Peeling layer-forming composition and peeling layer

Abstract

To provide a peeling layer-forming composition capable of forming a peeling layer with a superior balance between adhesion and peelability.SOLUTION: A peeling layer-forming composition contains a polyamic acid, a silane coupling agent represented by a formula (E), and an organic solvent. (In the formula (E), R2 represents a group represented by a formula (E-1) or a formula (E-2)) (where, R11-R13 independently represent H or an organic group, and Y represents O or S).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a flexible electronic device comprising a release layer-forming composition, a release layer, and a resin substrate. [Background technology]

[0002] In recent years, electronic devices are required to have functions such as flexibility and to be thin and lightweight, which requires the use of lightweight flexible plastic substrates instead of conventional heavy, fragile, and inflexible glass substrates.

[0003] In particular, new generation displays require the development of active matrix full color TFT (thin film transistor) display panels using lightweight flexible plastic substrates (hereafter referred to as resin substrates). The technology related to these new generation displays is expected to be applicable to various fields such as flexible displays, flexible smartphones, and mirror displays.

[0004] Therefore, various methods for manufacturing electronic devices using resin films as substrates have been studied, and for new generation displays, studies are being conducted on manufacturing processes that can be used with existing TFT equipment. For example, Patent Documents 1, 2, and 3 disclose a method in which an amorphous silicon thin film layer is formed on a glass substrate, a plastic substrate is formed on the thin film layer, and then a laser is irradiated from the glass surface side to peel off the plastic substrate from the glass substrate by hydrogen gas generated by crystallization of the amorphous silicon.

[0005] Furthermore, Patent Document 4 discloses a method for completing a liquid crystal display device by attaching a peelable layer (referred to as a "transferable layer" in Patent Document 4) to a plastic film using the techniques disclosed in Patent Documents 1 to 3.

[0006] However, the methods disclosed in Patent Documents 1 to 4, and especially the method disclosed in Patent Document 4, have problems in that it is essential to use a highly light-transmitting substrate to transmit the laser light, that it is necessary to irradiate the laser light with a relatively large energy sufficient to pass through the substrate and further release hydrogen contained in the amorphous silicon, and that the layer to be peeled off may be damaged by the irradiation of the laser light. Moreover, when the peeling layer has a large area, it takes a long time for the laser treatment, making it difficult to increase the productivity of device fabrication.

[0007] In view of this, a release layer-forming composition containing a specific polyamic acid and an organic solvent has been proposed as a composition for forming a release layer that can be peeled off without damaging the resin substrate of a flexible electronic device formed thereon and that provides a release layer whose releasability does not change even after heating treatment at relatively high temperatures in a TFT process or the like (e.g., Patent Document 5). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 10-125929 [Patent Document 2] Japanese Patent Application Publication No. 10-125931 [Patent Document 3] International Publication No. 2005 / 050754 [Patent Document 4] Japanese Patent Application Publication No. 10-125930 [Patent Document 5] International Publication No. 2017 / 204178 Summary of the Invention [Problem to be solved by the invention]

[0009] The release layer is required to have both adhesion that prevents easy peeling until the time of peeling and releasability that allows easy peeling when peeling is required. However, when the substrate is a substrate having low adhesion, such as a glass substrate, it is difficult to achieve both adhesion and peelability.

[0010] The present invention has been made in consideration of the above circumstances, and aims to provide a release layer-forming composition capable of forming a release layer that can achieve both adhesion and releasability, a release layer formed using the release layer-forming composition, and a method for manufacturing a flexible electronic device having a resin substrate using the release layer. [Means for solving the problem]

[0011] As a result of extensive research to achieve the above-mentioned object, the inventors discovered that by adding a specific silane coupling agent to a release layer-forming composition containing polyamic acid, a release layer that can achieve both adhesion and releasability can be obtained, and thus completed the present invention.

[0012] That is, the present invention includes the following. [1] A composition for forming a release layer, comprising a polyamic acid, a silane coupling agent represented by the following formula (E), and an organic solvent: [ka] (In formula (E), X 1 ~X 3 each independently represents an alkoxy group, an aralkyloxy group, an acyloxy group, a halogen atom, or an alkyl group (provided that X 1 ~X 3 Except when all of the groups represent alkyl groups. R 1 represents an alkylene group having 1 to 6 carbon atoms. R 2 represents a group represented by the following formula (E-1) or formula (E-2). [ka] (In formula (E-1), R 11 ~R 13 each independently represents a hydrogen atom or an organic group having 1 to 6 carbon atoms (provided that R11 ~R 13 At least one of represents a hydrogen atom. Y represents an oxygen atom or a sulfur atom. In formula (E-1) and formula (E-2), * represents a bond. [2] The polyamic acid is a reaction product of raw material components including a tetracarboxylic dianhydride and a diamine component, the tetracarboxylic dianhydride comprises an aromatic tetracarboxylic dianhydride, The diamine component comprises an aromatic diamine. The composition for forming a release layer according to [1]. [3] The composition for forming a release layer according to [2], wherein the aromatic tetracarboxylic dianhydride is represented by the following formula (1-1) or formula (1-2): [ka] (In formula (1-1), Ar 1 represents a tetravalent group obtained by removing two pairs of adjacent hydrogen atoms from a benzene ring which may have a substituent, or a tetravalent group obtained by removing two pairs of adjacent hydrogen atoms from a naphthalene ring which may have a substituent. In formula (1-2), X 1 represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), or a group represented by the following formula (1-2-1). R a each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. Each n independently represents an integer of 0 to 3. One (R a ) n When n is 2 or more, two or more R a may be the same or different.) [ka] (In formula (1-2-1), Y 1 and Y2 each independently represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, or -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). Ar 2 represents a divalent group obtained by removing two hydrogen atoms from a phenylene group which may have a substituent, or a biphenyl group which may have a substituent. * represents a bond.) [4] The composition for forming a release layer according to [2] or [3], wherein the aromatic diamine is represented by the following formula (2-1) or formula (2-2): [ka] (In formula (2-1), X 11 represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), or a group represented by the following formula (2-1-1). R b each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. Each m independently represents an integer of 0 to 4. One (R b ) m In the above, when m is 2 or more, two or more R b may be the same or different. In formula (2-2), X 12 represents an -NH- group, an -O- group, or an -S- group. R c each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. p1 represents an integer of 0 to 3. p2 represents an integer of 0 to 4. (R c ) p1 In the above, when p1 is 2 or more, two or more R c may be the same or different. (R c ) p2 In this case, when p2 is 2 or more, two or more R c may be the same or different.) [ka] (In formula (2-1-1), Y 11 and Y 12 each independently represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, or -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). Z 11 represents a divalent hydrocarbon group having 1 to 20 carbon atoms. * represents a bond.) [5] The aromatic diamine is represented by the formula (2-1), X in the formula (2-1) 11 represents a group represented by formula (2-1-1); The composition for forming a release layer according to [4]. [6] The composition for forming a release layer according to any one of [2] to [5], wherein the raw material components further contain a dicarboxylic acid anhydride. [7] The composition for forming a release layer according to any one of [1] to [6], wherein the content of the silane coupling agent is 0.01% by mass to 15% by mass with respect to the polyamic acid. [8] A release layer formed from the composition for forming a release layer according to any one of [1] to [7]. [9] A method for producing a flexible electronic device having a resin substrate, using the release layer described in [8]. Effect of the Invention

[0013] According to the present invention, it is possible to provide a release layer forming composition capable of forming a release layer that can achieve both adhesion and releasability, a release layer formed using the release layer forming composition, and a method for manufacturing a flexible electronic device having a resin substrate using the release layer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] (Composition for forming release layer) The release layer-forming composition of the present invention contains a polyamic acid, a silane coupling agent represented by formula (E), and an organic solvent. The release layer-forming composition may contain other components.

