WO2017115824A1

WO2017115824A1 - Polyimide film layered body

Info

Publication number: WO2017115824A1
Application number: PCT/JP2016/088993
Authority: WO
Inventors: 卓也岡; 幸徳小濱; 美晴中川; 久野　信治; 毅 ▲高▼橋; 暁良金子; 山田　健史
Original assignee: 宇部興産株式会社
Priority date: 2015-12-28
Filing date: 2016-12-27
Publication date: 2017-07-06
Also published as: JP2017119421A; TW201736138A; JP6119910B1

Abstract

Provided is a polyimide film layered body having enhanced adhesion to another functional layer while making use of the characteristics of a conventional polyimide film. This polyimide film layered body has a polyimide film, and a coating layer formed from a cured material of a coating composition containing a polyurethane resin and a (meth)acrylate compound on the surface of the polyimide film.

Description

Polyimide film laminate

The present invention relates to a polyimide film laminate having excellent surface adhesion.

Polyimide films have been widely used in the fields of electric / electronic devices and semiconductors because they are excellent in heat resistance, chemical resistance, mechanical strength, electrical properties, dimensional stability, and the like. On the other hand, in recent years, with the arrival of an advanced information society, development of optical materials such as a liquid crystal alignment film and a protective film for a color filter in the display device field, such as an optical fiber and an optical waveguide in the optical communication field, is progressing. In particular, in the field of display devices, a plastic substrate that is lightweight and excellent in flexibility as a substitute for a glass substrate has been studied, and a display that can be bent and rolled has been actively developed. For this reason, there is a demand for higher performance optical materials that can be used for such applications.

Aromatic polyimide is essentially yellowish brown due to intramolecular conjugation and the formation of charge transfer complexes. For this reason, as a means to suppress coloration, for example, introduction of fluorine atoms into the molecule, imparting flexibility to the main chain, introduction of bulky groups as side chains, etc. inhibits intramolecular conjugation and charge transfer complex formation. And the method of expressing transparency is proposed (for example, patent document 1).

In addition, a method for expressing transparency by using a semi-alicyclic or fully alicyclic polyimide that does not form a charge transfer complex in principle has been proposed (for example, Patent Documents 2 to 5).

Special table 2010-538103 gazette JP 2012-41529 A International Publication No. 2014/046064 JP 2009-286706 A JP 2014-92775 A International Publication No. 2014/092422 JP2015-58595A

Polyimide is excellent in heat resistance and chemical resistance, but often has insufficient adhesion and adhesion to other layers. For this reason, the layer which has a specific function may not be provided in the polyimide film surface, but it will become a problem when aiming at the use expansion of a polyimide film.

In Patent Document 6 (International Publication No. 2014/092422; published Japanese Patent Application No. 2016-501144), the polyimide film contains acrylate groups and has 2 to 5 isocyanate groups per molecule. A transparent polyimide substrate comprising a cured layer of a polyisocyanate is disclosed. However, the polyimide substrate described in Patent Document 6 is characterized in that the cured layer of polyisocyanate has scratch resistance, and is not an invention that improves the adhesion and adhesion between the polyimide film and other layers. The polyisocyanate is different from the present invention described below in that it has an acrylate group and an isocyanate group in the molecule.

Patent Document 7 (Japanese Patent Application Laid-Open No. 2015-58595) describes a composite film having a support and a surface coating layer containing a polymer of urethane (meth) acrylate monomer. However, the coating layer formed of the hardened | cured material of the composition containing the urethane resin different from a urethane (meth) acrylate monomer or its polymer and a (meth) acrylate compound is not described. Moreover, although polyimide is mentioned as an example of a support body, there is no Example which used the polyimide as a support body, and properties, such as adhesiveness, are not proven.

The present invention has been made in view of the above problems, and an object thereof is to provide a polyimide film laminate having improved adhesion with other functional layers while taking advantage of the conventional characteristics of polyimide films. To do.

The present invention relates to the following items.

1. Polyimide film,
A polyimide film laminate having a coating layer formed of a cured product of a coating composition containing a polyurethane resin and a (meth) acrylate compound on the surface of the polyimide film (however, the polyurethane resin is , Urethane (meth) acrylate monomer and polymer thereof are not included.)

2. The polyimide which comprises the said polyimide film contains the repeating unit represented by following General formula (1), The polyimide film laminated body of said claim | item 1 characterized by the above-mentioned.

(In the formula, X ₁ is a tetravalent group having an aromatic ring or alicyclic structure, and Y ₁ is a divalent group having an aromatic ring or alicyclic structure.)
3. The content of the repeating unit represented by the chemical formula (1) in which X ₁ is a tetravalent group having an alicyclic structure and Y ₁ is a divalent group having an alicyclic structure is based on the total repeating units. The polyimide film laminate according to Item 2, wherein the polyimide film laminate is 50 mol% or less.

4). 3. The polyimide film laminate according to item 2, wherein X ₁ in chemical formula (1) is a tetravalent group having an aromatic ring, and Y ₁ is a divalent group having an aromatic ring. .

5). 3. The polyimide film laminate according to item 2, wherein X ₁ in chemical formula (1) is a tetravalent group having an alicyclic structure, and Y ₁ is a divalent group having an aromatic ring. .

6). 3. The polyimide film laminate according to item 2, wherein X ₁ in chemical formula (1) is a tetravalent group having an aromatic ring, and Y ₁ is a divalent group having an alicyclic structure. .

7. Item 7. The polyimide according to any one of Items 1 to 6, wherein the content of the (meth) acrylate compound is 5 to 50% by weight based on the solid content based on the resin component in the coating composition. Film laminate.

8. Item 8. The polyimide film laminate according to any one of Items 1 to 7, wherein the polyurethane resin includes a structure in which a polycarbonate polyol and a polyisocyanate compound are reacted.

9. Item 9. The polyimide film laminate according to any one of Items 1 to 8, wherein the coating layer has a thickness of 10 nm or more and less than 5 μm.

10. 10. The polyimide film laminate according to any one of items 1 to 9, further comprising a surface layer on the surface of the coating layer, wherein the surface has a pencil hardness of 2H or more.

11. The thickness of the coating layer is 10 nm or more and less than 5 μm, further has a surface layer on the surface of the coating layer, and the pencil hardness of the surface layer is 2H or more, The polyimide film laminated body of any one of Claims 1.

12. Item 12. The polyimide film laminate according to Item 10 or 11, wherein the surface layer is formed of a cured product of a curable resin composition containing at least a curable resin component and an inorganic filler.

13. Applying a coating composition containing a polyurethane resin and a (meth) acrylate compound to the surface of the polyimide film;
A method of producing a polyimide film laminate, wherein the coating film of the coating composition is cured to form a coating layer (wherein the polyurethane resin comprises a urethane (meth) acrylate monomer and its weight). Does not include coalescence.)

14 Applying a curable resin composition containing at least a curable resin component and an inorganic filler to the surface of the coating layer of the polyimide film laminate according to any one of Items 1 to 9,
And a step of curing the coating film of the curable resin composition to form a surface layer.

According to the present invention, a polyimide film laminate having improved adhesion to other functional layers while taking advantage of conventional characteristics of polyimide film such as chemical resistance, mechanical strength, electrical characteristics, and dimensional stability. Can be provided.

In particular, when a highly transparent polyimide is used, good adhesion can be imparted to a polyimide film having excellent characteristics without impairing transparency. Thereby, it becomes possible to form a further layer in a polyimide film, and the use of a polyimide film can be extended greatly.

Moreover, according to one aspect of the present invention, the yellowness (YI) of the polyimide film laminate can also be improved.

The polyimide film laminate of the present invention has a polyimide film and a coating layer formed on the surface thereof. Here, the polyimide film laminate of the present invention has, for example, products such as electronic products, optical products, display products, etc., in addition to forms (forms distributed as film products) as polyimide films having a coating layer formed on the surface. (Including parts, semi-finished products being manufactured, etc.). Accordingly, it includes a form after another layer is formed or laminated on the coating layer. In addition, the polyimide film laminate of the present invention was produced by manufacturing a semi-finished product using a polyimide film, and then forming or laminating another layer on the coating layer, in which a coating layer was formed on the polyimide film surface. Including things. Moreover, the coating layer may be formed only on one side of the polyimide film or may be formed on both sides depending on the application. Further, it may be formed on the entire surface of one side or both sides of the film, or may be formed only on a part of the surface.

<< Polyimide film >>
The polyimide film used in the present invention is not particularly limited, and the tetracarboxylic acid component and the diamine component are appropriately composed of a polyimide selected from an aromatic compound and an alicyclic compound. For example, a wholly aromatic polyimide, a semi-alicyclic polyimide, and a wholly alicyclic polyimide may be mentioned.

That is, the polyimide used in the present invention contains a repeating unit represented by the following general formula (1).

(In the formula, X ₁ is a tetravalent group having an aromatic ring or alicyclic structure, and Y ₁ is a divalent group having an aromatic ring or alicyclic structure.)

Although not particularly limited, since the obtained polyimide is excellent in heat resistance, X ₁ in the general formula (1) is a tetravalent group having an aromatic ring, and Y ₁ is 2 having an aromatic ring. It is preferably a valent group. Moreover, since the polyimide obtained is excellent in heat resistance and excellent in transparency, it is preferable that X ₁ is a tetravalent group having an alicyclic structure and Y ₁ is a divalent group having an aromatic ring. . Moreover, since the polyimide obtained is excellent in heat resistance and dimensional stability, X ₁ is a tetravalent group having an aromatic ring, and Y ₁ is a divalent group having an alicyclic structure. preferable.

From the viewpoint of the properties of the resulting polyimide, such as transparency, mechanical properties, and heat resistance, X ₁ is a tetravalent group having an alicyclic structure, and Y ₁ is a divalent group having an alicyclic structure. The content of the repeating unit represented by the formula (1) is preferably 50 mol% or less, more preferably 30 mol% or less or less than 30 mol%, more preferably 10 mol%, based on all repeating units. The following is preferable.

In one embodiment, X ₁ is a tetravalent group having an aromatic ring, and Y ₁ is a divalent group having an aromatic ring. However, the total is preferably 50 mol% or more, more preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, particularly preferably 100 mol%, based on all repeating units. Preferably there is. In this embodiment, when a highly transparent polyimide is particularly required, the polyimide preferably contains a fluorine atom. That is, the polyimide is a divalent group in which X ₁ is a tetravalent group having an aromatic ring containing a fluorine atom and / or Y ₁ has an aromatic ring containing a fluorine atom. It is preferable that 1 type or more of the repeating unit of the said Chemical formula (1) which is group of is included.

In one embodiment, the polyimide is one or more repeating units of the above chemical formula (1), wherein X ₁ is a tetravalent group having an alicyclic structure and Y ₁ is a divalent group having an aromatic ring. The total content is preferably 50 mol% or more, more preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, particularly preferably 100 mol, based on all repeating units. It is preferable that it is mol%.

In one embodiment, the polyimide is one or more repeating units of the above formula (1), wherein X ₁ is a tetravalent group having an aromatic ring and Y ₁ is a divalent group having an alicyclic structure. The total content is preferably 50 mol% or more, more preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, particularly preferably 100 mol, based on all repeating units. It is preferable that it is mol%.

The tetravalent group having an aromatic ring of X ₁ is preferably a tetravalent group having an aromatic ring having 6 to 40 carbon atoms.

Examples of the tetravalent group having an aromatic ring include the following.

(In the formula, Z ₁ is a direct bond or the following divalent group:

One of them. In the formula, Z ₂ is a divalent organic group, Z _{3 and} Z ₄ are each independently an amide bond, an ester bond and a carbonyl bond, and Z ₅ is an organic group containing an aromatic ring. )

Specific examples of Z ₂ include an aliphatic hydrocarbon group having 2 to 24 carbon atoms and an aromatic hydrocarbon group having 6 to 24 carbon atoms.

Specific examples of Z ₅ include aromatic hydrocarbon groups having 6 to 24 carbon atoms.

As the tetravalent group having an aromatic ring, since the high heat resistance and high transparency of the obtained polyimide can be compatible, the following are particularly preferable.

(In the formula, Z ₁ is a direct bond or a hexafluoroisopropylidene bond.)

Here, Z ₁ is more preferably a direct bond, and the resulting polyimide has high heat resistance and a low linear thermal expansion coefficient. In particular, when the diamine-derived structure is an alicyclic structure, high transparency is also obtained. Can be compatible.

Examples of the tetracarboxylic acid component that gives a repeating unit of the chemical formula (1) in which X ₁ is a tetravalent group having an aromatic ring include 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid, pyromellitic acid, 3,3 ′, 4,4′-benzophenonetetra Carboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4′-biphenyltetracarboxylic acid, 4,4′-oxydiphthalic acid, bis (3,4-dicarboxyphenyl) ) Sulfone, m-terphenyl-3,4,3 ′, 4′-tetracarboxylic acid, p-terphenyl-3,4,3 ′, 4′-tetracarboxylic acid, biscarboxyphenyldimethylsilane, Streaks carboxyphenoxy diphenyl sulfide, or sulfonyl di phthalate, these tetracarboxylic dianhydrides, tetracarboxylic acid silyl ester, tetracarboxylic acid esters, derivatives of such tetracarboxylic acid chloride. Examples of the tetracarboxylic acid component that gives a repeating unit of the chemical formula (1) in which X ₁ is a tetravalent group having an aromatic ring containing a fluorine atom include 2,2-bis (3,4-dicarboxyphenyl). ) Derivatives such as hexafluoropropane, tetracarboxylic dianhydrides, tetracarboxylic acid silyl esters, tetracarboxylic acid esters, and tetracarboxylic acid chlorides thereof. A tetracarboxylic acid component may be used independently and can also be used in combination of multiple types.

