JP6780272B2 - Polymer composite film - Google Patents

Description

The present invention relates to a polymer composite film containing a condensation polymer film and a silicone resin layer, and more particularly, a silicone resin having flexibility, elasticity, and heat resistance, and dimensional stability with a relatively high elasticity. The present invention relates to a polymer composite film that takes advantage of each other's merits, and is composed of a condensed polymer film having good workability and excellent workability.

Silicone resin is a general term for polymer compounds having a main skeleton due to siloxane bonds. Various silicone resins are known depending on their molecular weight, degree of cross-linking, substituents, etc., but their physical properties are adjusted so as to have excellent properties such as heat resistance, water resistance, chemical resistance, and electrical properties, and particularly to have appropriate elasticity. Silicone resin is called silicone rubber or silicone elastomer, and is required to have both flexibility and heat resistance. Gaskets, sealing materials, diaphragms, laminator rolls, electrophotographic toner fixing rolls, protective members for medical use, and cosmetic molding. It is still widely used. In addition, since it has poor adhesiveness, it is also useful as a release sheet and cushioning material.

Although it is a silicone resin with excellent properties, it is rarely used for electronic substrate applications. The reason is that it has poor adhesiveness and it is difficult to combine it with multiple materials such as copper foil. Moreover, because it is a flexible material, it is difficult from the viewpoint of dimensional stability.

Silicone resin has a drawback that it is slightly inferior in mechanical strength because it is flexible. It can be exemplified that it is used as a cushion sheet material in press working as an application utilizing the characteristics of silicone resin having heat resistance, elasticity, and good releasability. In such an application, if the pressure applied to the silicone resin sheet is too strong, the sheet may be stretched in the surface direction, and the silicone resin sheet itself may be cracked or broken. Furthermore, when the silicone resin sheet is broken, the material to be pressed may be involved and even broken together.
In order to solve such a problem, an attempt has been made to arrange a reinforcing material on the silicone resin sheet. Products in which a reinforcing material such as glass cloth is inserted in a silicone resin sheet are already known. The mechanical strength can be improved by inserting the cloth-shaped reinforcing material into the sheet, but the cross-shaped reinforcing material is inhomogeneous, and such reinforcement impairs the flexibility of the sheet. is there.
The same reinforcing effect can be obtained by laminating a silicone resin sheet with a silicone resin such as a metal foil / metal plate, glass plate, or ceramic plate having good dimensional stability, or a hard substrate such as a glass epoxy plate. As a result, flexibility is often impaired due to the influence of many physical properties.
An organic polymer film or an organic polymer sheet can be used as a reinforcing material that makes the most of the flexibility of the silicone resin, but since the adhesiveness between the silicone resin and the organic polymer material is poor, problems such as peeling during use occur. Often.

For example, Patent Document 1 discloses an example in which an endless belt in which a silicone resin is provided on the surface of a polyimide resin film processed into a seamless belt shape is used as an intermediate transfer belt of an electrophotographic printer. For example, Patent Document 2 discloses an example of a pressure-sensitive adhesive sheet using a polyimide resin film as an equipment and a silicone resin as a pressure-sensitive adhesive. Further, Patent Document 3 discloses an example in which a polymer composite film consisting of a polyimide resin film and a silicone resin film is used as a fixing film for an electrophotographic printer.

Japanese Unexamined Patent Publication No. 2012-159737 JP-A-2007-266558 Japanese Unexamined Patent Publication No. 9-274402

As described above, the silicone resin has excellent properties of achieving both heat resistance and flexibility, but due to its high chemical resistance and good peelability, it can be laminated with other materials. It was perceived as one of the difficult materials to combine. An object of the present invention is to solve such a problem and to provide a polymer composite film containing a silicone resin layer and a condensation polymer film, which has excellent adhesiveness (peeling strength) and good appearance quality.

As a result of intensive studies to solve this problem by surface treatment on the side of the condensed polymer film, the present inventors applied a silane coupling agent to the silicone resin in the vapor phase to obtain the polymer. A polymer composite film having good adhesiveness without foreign matter intervening between the film and the silicone resin layer is provided, and as a result, it is possible to manufacture a high-definition flexible electronic device with high yield, and the recyclability of the silicone resin is high. We have found that it can be improved and completed the present invention.

That is, the present invention has the following configuration.
[1] A polymer composite film comprising a layer made of at least a resin containing polydimethylsiloxane as a main component and a layer made of a condensed polymer, and having a total thickness of 1 μm or more and 20 μm or less.
[2] A polymer composite film having a layer made of a resin containing polydimethylsiloxane as a main component on both sides, wherein the total thickness is 1 μm or more and 20 μm or less.
[3] The polymer composite film according to [1] or [2], wherein the condensed polymer film is a polyester film.
[4] The polymer composite film according to [1] or [2], wherein the condensed polymer film is a polyimide film.

According to the present invention, it is possible to obtain an excellent composite film having the advantages of both an engineering plastic film having excellent mechanical properties and a silicone resin having excellent surface properties.
In the present invention, more preferably, if a condensed polymer film having high heat resistance is used, it is possible to bond the polymer composite film without using an adhesive or an adhesive having inferior heat resistance. It can be used in high temperature areas. In particular, when a polyimide film is used as the condensation polymer film, it can be used in a high temperature range of 180 ° C. or higher, preferably 230 ° C. or higher, more preferably 260 ° C. or higher, and can be pressed at a high temperature. It can be suitably used in applications such as cushioning materials used for laminating, electronic parts accompanied by soldering, and transport members used in a high temperature environment.