[0015] <Polyamic acid> The polyamic acid is, for example, a reaction product of raw material components including a tetracarboxylic dianhydride and a diamine component. The raw material components may contain other raw material components such as a dicarboxylic acid anhydride and a monoamine component.

[0016] <<Tetracarboxylic acid dianhydride>> The tetracarboxylic dianhydride is not particularly limited, but preferably contains an aromatic tetracarboxylic dianhydride, since a release layer having excellent heat resistance can be obtained. Here, the aromatic tetracarboxylic dianhydride is a compound in which a total of two acid anhydride groups are bonded to the same or different aromatic rings. The aromatic ring may be an aromatic hydrocarbon ring or an aromatic heterocycle.

[0017] The aromatic tetracarboxylic dianhydride is not particularly limited, but is preferably represented by the following formula (1-1) or formula (1-2) in that a release layer having superior heat resistance can be obtained. [ka] (In formula (1-1), Ar 1 represents a tetravalent group obtained by removing two pairs of adjacent hydrogen atoms from a benzene ring which may have a substituent, or a tetravalent group obtained by removing two pairs of adjacent hydrogen atoms from a naphthalene ring which may have a substituent. In formula (1-2), X 1represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), or a group represented by the following formula (1-2-1). R a each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. Each n independently represents an integer of 0 to 3. One (R a ) n When n is 2 or more, two or more R a may be the same or different.) [ka] (In formula (1-2-1), Y 1 and Y 2 each independently represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, or -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). Ar 2 represents a divalent group obtained by removing two hydrogen atoms from a phenylene group which may have a substituent, or a biphenyl group which may have a substituent. * represents a bond.)

[0018] In this specification, examples of halogen atoms include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

[0019] In this specification, examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.

[0020] Ar in formula (1-1) 1The substituents which the benzene ring and the naphthalene ring in the formula (I) may have are not particularly limited, but examples thereof include a halogen atom, an alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms.

[0021] Ar in formula (1-1) 1 Examples of the aryl group include the following tetravalent groups: [ka] (In the formula, * represents a bond.)

[0022] In the formula (1-2), n is an integer of 0 to 3, preferably an integer of 0 to 2, and more preferably 0.

[0023] Ar in formula (1-2-1) 2 In the above formula, the substituent that the phenylene group and the divalent group obtained by removing two hydrogen atoms from biphenyl may have is not particularly limited, but examples thereof include a halogen atom, an alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms.

[0024] X in formula (1-2) 1 Examples of the group include the following groups. [ka] (In the formula, * represents a bond.)

[0025] Specific examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, naphthalene-1,2,3,4-tetracarboxylic dianhydride, naphthalene-1,2,5,6-tetracarboxylic dianhydride, naphthalene-1,2,6,7-tetracarboxylic dianhydride, naphthalene-1,2,7,8-tetracarboxylic dianhydride, and naphthalene-2,3,5,6-tetracarboxylic dianhydride. Naphthalene-2,3,6,7-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, biphenyl-2,2',3,3'-tetracarboxylic dianhydride, biphenyl-2,3,3',4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, anthracene-1,2,3,4-tetracarboxylic dianhydride, anthracene-1,2,5,6-tetracarboxylic dianhydride, a Anthracene-1,2,6,7-tetracarboxylic dianhydride, Anthracene-1,2,7,8-tetracarboxylic dianhydride, Anthracene-2,3,6,7-tetracarboxylic dianhydride, Phenanthrene-1,2,3,4-tetracarboxylic dianhydride, Phenanthrene-1,2,5,6-tetracarboxylic dianhydride, Phenanthrene-1,2,6,7-tetracarboxylic dianhydride, Phenanthrene-1,2,7,8-tetracarboxylic dianhydride Examples of the dianhydride include, but are not limited to, phenanthrene-1,2,9,10-tetracarboxylic dianhydride, phenanthrene-2,3,5,6-tetracarboxylic dianhydride, phenanthrene-2,3,6,7-tetracarboxylic dianhydride, phenanthrene-2,3,9,10-tetracarboxylic dianhydride, phenanthrene-3,4,5,6-tetracarboxylic dianhydride, and phenanthrene-3,4,9,10-tetracarboxylic dianhydride. These may be used alone or in combination of two or more.

[0026] The structural formula of an example of an aromatic tetracarboxylic dianhydride is shown below. [ka] [ka]

[0027] The tetracarboxylic dianhydride may contain a tetracarboxylic dianhydride other than an aromatic tetracarboxylic dianhydride. Examples of such a tetracarboxylic dianhydride include 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic dianhydride, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene tetracarboxylic dianhydride, and 1,2,4,5-cyclohexane tetracarboxylic dianhydride. Examples of the compound include alicyclic tetracarboxylic dianhydrides such as 1,2-ene-1,2-dicarboxylic anhydride, 2,3,5-tricarboxy-2-cyclopentane acetic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, and 3,5,6-tricarboxy-2-norbornane acetic dianhydride, and aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butane tetracarboxylic dianhydride.

[0028] The molar ratio of the aromatic tetracarboxylic dianhydride in the tetracarboxylic dianhydride is not particularly limited, but is preferably 50 mol % or more, more preferably 70 mol % or more, and particularly preferably 90 mol % or more. The molar ratio of the aromatic tetracarboxylic dianhydride in the tetracarboxylic dianhydride may be 100 mol % or less, or may be less than 100 mol %.

[0029] <<Diamine component>> The diamine component is not particularly limited, but preferably contains an aromatic diamine, since a release layer having excellent heat resistance can be obtained. Here, the aromatic diamine is a compound in which a total of two amino groups (-NH2) are bonded to the same or different aromatic rings. The aromatic ring may be an aromatic hydrocarbon ring or an aromatic heterocycle.

[0030] The aromatic diamine is not particularly limited, but is preferably represented by the following formula (2-1) or (2-2) in that a release layer having superior heat resistance can be obtained. [ka] (In formula (2-1), X 11 represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), or a group represented by the following formula (2-1-1). R b each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. Each m independently represents an integer of 0 to 4. One (R b ) m In the above, when m is 2 or more, two or more R b may be the same or different. In formula (2-2), X 12 represents an -NH- group, an -O- group, or an -S- group. R c each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. p1 represents an integer of 0 to 3. p2 represents an integer of 0 to 4. (R c ) p1 In the above, when p1 is 2 or more, two or more R c may be the same or different. (R c ) p2 In this case, when p2 is 2 or more, two or more R c may be the same or different.) [ka] (In formula (1-2-1), Y 1 and Y 2 each independently represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, or -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). Ar 2 represents a divalent group obtained by removing two hydrogen atoms from a phenylene group which may have a substituent, or a biphenyl group which may have a substituent. * represents a bond.)

[0031] Z in formula (2-1-1) 11 Examples of the divalent hydrocarbon group having 1 to 20 carbon atoms include alkylene groups having 1 to 20 carbon atoms. The alkylene group having 1 to 20 carbon atoms may be either linear or branched, and specific examples thereof include, but are not limited to, methylene, ethylene, propylene, trimethylene, tetramethylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, tridecylene, tetradecylene, pentadecylene, hexadecylene, heptadecylene, octadecylene, nonadecylene, and eicosanylene. In the present invention, an alkylene group having 2 to 6 carbon atoms is preferred, and a linear alkylene group having 2 to 6 carbon atoms is more preferred.