The tetravalent group having an alicyclic structure of X ₁ is preferably a tetravalent group having an alicyclic structure having 4 to 40 carbon atoms, more preferably at least one aliphatic 4- to 12-membered ring, more preferably an aliphatic group. More preferably, it has a 4-membered ring or an aliphatic 6-membered ring. The following are mentioned as a tetravalent group which has a preferable aliphatic 4-membered ring or an aliphatic 6-membered ring.

(Wherein R ₃₁ to R ₃₈ are each independently a direct bond or a divalent organic group. R ₄₁ to R ₄₇ are each independently represented by the formula: —CH ₂ —, —CH═CH—, This represents one selected from the group consisting of groups represented by —CH ₂ CH ₂ —, —O—, and —S—, wherein R ₄₈ is an organic group containing an aromatic ring or alicyclic structure.

R ₃₁ , R ₃₂ , R ₃₃ , R ₃₄ , R ₃₅ , R ₃₆ , R ₃₇ , R ₃₈ are specifically a direct bond, an aliphatic hydrocarbon group having 1 to 6 carbon atoms, or Examples include an oxygen atom (—O—), a sulfur atom (—S—), a carbonyl bond, an ester bond, and an amide bond.

Examples of the organic group containing an aromatic ring as R ₄₈ include the following.

(Wherein W ₁ is a direct bond or a divalent organic group, n ₁₁ to n ₁₃ each independently represents an integer of 0 to 4, and R ₅₁ , R ₅₂ and R ₅₃ are each independently And an alkyl group having 1 to 6 carbon atoms, a halogen group, a hydroxyl group, a carboxyl group, or a trifluoromethyl group.)

Specific examples of W ₁ include a direct bond, a divalent group represented by the following formula (5), and a divalent group represented by the following formula (6).

(R ₆₁ to R ₆₈ in the formula (6) each independently represent a direct bond or a divalent group represented by the formula (5).)

As the tetravalent group having an alicyclic structure, the following are particularly preferable because the polyimide obtained can have both high heat resistance, high transparency, and a low linear thermal expansion coefficient.

Examples of the tetracarboxylic acid component that gives the repeating unit of the formula (1) in which X ₁ is a tetravalent group having an alicyclic structure include 1,2,3,4-cyclobutanetetracarboxylic acid, isopropylidenediphenoxybis Phthalic acid, cyclohexane-1,2,4,5-tetracarboxylic acid, [1,1'-bi (cyclohexane)]-3,3 ', 4,4'-tetracarboxylic acid, [1,1'-bi (Cyclohexane)]-2,3,3 ′, 4′-tetracarboxylic acid, [1,1′-bi (cyclohexane)]-2,2 ′, 3,3′-tetracarboxylic acid, 4,4′- Methylenebis (cyclohexane-1,2-dicarboxylic acid), 4,4 '-(propane-2,2-diyl) bis (cyclohexane-1,2-dicarboxylic acid), 4,4'-oxybis (cyclohexane-1,2) -Dicarboxylic acid), 4,4 ' Thiobis (cyclohexane-1,2-dicarboxylic acid), 4,4'-sulfonylbis (cyclohexane-1,2-dicarboxylic acid), 4,4 '-(dimethylsilanediyl) bis (cyclohexane-1,2-dicarboxylic acid) ), 4,4 ′-(tetrafluoropropane-2,2-diyl) bis (cyclohexane-1,2-dicarboxylic acid), octahydropentalene-1,3,4,6-tetracarboxylic acid, bicyclo [2 2.1] heptane-2,3,5,6-tetracarboxylic acid, 6- (carboxymethyl) bicyclo [2.2.1] heptane-2,3,5-tricarboxylic acid, bicyclo [2.2. 2] Octane-2,3,5,6-tetracarboxylic acid, bicyclo [2.2.2] oct-5-ene-2,3,7,8-tetracarboxylic acid, tricyclo [4.2.2. 02 , 5] decane-3,4,7,8-tetracarboxylic acid, tricyclo [4.2.2.02,5] dec-7-ene-3,4,9,10-tetracarboxylic acid, 9-oxa Tricyclo [4.2.1.02,5] nonane-3,4,7,8-tetracarboxylic acid, norbornane-2-spiro-α-cyclopentanone-α′-spiro-2 ″ -norbornane 5 , 5 ″, 6,6 ″ -tetracarboxylic acid, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethananaphthalene-2c, 3c, 6c, 7c-tetracarboxylic acid, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2t, 3t, 6c, 7c-tetracarboxylic acid, tetracarboxylic dianhydrides, tetracarboxylic silyl esters, tetracarboxylic acid es Le, include derivatives such as tetracarboxylic acid chloride. A tetracarboxylic acid component may be used independently and can also be used in combination of multiple types.

The divalent group having an aromatic ring of Y ₁ is preferably a divalent group having an aromatic ring having 6 to 40 carbon atoms, more preferably 6 to 20 carbon atoms.

Examples of the divalent group having an aromatic ring include the following.

Here, since the polyimide obtained can have both high heat resistance, high transparency, and a low coefficient of linear thermal expansion, W ₁ is a direct bond, or a formula: —NHCO—, —CONH—, —COO—, —OCO—. It is especially preferable that it is 1 type selected from the group which consists of group represented by these. W ₁ is a group in which R ₆₁ to R ₆₈ are a direct bond, or one selected from the group consisting of groups represented by the formula: —NHCO—, —CONH—, —COO—, —OCO—. It is also particularly preferable that it is any of the divalent groups represented by the formula (6).

Examples of the diamine component that gives a repeating unit of the chemical formula (1) in which Y ₁ is a divalent group having an aromatic ring include p-phenylenediamine, m-phenylenediamine, benzidine, and 3,3′-diamino-biphenyl. 2,2'-bis (trifluoromethyl) benzidine, 3,3'-bis (trifluoromethyl) benzidine, m-tolidine, 4,4'-diaminobenzanilide, 3,4'-diaminobenzanilide, N , N′-bis (4-aminophenyl) terephthalamide, N, N′-p-phenylenebis (p-aminobenzamide), 4-aminophenoxy-4-diaminobenzoate, bis (4-aminophenyl) terephthalate, biphenyl -4,4'-dicarboxylic acid bis (4-aminophenyl) ester, p-phenylenebis (p-aminobenzo) ), Bis (4-aminophenyl)-[1,1′-biphenyl] -4,4′-dicarboxylate, [1,1′-biphenyl] -4,4′-diyl bis (4-amino) Benzoate), 4,4'-oxydianiline, 3,4'-oxydianiline, 3,3'-oxydianiline, p-methylenebis (phenylenediamine), 1,3-bis (4-aminophenoxy) benzene 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3- Aminophenoxy) biphenyl, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, bis (4-amino) Phenyl) sulfone, 3,3′-bis (trifluoromethyl) benzidine, 3,3′-bis ((aminophenoxy) phenyl) propane, 2,2′-bis (3-amino-4-hydroxyphenyl) hexafluoro Propane, bis (4- (4-aminophenoxy) diphenyl) sulfone, bis (4- (3-aminophenoxy) diphenyl) sulfone, octafluorobenzidine, 3,3′-dimethoxy-4,4′-diaminobiphenyl, 3 , 3'-dichloro-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,4-bis (4-aminoanilino) -6-amino-1,3,5- Triazine, 2,4-bis (4-aminoanilino) -6-methylamino-1,3,5-triazine, 2,4-bis (4-aminoanilino) 6-ethyl-1,3,5-triazine, 2,4-bis (4-aminoanilino) -6-anilino-1,3,5-triazine. Examples of the diamine component that gives the repeating unit of the chemical formula (1) in which Y ₁ is a divalent group having an aromatic ring containing a fluorine atom include 2,2′-bis (trifluoromethyl) benzidine, 3, 3′-bis (trifluoromethyl) benzidine, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2 ′ -Bis (3-amino-4-hydroxyphenyl) hexafluoropropane. A diamine component may be used independently and can also be used in combination of multiple types.

The divalent group having an alicyclic structure of Y ₁ is preferably a divalent group having an alicyclic structure having 4 to 40 carbon atoms, more preferably at least one aliphatic 4- to 12-membered ring, more preferably an aliphatic group. More preferably, it has a 6-membered ring.

Examples of the divalent group having an alicyclic structure include the following.

(Wherein V ₁ and V ₂ are each independently a direct bond or a divalent organic group, n ₂₁ to n ₂₆ each independently represents an integer of 0 to 4, R ₈₁ to R ₈₆ Are each independently an alkyl group having 1 to 6 carbon atoms, a halogen group, a hydroxyl group, a carboxyl group, or a trifluoromethyl group, and R ₉₁ , R ₉₂ , and R ₉₃ are each independently represented by the formula: —CH ₂ —, (This is one selected from the group consisting of groups represented by —CH═CH—, —CH ₂ CH ₂ —, —O—, and —S—.)

Specific examples of V ₁ and V ₂ include a direct bond and a divalent group represented by the above formula (5).

As the divalent group having an alicyclic structure, the following are particularly preferable because the polyimide obtained can have both high heat resistance and low linear thermal expansion coefficient.

Among the divalent groups having an alicyclic structure, the following are preferable.

Examples of the diamine component that gives the repeating unit of the chemical formula (1) in which Y ₁ is a divalent group having an alicyclic structure include 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4-diamino-2-ethylcyclohexane, 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-isopropylcyclohexane, 1,4-diamino-2-n-butylcyclohexane, 1, 4-diamino-2-isobutylcyclohexane, 1,4-diamino-2-sec-butylcyclohexane, 1,4-diamino-2-tert-butylcyclohexane, 1,2-diaminocyclohexane, 1,3-diaminocyclobutane 1,4-bis (aminomethyl) cyclohexane, 1,3-bis (aminomethyl) cyclohexane Sun, diaminobicycloheptane, diaminomethylbicycloheptane, diaminooxybicycloheptane, diaminomethyloxybicycloheptane, isophoronediamine, diaminotricyclodecane, diaminomethyltricyclodecane, bis (aminocyclohexyl) methane, bis (aminocyclohexyl) Isopropylidene, 6,6′-bis (3-aminophenoxy) -3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane, 6,6′-bis (4-aminophenoxy) -3 3,3 ′, 3′-tetramethyl-1,1′-spirobiindane. A diamine component may be used independently and can also be used in combination of multiple types.

The polyimide containing at least one repeating unit represented by the chemical formula (1) can contain other repeating units other than the repeating unit represented by the chemical formula (1).

The tetracarboxylic acid component and diamine component that give other repeating units are not particularly limited, and any other known aliphatic tetracarboxylic acids or known aliphatic diamines can be used. Other tetracarboxylic acid components may be used alone or in combination of two or more. Other diamine components may be used alone or in combination of two or more.

The content of other repeating units other than the repeating unit represented by the formula (1) is preferably 30 mol% or less or less than 30 mol%, more preferably 20 mol% or less, based on all repeating units. More preferably, it is 10 mol% or less.

When schematically showing an example of a method for producing a polyimide film,
(1) A polyimide precursor solution or a polyimide precursor solution composition in which an imidization catalyst, a dehydrating agent, a release aid, inorganic fine particles, etc. are selected and added to a polyimide precursor solution as needed is supported in a film form. A method of obtaining a polyimide film by casting on a body and drying by heating to obtain a self-supporting film, followed by dehydration and desolvation by heating;
(2) A cyclization catalyst and a dehydrating agent are added to the polyimide precursor solution, and further, a polyimide precursor solution composition added by selecting inorganic fine particles as necessary is cast on a support in the form of a film. A method of obtaining a polyimide film by dehydrating and cyclizing and obtaining a self-supporting film by heating and drying as necessary, and then removing the solvent and imidizing it by heating;
(3) When the polyimide is soluble in an organic solvent, a polyimide solution composition added by selecting a mold release aid, inorganic fine particles, etc. is cast on a support in a film form, and partially or by heating and drying A method of obtaining a polyimide film by removing all the solvent and then heating to the maximum heating temperature;
(4) When the polyimide is soluble in an organic solvent, a polyimide solution composition added by selecting a mold release aid, inorganic fine particles and the like is cast on a support in the form of a film, and the solvent is removed by heating. A method of obtaining a polyimide film by heating to the highest heating temperature,
Is mentioned.

Polyimide precursors are: 1) polyamic acid (also called polyamic acid), 2) polyamic acid ester (at least a part of H of the carboxyl group of the polyamic acid is an alkyl group), 3) polyamic acid silyl ester (of polyamic acid At least a part of H of the carboxyl group can be classified as an alkylsilyl group.

These polyimide precursors can be produced from a tetracarboxylic acid component and a diamine component that give the polyimide structure described above.

As an example of a method for producing a polyimide film, for example, a polyimide precursor composition is cast on a substrate, and the polyimide precursor composition on the substrate is, for example, 100 to 500 ° C., preferably 200 to 500 ° C., A method of imidizing the polyimide precursor while removing the solvent by heating at a temperature of about 250 to 450 ° C. is more preferable. In addition, a heating profile is not specifically limited, It can select suitably.

