1. Specifically, 100 parts by mass of a monomer mixture consisting of 2EHA, ISTA, DMAA, and IBXA (mass ratio 35:45:10:10) in the blending amounts shown in Table 1 was placed in a flask. 0.05 parts by mass of 1-hydroxycyclohexyl phenyl ketone as an initiator was added to this monomer mixture, and the mixture was heated at an illuminance of 3 mW / cm while introducing nitrogen gas. 2The polymer was partially polymerized by irradiating the polymer with ultraviolet light of 1000 W at 1000 W / m², thereby obtaining a polymerizable component A (syrup) containing an acrylic polymer and a monomer with a conversion rate (polymer fraction) of 31%. The weight average molecular weight Mw of the obtained acrylic polymer measured by GPC in terms of polystyrene was 880,000, and the theoretical Tg was -24°C. The glass transition temperature Tg was a theoretical value calculated using the following FOX formula. 1 / Tg=W1 / Tg1+W2 / Tg2+···+Wn / Tgn··· FOX formula (In the formula, Tg is the glass transition temperature (K: Kelvin) of the acrylic copolymer, W1, W2...Wn are the mass fractions of each monomer that makes up the acrylic copolymer, and Tg1, Tg2...Tgn are the glass transition temperatures of the homopolymers of each monomer.)

[0114] Next, 0.08 parts by mass of ATM-4PL (manufactured by Shin-Nakamura Chemical Co., Ltd.) as a polyfunctional monomer, 0.2 parts by mass of ESACURE ONE as a photopolymerization initiator, and 0.03 parts by mass of 1,3-trimethylene-2-thiourea as a thiourea compound were added to 100 parts by mass of the total mass of polymerizable component A to obtain a curable composition for preventing sulfurization. This curable composition for preventing sulfurization was uniformly applied with an applicator to the surface of a 100 μm thick polyethylene terephthalate film (first release sheet) (manufactured by Oji F-Tex Co., Ltd.: 100RL-07(2)) equipped with a release agent layer treated with a silicone-based release agent, so that the coating film thickness after drying would be 150 μm. A 75 μm thick polyethylene terephthalate film (second release sheet) (Oji F-Tex Co., Ltd.: 75RL-07(L)) with a release agent layer treated with a silicone-based release agent was laminated onto the coated surface, and then a black light was irradiated from the first release sheet side at an illuminance of 4 mW / cm at 365 nm. 2 The cumulative light intensity is 240mJ / cm 2 Then, a high-pressure mercury lamp was used at an illuminance of 100 mW / cm at 365 nm. 2 The illuminance is 1000mJ / cm 2 Then, a metal halide lamp was used to illuminate the sample at an illuminance of 150 mW / cm 2 The cumulative light intensity is 1500mJ / cm2 By irradiating the film so as to obtain a double-sided pressure-sensitive adhesive sheet with a release sheet, the pressure-sensitive adhesive layer was sandwiched between a pair of release sheets with different release strengths, resulting in a first release sheet / pressure-sensitive adhesive layer / second release sheet configuration.

[0115] Example 2 A sulfuration-preventing curable composition and a pressure-sensitive adhesive sheet were obtained in the same manner as in Example 1, except that the amount of 1,3-trimethylene-2-thiourea used was changed to the formulation shown in Table 1.

[0116] (Comparative Examples 1 to 5) A sulfuration-preventing curable composition and an adhesive sheet were obtained in the same manner as in Example 1, except that the type and amount of thiourea compound used were changed to the formulation shown in Table 1.

[0117] [Evaluation method] (Haze of adhesive sheet, b * value) The adhesive sheet with the release sheet was cut into a size of 50 mm x 50 mm, and the light separator was peeled off, and the exposed adhesive layer was attached to a glass plate (S9112, manufactured by Matsunami Glass Co., Ltd.). Next, the heavy separator was peeled off, and a glass plate (S9112, manufactured by Matsunami Glass Co., Ltd.) was attached to the exposed adhesive layer. The autoclave was then placed and treated for 30 minutes under a pressure of 0.5 MPa in an atmosphere of 40°C to obtain a laminate. This laminate was used to measure the initial haze, b * The haze and b values ​​were measured after storing the laminate at 85°C for 10 days. * value, and haze after storage at 60°C and 95% RH for 10 days, b * values ​​were also measured.

[0118] (Haze of the film, b * value) A curable composition for preventing sulfuration was applied to a glass plate (S9112, manufactured by Matsunami Glass Co., Ltd.) to a thickness of 0.1 mm, and a first release sheet was placed on the coated surface. A black light was irradiated from the first release sheet side with an illuminance of 4 mW / cm at 365 nm. 2The cumulative light intensity is 240mJ / cm 2 Then, a high-pressure mercury lamp was used at an illuminance of 100 mW / cm at 365 nm. 2 The illuminance is 1000mJ / cm 2 Then, a metal halide lamp was used to illuminate the sample at an illuminance of 150 mW / cm 2 The cumulative light intensity is 1500mJ / cm 2 The release film was then peeled off to obtain a laminate. This laminate was used to measure the initial haze, b * The haze and b values ​​were measured after storing the laminate at 85°C for 10 days. * value, and haze after storage at 60°C and 95% RH for 10 days, b * values ​​were also measured.