[0032] Z in formula (2-1-1) 11 The divalent hydrocarbon group having 1 to 20 carbon atoms may be, for example, a divalent hydrocarbon group having a fluorene skeleton.

[0033] In formula (2-1), an amino group (-NH2) and X are bonded to one benzene ring. 11 In order to preferably obtain the effects of the present invention, the position is preferably para.

[0034] In formula (2-1), X 11preferably represents a group represented by formula (2-1-1) in that a release layer can be formed that can be peeled off without damaging the resin substrate of a flexible electronic device. In formula (2-1-1), Y 11 and Y 12 preferably represents an ether bond. In formula (2-1-1), Z 11 preferably represents an alkylene group having 1 to 20 carbon atoms, and more preferably represents an alkylene group having 2 to 6 carbon atoms.

[0035] In the formula (2-1), m is an integer of 0 to 4, preferably an integer of 0 to 2, and more preferably 0. In the formula (2-2), p1 is an integer of 0 to 3, preferably an integer of 0 to 2, and more preferably 0. In the formula (2-2), p2 is an integer of 0 to 4, preferably an integer of 0 to 2, and more preferably 0.

[0036] Examples of aromatic diamines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2-methyl-1,4-phenylenediamine, 5-methyl-1,3-phenylenediamine, 4-methyl-1,3-phenylenediamine, 2-(trifluoromethyl)-1,4-phenylenediamine, 2-(trifluoromethyl)-1,3-phenylenediamine, 4-(trifluoromethyl)-1,3-phenylenediamine, benzidine, 2,2'-dimethylbenzidine, 3,3' -dimethylbenzidine, 2,3'-dimethylbenzidine, 2,2'-bis(trifluoromethyl)benzidine, 3,3'-bis(trifluoromethyl)benzidine, 2,3'-bis(trifluoromethyl)benzidine, 4,4'-diaminophenyl ether, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-diaminobenzanilide, 5-amino-2-(3-aminophenyl)-1H-benzimidazole, 9,9-bis(4-aminophenyl)fluorene, and the like.

[0037] The structural formula of one example of an aromatic diamine is shown below. [ka] [ka] [ka] [ka]

[0038] The molar ratio of the aromatic diamine in the diamine component is not particularly limited, but is preferably 50 mol % or more, more preferably 70 mol % or more, and particularly preferably 90 mol % or more. The molar proportion of the aromatic diamine in the diamine component may be 100 mol % or less, or may be less than 100 mol %.

[0039] <<Dicarboxylic acid anhydride>> The dicarboxylic acid anhydride is not particularly limited, but preferably contains an aromatic dicarboxylic acid anhydride, since a release layer having excellent heat resistance can be obtained. Here, the aromatic dicarboxylic acid anhydride is a compound in which one acid anhydride group is bonded to the same or different aromatic rings. The aromatic ring may be an aromatic hydrocarbon ring or an aromatic heterocycle.

[0040] The aromatic dicarboxylic acid anhydride is preferably represented by the following formula (E1-1), since a release layer having superior heat resistance can be obtained. [ka] (In formula (E1-1), R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms.

[0041] Specific examples of aromatic dicarboxylic anhydrides include phthalic anhydride, 2,3-naphthalenedicarboxylic anhydride, and 1,8-naphthalenedicarboxylic anhydride, etc. Among these, phthalic anhydride is particularly suitable in the present invention in consideration of safety, ease of handling, reactivity, etc.

[0042] The molar ratio of aromatic dicarboxylic anhydride in dicarboxylic anhydride is not particularly limited, but is preferably 50 mol % or more, more preferably 70 mol % or more, and particularly preferably 90 mol % or more. The molar ratio of the aromatic dicarboxylic anhydride in the dicarboxylic anhydride may be 100 mol % or less, or may be less than 100 mol %.

[0043] <<Monoamine components>> The monoamine component is not particularly limited, but preferably contains a monoamine having a ring structure, since a release layer having excellent heat resistance can be obtained. The ring structure may be a non-aromatic ring or an aromatic ring. The number of members in the ring structure is not particularly limited, and examples include 5- to 7-membered rings. The ring structure may be a monocyclic or polycyclic ring. Examples of the non-aromatic ring include an aliphatic hydrocarbon ring. The aromatic ring may be an aromatic hydrocarbon ring or an aromatic heterocycle.

[0044] The monoamine component is preferably represented by the following formula (E2-1) or formula (E2-2), since a release layer having superior heat resistance can be obtained. [ka] (In formula (E2-1) and formula (E2-2), R 1 ~R 5 R each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a halogen atom. 1 ~R5 Adjacent two of may be joined together to form a ring structure. R 6 represents a single bond or an alkylene group having 1 to 4 carbon atoms.

[0045] Examples of the monoamine component include aniline, 1-naphthylamine, 2-naphthylamine, 1-aminoanthracene, 2-aminoanthracene, 9-aminoanthracene, 9-aminophenanthracene, 2-aminobiphenyl, 3-aminobiphenyl, and 4-aminobiphenyl.

[0046] The structural formula of an example of the monoamine represented by formula (E2-1) is shown below. [ka]

[0047] The structural formula of an example of the monoamine represented by formula (E2-2) is shown below. [ka]

[0048] The molar ratio of monoamines having a ring structure in the monoamine component is not particularly limited, but is preferably 50 mol % or more, more preferably 70 mol % or more, and particularly preferably 90 mol % or more. The molar proportion of monoamines having a ring structure in the monoamine component may be 100 mol % or less, or may be less than 100 mol %.

[0049] The method for producing the polyamic acid may be, for example, the following embodiment (1). (1): A method for producing a polyamic acid by adding a diamine component and an organic solvent to a reaction vessel, and then adding a tetracarboxylic dianhydride to the reaction vessel and carrying out a reaction.

[0050] When the raw material component contains a dicarboxylic anhydride or a monoamine component, the method for producing a polyamic acid may be, for example, the following embodiment (2). (2) A method for producing a polyamic acid by adding a diamine component and an organic solvent to a reaction vessel, then adding a tetracarboxylic dianhydride to the reaction vessel and carrying out a reaction, and then adding a dicarboxylic anhydride or a monoamine component to the reaction vessel and carrying out a reaction.

[0051] The ratio of the amounts of the tetracarboxylic dianhydride (M1) and the diamine component (M2) used can be appropriately set in consideration of the molecular weight of the desired polyamic acid, the ratio of the monomer units, and the like, and the molar ratio (M1:M2) is, for example, 100:120 to 120:100.

[0052] The organic solvent used in the above-mentioned reaction is not particularly limited as long as it does not adversely affect the reaction, and specific examples thereof include m-cresol, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, 3-methoxy-N,N-dimethylpropylamide, 3-ethoxy-N,N-dimethylpropylamide, 3-propoxy-N,N-dimethylpropylamide, 3-isopropoxy-N,N-dimethylpropylamide, 3-butoxy-N,N-dimethylpropylamide, 3-sec-butoxy-N,N-dimethylpropylamide, 3-tert-butoxy-N,N-dimethylpropylamide, γ-butyrolactone, etc. The organic solvent may be used alone or in combination of two or more kinds.

[0053] In particular, the organic solvent used in the reaction preferably contains at least one selected from the group consisting of amides represented by the following formula (S1), amides represented by the following formula (S2), and amides represented by the following formula (S3), since the organic solvent dissolves the raw materials (diamine component, tetracarboxylic dianhydride, dicarboxylic anhydride, monoamine component) and the product (polyamic acid) well. [ka] (In formulas (S1) to (S3), R 51 , and R 53 each independently represents an alkyl group having 1 to 10 carbon atoms; R 54 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R 52 represents an alkylene group having 1 to 5 carbon atoms.