Also, the polyimide precursor composition is cast on a substrate, and preferably dried in a temperature range of 180 ° C. or less to form a polyimide precursor composition film on the substrate, and the resulting polyimide precursor is obtained. For example, 100 to 500 ° C., preferably 200 to 500 ° C., more preferably in a state where the film of the composition is peeled off from the substrate and the edge of the film is fixed or without fixing the edge of the film. The polyimide film can be suitably produced also by heat treatment at a temperature of about 250 to 450 ° C. to imidize the polyimide precursor.

Further, for example, a polyimide solution composition containing polyimide is cast on a substrate, and is heat-treated at a temperature of, for example, about 80 to 500 ° C., preferably 100 to 500 ° C., more preferably about 150 to 450 ° C. By removing, a polyimide film can be suitably produced. In this case, the heating profile is not particularly limited and can be selected as appropriate.

The polyimide film is not particularly limited, but the linear thermal expansion coefficient from 100 ° C. to 250 ° C. is preferably 60 ppm / K or less, more preferably 50 ppm / K or less.

The polyimide film is not particularly limited, but the total light transmittance (average light transmittance at a wavelength of 380 nm to 780 nm) is preferably 68% or more, more preferably 70% or more, more preferably 75% or more, and particularly preferably 80%. % Or more. When used for a display application or the like, if the total light transmittance is low, it is necessary to strengthen the light source, which may cause a problem that energy is applied.

The 5% weight loss temperature that is an index of heat resistance of the polyimide film is not particularly limited, but is preferably 400 ° C. or higher, more preferably 430 ° C. or higher, and further preferably 450 ° C. or higher.

The thickness of the polyimide film is preferably 0.1 μm to 250 μm, more preferably 1 μm to 150 μm, still more preferably 3 μm to 120 μm, and particularly preferably 5 μm to 100 μm, although it depends on the application. When the polyimide film is used for light transmission, if the polyimide film is too thick, the light transmittance may be lowered.

The polyimide film is not particularly limited, but preferably has high solvent resistance. When the solvent resistance is low, when the organic solvent is contained in the coating liquid, the polyimide film surface may melt and whiten, or the film surface may lose its smoothness.

<< Coating layer >>
The coating layer in this invention is a layer formed with the hardened | cured material of the coating composition containing a polyurethane resin and a (meth) acrylate compound.

In this application, the term “(meth) acrylate” refers to both acrylate and methacrylate, and “urethane acrylate” refers to both “urethane acrylate” and “urethane methacrylate” according to common usage. In the present application, “urethane acrylate (urethane (meth) acrylate)” is classified as a (meth) acrylate compound. In the present application, the “polyurethane resin” does not include urethane acrylate (monomer) and a polymer thereof.

First, a coating composition containing a polyurethane resin that gives a cured product layer and a (meth) acrylate compound will be described.

<Coating composition containing polyurethane resin and (meth) acrylate compound>
The material contained in the coating composition containing a polyurethane resin and a (meth) acrylate compound for forming the coating layer will be described below.

a-1. Polyurethane resin A polyurethane resin is produced by a reaction between a polyol and an isocyanate compound, and a structure derived from a polyol and a structure derived from an isocyanate compound are bonded via a urethane structure. Examples of the polyol include polycarbonate polyol, polyester polyol, polyether polyol, polyolefin polyol, acrylic polyol, polydiene polyol, and the like, and preferably selected from polycarbonate polyol, polyester polyol, and polyether polyol. Polyols may be used alone or in combination. In particular, those containing polycarbonate polyol are preferred from the viewpoints of heat resistance, hydrolysis resistance, stain resistance, chemical resistance, and weather resistance. In addition, a polyol having a specific functional group may be used in combination in order to provide a desired function.

Next, as a most preferable example, a polyurethane resin using a polyol component mainly composed of polycarbonate polyol will be described. Other polyurethane resins usable in the present invention will be described as, for example, “other polyol (c)”. It can be obtained by reacting a compound with a polyisocyanate.

a-2. Polyurethane resin based on polycarbonate polyol In the present invention, preferred polyurethane resin is:
At least polycarbonate polyol (a);
If necessary, acidic group-containing polyol (b),
If necessary, other polyol (c),
Reacting with polyisocyanate (d),
In some cases, it is a polyurethane resin obtained by further reacting with a chain extender (B).

The acidic group-containing polyol (b) is preferably used when the polyurethane resin is an aqueous dispersion type (aqueous polyurethane resin dispersion), and is stable even if the composition does not contain a protective colloid, an emulsifier, or a surfactant. Water dispersion can be obtained. In the following description, the water-dispersed polyurethane resin containing the acidic group-containing polyol (b) (sometimes referred to as an aqueous polyurethane resin dispersion) will be mainly described. b) may not be used. Moreover, even if it is a water dispersion type, it is not necessary to use an acidic group containing polyol (b). In this case, for example, an emulsifier, a surfactant or the like may be added. In the composition, the acidic group based on the acidic group-containing polyol (b) may be neutralized with an amine compound or the like. Below, the structural unit contained in a polyurethane resin is mainly demonstrated based on the raw material.

I. Polycarbonate polyol (a)
The polycarbonate polyol (a) used in the present invention is not particularly limited, and is obtained by carbonate bonding of polyol and polyol, and may contain an ester bond or the like in the molecule. The number average molecular weight of the polycarbonate polyol (a) is not particularly limited, and the number average molecular weight is preferably 400 to 8000. When the number average molecular weight is within this range, an appropriate viscosity and good handleability can be easily obtained. Moreover, it is easy to ensure the performance as a soft segment, it is easy to suppress the occurrence of cracks when a coating film is formed using the obtained aqueous polyurethane resin dispersion, and further, the reaction with the isocyanate compound (c) And the urethane prepolymer can be produced efficiently. More preferably, the polycarbonate polyol (a) has a number average molecular weight of 400 to 4000.

The number average molecular weight is the number average molecular weight calculated based on the hydroxyl value measured according to JIS K 1577. Specifically, the hydroxyl value is measured, and is calculated by (56.1 × 1000 × valence) / hydroxyl value (mgKOH / g) by a terminal group quantification method. In the above formula, the valence is the number of hydroxyl groups in one molecule. When the polycarbonate polyol is polycarbonate diol, the valence is 2.

The polycarbonate polyol (a) can be obtained, for example, by reacting one or more polyols with carbonate ester or phosgene. A polycarbonate polyol obtained by reacting one or more polyols with a carbonic acid ester is preferred because it is easy to produce and there is no byproduct of terminal chlorinated products.

The polyol is not particularly limited, and examples thereof include an aliphatic polyol, a polyol having an alicyclic structure, an aromatic polyol, a polyester polyol, and a polyether polyol. In the present specification, the alicyclic structure includes those having a hetero atom such as an oxygen atom or a nitrogen atom in the ring.

The aliphatic polyol is not particularly limited, and examples thereof include aliphatic polyols having 3 to 12 carbon atoms. Specifically, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9 A linear aliphatic diol such as nonanediol; 2-methyl-1,3-propanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-1 Branched aliphatic diols such as 1,9-nonanediol; polyfunctional alcohols having three or more functional groups such as 1,1,1-trimethylolpropane and pentaerythritol.

The polyol having the alicyclic structure is not particularly limited, and examples thereof include a polyol having an alicyclic group having 5 to 12 carbon atoms in the main chain. Specifically, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,3-cyclopentanediol, 1,4-cycloheptanediol, 2,5-bis ( Representative examples are hydroxymethyl) -1,4-dioxane, 2,7-norbornanediol, tetrahydrofuran dimethanol, 1,4-bis (hydroxyethoxy) cyclohexane, tricyclo [5.2.1.0 ^2,6 ] decanedimethanol Examples include diols having an alicyclic structure in the main chain, such as each structural isomer of tricyclodecane dimethanol or a mixture thereof. Of these, 1,4-cyclohexanedimethanol is preferred because of its availability.

The aromatic polyol is not particularly limited, and for example, 1,4-benzenedimethanol, 1,3-benzenedimethanol, 1,2-benzenedimethanol, 4,4′-naphthalenediethanol, 3,4 ′ -Naphthalene diethanol and the like.

The polyester polyol is not particularly limited. For example, a polyester polyol of hydroxycarboxylic acid and diol such as a polyester polyol of 6-hydroxycaproic acid and hexanediol, a dicarboxylic acid such as polyester polyol of adipic acid and hexanediol, and the like. Examples thereof include polyester polyols with diols.

The polyether polyol is not particularly limited, and examples thereof include polyethylene glycol (for example, diethylene glycol, triethylene glycol, tetraethylene glycol, etc.), polyalkylene glycol such as polypropylene glycol, polytetramethylene glycol, and the like.

The carbonate ester is not particularly limited, and examples thereof include aliphatic carbonate esters such as dimethyl carbonate and diethyl carbonate, aromatic carbonate esters such as diphenyl carbonate, and cyclic carbonate esters such as ethylene carbonate. In addition, phosgene or the like capable of producing a polycarbonate polyol can be used. Of these, aliphatic carbonates are preferred and dimethyl carbonate is particularly preferred because of the ease of production of the polycarbonate polyol.

As a method for producing a polycarbonate polyol from the polyol and the carbonate ester, for example, a carbonate ester and a polyol having an excess number of moles relative to the number of moles of the carbonate ester are added to a reactor, and the temperature is 160 to 200 ° C. An example is a method of reacting at a pressure of about 50 mmHg for 5 to 6 hours and further reacting at 200 to 220 ° C. for several hours at a pressure of several mmHg or less. In the reaction, it is preferable to carry out the reaction while extracting by-produced alcohol out of the system. At that time, if the carbonate ester escapes from the system by azeotroping with the by-produced alcohol, an excessive amount of carbonate ester may be added. In the reaction, a catalyst such as titanium tetrabutoxide may be used.

Examples of the polycarbonate polyol (a) include a polycarbonate polyol obtained by reacting one kind of polyol and a carbonate ester, a copolymer polycarbonate polyol obtained by reacting a plurality of kinds of polyol and a carbonate ester, and the like. As such a polycarbonate polyol, for example, a polycarbonate polyol obtained by reacting 1,6-hexanediol and a carbonate, a mixture of 1,6-hexanediol and 1,5-pentanediol, and a carbonate is used. A polycarbonate polyol obtained by reacting a mixture of a polycarbonate polyol obtained by the reaction, 1,6-hexanediol and 1,4-butanediol with a carbonate, 1,4-cyclohexanedimethanol and a carbonate. Examples thereof include polycarbonate diol obtained by reacting a mixture of polycarbonate diol, 1,6-hexanediol and 1,4-cyclohexanedimethanol obtained by reaction with carbonate ester.

From the point that a coating film having excellent drying properties and high hardness is obtained, the polycarbonate polyol (a1) (hereinafter referred to as “polycarbonate polyol (a1)”) having an alicyclic structure in the main chain as the polycarbonate polyol (a). It is preferable to use Moreover, it has the advantage that a coating film excellent in solvent resistance can be obtained. Among them, the polycarbonate polyol (a1) having an alicyclic structure in the main chain preferably has a number average molecular weight of 400 to 5000, more preferably 400 to 3000, and particularly preferably 500 to 2000.

The polycarbonate polyol (a1) having an alicyclic structure in the main chain is, for example, a polycarbonate polyol obtained by reacting a polyol having a alicyclic structure in the main chain with a carbonic ester, or a polyol having an alicyclic structure in the main chain. And other polyols (polyols having no alicyclic structure in the main chain) and carbonated polycarbonates obtained by reacting carbonates. From the viewpoint of dispersibility of the aqueous dispersion, a copolymerized polycarbonate polyol using another polyol in combination is preferable. As other polyols, aliphatic polyols, aromatic polyols, polyester polyols, and polyether polyols can be used, and the above specific examples are applied. Among them, a combination of a polyol having an alicyclic structure in the main chain and an aliphatic polyol is preferable, and a copolymer polycarbonate polyol obtained by using 1,4-cyclohexanedimethanol and 1,6-hexanediol in combination is particularly preferable. .

When the polycarbonate polyol (a1) having an alicyclic structure in the main chain is used, the alicyclic structure content in the polycarbonate polyol (a) is preferably 65% by weight or less. Within this range, the presence of the alicyclic structure makes it easy to obtain a coating film with excellent hardness, while the content of the alicyclic structure becomes too large, and a prepolymer used in the production of an aqueous polyurethane resin dispersion. It is easy to avoid a situation where the viscosity of the resin becomes high and handling becomes difficult. The alicyclic structure content is more preferably 10 to 55% by weight.

Here, the alicyclic structure content refers to the weight ratio of the alicyclic group in the polycarbonate polyol (a). For example, cycloalkane residues such as cyclohexane residues (in the case of 1,4-hexanedimethanol, a portion obtained by removing two hydrogen atoms from cyclohexane) and unsaturated heterocyclic residues such as tetrahydrofuran residues (tetrahydrofuran In the case of dimethanol, it means a value calculated based on the portion obtained by removing two hydrogen atoms from tetrahydrofuran.

Polycarbonate polyol (a) may be used alone or in combination of two or more. For example, only the polycarbonate polyol (a1) having an alicyclic structure in the main chain may be used, or the polycarbonate polyol (a1) having an alicyclic structure in the main chain and another polycarbonate polyol may be used in combination.