[0119] (Anti-sulfuration performance evaluation; adhesive sheet) A 100 μm thick PET film was coated with silver paste (Dotite D500, manufactured by Fujikura Chemical Industries, Ltd.) to a thickness of 0.1 mm, dried at room temperature for 6 hours, and then cut into a 50 mm x 30 mm piece to produce a PET film substrate with a Dotite D500 coating. Next, a 10 mm square adhesive sheet was cut, the lightweight separator was peeled off, and the sheet was attached to the center of the silver paste on the PET film substrate to produce an evaluation sample. Meanwhile, 5 mg of sulfur (manufactured by Wako Pure Chemical Industries, Ltd.) was placed in a 60 mL mayonnaise bottle, and the 50 mm side of the evaluation sample was placed in the bottle so that it touched the bottom. The mayonnaise bottle was then placed in an oven with the lid on at 95°C for heat treatment. The color change of the adhesive sheet in the evaluation sample was checked every hour from the start of the heat treatment, and the anti-sulfuration performance was evaluated based on the following criteria. <Judgment criteria> Good: No discoloration was observed even after 2 hours had passed since the heat treatment, demonstrating excellent performance in preventing sulfurization of metals. △: Even after 2 hours from the heat treatment, only slight discoloration was observed, and there was no practical problem in terms of the sulfuration prevention performance for metals. ×: Blackening was observed 1 hour after the heat treatment, and the sulfuration prevention performance for metals was extremely poor.

[0120] (Anti-sulfuration performance evaluation; coating) The laminates having the sulfuration prevention coating obtained in the examples were cut into 50 mm wide x 30 mm long pieces so that the sulfuration prevention coating was in the center to prepare evaluation samples. 5 mg of sulfur (manufactured by Wako Pure Chemical Industries, Ltd.) was placed in a 60 mL mayonnaise bottle, and the evaluation sample was placed in the mayonnaise bottle so that the 50 mm side touched the bottom of the mayonnaise bottle. The mayonnaise bottle was placed in an oven with the lid on and heated at 95°C. The color change of the sulfuration prevention coating portion of the evaluation sample was checked every hour from the start of the heating treatment, and the sulfuration prevention performance was evaluated based on the following criteria. <Judgment criteria> ⊚: No discoloration was observed even after 3 hours had passed since the heat treatment, and the performance of preventing sulfurization of metals was extremely excellent. Good: No discoloration was observed even after 2 hours had passed since the heat treatment, demonstrating excellent performance in preventing sulfurization of metals. △: Even after 2 hours from the heat treatment, only slight discoloration was observed, and there was no practical problem in terms of the sulfuration prevention performance for metals. ×: Blackening was observed 1 hour after the heat treatment, and the sulfuration prevention performance for metals was extremely poor.

[0121] (Evaluation method) Table 1 shows the compounding conditions for preparing the sulfurization-preventing curable compositions of each Example and Comparative Example, as well as the evaluation results of the resulting pressure-sensitive adhesive sheets or films and the evaluation results of the sulfurization-preventing performance. In Table 1, blank cells indicate that the corresponding raw material was not used.

[0122] From Table 1, it was found that a pressure-sensitive adhesive sheet obtained from a curable composition for preventing sulfuration containing a specified amount of a specific thiourea compound can inhibit sulfuration of metals.

[0123] [Table 1]

Claims

1. A curable composition used to prevent sulfidation of metals, comprising: Contains at least a thiourea compound and a polymerizable component, The thiourea compound has a cyclic structure, the cyclic structure has a structure containing an —N—C(═S)—N— bond, the polymerizable component is at least one selected from the group consisting of an acrylic polymer and a monofunctional monomer, The sulfurization-preventing curable composition contains the thiourea compound in an amount of 0.01 part by mass or more and 0.1 part by mass or less per 100 parts by mass of the polymerizable component.

2. 2. The sulfuration-preventing curable composition according to claim 1, wherein the metal is silver or copper, and the metal layer has a mesh structure.

3. A pressure-sensitive adhesive sheet comprising a cured product of the curable composition for preventing sulfidation according to claim 1 or 2.

4. A coating comprising a cured product of the sulfuration-preventing curable composition according to claim 1 or 2.

5. A display device member including a touch sensor film, The touch sensor film comprises a laminate including the adhesive sheet according to claim 3 and a metal layer having a mesh structure, the pressure-sensitive adhesive sheet is attached to at least one surface of the metal layer, The metal layer is silver or copper.

6. A display device member including a touch sensor film, The touch sensor film comprises a laminate including the film according to claim 4 and a metal layer having a mesh structure; the coating is formed on at least one surface of the metal layer; The metal layer is silver or copper.

7. A display device comprising the member for a display device according to claim 5 .

8. A display device comprising the member for a display device according to claim 6 .

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