[0054] Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a s-butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, etc. Among these, an alkyl group having 1 to 3 carbon atoms is preferred, and an alkyl group having 1 or 2 carbon atoms is more preferred.

[0055] Examples of the alkylene group having 1 to 5 carbon atoms include a methylene group, a 1,2-ethylene group, a 1,3-propylene group, a 1,4-butylene group, a 1,5-pentylene group, etc. Among these, a methylene group, a 1,2-ethylene group, and a 1,3-propylene group are preferred, and a methylene group and a 1,2-ethylene group are more preferred.

[0056] The reaction temperature may be appropriately set within the range from the melting point to the boiling point of the solvent used, and is usually about 0 to 100°C. In order to prevent imidization of the resulting polyamic acid and maintain a high content of polyamic acid units, the reaction temperature is preferably about 0 to 70°C, more preferably about 0 to 60°C, and even more preferably about 0 to 50°C. The reaction time cannot be generally defined since it depends on the reaction temperature and the reactivity of the raw materials, but it is usually about 1 to 100 hours.

[0057] By the method described above, a reaction solution containing a polyamic acid can be obtained.

[0058] The weight average molecular weight of the polyamic acid is not particularly limited, but is preferably 3,000 or more, more preferably 5,000 or more, and even more preferably 10,000 or more. On the other hand, the upper limit of the weight average molecular weight of the polyamic acid is usually 2,000,000. However, in consideration of preventing the viscosity of the composition for forming the release layer from becoming excessively high and of reproducibly obtaining a highly flexible resin thin film, the weight average molecular weight of the polyamic acid is preferably 1,000,000 or less, and more preferably 200,000 or less.

[0059] The concentration of the polyamic acid relative to the total mass of the composition for forming the release layer is appropriately set taking into consideration the thickness of the thin film (release layer) to be produced and the viscosity of the composition, but is usually about 0.5 to 30 mass %, preferably about 2 to 25 mass %.

[0060] <<Silane coupling agents>> The silane coupling agent is represented by the following formula (E). [ka] (In formula (E), X 1 ~X 3 each independently represents an alkoxy group, an aralkyloxy group, an acyloxy group, a halogen atom, or an alkyl group (provided that X 1 ~X 3 Except when all of the groups represent alkyl groups. R 1 represents an alkylene group having 1 to 6 carbon atoms. R 2 represents a group represented by the following formula (E-1) or formula (E-2). [ka] (In formula (E-1), R 11 ~R 13 each independently represents a hydrogen atom or an organic group having 1 to 6 carbon atoms (provided that R 11 ~R 13 At least one of represents a hydrogen atom. Y represents an oxygen atom or a sulfur atom. In formula (E-1) and formula (E-2), * represents a bond.

[0061] X in formula (E) 1 ~X 3 In the above, examples of the alkoxy group include alkoxy groups having 1 to 10 carbon atoms. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, an i-butoxy group, an s-butoxy group, a t-butoxy group, an n-pentyloxy group, and a 1-methyl-n-butoxy group. X in formula (E) 1 ~X 3 The number of carbon atoms in the aralkyloxy group is not particularly limited, but can be, for example, 40 or less, preferably 30 or less, and more preferably 20 or less. Specific examples of the aralkyloxy group include a phenylmethyloxy group (benzyloxy group), a 2-phenylethyleneoxy group, a 3-phenyl n-propyloxy group, a 4-phenyl n-butyloxy group, a 5-phenyl n-pentyloxy group, a 6-phenyl n-hexyloxy group, a 7-phenyl n-heptyloxy group, an 8-phenyl n-octyloxy group, a 9-phenyl n-nonyloxy group, and a 10-phenyl n-decyloxy group. The acyloxy group is a monovalent group derived by removing a hydrogen atom from a carboxyl group (-COOH) of a carboxylic acid compound, and typical examples include an alkylcarbonyloxy group, an arylcarbonyloxy group, or an aralkylcarbonyloxy group, which are derived by removing a hydrogen atom from the carboxyl group of an alkylcarboxylic acid, an arylcarboxylic acid, or an aralkylcarboxylic acid. X in formula (E) 1 ~X 3Examples of the acyloxy group in the formula (I) include acyloxy groups having 2 to 20 carbon atoms. Examples of the acyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, an n-propylcarbonyloxy group, an i-propylcarbonyloxy group, an n-butylcarbonyloxy group, an i-butylcarbonyloxy group, an s-butylcarbonyloxy group, a t-butylcarbonyloxy group, an n-pentylcarbonyloxy group, a 1-methyl-n-butylcarbonyloxy group, a 2-methyl-n-butylcarbonyloxy group, a 3-methyl-n-butylcarbonyloxy group, and a 1,1-dimethyl-n-propylcarbonyloxy group. X in formula (E) 1 ~X 3 Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. X in formula (E) 1 ~X 3 In the above formula, examples of the alkyl group include alkyl groups having 1 to 4 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, and a t-butyl group. X in formula (E) 1 ~X 3 may have zero, one, or two alkyl groups.

[0062] X in formula (E) 1 ~X 3 As the alkoxy group, an alkoxy group having 1 to 3 carbon atoms is preferable, and a methoxy group or an ethoxy group is particularly preferable.

[0063] R in formula (E) 1Examples of the alkylene group having 1 to 6 carbon atoms in the formula (I) include a methylene group, an ethylene group, a 1,3-propylene group, a 1-methylethylene group, a 1,4-butylene group, a 1-ethylethylene group, a 1-methylpropylene group, a 2-methylpropylene group, a 1,5-pentylene group, a 1-methylbutylene group, a 2-methylbutylene group, a 1,1-dimethylpropylene group, a 1,2-dimethylpropylene group, a 1-ethylpropylene group, a 2-ethylpropylene group, a 1,6-hexylene group, and a 1,4-cyclohexylene group. Among these, alkylene groups having 1 to 3 carbon atoms are preferred.

[0064] In formula (E-1), R 11 ~R 13 The organic group having 1 to 6 carbon atoms in is not particularly limited and may be a hydrocarbon group or an organic group having a hetero atom. Examples of the hetero atom include an oxygen atom and a nitrogen atom. Examples of the organic group having 1 to 6 carbon atoms include an alkyl group having 1 to 6 carbon atoms, a phenyl group, and a pyridyl group. R 11 ~R 13 At least one represents a hydrogen atom, but R 11 ~R 13 are preferably all hydrogen atoms.

[0065] Examples of the silane coupling agent include the following compounds: [ka] In the formula, X 1 ~X 3 each independently represents a methoxy group or an ethoxy group.

[0066] From the viewpoint of more suitably obtaining the effects of the present invention, the content of the silane coupling agent in the composition for forming the release layer is preferably 0.01% by mass to 15% by mass, more preferably 0.05% by mass to 10% by mass, and particularly preferably 0.1% by mass to 8% by mass, relative to the polyamic acid.

[0067] <Organic solvent> In the present invention, the reaction solution is usually filtered, and the filtrate can be used as it is, or the solution obtained by diluting or concentrating the filtrate can be used as the composition for forming a peeling layer of the present invention. By doing so, not only can the inclusion of impurities that may cause deterioration of the adhesion, peelability, etc. of the obtained peeling layer be reduced, but also the composition for forming a peeling layer can be efficiently obtained. The solvent used for dilution or concentration is not particularly limited, and examples thereof include the same as the specific examples of the reaction solvent for the above reaction, which may be used alone or in combination of two or more kinds.