Other polycarbonate polyols that can be used in combination with the polycarbonate polyol (a1) having an alicyclic structure in the main chain are not particularly limited, and specifically include polytetramethylene carbonate diol, polypentamethylene carbonate diol, and polytetramethylene carbonate. Aliphatic polycarbonate diols such as xamethylene carbonate diol; Aromatic polycarbonate diols such as poly 1,4-xylylene carbonate diol; Polycarbonate diol which is a reaction product of a plurality of types of aliphatic diols and carbonates; Polycarbonates such as polycarbonate diol, which is a reaction product of aromatic diol and carbonate, polycarbonate diol, which is a reaction product of aliphatic diol, dimer diol and carbonate Diol, and the like. For example, the combined use of a polycarbonate polyol (a1) having an alicyclic structure in the main chain and an aliphatic polycarbonate polyol can be mentioned.

II. Acid group-containing polyol (b)
The acidic group-containing polyol (b) is not particularly limited as long as it contains two or more hydroxyl groups and one or more acidic groups in one molecule. Examples of the acidic group include a carboxy group, a sulfonic acid group, a phosphoric acid group, and a phenolic hydroxyl group. In particular, the acidic group-containing polyol (b) is preferably one containing a compound having two hydroxyl groups and one carboxy group in one molecule. The acidic group-containing polyol (b) may be used alone or in combination of two or more.

Specific examples of the acidic group-containing polyol (b) include dialkanol alkanoic acids including dimethylol alkanoic acids such as 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid; N-bishydroxyethylglycine, N, N-bishydroxyethylalanine, 3,4-dihydroxybutanesulfonic acid, 3,6-dihydroxy-2-toluenesulfonic acid, acidic group-containing polyether polyol, acidic group-containing polyester polyol, etc. Is mentioned. Of these, dialkanol alkanoic acid containing two alkanol groups is preferable from the viewpoint of easy availability, and alkanoic acid having 4 to 12 carbon atoms (dimethylol alkanoic acid) containing two methylol groups is more preferable, and dimethylol. Of the alkanoic acids, 2,2-dimethylolpropionic acid is particularly preferred.

III. Other polyols (c)
In addition to the polycarbonate polyol (a) and the acidic group-containing polyol (b), other polyols (c) (hereinafter also referred to as “other polyols (c)”) may be used. Examples of the other polyol (c) include high molecular polyols such as polymer polyols and low molecular polyols. Examples of the polymer polyol include those having a number average molecular weight of 400 to 4000. The polyol may be a diol or a trihydric or higher polyhydric alcohol. Other polyols may be used alone or in combination of two or more. From the viewpoint that the hardness of the coating film becomes high, a low molecular polyol is preferable, and a low molecular diol is particularly preferable.

The polymer polyol is not particularly limited, and polyester polyol, polyether polyol, acrylic polyol, and polydiene polyol can be suitably used.

The polyester polyol is not particularly limited, and for example, polyethylene adipate polyol, polybutylene adipate polyol, polyethylene butylene adipate polyol, polyhexamethylene isophthalate adipate polyol, polyethylene succinate polyol, polybutylene succinate polyol, polyethylene sebacate polyol And polybutylene sebacate polyol, poly-ε-caprolactone polyol, poly (3-methyl-1,5-pentylene adipate) polyol, polycondensate of 1,6-hexanediol and dimer acid, and the like.

The polyether polyol is not particularly limited, and examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, a random copolymer or a block copolymer of ethylene oxide and propylene oxide, ethylene oxide and butylene oxide, and the like. . Furthermore, a polyether polyester polyol having an ether bond and an ester bond can also be used.

The polydiene polyol is not particularly limited, and examples thereof include polydiene polyols containing units derived from butadiene, isoprene, 1,3-pentadiene, chloroprene, cyclopentadiene, and the like. Specific examples of the polydiene polyol include, for example, hydroxyl-terminated liquid polybutadiene (“Poly bd” manufactured by Idemitsu Kosan Co., Ltd.), bifunctional hydroxyl-terminated liquid polybutadiene (“KRASOL” manufactured by Idemitsu Kosan Co., Ltd.), and hydroxyl-terminated liquid polyisoprene. ("Poly ip" manufactured by Idemitsu Kosan Co., Ltd.), hydroxyl-terminated liquid polyolefin ("Epol" manufactured by Idemitsu Kosan Co., Ltd.), and the like.

The polyacryl polyol is not particularly limited, and examples thereof include acrylic acid esters having active hydrogen such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxybutyl acrylate, or acrylic acid of glycerin. Monoester or methacrylic acid monoester, trimethylolpropane acrylic acid monoester or methacrylic acid monoester alone or in mixture and methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, Acrylic acid esters such as 2-ethylhexyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxypropyl methacrylate, methacrylate Methacrylic acid ester with active hydrogen, such as 4-hydroxybutyl phosphate, or methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, methacrylate-n-butyl, isobutyl methacrylate, methacrylate-n-hexyl, methacrylic acid Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, acrylamide, N-methylol acrylamide, diacetone acrylamide, etc., using a single or mixture selected from the group of methacrylic acid esters such as lauryl It is obtained by polymerizing in the presence or absence of amide and other polymerizable monomers selected from the group of glycidyl methacrylate, styrene, vinyl toluene, vinyl acetate, acrylonitrile, dibutyl fumarate and the like. Poly Acrylic polyols. Examples of the polymerization method include emulsion polymerization, suspension polymerization, dispersion polymerization, solution polymerization and the like. In emulsion polymerization, it can also be polymerized stepwise.

The ratio of the other polyol (c) to the polycarbonate polyol (a) is preferably 40% by weight or less. If it is this range, it will be easy to avoid that the hardness of the coating film obtained falls or manufacture of a polyurethane resin water dispersion becomes difficult. The ratio of the other polyol (c) is more preferably 20% by weight or less.

IV. In the present invention, the total number of hydroxyl equivalents of the polycarbonate polyol (a), the acidic group-containing polyol (b), and any other polyol (c) is preferably 100 to 500. If the number of hydroxyl equivalents is within this range, it is easy to produce an aqueous polyurethane resin dispersion, and a coating film excellent in storage stability and hardness of an excellent aqueous polyurethane resin dispersion is easily obtained. From the viewpoint of the hardness of the coating film, it is preferably 150 to 400, more preferably 180 to 300, and particularly preferably 200 to 270.

The number of hydroxyl equivalents can be calculated by the following formulas (1) and (2).

Number of hydroxyl equivalents of each polyol = molecular weight of each polyol / number of hydroxyl groups of each polyol (1)
Total number of hydroxyl equivalents of polyol = M / total number of moles of polyol (2)
In the above formula (2), M represents [[number of hydroxyl group equivalents of polycarbonate polyol (a) × number of moles of polycarbonate polyol (a)] + [number of hydroxyl group equivalents of acidic group-containing polyol (b) × acidic group-containing polyol ( b) Number of moles] + [number of hydroxyl equivalents of other polyol (c) × number of moles of other polyol (c)]].

V. Polyisocyanate (d)
The polyisocyanate (d) is not particularly limited, and examples thereof include aromatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.

Specific examples of the aromatic polyisocyanate include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, 4,4′-. Diphenylmethane diisocyanate (MDI), 2,4-diphenylmethane diisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4 Examples include '-diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, 4,4', 4 ''-triphenylmethane triisocyanate, m-isocyanatophenylsulfonyl isocyanate, p-isocyanatophenylsulfonyl isocyanate.

Specific examples of the aliphatic polyisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, and 2,2,4-trimethylhexamethylene diisocyanate. Lysine diisocyanate, 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexano Eate.

Specific examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI), 4,4′-dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2 -Isocyanatoethyl) -4-dichlorohexene-1,2-dicarboxylate, 2,5-norbornane diisocyanate, 2,6-norbornane diisocyanate, dimer acid diisocyanate and the like.

These polyisocyanates may be used alone or in combination of two or more.

Although the number of isocyanate groups per molecule of the polyisocyanate is usually two, a polyisocyanate having three or more isocyanato groups such as triphenylmethane triisocyanate is also used as long as the polyurethane resin in the present invention does not gel. can do.

Among the polyisocyanates, 4,4′-diphenylenemethane diisocyanate (MDI), isophorone diisocyanate (IPDI), 4,4′-dicyclohexylmethane diisocyanate (hydrogen) from the viewpoints of control of reactivity, high hardness, imparting strength and the like. Addition MDI) is preferred.

VI. Polyurethane resin or polyurethane prepolymer (A)
The polyurethane resin in this embodiment is a polyurethane resin obtained by reacting at least a polycarbonate polyol (a), an optional acidic group-containing polyol (b), and a polyisocyanate (d), or a polycarbonate polyol (a). And an optional acidic group-containing polyol (b) and a polyisocyanate (d) to obtain a polyurethane prepolymer (A), which is further reacted with a chain extender (B) to obtain a polyurethane Resin. The polyurethane resin or polyurethane prepolymer (A) is obtained by reacting a polycarbonate polyol (a), an optional acidic group-containing polyol (b), an optional other polyol (c), and a polyisocyanate (d). A polyurethane prepolymer obtained by reacting a polycarbonate polyol (a), an optional acidic group-containing polyol (b), an optional other polyol (c), and the polyisocyanate (d). It may be a polyurethane resin obtained by obtaining (A) and further reacting it with a chain extender (B). When the polyurethane prepolymer (A) and the chain extender (B) are reacted to obtain a polyurethane resin, the reaction temperature between the polyurethane prepolymer (A) and the chain extender (B) is: For example, it is 0 to 80 ° C., preferably 0 to 60 ° C.

When obtaining the polyurethane resin or polyurethane prepolymer (A), when the total amount of the polycarbonate polyol (a), any acidic group-containing polyol (b) and any other polyol (c) is 100 parts by weight. The ratio of the polycarbonate polyol (a) is preferably 50 to 95 parts by weight, more preferably 70 to 92 parts by weight, particularly preferably 80 to 90 parts by weight, and the ratio of the acidic group-containing polyol (b) is preferably Is 5 to 25 parts by weight, more preferably 10 to 20 parts by weight, particularly preferably 12 to 18 parts by weight, and the proportion of the other polyol (c) is preferably 0 to 40 parts by weight, more preferably 0 to 30 parts by weight, particularly preferably 0 to 20 parts by weight. If the ratio of the said polycarbonate polyol (a) is said range, it will be suppressed that the hardness of a coating film becomes low and favorable film forming property will be easy to be obtained. When the ratio of the acidic group-containing polyol (b) is in the above range, the resulting aqueous polyurethane resin has good dispersibility in an aqueous medium, and sufficient water resistance of the coating film is easily obtained. If the proportion of the other polyol (c) is within the above range, the proportion of the polycarbonate polyol (a) in the total polyol component is relatively too small, or the proportion of the acidic group-containing polyol compound (b). Therefore, it is easy to obtain good hardness of the coating film and dispersibility of the aqueous polyurethane resin.

When obtaining the polyurethane resin or polyurethane prepolymer (A), a polyol component comprising the polycarbonate polyol (a) and the acidic group-containing polyol (b), or the polycarbonate polyol (a) and the acidic group. The ratio of the number of moles of isocyanate groups of the polyisocyanate (d) to the number of moles of all hydroxyl groups in the polyol component consisting of the polyol (b) and other polyols (c) is 1.01 to 2.5. preferable. If it is in this range, the number of moles of hydroxyl groups of the polyol component is too large, so that the polyurethane prepolymer (A) having no isocyanate group at the molecular end increases and there are many molecules that do not react with the chain extender (B). Thus, it is easy to avoid the problem that the strength of the coating film obtained by applying the aqueous polyurethane resin dispersion is reduced, and the number of hydroxyl groups of the polyol component is too small. d) Remains in the reaction system in a large amount and reacts with the chain extender or reacts with water to cause molecular elongation, resulting in unevenness in the coating film obtained by applying the aqueous polyurethane resin dispersion. Is easy to avoid. The ratio of the number of moles of isocyanate groups of the polyisocyanate (d) to the number of moles of all hydroxyl groups in the polyol component is preferably 1.2 to 2.2, particularly preferably 1.2 to 2.0.

In the case of obtaining the polyurethane resin or polyurethane prepolymer (A), a polyol component comprising the polycarbonate polyol (a), the acidic group-containing polyol (b), and, if necessary, other polyol (c), In the reaction with the polyisocyanate (d), (a), (b) and (c) may be reacted with (d) in any order, or a plurality of types may be mixed and reacted with (d).

In the present invention, the acid value of the polyurethane resin or polyurethane prepolymer (A) is preferably 10 to 55 mgKOH / g. If it is this range, it will be easy to ensure the dispersibility to an aqueous medium and the water resistance of a coating film. The acid value is more preferably 14 to 42 mgKOH / g, still more preferably 18 to 35 mgKOH / g acid value.

VII. Chain extender (B)
The chain extender (B) in the present invention has reactivity with the isocyanate group of the polyurethane prepolymer (A). Examples of chain extenders include ethylenediamine, 1,4-tetramethylenediamine, 2-methyl-1,5-pentanediamine, 1,4-butanediamine, 1,6-hexamethylenediamine, 1,4-hexamethylene. Diamine, 3-aminomethyl-3,5,5-trimethylcyclohexylamine, 1,3-bis (aminomethyl) cyclohexane, xylylenediamine, piperazine, 2,5-dimethylpiperazine, hydrazine, adipoyl dihydrazide, diethylenetriamine, Examples include amine compounds such as triethylenetetramine, diol compounds such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol, polyalkylene glycols typified by polyethylene glycol, water and the like. Like It can be mentioned primary diamine compound. These may be used alone or in combination of two or more.