[0068] Among the above specific examples, in consideration of obtaining a highly flat resin thin film with good reproducibility, the following solvents are preferred: N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethyl-2-pyrrolidone, γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cycloheptane, cyclohexane, diethylene glycol ethyl methyl ether, and ethylene glycol.

[0069] <Other ingredients> The other components are not particularly limited, and examples thereof include a crosslinking agent (hereinafter also referred to as a crosslinkable compound).

[0070] <<Crosslinkable compound>> Examples of crosslinkable compounds include, but are not limited to, compounds containing two or more epoxy groups, melamine derivatives, benzoguanamine derivatives, and glycolurils having a group in which the hydrogen atom of an amino group is substituted with a methylol group, an alkoxymethyl group, or both.

[0071] Specific examples of the crosslinkable compound are listed below, but the invention is not limited thereto. Examples of the compound containing two or more epoxy groups include the following compounds. Epolead GT-401, Epolead GT-403, Epolead GT-301, Epolead GT-302, Celloxide 2021, Celloxide 3000 (all manufactured by Daicel Corporation), and other epoxy compounds having a cyclohexene structure; Bisphenol A type epoxy compounds such as Epicoat 1001, Epicoat 1002, Epicoat 1003, Epicoat 1004, Epicoat 1007, Epicoat 1009, Epicoat 1010, and Epicoat 828 (all manufactured by Japan Epoxy Resins Co., Ltd. (currently manufactured by Mitsubishi Chemical Corporation, jER (registered trademark) series)); Bisphenol F type epoxy compounds such as Epicoat 807 (manufactured by Japan Epoxy Resins Co., Ltd. (now Mitsubishi Chemical Corporation)); Phenol novolac epoxy compounds such as Epicoat 152, Epicoat 154 (both manufactured by Japan Epoxy Resins Co., Ltd. (currently manufactured by Mitsubishi Chemical Corporation, jER (registered trademark) series)), EPPN201, EPPN202 (both manufactured by Nippon Kayaku Co., Ltd.); Cresol novolac epoxy compounds such as ECON-102, ECON-103S, ECON-104S, ECON-1020, ECON-1025, and ECON-1027 (all manufactured by Nippon Kayaku Co., Ltd.), and Epicoat 180S75 (manufactured by Japan Epoxy Resins Co., Ltd. (currently manufactured by Mitsubishi Chemical Corporation, jER (registered trademark) series)); Naphthalene-type epoxy compounds such as V8000-C7 (manufactured by DIC Corporation); Alicyclic epoxy compounds such as Denacol EX-252 (manufactured by Nagase ChemteX Corporation), CY175, CY1770, CY179, Araldite CY-182, Araldite CY-192, Araldite CY-184 (all manufactured by BASF), Epiclon 200, Epiclon 400 (all manufactured by DIC Corporation), Epicoat 871, Epicoat 872 (all manufactured by Japan Epoxy Resins Co., Ltd. (currently manufactured by Mitsubishi Chemical Corporation, jER (registered trademark) series)), ED-5661, ED-5662 (all manufactured by Celanese Coatings Co., Ltd.); Aliphatic polyglycidyl ether compounds such as Denacol EX-611, Denacol EX-612, Denacol EX-614, Denacol EX-622, Denacol EX-411, Denacol EX-512, Denacol EX-522, Denacol EX-421, Denacol EX-313, Denacol EX-314, and Denacol EX-312 (all manufactured by Nagase ChemteX Corporation).

[0072] Examples of melamine derivatives, benzoguanamine derivatives, or glycolurils in which the hydrogen atom of an amino group has been substituted with a methylol group, an alkoxymethyl group, or both include the following compounds. MX-750, which has an average of 3.7 methoxymethyl groups substituted per triazine ring, and MW-30, which has an average of 5.8 methoxymethyl groups substituted per triazine ring (both manufactured by Sanwa Chemical Co., Ltd.); Methoxymethylated melamines such as Cymel 300, Cymel 301, Cymel 303, Cymel 350, Cymel 370, Cymel 771, Cymel 325, Cymel 327, Cymel 703, and Cymel 712 (all manufactured by Mitsui Cyanamid Co., Ltd. (currently Nippon Cytec Industries Co., Ltd.)); Methoxymethylated butoxymethylated melamines such as Cymel 235, Cymel 236, Cymel 238, Cymel 212, Cymel 253, and Cymel 254 (all manufactured by Mitsui Cyanamid Co., Ltd. (currently Nippon Cytec Industries Co., Ltd.)); Butoxymethyl melamine such as Cymel 506 and Cymel 508 (both manufactured by Mitsui Cyanamid Co., Ltd. (currently Nippon Cytec Industries Co., Ltd.)); Carboxylic acid-containing methoxymethylated isobutoxymethylated melamine such as Cymel 1141 (manufactured by Mitsui Cyanamid Co., Ltd. (now Nippon Cytec Industries Co., Ltd.)); Methoxymethylated and ethoxymethylated benzoguanamines such as Cymel 1123 (manufactured by Mitsui Cyanamid Co., Ltd. (now Nippon Cytec Industries Co., Ltd.)); Methoxymethylated butoxymethylated benzoguanamines such as Cymel 1123-10 (manufactured by Mitsui Cyanamid Co., Ltd. (now Nippon Cytec Industries Co., Ltd.)); Butoxymethylated benzoguanamines such as Cymel 1128 (manufactured by Mitsui Cyanamid Co., Ltd. (now Nippon Cytec Industries Co., Ltd.)); Carboxy group-containing methoxymethylated and ethoxymethylated benzoguanamines such as Cymel 1125-80 (manufactured by Mitsui Cyanamid Co., Ltd. (currently Nippon Cytec Industries Co., Ltd.)); Butoxymethylated glycoluril such as Cymel 1170 (manufactured by Mitsui Cyanamid Co., Ltd. (now Nippon Cytec Industries Co., Ltd.)); Methylol glycoluril such as Cymel 1172 (manufactured by Mitsui Cyanamid Co., Ltd. (now Nippon Cytec Industries Co., Ltd.))

[0073] The viscosity of the composition for forming the release layer is appropriately set taking into consideration the thickness of the thin film to be produced, and when the objective is to obtain a resin thin film having a thickness of about 0.05 to 5 μm with good reproducibility, the viscosity is usually about 3 to 10,000 mPa·s at 25°C, preferably about 5 to 1,000 mPa·s, and more preferably about 8 to 200 mPa·s. Here, the viscosity can be measured using a commercially available viscometer for measuring the viscosity of liquids, for example, by referring to the procedure described in JIS K7117-2, under the condition of a composition temperature of 25°C. Preferably, a cone-plate type (corn-plate type) rotational viscometer is used as the viscometer, and preferably, the same type of viscometer is used with a standard cone rotor of 1°34'×R24, and the composition temperature can be measured under the condition of a composition temperature of 25°C. An example of such a rotational viscometer is TVE-25H manufactured by Toki Sangyo Co., Ltd.

[0074] (Release layer) The release layer of the present invention is formed from the release layer-forming composition of the present invention.

[0075] For example, a thin film (release layer) can be obtained by applying the release layer-forming composition of the present invention to a substrate and heating it.