The addition amount of the chain extender (B) is preferably equal to or less than the equivalent of the isocyanate group serving as a chain extension starting point in the polyurethane prepolymer (A) to be obtained, and more preferably 0.7 to 0.99 of the isocyanate group. Is equivalent. When the chain extender (B) is added in excess of the equivalent of the isocyanato group, the molecular weight of the chain-extended polyurethane polymer (A) is lowered, and the obtained aqueous polyurethane resin dispersion is applied. The strength of the coated film decreases. The chain extender (B) may be added after the dispersion of the polyurethane prepolymer in water, or may be added during the dispersion. Chain extension can also be carried out with water. In this case, water as a dispersion medium also serves as a chain extender.

a-3. (Meth) acrylate compounds (Meth) acrylate compounds that can be used in the present invention include (meth) acrylate compounds of monomers, polyurethane (meth) acrylate compounds, polyester (meth) acrylate compounds, polyalkylene (meth) acrylate compounds Compounds and the like. In this specification, (meth) acrylate refers to acrylate or / and methacrylate.

Examples of the monomer (meth) acrylate compound include mono (meth) acrylate, di (meth) acrylate, tri (meth) acrylate, tetra (meth) acrylate, penta (meth) acrylate, and hexa (meth) acrylate. (Meth) acrylate and poly (meth) acrylate can be used.

Examples of the mono (meth) acrylate include acryloylmorpholine, 2-ethylhexyl (meth) acrylate, styrene, methyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dodecyl (meth) acrylate, cyclohexyl (meth) acrylate, Dicyclopentenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, N-vinyl-2-pyrrolidone, 2-methacryloyl Oxyethyl isocyanate, methacryloyl isocyanate, 3-isopropenyl-α, α-dimethylbenzyl isocyanate, 3-isocyanatopropyltrimethoxysilane , P-toluenesulfonyl isocyanate and the like.

Examples of the di (meth) acrylate include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1, Alkylene glycol di (meth) acrylates such as 6-hexanediol di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, bisphenol A di (meth) acrylate; polyethylene glycol di (meth) acrylate, polypropylene glycol di ( Polyether di (meth) acrylate such as meth) acrylate; bisphenol A ethylene oxide modified di (meth) acrylate, bisphenol A propylene oxide modified di (meth) acrylate Alkylene oxide modified di (meth) acrylates such as neopentyl glycol ethylene oxide modified di (meth) acrylate and neopentyl glycol propylene oxide modified di (meth) acrylate; 1,6-hexanediol epoxy di (meth) acrylate, neopentyl glycol Epoxy di (meth) acrylate, bisphenol A epoxy di (meth) acrylate, bisphenol A propylene oxide modified epoxy di (meth) acrylate, phthalic acid epoxy di (meth) acrylate, polyethylene glycol epoxy di (meth) acrylate, polypropylene glycol epoxy di (meth) And epoxy di (meth) acrylates such as acrylate.

Examples of the tri (meth) acrylate include trimethylolpropane triacrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate. Can be mentioned.

Examples of the tetra (meth) acrylate include pentaerythritol tetra (meth) acrylate and ditrimethylolpropane tetra (meth) acrylate.

Examples of the penta (meth) acrylate include dipentaerythritol penta (meth) acrylate.

Examples of the hexa (meth) acrylate include dipentaerythritol hexa (meth) acrylate.

Among these (meth) acrylate compounds of these monomers, from the viewpoint of hardness, poly (poly (meth) acrylate such as di (meth) acrylate, tri (meth) acrylate, tetra (meth) acrylate, penta (meth) acrylate, hexa (meth) acrylate, etc. (Meth) acrylate is preferred. This is because by having a plurality of (meth) acryloyl groups in the molecule, it is easier to increase the molecular weight than in the case of mono (meth) acrylates.

Also, known polymers can be used as the (meth) acrylate compound. In particular, a compound having a polyalkylene glycol structure in the molecule is preferable, and a compound having a polyalkylene glycol structure represented by the following general formula (1) in the molecule is particularly preferable. Since the (meth) acrylate compound of the polymers has a polyalkylene glycol structure in the molecule, it becomes easier to disperse in an aqueous medium, and the storage stability of the resulting aqueous polyurethane dispersion is improved. In addition, when the polyalkylene glycol structure is a structure represented by the following general formula (1), since the storage stability of the (meth) acrylate compound itself of the polymers is high and the dispersibility in an aqueous medium is also high, preferable.

(In the formula, R represents a linear or branched alkyl group having 2 to 5 carbon atoms which may have a substituent, and n represents an integer of 1 to 10.)

Examples of the (meth) acrylate compound of the polymer that is a compound having a polyalkylene glycol structure in the molecule include di (meth) acrylate, tri (meth) acrylate, tetra (meth) acrylate in addition to mono (meth) acrylate. And poly (meth) acrylates such as acrylate.

Moreover, a urethane acrylate compound can also be mentioned as a (meth) acrylate compound of polymers. The urethane acrylate compound is a compound having a urethane skeleton and at least one (meth) acryloyl group in the molecule. That is, it has a structure in which a (meth) acryloyl group is bonded to a terminal (including a side chain) of a urethane polymer (including an oligomer). The number of (meth) acryloyl groups is preferably 2-8. The (meth) acryloyl group is a group represented by CH ₂ ═C (R ⁰¹ ) C (═O) — (where R ⁰¹ is H or CH ₃ ).

The urethane skeleton part has the same structure as that of the above-described polyurethane resin, that is, a structure obtained by a reaction between a polyol and a polyisocyanate compound. The (meth) acryloyl group is generally introduced by reacting a hydroxyl group-containing (meth) acrylic compound with an isocyanate group. After reacting a polyol and an isocyanate compound, it can be produced by further reacting a hydroxyl group-containing (meth) acrylic compound, or reacting a polyol, an isocyanate compound and a hydroxyl group-containing (meth) acrylic compound simultaneously.

Examples of the polyol as a raw material for the urethane acrylate compound include polycarbonate polyol, polyester polyol, polyether polyol, polyolefin polyol, acrylic polyol, and polydiene polyol. These compounds may be used alone or in combination. In addition, a polyol having a specific functional group may be used in combination in order to provide a desired function.

Preferred polyols are polycarbonate polyols, polyester polyols, polyether polyols, and combinations thereof, with polycarbonate polyols being particularly preferred. Among these, those described in the section of polycarbonate polyol (a) are preferable. The polyester polyol and polyether polyol have been described in the section of other polyol (c).

Further, as the polyisocyanate compound as a raw material of the urethane acrylate compound, those described in the section of polyisocyanate (d) can be used.

As the hydroxyl group-containing (meth) acrylic compound, a hydroxyl group-containing (meth) acrylate is preferable. Specifically, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxybutyl (Meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, di (meth) acrylate of tris (hydroxyethyl) isocyanuric acid, pentaerythritol tri (meth) acrylate and the like. The urethane acrylate compound is composed of molecules based on the above raw material compounds.

Examples of the mono (meth) acrylate include polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polyethylene glycol-polypropylene glycol mono (meth) acrylate, and poly (ethylene glycol-tetramethylene glycol) mono (meth). ) Acrylate, poly (propylene glycol-tetramethylene glycol) mono (meth) acrylate, methoxy polyethylene glycol mono (meth) acrylate, octoxy polyethylene glycol-polypropylene glycol mono (meth) acrylate, lauroxy polyethylene glycol mono (meth) acrylate, Stearoxy polyethylene glycol mono (meth) acrylate, nonylphenoxy polyethylene group Call mono (meth) acrylate, nonylphenoxy polypropylene glycol polyethylene glycol mono (meth) acrylate.

Examples of the poly (meth) acrylate include polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polyethylene glycol-polypropylene glycol di (meth) acrylate, and poly (ethylene glycol-tetramethylene glycol) di (meth). ) Acrylate, poly (propylene glycol-tetramethylene glycol) di (meth) acrylate, methoxypolyethylene glycol di (meth) acrylate, octoxypolyethylene glycol-polypropylene glycol di (meth) acrylate, lauroxy polyethylene glycol di (meth) acrylate, Stearoxy polyethylene glycol di (meth) acrylate, nonylphenoxy polyethylene glycol di (meth) Alkylene oxide modified trimethylol such as acrylate, urethane di (meth) acrylate, nonylphenoxy polypropylene glycol polyethylene glycol di (meth) acrylate, ethylene oxide (6 mol) modified trimethylolpropane triacrylate (Laromar (registered trademark) LR8863 manufactured by BASF) Examples include propane triacrylate (Laromer (registered trademark) PO33F manufactured by BASF), ethylene oxide (3 mol) -modified pentaerythritol tetra (meth) acrylate, and the like.

Further, as the (meth) acrylate compound, a commercially available product may be used as it is. As a commercial item, each grade of the Blemmer series by Nippon Oil & Fats, Lamarer (registered trademark) by BASF, etc. are mentioned, for example.

As the (meth) acrylate of the polymer other than the compound having the polyalkylene glycol structure, for example, an acrylic polymer having a polymerizable unsaturated bond at the molecular end can be used.

Examples of the acrylic polymer having a polymerizable unsaturated bond at the molecular end include, for example, polybutyl acrylate having a polymerizable double bond at the molecular end (“Act Flow BGV-100T” manufactured by Soken Chemical Co., Ltd.) Examples thereof include polybutyl acrylate having a polymerizable double bond at the terminal (“Act Flow” manufactured by Soken Chemical Co., Ltd.)

(Meth) acrylate compounds may be used alone or in combination of two or more.

The proportion of the (meth) acrylate compound is, for example, 2% by weight or more, preferably 3% by weight or more, more preferably 5% by weight or more, out of 100% by weight of the solid content (solid content based on the resin component) in the coating composition. More preferably, it is 10% by weight or more, and usually 80% by weight or less, for example 70% by weight or less, preferably 60% by weight or less, more preferably 50% by weight or less, even more preferably 40% by weight or less, Preferably it is 30 weight% or less. If the proportion of the (meth) acrylate compound is too small, the solvent resistance decreases, and if it is too large, the adhesion with the polyimide film decreases. If it is this range, it will be excellent in the drying property of a coating film, and the hardness of a high coating film will be easy to be obtained, and also in the case of an aqueous polyurethane resin dispersion, it is easy to make storage stability favorable.

The (meth) acrylic equivalent of the (meth) acrylate compound is preferably 90 to 300. If it is this range, the storage stability of a water-based polyurethane resin dispersion is favorable, and the light resistance and hardness of a coating film are easy to be obtained. The (meth) acrylic equivalent of the (meth) acrylate compound is more preferably 90 to 150. When a plurality of (meth) acrylate compounds are used in combination, the sum of (meth) acrylic equivalents of each (meth) acrylate compound multiplied by the ratio of each (meth) acrylate compound in all (meth) acrylate compounds is The (meth) acrylic equivalent of the (meth) acrylate compound. Moreover, in this specification, (meth) acryl equivalent means a methacryl equivalent and an acrylic equivalent, and is represented by a following formula.
(Meth) acrylic equivalent = (molecular weight of (meth) acrylate compound) / (number of (meth) acryloyl groups in one molecule)

In the present invention, it is preferable to use a bifunctional (meth) acrylate compound (C1) and a trifunctional or higher functional (meth) acrylate compound (C2) as the (meth) acrylate compound. Here, the “bifunctional (meth) acrylate compound” represents a compound having two (meth) acryloyl groups in one molecule, and the “trifunctional or more (meth) acrylate compound” represents one molecule. A compound having three or more (meth) acryloyl groups is represented.

(Bifunctional (meth) acrylate compound (C1))
In the present invention, the bifunctional (meth) acrylate compound (C1) is not particularly limited, and for example, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, Alkylene glycol di (meth) acrylates such as 4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, bisphenol A di (meth) acrylate; Polyether di (meth) acrylates such as polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate; bisphenol A ethylene oxide modified di (meth) acrylate, bisphenol A propylene Alkylene oxide modified di (meth) acrylates such as oxide modified di (meth) acrylate, neopentyl glycol ethylene oxide modified di (meth) acrylate, neopentyl glycol propylene oxide modified di (meth) acrylate; 1,6-hexanediol epoxy di (Meth) acrylate, neopentyl glycol epoxy di (meth) acrylate, bisphenol A epoxy di (meth) acrylate, bisphenol A propylene oxide modified epoxy di (meth) acrylate, phthalic acid epoxy di (meth) acrylate, polyethylene glycol epoxy di (meth) acrylate , Epoxy di (meth) acrylates such as polypropylene glycol epoxy di (meth) acrylate, urethane di (meth) acrylate Over doors and the like. Among the bifunctional (meth) acrylate compounds, alkylene glycol di (meth) acrylate and polyether diene are easily available, have a high consumption ratio of acryloyl groups by light irradiation, and are excellent in light resistance of the resulting coating film. (Meth) acrylate is preferred, polyether di (meth) acrylate is more preferred, and polypropylene glycol di (meth) acrylate is particularly preferred. These bifunctional (meth) acrylate compounds may be used alone or in combination.

Examples of the polypropylene glycol di (meth) acrylate include dipropylene glycol diacrylate (number average molecular weight 242; for example, APG-100 manufactured by Shin-Nakamura Chemical Co., Ltd., DPGDA manufactured by Daicel Ornex Co., Ltd.), tripropylene glycol diacrylate (number Average molecular weight 300, for example, Aronix M-220 manufactured by Toagosei Co., Ltd., APG-200 manufactured by Shin-Nakamura Chemical Co., Ltd., TPGDA manufactured by Daicel Ornex Co., Ltd., etc. M-225, Shin-Nakamura Chemical Co., Ltd. APG-400, etc., Hitachi Chemical Industries FA-P240A), undecapropylene glycol diacrylate (number-average molecular weight 808, for example, Aronix M-270 manufactured by Toagosei Co., Ltd., Shin-Nakamura Chemical) APG-700 manufactured by Kogyo Co., Ltd., FA-P270A manufactured by Hitachi Chemical Co., Ltd.) and the like. The number average molecular weight of the polypropylene glycol di (meth) acrylate is not particularly limited, but is preferably 500 or less from the viewpoint of obtaining a hard coating film.