[0076] Examples of the substrate (base material) include glass, plastic (polycarbonate, polymethacrylate, polystyrene, polyester, polyolefin, epoxy, melamine, triacetyl cellulose, ABS, AS, norbornene-based resin, etc.), metal (silicon wafer, etc.), metal compound (silicon nitride, etc.), wood, paper, slate, etc., and those containing glass, silicon nitride or silicon wafer are preferred. In particular, glass and silicon nitride are more preferred because the release layer obtained from the release layer forming composition according to the present invention has sufficient adhesion thereto. The substrate surface may be composed of a single material, or may be composed of two or more materials. The substrate surface may be composed of two or more materials in a certain range of the substrate surface and the remaining surface is composed of another material, or in a certain pattern such as a dot pattern or a line and space pattern on the entire substrate surface, among other materials.

[0077] The coating method is not particularly limited, but examples thereof include cast coating, spin coating, blade coating, dip coating, roll coating, bar coating, die coating, inkjet printing, and printing methods (relief printing, intaglio printing, planographic printing, screen printing, etc.).

[0078] In addition, methods for imidizing the polyamic acid contained in the composition for forming a release layer of the present invention include thermal imidization, in which the composition applied to a substrate is heated as is, and catalytic imidization, in which a catalyst is added to the composition and then heated.

[0079] The catalytic imidization of polyamic acid can be carried out by adding a catalyst to the release layer forming composition of the present invention, stirring to prepare a catalyst-added composition, and then applying it to a substrate and heating it. The amount of the catalyst is 0.1 to 30 times by mole, preferably 1 to 20 times by mole, the amount of the amic acid group. In addition, acetic anhydride or the like can be added as a dehydrating agent to the catalyst-added composition, and the amount is 1 to 50 times by mole, preferably 3 to 30 times by mole, the amount of the amic acid group.

[0080] As the imidization catalyst, a tertiary amine is preferably used, and examples of the tertiary amine include pyridine, substituted pyridines, imidazole, substituted imidazoles, picoline, quinoline, and isoquinoline.

[0081] The heating temperature during thermal imidization and catalytic imidization is usually appropriately determined within the range of 50 to 550°C, but is preferably 200°C or higher, and preferably 450°C or lower. By setting the heating temperature in this manner, it becomes possible to prevent the obtained film from becoming brittle and to allow the imidization reaction to proceed sufficiently. The heating time cannot be generally specified because it varies depending on the heating temperature, but is usually 5 minutes to 5 hours. The imidization rate may be, for example, in the range of 50 to 100%.

[0082] A preferred example of the heating mode in the present invention, taking into consideration the heat resistance of the resulting release layer and the versatility of the apparatus used, is a method in which the applied composition is heated at 50 to 100° C. for 1 to 30 minutes, then heated at 110 to 150° C. for 3 minutes to 1 hour, and then the heating temperature is gradually increased to finally heat at 200 to 300° C. for 10 minutes to 2 hours. In particular, it is preferable to heat at 80 to 120° C. for 5 to 30 minutes, and then at 230 to 300° C. for 30 minutes to 1 hour.

[0083] Examples of the heating device include a hot plate, an oven, etc. The heating atmosphere may be air or an inert gas, and may be normal pressure or reduced pressure.

[0084] The thickness of the release layer is usually about 0.01 to 10 μm, and preferably about 0.05 to 5 μm, and the thickness of the coating film before heating is adjusted to achieve a release layer of the desired thickness.

[0085] The release layer described above has excellent adhesion to a substrate, particularly a substrate such as glass or silicon nitride, and has appropriate adhesion to and appropriate release properties with a resin substrate. Therefore, the release layer according to the present invention can be suitably used in a manufacturing process for a flexible electronic device to release the resin substrate together with a circuit or the like formed on the resin substrate from the substrate without damaging the resin substrate.

[0086] (Method of manufacturing a flexible electronic device having a resin substrate) In the method of the present invention for producing a flexible electronic device having a resin substrate, for example, the release layer of the present invention is used.

[0087] An example of a method for producing a flexible electronic device using the release layer of the present invention will now be described. A release layer is formed on a substrate by the above-mentioned method using the composition for forming a release layer according to the present invention. A resin solution for forming a resin substrate is applied onto the release layer, and the coating is heated to form a resin substrate fixed to the substrate via the release layer according to the present invention. At this time, a resin substrate is formed with an area larger than that of the release layer so as to cover the entire release layer. Examples of the resin substrate include resin substrates made of polyimide resin, acrylic resin, and cycloolefin resin, which are typical resin substrates for flexible electronic devices, and examples of resin solutions for forming the resin substrate include polyimide solutions, polyamic acid solutions, acrylic polymer solutions, cycloolefin polymer solutions, and cycloolefin copolymer solutions. The resin substrate may be formed according to a conventional method.

[0088] Next, a desired circuit is formed on the resin substrate fixed to the base via the release layer according to the present invention, and then the resin substrate is cut, for example, along the release layer, and the resin substrate together with the circuit is peeled off from the release layer to separate the resin substrate from the base. At this time, a part of the base may be cut together with the release layer.

[0089] The present invention also provides the following method for producing an object to be peeled. A step of applying the composition for forming a release layer of the present invention onto a substrate and baking it to form a release layer; forming an object to be peeled on the peeling layer; and A step of peeling the object to be peeled from the peeling layer. The present invention provides a method for producing an object to be peeled, comprising the steps of:

[0090] In the above-mentioned manufacturing method, the firing conditions for forming the release layer can be the same as those described above. The "object to be peeled" may be a single layer or multiple layers. The layer immediately above the peeling layer of the "object to be peeled" (usually a resin substrate) should have good peelability from the peeling layer, or in other words, poor adhesion to the peeling layer, depending on the peeling layer used.

[0091] Furthermore, the present invention relates to a laminate for use in a flexible electronic device, comprising: A substrate; a release layer formed on the substrate; A resin substrate formed on the release layer; A laminate having the following structure is provided: EXAMPLES

[0092] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples. The abbreviations of the compounds used in the following examples, and the methods for measuring the weight average molecular weight and molecular weight distribution are as follows.

[0093] <Abbreviation of compound> PMDA: Pyromellitic dianhydride ODPA: 4,4'-oxydiphthalic anhydride DA-1: 1,2-bis(4-aminophenoxy)ethane DA-2: 1,3-bis(4-aminophenoxy)propane DA-3: 3,3'-diaminodiphenyl sulfone DA-4: 2,2'-bis(trifluoromethyl)benzidine ·PA: Phthalic anhydride ·Si-1: (3-ureidopropyl)trimethoxysilane Si-2: 1-(pyridin-2-yl)-3-(3-(trimethoxysilyl)propyl)urea Si-3: N-butyl-N'-[(3-trimethoxysilyl)propyl]thiourea Si-4: N-methyl-N'-[(3-trimethoxysilyl)propyl]thiourea Si-5: 3-Trimethoxysilylpropylsuccinic anhydride ·Si-6: 3-Aminopropyldiethoxymethylsilane Si-7: Tetramethoxysilane U-1: 1-Butylurea ·NMP: N-methyl-2-pyrrolidone EDM: Diethylene glycol ethyl methyl ether

[0094] The structures of Si-1 to Si-7 and U-1 are shown below. [ka]

[0095] <Measurement of weight average molecular weight and molecular weight distribution> The weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the polymer were measured using a GPC system manufactured by JASCO Corporation (column: Shodex KD803 and KD805; eluent: dimethylformamide / LiBr·H2O (30 mM) / H3PO4 (30 mM) / THF (1%); flow rate: 1.0 mL / min; column temperature: 50°C; Mw: standard polyethylene oxide equivalent value).

[0096] [1] Polymer synthesis Polyamic acid was synthesized by the following method. The polymer was not isolated from the resulting polymer-containing reaction liquid, but was diluted as described below to prepare a composition for forming a resin substrate or a composition for forming a release layer.

[0097] [Synthesis Example 1] Synthesis of polyamic acid A1 21.19g (86.8mmol) of DA-1 was dissolved in 283g of NMP, and then cooled to 5-15°C in an ice bath under a nitrogen atmosphere. 18.17g (83.3mmol) of PMDA and 71g of NMP were added to the resulting solution, and after stirring for 30 minutes, the mixture was reacted at 50°C for 24 hours. 0.64g (4.3mmol) of PA and 6g of NMP were added to the resulting solution, and the mixture was further reacted at 50°C for 6 hours to obtain polyamic acid A1. The Mw of polyamic acid A1 was 24,330, and Mw / Mn was 1.8.

[0098] [Synthesis Example 2] Synthesis of polyamic acid A2 21.54 g (88.2 mmol) of DA-1 was dissolved in 288 g of NMP, and then cooled to 5 to 15° C. in an ice bath under a nitrogen atmosphere. 18.46 g (84.6 mmol) of PMDA and 72 g of NMP were added to the resulting solution, and after stirring for 30 minutes, the mixture was reacted at 50° C. for 24 hours to obtain polyamic acid A2. The Mw of polyamic acid A2 was 18,960, and the Mw / Mn was 1.9.

[0099] [Synthesis Example 3] Synthesis of polyamic acid A3 17.58g (72.0mmol) of DA-1 was dissolved in 284g of NMP, and then cooled to 5-15°C in an ice bath under a nitrogen atmosphere. 21.88g (70.5mmol) of ODPA and 71g of NMP were added to the obtained solution, and after stirring for 30 minutes, the mixture was reacted at 50°C for 24 hours. 0.53g (3.6mmol) of PA and 5g of NMP were added to the obtained solution, and the mixture was further reacted at 50°C for 6 hours to obtain polyamic acid A3. The Mw of polyamic acid A3 was 32,820, and Mw / Mn was 1.9.

[0100] [Synthesis Example 4] Synthesis of polyamic acid A4 11.84g (48.5mmol) of DA-1 and 1.39g (5.4mmol) of DA-2 were dissolved in 213g of NMP, and then cooled to 5-15°C in an ice bath under a nitrogen atmosphere. 16.37g (52.7mmol) of ODPA and 53g of NMP were added to the obtained solution, and after stirring for 30 minutes, the mixture was reacted at 50°C for 24 hours. 0.40g (2.7mmol) of PA and 4g of NMP were added to the obtained solution, and the mixture was further reacted at 50°C for 6 hours to obtain polyamic acid A4. The Mw of polyamic acid A4 was 19,350, and Mw / Mn was 1.9.

[0101] [Synthesis Example 5] Synthesis of polyamic acid A5 6.51g (26.7mmol) of DA-1 and 6.89g (26.7mmol) of DA-2 were dissolved in 213g of NMP, and then cooled to 5-15°C in an ice bath under a nitrogen atmosphere. 16.21g (52.2mmol) of ODPA and 53g of NMP were added to the obtained solution, and after stirring for 30 minutes, the mixture was reacted at 50°C for 24 hours. 0.40g (2.7mmol) of PA and 4g of NMP were added to the obtained solution, and the mixture was further reacted at 50°C for 6 hours to obtain polyamic acid A5. The Mw of polyamic acid A5 was 23,020, and Mw / Mn was 1.9.

[0102] [Synthesis Example F1] Synthesis of polyamic acid F1 48.8g (196mmol) of DA-3 and 4.9g (22mmol) of DA-4 were dissolved in 224g of NMP. 66.3g (214mmol) of ODPA and 56g of NMP were added to the resulting solution, and after stirring for 30 minutes, the mixture was reacted at 50°C for 24 hours to obtain polyamic acid F1. The Mw of polyamic acid F1 was 43,130, and Mw / Mn was 2.6.

[0103] [2] Preparation of composition for forming resin substrate [Preparation Example 1] Preparation of composition F1 for forming resin substrate The reaction liquid obtained in Synthesis Example F1 was used as it was as composition F1 for forming a resin substrate.

[0104] [3] Preparation of composition for forming release layer [Example 1-1] 4.8 mg (0.022 mmol, 1 mol% relative to the diamine) of Si-1 diluted to 10% by mass with NMP was added to 10.0 g of the reaction liquid obtained in Synthesis Example 1, and the mixture was stirred for 30 minutes and then stirred for 4 hours at 50° C. EDM and NMP were added to the reaction liquid obtained, and the mixture was diluted to a polymer concentration of 5% by mass and EDM concentration of 20% by mass, to obtain a release layer forming composition 1.

[0105] [Examples 1-2 to 1-13] Compositions 2 to 13 for forming a release layer, each having a polymer concentration of 5% by mass and EDM of 20% by mass, were obtained in the same manner as in Example 1-1, except that the reaction liquid shown in Table 1 and additives diluted to 10% by mass with NMP were used.

[0106] [Comparative Example 1-1] The reaction liquid obtained in Synthesis Example 1 was diluted with EDM and NMP to a polymer concentration of 5 mass % and an EDM concentration of 20 mass %, to obtain a composition 14 for forming a release layer.

[0107] [Comparative Example 1-2] A composition 15 for forming a release layer having a polymer concentration of 5% by mass and an EDM concentration of 20% by mass was obtained in the same manner as in Comparative Example 1-1, except that the reaction liquid obtained in Synthesis Example 3 was used instead of the reaction liquid obtained in Synthesis Example 1.

[0108] [Comparative Examples 1-3 to 1-4] Compositions 16 to 17 for forming a release layer, each having a polymer concentration of 5% by mass and EDM of 20% by mass, were obtained in the same manner as in Example 1-1, except that the reaction liquid shown in Table 1 and additives diluted to 10% by mass with NMP were used.

[0109] [Reference example 1-1] A release layer-forming composition 18 having a polymer concentration of 5% by mass and EDM of 20% by mass was obtained in the same manner as in Example 1-1, except that the reaction liquid shown in Table 1 and additives diluted to 10% by mass with NMP were used.

[0110] [Table 1]

[0111] [4] Formation of peeling layer [Example 2-1] Using a spin coater, the composition for forming a release layer obtained in Example 1-1 was applied onto a 100 mm x 100 mm glass substrate and a silicon nitride substrate (hereinafter the same). The resulting coating film was then heated on a hot plate at 80°C for 2 minutes, then at 120°C for 5 minutes, and then at 240°C for 60 minutes to form a release layer having a thickness of 100 to 200 nm on each of the glass substrate and the silicon nitride substrate, thereby obtaining substrates with a release layer (glass substrate with a release layer, and silicon nitride substrate with a release layer).

[0112] [Examples 2-2 to 2-13] A release layer was formed in the same manner as in Example 2-1, except that the compositions for forming a release layer obtained in Examples 1-2 to 1-13 were used instead of the composition for forming a release layer obtained in Example 1-1, and a substrate with a release layer was obtained.

[0113] [Comparative Examples 2-1 to 2-4] A release layer was formed in the same manner as in Example 2-1, except that the compositions for forming a release layer obtained in Comparative Examples 1-1 to 1-4 were used instead of the composition for forming a release layer obtained in Example 1-1, and a substrate with a release layer was obtained.

[0114] [Reference example 2-1] A release layer was formed in the same manner as in Example 2-1, except that the composition for forming a release layer obtained in Reference Example 1-1 was used instead of the composition for forming a release layer obtained in Example 1-1, and a substrate with a release layer was obtained.