Among them, dipropylene glycol diacrylate and tripropylene glycol diacrylate are preferable from the viewpoint of stability of the polyurethane resin aqueous dispersion, and tripropylene glycol diacrylate is more preferable from the viewpoint of skin irritation of the polyurethane resin aqueous dispersion.

(Trifunctional or higher (meth) acrylate compound (C2))
Examples of the tri- or higher functional (meth) acrylate compound (C2) include trimethylolpropane triacrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, and pentaerythritol. Tri (meth) acrylate compounds such as tri (meth) acrylate and tris (acryloyloxyethyl) isocyanurate; Tetra (meth) acrylate compounds such as pentaerythritol tetra (meth) acrylate; Dipentaerythritol penta (meth) acrylate and the like Penta (meth) acrylate compounds; hexa (meth) acrylate compounds such as dipentaerythritol hexa (meth) acrylate and the like. Among the tri- or higher functional (meth) acrylates, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate are preferable from the viewpoint of stability of the polyurethane resin aqueous dispersion. From the viewpoint of consumption of acryloyl groups during ultraviolet irradiation, trimethylolpropane triacrylate, pentaerythritol triacrylate, and pentaerythritol tetraacrylate are more preferable. These trifunctional or higher functional (meth) acrylate compounds may be used alone or in combination of two or more. For example, combined use of a tri (meth) acrylate compound and a tetra (meth) acrylate compound can be mentioned.

The tri- or higher functional (meth) acrylate compound (C2) is tri-functional or higher without an average of two or more ether bonds in the molecule because of its availability and high hardness of the resulting coating film. (Meth) acrylate compound is preferable, trifunctional (meth) acrylate compound having no ether bond in the molecule and / or tetrafunctional (meth) acrylate compound having no ether bond in the molecule is more preferable, Tri (meth) acrylate having no ether bond in the molecule is particularly preferred. Among the triol triacrylates, trimethylolpropane triacrylate and / or trimethylolpropane trimethacrylate is preferable because of its availability.

When the bifunctional (meth) acrylate compound (C1) and the trifunctional or higher (meth) acrylate compound (C2) are used in combination, the respective ratios are preferably 5:95 to 95: 5. If it is this range, the coating film excellent in hardness and light resistance will be easy to be obtained. Each ratio is more preferably 90:10 to 20:80, and still more preferably 80:20 to 40:60.

a-4. Other components included in the coating composition The coating composition containing the polyurethane resin and the (meth) acrylate compound may include a dispersion medium and / or a solvent. When the polyurethane resin is a water dispersion type, examples of the dispersion medium include water and a mixed solvent of water and a hydrophilic organic solvent.

Examples of hydrophilic organic solvents include lower monohydric alcohols such as methanol, ethanol and propanol; polyhydric alcohols such as ethylene glycol and glycerin; Hydrophilic organic solvents and the like. The amount of the hydrophilic organic solvent in the aqueous medium is preferably 0 to 20% by weight.

When the polyurethane resin is a solvent type, an aromatic solvent such as toluene or xylene, an ester solvent such as ethyl acetate, a petroleum solvent such as mineral spirit, or the like can be used as the solvent.

Furthermore, a polymerization initiator may be added to the coating composition. For example, a thermal polymerization initiator or a photopolymerization initiator can be added. Although it depends on the application, it is preferable to add a photopolymerization initiator to form a photo-curing type because a cured coating layer can be obtained at a relatively low temperature. Moreover, although the yellowness of a polyimide film may be able to be improved by formation of a coating layer, the thermosetting type (which does not need to contain a thermal polymerization initiator) is particularly preferable because it has an effect of lowering the yellowness.

Commonly used thermal polymerization initiators can be used, such as diacyl peroxides, ketone peroxides, hydroperoxides, dialkyl peroxides, peroxyesters, azo compounds, persulfates, etc. Can be mentioned. These may be used alone or in combination of two or more.

As the photopolymerization initiator, those generally used can be used, for example, photocleavage type and / or hydrogen abstraction type that can be easily cleaved to form two radicals by ultraviolet irradiation, or a mixture thereof. can do. Examples of these compounds include acetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, benzophenone, 2-chlorobenzophenone, p, p′-bisdiethylaminobenzophenone, benzoin ethyl ether, benzoin n-propyl ether, Benzoin isopropyl ether, benzoin isobutyl ether, benzoin n-butyl ether, benzoin dimethyl ketal, thioxanthone, p-isopropyl-α-hydroxyisobutylphenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2- Methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-hydroxy-2-methyl-1-phenyl Propan-1-one, 2,4,6, - trimethyl benzophenone, 4-methylbenzophenone, 2,2-dimethoxy-1,2-diphenyl-ethanone, and the like. Preferably, hydroxycyclohexyl phenyl ketone is used.

If necessary, additives such as thickeners, photosensitizers, curing catalysts, ultraviolet absorbers, light stabilizers, antifoaming agents, plasticizers, surface conditioners, anti-settling agents may be added. it can. The said additive may be used independently and may use multiple types together. In the case of a water-dispersed composition, it is preferable that substantially no protective colloid, emulsifier, or surfactant is contained from the viewpoint of the hardness and chemical resistance of the resulting coating film.

Other resins can also be added to the coating composition of the present invention. Examples of other resins include polyester resins, acrylic resins, polyether resins, polycarbonate resins, polyurethane resins, epoxy resins, alkyd resins, and polyolefin resins. These may be used alone or in combination of two or more. In the case of the water-dispersed composition, the other resin preferably has one or more hydrophilic groups. Examples of the hydrophilic group include a hydroxyl group, a carboxy group, a sulfonic acid group, and a polyethylene glycol group. When other resins are added, they are preferably used in an amount of 10% by weight or less (including 0% by weight) of the total resin components.

a-5. Polyurethane resin based on polycarbonate polyol, or method for producing coating composition containing polyurethane resin and (meth) acrylate compound Polyurethane resin based on polycarbonate polyol, or production of coating composition containing polyurethane resin and (meth) acrylate compound For example, it can manufacture according to the method described in WO2011 / 010719.

For example, a step of obtaining a polyurethane prepolymer (A) by reacting a polycarbonate polyol (a), an acidic group-containing polyol (b) if necessary, another polyol (c) if necessary, and a polyisocyanate (d); ,
A step (β) of neutralizing acidic groups of the polyurethane prepolymer (A);
A step (γ) of dispersing the polyurethane prepolymer (A) and the (meth) acrylate compound in an aqueous medium;
Produced by reacting the polyurethane prepolymer (A) with a chain extender (B) having reactivity with the isocyanate group of the polyurethane prepolymer (A) to obtain an aqueous polyurethane resin (δ). can do.

Examples of the acidic group neutralizing agent that can be used in the step (β) of neutralizing the acidic group of the polyurethane prepolymer (A) include trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N -Organic amines such as phenyldiethanolamine, dimethylethanolamine, diethylethanolamine, N-methylmorpholine, pyridine and the like can be used.

<< Formation of coating layer >>
Manufacture of the polyimide film laminated body of this invention can be implemented by apply | coating the coating composition containing the above-mentioned polyurethane resin and the (meth) acrylate compound to the above-mentioned polyimide film, and making it harden | cure.

The coating method is not particularly limited, and known methods such as die coating, screen printing, and spin coating can be used.

The thickness of the coating layer after curing is not particularly limited, but is usually about 5 nm to 20 μm. Particularly preferably, it is 10 μm or less, more preferably 5 μm or less, further preferably less than 5 μm, still more preferably 4 μm or less, and most preferably 3 μm or less. Moreover, 10 nm or more is more preferable. Therefore, the coating thickness of the coating liquid is determined so that the thickness becomes such after curing. In particular, as shown in the examples, when the thickness of the coating layer is increased, the surface hardness may be insufficient when a hard coat layer is formed thereon as a surface layer.

After application, if necessary, dry to cure the coating composition film. Curing is performed by heat treatment or light irradiation.

<< Polyimide film laminate >>
As mentioned above, the polyimide film laminated body of this invention can be manufactured by forming a coating layer on a polyimide film.

In a preferred embodiment of the present invention, since the coating layer is excellent in adhesion and solvent resistance, a surface layer can be formed by applying a solvent-containing material thereon. For example, when a hard coat layer is formed by applying a hard coat material, the scratch resistance of the polyimide surface can be improved. The hardness of the surface layer is preferably 2H or more in terms of pencil hardness.

Therefore, one embodiment of the present invention relates to a laminate (with a surface layer) comprising a polyimide film, a coating layer, and a surface layer. As the surface layer, as described above, a hard coat layer capable of improving the scratch resistance of the polyimide surface is preferable. A laminate (with a surface layer) having a hard coat layer has a surface hardness of 2H or more in pencil hardness.

The hard coat layer can be formed of an organic material (cured resin), an inorganic material, an organic-inorganic hybrid type material (such as a cured resin containing an inorganic material), or the like. The formation method can be selected according to each material. From the viewpoint of applicability to mass production and cost, for example, it is preferably formed by a coating method using a curable resin composition described below.

The curable resin composition contains at least a curable resin component and is cured by light or heat to become a cured product (polymerized product, crosslinked product). The curable resin composition contains a curing agent (crosslinking agent, light or thermal polymerization initiator, co-reactant) as necessary. It is also preferable that the curable resin composition contains an inorganic filler. In addition to the curable resin, a solvent-drying resin may be included. If necessary, a solvent may be included. In the present specification, the curable resin composition is a liquid composition in which each component is mixed, a liquid film form that has been applied, a film form in which the solvent has been removed but has not been finally cured, etc. Includes items that have not been processed.

Examples of the curable resin having photocurability include those having at least one photopolymerizable functional group. In the present specification, the “photopolymerizable functional group” is a functional group capable of undergoing a polymerization reaction by light irradiation. Examples of the photopolymerizable functional group include ethylenic double bonds such as a (meth) acryloyl group, a vinyl group, and an allyl group. Specific examples of the photocurable resin component include polyfunctional (meth) acrylate monomers, (meth) acrylate prepolymers, and photocurable polymers. The polyfunctional (meth) acrylate monomer and the (meth) acrylate prepolymer may be used alone or in combination. The light irradiated when the curable resin composition (in the case of photocuring) is cured includes visible light and ionizing radiation such as ultraviolet rays, X-rays, electron beams, α rays, β rays, and γ rays. Is mentioned.

The thermosetting resin having thermosetting property has at least one thermosetting functional group. When a thermosetting resin is used as the curable resin component, usable thermosetting resins include epoxy resins, polyimide resins, phenol resins, silicone resins, cyanate resins, bismaleimide triazine resins, and allylation. Examples include polyphenylene ether resin (thermosetting PPE), formaldehyde resin, unsaturated polyester, and copolymers thereof.

Examples of inorganic fillers include powders such as silica, alumina, boehmite, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, boron nitride, and zirconium oxide, beads formed by spheroidizing these, single crystal fibers, and glass fibers. These can be used alone or in admixture of two or more. Among these, silica, alumina, boehmite, titanium oxide, zirconium oxide and the like are preferable, and silica, titanium oxide and zirconium oxide are more preferable. The inorganic filler is preferably surface-modified. An example of such a particularly preferred inorganic filler is reactive silica.

In this specification, “reactive silica” is silica fine particles whose surface is modified with an organic compound having a photocurable unsaturated group. The silica fine particles (reactive silica) surface-modified with the organic compound having a photocurable unsaturated group are usually silica fine particles having an average particle size of about 0.5 to 500 nm, preferably an average particle size of 1 to 200 nm. It can be obtained by reacting a silanol group on the surface with a photocurable unsaturated group-containing organic compound having a functional group capable of reacting with the silanol group and a (meth) acryloyl group.

The average particle size of the inorganic filler used in the present embodiment is preferably 1 to 200 nm, particularly preferably 10 to 200 nm, and further preferably 20 to 200 nm. When the average particle size of the inorganic filler is 1 nm or more, the hard coat layer obtained by curing the curable resin composition has higher surface hardness. Further, when the average particle size of the inorganic filler is 200 nm or less, light scattering hardly occurs in the obtained hard coat layer, and the transparency of the hard coat layer becomes high.

The content of the inorganic filler in the hard coat layer of the present embodiment is preferably 10 to 85% by volume, particularly preferably 20 to 80% by volume, and 40 to 70% by volume with respect to the hard coat layer. More preferably, it is most preferably 45 to 65% by volume. When the content of the inorganic filler is 10% by volume or more, the surface hardness imparted to the hard coat layer becomes higher. On the other hand, formation of a hard-coat layer becomes easy because content of an inorganic filler is 85 volume% or less.

The curable resin composition may contain various additives in addition to the components described above. Examples of the various additives include ultraviolet absorbers, antioxidants, light stabilizers, antistatic agents, silane coupling agents, anti-aging agents, thermal polymerization inhibitors, colorants, surfactants, storage stabilizers, plasticizers. Agents, lubricants, antifoaming agents, organic fillers, wettability improvers, coating surface improvers and the like.

In order to produce a laminate comprising a polyimide film, a coating layer and a surface layer (with a surface layer), a curable resin composition is applied on the coating layer of the polyimide film / coating layer laminate, and if necessary, the solvent is dried. Then, the hard coat layer formed of a cured product is obtained by light irradiation or heating.

The thickness of the hard coat layer is, for example, 1 to 50 μm, preferably 5 to 40 μm. When the thickness of the hard coat layer is 1 μm or more, sufficient surface hardness is imparted to the hard coat laminate according to this embodiment. On the other hand, when the thickness of the hard coat layer is 50 μm or less, the hard coat laminate is excellent in bending resistance and easy to handle, and the hard coat laminate becomes unnecessarily thick and the manufacturing cost increases. Can be prevented.

Hereinafter, the present invention will be further described with reference to examples and comparative examples. In addition, this invention is not limited to a following example.

In the following examples, evaluation was performed by the following method.

[Total light transmittance]
Using a UV-visible spectrophotometer / V-650DS (manufactured by JASCO), the light transmittance at the total light transmittance (average transmittance from 380 nm to 780 nm) of the polyimide film was measured.

[YI (yellowness)]
Measurements were performed according to ASTM E313.

[Tensile modulus, elongation at break]
The polyimide film is punched into IEC-540 (S) standard dumbbell shape to make a test piece (width: 4 mm), and the initial tensile elastic modulus is 30 mm between chucks with a tensile speed of 2 mm / min using TENILON manufactured by ORIENTEC. The elongation at break was measured.

[Linear thermal expansion coefficient (CTE)]
A polyimide film is cut into a strip of 4 mm in width to make a test piece, and TMA / SS6100 (manufactured by SII Nano Technology Co., Ltd.) is used. The temperature rose. The linear thermal expansion coefficient from 100 ° C. to 250 ° C. was determined from the obtained TMA curve.

[5% weight loss temperature]
Using a polyimide film as a test piece, the temperature was increased from 25 ° C. to 600 ° C. at a temperature increase rate of 10 ° C./min in a nitrogen stream using a thermogravimetry apparatus (Q5000IR) manufactured by TA Instruments. From the obtained weight curve, a 5% weight loss temperature was determined.

[Solvent resistance test]
About 3 cm square polyimide film was immersed in methyl ethyl ketone for 1 hour, taken out and wiped with Kimwipe, and then the change was visually confirmed. The case where there was no change was evaluated as ◯, and the case where changes such as whitening, film surface disturbance, and swelling were observed was evaluated as x.

The abbreviations, purity, etc. of the raw materials used in the following examples are as follows.

[Diamine component]
m-TD: 2,2′-dimethyl-4,4′-diaminobiphenyl [purity: 99.85% (GC analysis)]
tra-DACH: trans-1,4-diaminocyclohexane TFMB: 2,2′-bis (trifluoromethyl) benzidine [Purity: 99.83% (GC analysis)]
4,4′-ODA: 4,4′-oxydianiline [Purity: 99.9% (GC analysis)]
[Tetracarboxylic acid component]
CpODA: norbornane-2-spiro-α-cyclopentanone-α′-spiro-2 ″ -norbornane-5,5 ″, 6,6 ″ -tetracarboxylic dianhydride CBDA: 1,2,3 , 4-Cyclobutanetetracarboxylic dianhydride [Purity: 99.9% (GC analysis)]
s-BPDA: 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride [purity 99.9% (H-NMR analysis)]
a-BPDA: 2,3 ′, 3,4′-biphenyltetracarboxylic dianhydride [purity 99.9% (H-NMR analysis)]
6FDA: 4,4 ′-(2,2-hexafluoroisopropylene) diphthalic dianhydride [purity 99.77% (H-NMR analysis)]
PMDA-HS: 1R, 2S, 4S, 5R-cyclohexanetetracarboxylic dianhydride [purity: 99.9% (GC analysis)]
[solvent]
DMAc: N, N-dimethylacetamide water: pure water

The structural formulas of the tetracarboxylic acid component and the diamine component are shown below.

<Evaluation of polyimide film laminate>
(Cross cut test_ASTM D3359-02)
Cuts that penetrated the coating layer and reached the polyimide film surface were provided in a grid pattern (1 mm interval, 100 squares), and after the adhesive tape was attached, the adhesive tape was peeled off to evaluate the peeling.

Evaluation criteria:
Evaluation was performed according to ASTM D3359-02.

(Solvent resistance test)
About 1 ml of methyl ethyl ketone was dropped on the coating layer, and it was visually confirmed whether there was a change such as whitening.
No change: ○ Whitening and other changes: ×

[YI (yellowness)]
Measurements were performed according to ASTM E313.

[Pencil hardness]
The measurement was tested according to JIS K5600-5-4. The load was 750 g.

[PI film 1]
In a reaction vessel substituted with nitrogen gas, 1.14 g (10 mmol) of tra-DACH was added, and DMAc was added in an amount of 29.95 g so that the total monomer weight (total of diamine component and carboxylic acid component) was 12% by mass. And stirred at room temperature for 1 hour. To this solution, 2.87 g (9.75 mmol) of s-BPDA and 0.07 g (0.25 mmol) of a-BPDA were gradually added. The mixture was stirred at room temperature for 12 hours to obtain a uniform and viscous polyimide precursor solution.

A polyimide precursor solution filtered through a PTFE membrane filter is applied to a glass substrate, and heated as it is on the substrate at 120 ° C. for 1 hour, 150 ° C. for 30 minutes, 200 ° C. for 30 minutes, and finally 350 ° C. And imidized thermally to obtain a colorless and transparent polyimide film / glass laminate. Subsequently, the obtained polyimide film / glass laminate was immersed in water and then peeled and dried to obtain a polyimide film (PI film 1) having a film thickness of 8 μm.

[Evaluation of polyimide film]
The evaluation results of the polyimide film are shown in Table 1. In Table 3, as Comparative Example 1, YI of PI film 1 is described.

[PI film 2]
Upirex-25S (manufactured by Ube Industries, “Upilex” is a registered trademark), which is a polyimide film with a film thickness of 25 μm, was prepared.

[Evaluation of polyimide film]
The evaluation results of the polyimide film are shown in Table 1. In Table 3, YI of PI film 2 is described as Comparative Example 3.

[PI film 3]
Iupilex-75S (manufactured by Ube Industries, “Iupirex” is a registered trademark), which is a polyimide film having a thickness of 75 μm, was prepared.

[Evaluation of polyimide film]
The evaluation results of the polyimide film are shown in Table 1. In Table 3, as Comparative Example 4, YI of PI film 3 is described.

[PI film 4]
In a reaction vessel substituted with nitrogen gas, 2.12 g (10 mmol) of m-TD was placed, and DMAc was added in an amount of 31.33 g in such an amount that the charged monomer total mass (total of diamine component and carboxylic acid component) was 12 mass%. And stirred at room temperature for 1 hour. To this solution, 1.76 g (9 mmol) of CBDA and 0.38 g (1 mmol) of CpODA were gradually added. The mixture was stirred at room temperature for 12 hours to obtain a uniform and viscous polyimide precursor solution. A mixed solution of 0.096 g of 1,2-dimethylimidazole and 0.096 g of DMAc was added to the resulting solution, and stirred at room temperature for 1 hour to obtain a uniform and viscous polyimide precursor solution.

A polyimide precursor solution filtered through a PTFE membrane filter is applied to a glass substrate, heated in a nitrogen atmosphere as it is from room temperature to 310 ° C. to thermally imidize, and a colorless transparent polyimide film / glass A laminate was obtained. Subsequently, the obtained polyimide film / glass laminate was immersed in water and then peeled and dried to obtain a polyimide film (PI film 4) having a film thickness of 80 μm.

[Evaluation of polyimide film]
The evaluation results of the polyimide film are shown in Table 1. In Table 3, as Comparative Example 6, YI of PI film 4 is described.

[PI film 5]
In a reaction vessel substituted with nitrogen gas, 2.00 g (10 mmol) of 4,4′-ODA was placed, and DMAc was added in such an amount that the total monomer weight (total of diamine component and carboxylic acid component) was 18% by mass 19.33 g was added and stirred at room temperature for 1 hour. To this solution, 2.24 g (10 mmol) of PMDA-HS was gradually added. The mixture was stirred at room temperature for 12 hours to obtain a uniform and viscous polyimide precursor solution.

A polyimide precursor solution filtered through a PTFE membrane filter is applied to a glass substrate, heated in a nitrogen atmosphere as it is from room temperature to 350 ° C., and thermally imidized to form a colorless transparent polyimide film / glass. A laminate was obtained. Next, the obtained polyimide film / glass laminate was immersed in water, peeled and dried to obtain a polyimide film (PI film 5) having a film thickness of 54 μm.

[Evaluation of polyimide film]
The evaluation results of the polyimide film are shown in Table 1. In Table 3, as Comparative Example 7, YI of PI film 5 is described.

[PI film 6]
TFMB 3.20 g (10 mmol) was placed in a reaction vessel substituted with nitrogen gas, and DMAc was added in an amount of 28.78 g so that the total monomer weight (total of diamine component and carboxylic acid component) was 20% by mass. And stirred at room temperature for 1 hour. To this solution, 3.11 g (7 mmol) of 6FDA and 0.88 g (3 mmol) of s-BPDA were gradually added. The mixture was stirred at room temperature for 12 hours to obtain a uniform and viscous polyimide precursor solution.

A polyimide precursor solution filtered through a PTFE membrane filter is applied to a glass substrate, heated in a nitrogen atmosphere as it is from room temperature to 350 ° C., and thermally imidized to form a colorless transparent polyimide film / glass. A laminate was obtained. Next, the obtained polyimide film / glass laminate was immersed in water and then peeled and dried to obtain a polyimide film (PI film 6) having a film thickness of 38 μm.

[Evaluation of polyimide film]
The evaluation results of the polyimide film are shown in Table 1. In Table 3, as Comparative Example 8, YI of PI film 6 is described.

[PI film 7]
A polyimide precursor solution was produced in the same manner as [PI film 4]. The polyimide precursor solution is filtered through a PTFE membrane filter, applied onto Ube Industries' polyimide film, Upilex (registered trademark) -125S, and heated from room temperature to 280 ° C on a glass substrate in a nitrogen atmosphere. Thermal imidization was performed to obtain a colorless and transparent polyimide film / Upilex (registered trademark) -125S laminate (laminate 1). Subsequently, the polyimide film was peeled from the obtained polyimide film / Upilex (registered trademark) -125S laminate. It should be noted that the peeling could be easily performed without being immersed in water or the like. A polyimide film (PI film 7) having a film thickness of 80 μm was obtained.

[Evaluation of polyimide film]
The evaluation results of the polyimide film are shown in Table 1. In Table 4, as Comparative Example 9, YI of PI film 4 was described.

[Coating composition 1]
In a reactor equipped with a stirrer and a heater, ETERNACOLL (registered trademark) UM90 (3/1) (manufactured by Ube Industries; number average molecular weight 916; hydroxyl value 122 mgKOH / g; polyol component 1,4-cyclohexanedimethanol: 1 , 6-hexanediol = 3: 1 polycarbonate diol obtained by reacting a polyol mixture with carbonate ester, 125 grams), 2,2-dimethylolpropionic acid (22.4 grams), Isophorone diisocyanate (120 grams) was heated in N-ethylpyrrolidone (100 grams) in the presence of dibutyltin dilaurate (0.2 grams) at 80-90 ° C. for 3.5 hours. The reaction mixture was cooled to 80 ° C., and triethylamine (17.0 grams) was added and mixed thereto. The reaction mixture is further mixed with a mixture of trimethylolpropane triacrylate (TMPTA) and tripropylene glycol diacrylate (TPGDA) (weight ratio 1: 1, 55.6 grams), and water (672 grams) under strong stirring. Added to the inside. Subsequently, 35% by weight of 2-methyl-1,5-pentanediamine aqueous solution (69.4 grams) was added to disperse the aqueous polyurethane resin having a solid content of 29.4% and an acrylic content of 16.0% in the solid content. Got the body. Solid content here shows the resin component content in an aqueous polyurethane resin dispersion.

The acrylic equivalent of the (meth) acrylate compound (mixture of TMPTA and TPGDA) of this aqueous polyurethane resin dispersion is 119. 0.15 g of BYK-345 (manufactured by ALTANA) as a surfactant was added to 100 g of this aqueous polyurethane resin dispersion, and the mixture was stirred at room temperature to obtain a coating composition 1.

[Coating composition 2]
A coating composition 2 was obtained by adding 1.5 g of a photopolymerization initiator (Irgacure 500, manufactured by BASF) to 100 g of the coating composition 1 and stirring well.

[Coating composition 3]
ETERRNACOLL (registered trademark) UH200 (manufactured by Ube Industries; number average molecular weight 2007; hydroxyl value 55.9 mgKOH / g; polyol component reacts 1,6-hexanediol with carbonate ester in a reactor equipped with a stirrer and a heater. Polycarbonate diol, 190 grams), 2,2-dimethylolpropionic acid (20.4 grams), isophorone diisocyanate (77.0 grams), and 3-methoxy-N, N-dimethylpropane. The reaction was carried out in amide (90.0 grams) by heating at 80-90 ° C. for 5 hours in the presence of dibutyltin dilaurate (0.2 grams) in a nitrogen atmosphere. The reaction mixture was cooled to 80 ° C., and triethylamine (15.0 grams) was added and mixed thereto. The reaction mixture and ethylene oxide modified pentaerythritol tetraacrylate (PE (EO) TTA, 47.6 grams) were further mixed and added into water (724 grams) with vigorous stirring. Subsequently, 35% by weight of 2-methyl-1,5-pentanediamine aqueous solution (29.5 grams) was added to disperse the aqueous polyurethane resin having a solid content of 28.9% and an acrylic content of 13.8% in the solid content. Got the body. Solid content here shows the resin component content in an aqueous polyurethane resin dispersion.