[0115] [5] Formation of resin substrate and evaluation of peelability [Example 3-1] Using a spin coater, the resin substrate forming composition F1 was applied onto the release layer (resin thin film) on the glass substrate with the release layer obtained in Example 2-1.Then, the obtained coating film was heated using a hot plate to form a resin substrate layer.The baking conditions of the resin substrate forming composition F1 are described below. The film was heated at 80° C. for 2 minutes using a hot plate, then at 120° C. for 5 minutes using a hot plate, and further heated at 240° C. for 60 minutes using a hot plate to form a resin substrate with a thickness of approximately 10 μm on the release layer.

[0116] [Examples 3-2 to 3-13, Comparative Examples 3-1 to 3-4, Reference Example 3-1] A resin substrate was formed on a release layer in the same manner as in Example 3-1, except that the glass substrates with a release layer obtained in Examples 2-2 to 2-13, Comparative Examples 2-1 to 2-4, and Reference Example 2-1 were used instead of the glass substrate with a release layer obtained in Example 2-1.

[0117] <Evaluation of peel strength of resin substrate> The resin substrates of the resin substrates and the glass substrates with a release layer obtained in Examples 3-1 to 3-13, Comparative Examples 3-1 to 3-4, and Reference Example 3-1 were cut together with the release layer to prepare strips of 25 mm x 70 mm. Furthermore, Cellotape (registered trademark) (CT-24, manufactured by Nichiban Co., Ltd.) was applied onto the strips, and then the resin substrates were peeled off from the release layer at a peel angle of 90° and a peel speed of 300 mm / min using an autograph AGS-X500N (manufactured by Shimadzu Corporation), and the peel force was measured. Those that could not be peeled off were deemed not peelable. The results are shown in Table 2. [Evaluation Criteria] a: Peel force less than 0.05N / 25mm b: Peeling force of 0.05N / 25mm or more and less than 0.10N / 25mm c: Peeling force of 0.10N / 25mm or more

[0118] [6] Adhesion evaluation <Cross-cut test> The cross-cut test of the substrates with a release layer obtained in Examples 2-1 to 2-13, Comparative Examples 2-1 to 2-4, and Reference Example 2-1 (glass substrate with a release layer, and silicon nitride substrate with a release layer) was carried out as follows. The results are shown in Table 2. (1) Using a cutter, 100 square sections measuring 1 mm on each side were created on the release layer. (2) After that, adhesive tape (Sellotape (registered trademark)) was attached to the square section, and a peeling process was carried out. (3) After the peeling step, the number of the above-mentioned square sections remaining on the substrate was counted and evaluated according to the following evaluation index. <Indicators of cross-cut test results> As a result of the cross-cut test, the degree of peeling is indicated by the following index. ○: No peeling (all 100 square sections remain on the substrate). ×: Peeling occurred (peeling of one or more square sections was observed).

[0119] <Resin substrate peeling test> The resin substrate / glass substrate with a release layer obtained in Examples 3-1 to 3-13, Comparative Examples 3-1 to 3-4, and Reference Example 3-1 were evaluated for peel strength, and the release layer remaining on the glass substrate was confirmed. <Results after resin substrate peeling test> As a result of the peeling test, the degree of peeling is indicated by the following index. ○: No peeling. ×: Peeling occurred. "No peeling" refers to a state in which the release layer remains on the glass substrate after the peel strength evaluation. "Peeled" refers to a state in which the release layer was peeled off from the glass substrate together with the resin substrate when the peel strength was evaluated.

[0120] [Table 2]

[0121] From the results in Table 2, it was confirmed that the release layer of the Example had excellent adhesion to the glass substrate and the silicon nitride substrate, and was easily peeled off from the resin substrate. On the other hand, it was confirmed that the release layer of the Comparative Example was easily peeled off from the resin substrate, but had poor adhesion to the glass substrate and the silicon nitride substrate.

Claims

1. A release layer-forming composition comprising a polyamic acid, a silane coupling agent represented by the following formula (E), and an organic solvent: 【Chemistry 1】 (In formula (E), X １ ~X ３ each independently represents an alkoxy group, an aralkyloxy group, an acyloxy group, a halogen atom, or an alkyl group (provided that X １ ~X ３ Except when all of the groups represent alkyl groups. R １ represents an alkylene group having 1 to 6 carbon atoms. R ２ represents a group represented by the following formula (E-1) or formula (E-2): 【Chemistry 2】 (In formula (E-1), R １１ ~R １３ each independently represents a hydrogen atom or an organic group having 1 to 6 carbon atoms (provided that R １１ ~R １３ At least one of represents a hydrogen atom. Y represents an oxygen atom or a sulfur atom. In formula (E-1) and formula (E-2), * represents a bond.

2. the polyamic acid is a reaction product of raw material components including a tetracarboxylic dianhydride and a diamine component, the tetracarboxylic dianhydride comprises an aromatic tetracarboxylic dianhydride, The diamine component comprises an aromatic diamine. The release layer forming composition according to claim 1 .

3. The composition for forming a release layer according to claim 2, wherein the aromatic tetracarboxylic dianhydride is represented by the following formula (1-1) or formula (1-2): 【Chemistry 3】 (In formula (1-1), Ar １ represents a tetravalent group obtained by removing two pairs of adjacent hydrogen atoms from a benzene ring which may have a substituent, or a tetravalent group obtained by removing two pairs of adjacent hydrogen atoms from a naphthalene ring which may have a substituent. In formula (1-2), X １ represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), or a group represented by the following formula (1-2-1). R ａ each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. Each n independently represents an integer of 0 to 3. One (R ａ ) ｎ When n is 2 or more, two or more R ａ may be the same or different.) 【Chemistry 4】 (In formula (1-2-1), Y １ and Y ２ each independently represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, or -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). Ar ２ represents a divalent group obtained by removing two hydrogen atoms from a phenylene group which may have a substituent, or a biphenyl group which may have a substituent. * represents a bond.)

4. The composition for forming a release layer according to claim 2, wherein the aromatic diamine is represented by the following formula (2-1) or formula (2-2): 【Chemistry 5】 (In formula (2-1), X １１ represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), or a group represented by the following formula (2-1-1). R ｂ each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. Each m independently represents an integer of 0 to 4. One (R ｂ ) ｍ In the formula, when m is 2 or more, two or more R ｂ may be the same or different. In formula (2-2), X １２ represents an -NH- group, an -O- group, or an -S- group. R ｃ each independently represents a halogen atom or an alkyl group having 1 to 4 carbon atoms. p1 represents an integer of 0 to 3. p2 represents an integer of 0 to 4. (R ｃ ) ｐ１ When p1 is 2 or more, two or more R ｃ may be the same or different. (R ｃ ) ｐ２ When p2 is 2 or more, two or more R ｃ may be the same or different.) 【Chemistry 6】 (In formula (2-1-1), Y １１ and Y １２ each independently represents a single bond, an ether bond, a carbonyl bond, an ester bond, a urethane bond, a urea bond, a thioether bond, a sulfonyl bond, or -C(=O)N(-R)- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). Z １１ represents a divalent hydrocarbon group having 1 to 20 carbon atoms. * represents a bond.)

5. The aromatic diamine is represented by the formula (2-1), X in the formula (2-1) １１ represents a group represented by formula (2-1-1), The release layer forming composition according to claim 4 .

6. The composition for forming a release layer according to claim 2 , wherein the raw material components further include a dicarboxylic acid anhydride.

7. 2. The composition for forming a release layer according to claim 1, wherein the content of the silane coupling agent is 0.01% by mass to 15% by mass with respect to the polyamic acid.

8. A release layer formed from the composition for forming a release layer according to claim 1 .

9. A method for producing a flexible electronic device having a resin substrate, using the release layer according to claim 8.

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