The acrylic equivalent of the (meth) acrylate compound (PE (EO) TTA) of this aqueous polyurethane resin dispersion is 143. To 100 g of this aqueous polyurethane resin dispersion, 0.15 g of BYK-345 (manufactured by ALTANA) as a surfactant was added and stirred at room temperature to obtain coating composition 3.

[Coating composition 4]
As the acrylate compound, a mixture of trimethylolpropane triacrylate (TMPTA) and tripropylene glycol diacrylate (TPGDA) (weight ratio 1: 1, 113 grams) was mixed with the reaction mixture, and the water was mixed under strong stirring. (800 grams), except that the aqueous polyurethane resin dispersion having a solid content of 29.6% and an acrylic content of 27.9% in the solid content was the same as the production of the coating composition 1 described above. Obtained. Thereafter, the coating composition 4 was obtained in the same manner.

[Coating composition 5]
As the acrylate compound, except that a mixture of trimethylolpropane triacrylate (TMPTA) and tripropylene glycol diacrylate (TPGDA) (weight ratio 1: 1, 16 grams) was used, the same as in the production of the coating composition 4, An aqueous polyurethane resin dispersion having a solid content of 29.6% and an acrylic content in the solid content of 5% was obtained. Thereafter, the coating composition 5 was obtained in the same manner.

[Comparative coating composition 1]
Comparative coating composition 1 was obtained in the same manner as coating composition 1 except that the acrylate compound was not added.

[Hard coat]
Hard coat a: STR-SiA manufactured by Taisei Fine Chemical Co., Ltd. was used. STR-SiA
To 100 g, 3 g of IRUGACURE (registered trademark) 184 was added as a photoinitiator and stirred at room temperature to obtain a hard coat solution (hard coat a).
Hard coat b: FUJIHARD (registered trademark) HO3313U-8 manufactured by Fujikura Kasei

[Example 1]
On the PI film 1, the coating composition 1 was uniformly applied so that the film thickness after drying was 3 μm. Subsequently, it was made to dry and harden | cure at 80 degreeC for 30 minutes and 150 degreeC for 30 minutes, the coating layer was formed on the polyimide film, and the polyimide film laminated body was obtained.

[Evaluation of polyimide film laminate]
The adhesion between the polyimide film and the coating layer was evaluated by a cross-cut test. Moreover, solvent resistance and YI were evaluated using methyl ethyl ketone. The results are shown in Table 2.

[Examples 2 and 3]
The coating composition 1 was uniformly applied on the PI films 2 and 3 (corresponding to Examples 2 and 3 respectively) so that the film thickness after drying was 2 μm. Subsequently, it was dried and cured at 80 ° C. for 30 minutes and 150 ° C. for 30 minutes, and a coating layer was formed on the polyimide film to obtain a polyimide film laminate.

[Examples 4 and 5]
On the PI film 4, coating compositions 1 and 3 (corresponding to Examples 4 and 5 respectively) were uniformly applied so that the film thickness after drying was 2 μm. Subsequently, it was made to dry and harden | cure at 80 degreeC for 30 minutes and 150 degreeC for 30 minutes, the coating layer was formed on the polyimide film, and the polyimide film laminated body was obtained.

[Examples 6 and 7]
On the PI film 4, the coating composition 1 was uniformly applied so that the film thickness after drying was 4 μm and 0.5 μm (corresponding to Examples 6 and 7, respectively). Subsequently, it was made to dry and harden | cure at 80 degreeC for 30 minutes and 150 degreeC for 30 minutes, the coating layer was formed on the polyimide film, and the polyimide film laminated body was obtained.

Example 8
On the PI film 4, the coating composition 2 was uniformly applied so that the film thickness after drying was 2 μm. Subsequently, the coating film (before ultraviolet irradiation) was obtained by drying at 80 degreeC for 30 minutes. A polyimide film laminate was obtained by passing under an 80 W metal halide lamp (single irradiation, ultraviolet irradiation amount 1000 mJ / cm 2) to form a coating layer on the polyimide film.

[Examples 9 and 10]
On the PI films 5 and 6 (corresponding to Examples 9 and 10 respectively), the coating composition 1 was uniformly applied so that the film thickness after drying was 2 μm. Subsequently, it was dried and cured at 80 ° C. for 30 minutes and 150 ° C. for 30 minutes, and a coating layer was formed on the polyimide film to obtain a polyimide film laminate.

[Comparative Examples 2 and 5]
On the PI films 2 and 4 (corresponding to Comparative Examples 2 and 5 respectively), the comparative coating composition 1 was uniformly applied so that the film thickness after drying was 2 μm. Subsequently, it was dried and cured at 80 ° C. for 30 minutes and 150 ° C. for 30 minutes, and a coating layer was formed on the polyimide film to obtain a polyimide film laminate.

[Evaluation of polyimide film laminate]
The adhesion between the polyimide film and the coating layer was evaluated by a cross-cut test. Moreover, solvent resistance and YI were evaluated using methyl ethyl ketone. The results are shown in Table 3.

[Examples 11 and 12]
On the PI film 7, the coating composition 4 (Example 11) and the coating composition 5 (Example 12) were uniformly applied so that the film thickness after drying was 2 μm. Subsequently, it was made to dry and harden | cure at 80 degreeC for 5 minutes and 150 degreeC for 5 minutes, the coating layer was formed on the polyimide film, and the polyimide film laminated body (laminated body 2, 3) was obtained.

[Evaluation of polyimide film laminate]
The adhesion between the polyimide film and the coating layer was evaluated by a cross-cut test. Moreover, solvent resistance and YI were evaluated using methyl ethyl ketone. The results are shown in Table 4.

[Examples 13 to 15]
The coating composition 1 is uniformly applied on the PI film 7 using a spin coater so that the film thickness after drying is 500 nm (Example 13), 100 nm (Example 14), and 30 nm (Example 15), respectively. It was applied to. Subsequently, it was dried and cured at 80 ° C. for 5 minutes and 150 ° C. for 5 minutes, and a coating layer was formed on the polyimide film to obtain polyimide film laminates (laminates 4 to 6).

[Comparative Example 10]
On the PI film 7, the coating composition 1 was uniformly applied so that the film thickness after drying was 5 μm. Subsequently, it was made to dry and harden | cure at 80 degreeC for 5 minutes and 150 degreeC for 5 minutes, the coating layer was formed on the polyimide film, and the polyimide film laminated body (laminated body 7) was obtained.

[Examples 16 to 18]
The hard coat a is applied on the coating layers of the obtained laminates 4 to 6 with a bar coater so that the thickness of the hard coat layer after drying is about 10 μm, dried at 80 ° C. for 10 minutes, and high pressure mercury The lamp was used to irradiate with ultraviolet rays so that the integrated light amount was 1000 mJ / cm 2. Then, it heated at 150 degreeC for 10 minute (s), and obtained the polyimide / coating layer / hard-coat laminated body.

[Evaluation of polyimide film laminate]
The evaluation results are shown in Table 5.

Example 19
A hard coat b is applied on the coating layer of the obtained laminate 4 with a bar coater so that the thickness of the hard coat layer after drying is about 10 μm, and dried at 80 ° C. for 10 minutes. It was used to irradiate with ultraviolet rays so that the accumulated light amount was 1000 mJ / cm ² . Then, it heated at 150 degreeC for 10 minute (s), and obtained the polyimide / coating layer / hard-coat laminated body.

[Comparative Examples 11 and 12]
Bar coater so that the thickness of the hard coat layer after drying the hard coat a on the laminate 7 (Comparative Example 12) obtained in the PI film 7 (Comparative Example 11) and Comparative Example 10 is about 10 μm. The film was dried at 80 ° C. for 10 minutes, and irradiated with ultraviolet rays using a high-pressure mercury lamp so that the integrated light amount became 1000 mJ / cm ² . Then, it heated at 150 degreeC for 10 minute (s), and obtained the polyimide / coating layer / hard-coat laminated body.

[Comparative Example 13]
On the PI film 7, the hard coat b is coated with a bar coater so that the thickness of the hard coat layer after drying is about 10 μm, and dried at 80 ° C. for 10 minutes. Ultraviolet rays were irradiated so as to be 1000 mJ / cm 2. Then, it heated at 150 degreeC for 10 minute (s), and obtained the polyimide / coating layer / hard-coat laminated body.

[Examples 20 and 21]
Coating with a bar coater so that the thickness of the hard coat layer after drying the hard coat b on the coating layer of the obtained laminate 2 (Example 20) and laminate 3 (Example 21) is about 10 μm. Then, it was dried at 80 ° C. for 10 minutes, and irradiated with ultraviolet rays using a high-pressure mercury lamp so that the integrated light amount became 1000 mJ / cm 2. Then, it heated at 150 degreeC for 10 minute (s), and obtained the polyimide / coating layer / hard-coat laminated body.

[Example 22]
On the PI film 7 of the laminate 1 (PI film 7 / UPILEX (registered trademark) -125S laminate), the coating composition 1 is applied using a spin coater so that the film thickness after drying becomes 0.5 μm. It was applied evenly. Subsequently, it was made to dry and harden | cure at 80 degreeC for 5 minutes and 150 degreeC for 5 minutes, the coating layer was formed on the polyimide film, and the polyimide film laminated body was obtained. On the coating layer of this laminate, the hard coat a is coated with a bar coater so that the thickness of the hard coat layer after drying is about 10 μm, dried at 80 ° C. for 10 minutes, and integrated using a high-pressure mercury lamp. Ultraviolet rays were irradiated so that the amount of light was 1000 mJ / cm ² . Then, it heated at 150 degreeC for 10 minute (s), and obtained the polyimide (Upilex (trademark) -125S) / polyimide (PI film 7) / coating layer / hard coat laminated body. Thereafter, the polyimide (PI film 7) / coating layer / hard coat laminate was peeled from Upilex (registered trademark) -125S. It should be noted that the peeling could be easily performed without being immersed in water or the like.

According to the present invention, a polyimide film laminate having improved adhesion to other functional layers while taking advantage of conventional characteristics of polyimide film such as chemical resistance, mechanical strength, electrical characteristics, and dimensional stability. Can be provided. In particular, it can be suitably used as a substrate for a display, a touch panel, a solar cell, a protective film, or the like.

Claims

Polyimide film,
A polyimide film laminate having a coating layer formed of a cured product of a coating composition containing a polyurethane resin and a (meth) acrylate compound on the surface of the polyimide film (however, the polyurethane resin is , Urethane (meth) acrylate monomer and polymer thereof are not included.)
The polyimide which comprises the said polyimide film contains the repeating unit represented by following General formula (1), The polyimide film laminated body of Claim 1 characterized by the above-mentioned.

(In the formula, X 1 is a tetravalent group having an aromatic ring or alicyclic structure, and Y 1 is a divalent group having an aromatic ring or alicyclic structure.)
The content of the repeating unit represented by the chemical formula (1) in which X 1 is a tetravalent group having an alicyclic structure and Y 1 is a divalent group having an alicyclic structure is based on the total repeating units. The polyimide film laminate according to claim 2, wherein the polyimide film laminate is 50 mol% or less.
The polyimide film laminate according to claim 2, wherein X 1 in the chemical formula (1) is a tetravalent group having an aromatic ring, and Y 1 is a divalent group having an aromatic ring. .
The polyimide film laminate according to claim 2, wherein X 1 in the chemical formula (1) is a tetravalent group having an alicyclic structure, and Y 1 is a divalent group having an aromatic ring. .
The polyimide film laminate according to claim 2, wherein X 1 in the chemical formula (1) is a tetravalent group having an aromatic ring, and Y 1 is a divalent group having an alicyclic structure. .
The polyimide according to any one of claims 1 to 6, wherein the content of the (meth) acrylate compound is 5 to 50% by weight of a solid content based on a resin component in the coating composition. Film laminate.
The polyimide film laminate according to any one of claims 1 to 7, wherein the polyurethane resin includes a structure in which a polycarbonate polyol and a polyisocyanate compound are reacted.
The polyimide film laminate according to any one of claims 1 to 8, wherein the coating layer has a thickness of 10 nm or more and less than 5 µm.
The polyimide film laminate according to any one of claims 1 to 8, further comprising a surface layer on the surface of the coating layer, wherein the surface has a pencil hardness of 2H or more.
The thickness of the coating layer is 10 nm or more and less than 5 μm, further has a surface layer on the surface of the coating layer, and the pencil hardness of the surface layer is 2H or more. The polyimide film laminated body of any one of Claims 1.
The polyimide film laminate according to claim 10 or 11, wherein the surface layer is formed of a cured product of a curable resin composition containing at least a curable resin component and an inorganic filler.
Applying a coating composition containing a polyurethane resin and a (meth) acrylate compound to the surface of the polyimide film;
A method of producing a polyimide film laminate, wherein the coating film of the coating composition is cured to form a coating layer (wherein the polyurethane resin comprises a urethane (meth) acrylate monomer and its weight). Does not include coalescence.)
Applying a curable resin composition containing at least a curable resin component and an inorganic filler to the surface of the coating layer of the polyimide film laminate according to any one of claims 1 to 9,
And a step of curing the coating film of the curable resin composition to form a surface layer.