The polymer composite film of the present invention is a polymer composite film composed of at least a silicone resin layer, a condensation polymer film, and a silane coupling agent layer.

<Silicone resin>
The silicone resin forming the silicone resin layer in the present invention refers to a silicon-based polymer compound having a main skeleton formed by a siloxane bond, which is solid at room temperature. As the silicone resin preferably used in the present invention, it is preferable to use a silicone resin having a polydialkylsiloxane as a basic skeleton and having its molecular weight, degree of cross-linking, substituents and the like adjusted according to the purpose. By selecting the substituent to be introduced and making the skeleton a cyclic or branched structure, the silicone resin can enhance or impart various functions such as heat resistance, chemical resistance, hydrophilicity and hydrophobicity.
The substituents introduced into the silicone resin of the present invention include methyl group, ethyl group, propyl group, butyl group, phenyl group, substituted phenyl group, polyether group, epoxy group, amino group, amino group-containing substituent and carboxyl. Such substituents, such as groups, aralkyl groups, etc., can be introduced at the side chain or at the end of the molecule.
In the present invention, a silicone resin having polydimethylsiloxane or polydiphenylsiloxane as a main skeleton, and a polysiloxane resin containing both a methyl group and a phenyl group are preferable.
As the silicone resin of the present invention, a one-component type or a two-component type silicone resin can be used.
In the two-component silicone resin, the main material, the cross-linking agent, the reaction accelerator, and the like are separated as a curing agent, and both are mixed and used before use. Suitable methods and / or catalysts used to crosslink the silicone resins of the present invention include condensation catalysts. By preparing a silicone resin with suitable reactive groups, other catalysts and initiators, such as silane-olefin addition (hydrosilation) catalysts, free radical catalysts such as peroxide catalysts, heat, and ultraviolet rays Radical exposure can be used.
Free radical catalysts, such as peroxide catalysts, can be used as blend-hardeners or catalysts when the silicone resin contains vinyl groups.
When the silicone resin has a Si—H group at the terminal position, or when the resin has a terminal double bond, a silane-olefin addition catalyst is useful.
Silicone compounds having a hydroxyl group therein, such as the silanol-terminated polydiorganosiloxane containing silanol-terminated (terminalized) polydimethylsiloxane, can also be thermally catalyzed.
Preferred curing systems include condensation reactions. Silica acid esters such as tetraethyl silicate react with the hydroxy end groups of the diorganosiloxane of the composition of the invention in a condensation reaction. Alcohol is released in this reaction and the reaction is catalyzed by a metal soap such as dibutyltin dilaurate.
A still more preferred catalyst is an organic zinc compound such as zinc hexanoate. A condensation catalyst such as zinc hexanoate conducts a condensation reaction between a silanol-terminated group present in silanol-terminated polydiorganosiloxane and a residual hydroxy group (silanol) considered to be present in the polydimethylsiloxane polymer and methylphenylsesquisiloxane. It is conceivable to catalyze.

<Condensation polymer film>
The condensed polymer film in the present invention includes polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, total aromatic polyester, other copolymerized polyester, polymethylmethacrylate, other copolymerized acrylate, polycarbonate, and polyamide. , Polysulphon, polyethersulphon, polyether ketone, polyamideimide, polyetherimide, aromatic polyimide, alicyclic polyimide, fluorinated polyimide, cellulose acetate, cellulose nitrate, aromatic polyamide, polyvinyl chloride, polyphenol, polyarylate , Polyphenylene sulfide, polyphenylene oxide, polystyrene and other films can be used. What is particularly effective and useful in the present invention is a polymer having a heat resistance of 100 ° C. or higher, a so-called engineering plastic film. Here, heat resistance refers to the glass transition temperature or the thermal deformation temperature.

Among the polymer materials of the condensed polymer film of the present invention, a film can be obtained by a melt-stretching method for a thermoplastic polymer material.

The thickness of the condensed polymer film of the present invention is preferably 3 μm or more, and more preferably 11 μm or more. The upper limit of the thickness of the condensed polymer film is not particularly limited, but is preferably 250 μm or less, more preferably 150 μm or less, and further preferably 90 μm or less, according to the requirements for a flexible electronic device.
The area of the condensed polymer film of the present invention (that is, the area of the polymer composite film) is preferably a large area from the viewpoint of production efficiency and cost of the polymer composite film and the flexible electronic device. It is preferably 1000 cm ² or more, more preferably 1500 cm ² or more, more preferably 2000 cm ² or more.

The condensation polymer film particularly preferably used in the present invention is a polyimide film, and aromatic polyimide, alicyclic polyimide, polyamideimide, polyetherimide and the like can be used. When the present invention is particularly used for manufacturing a flexible display element, it is preferable to use a polyimide resin film having colorless transparency, but particularly when forming a back element of a reflective or self-luminous display. This is not the case.

Generally, a polyimide film is a green film (“precursor film”) in which a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent is applied to a support for producing a polyimide film and dried. (Also referred to as "polyamic acid film"), and further obtained by subjecting the green film to a high-temperature heat treatment to carry out a dehydration ring-closing reaction on a support for producing a polyimide film or in a state of being peeled off from the support.

The diamines constituting the polyamic acid are not particularly limited, and aromatic diamines, aliphatic diamines, alicyclic diamines and the like usually used for polyimide synthesis can be used. From the viewpoint of heat resistance, aromatic diamines are preferable, and among aromatic diamines, aromatic diamines having a benzoxazole structure are more preferable. When aromatic diamines having a benzoxazole structure are used, it is possible to develop high elastic modulus, low coefficient of thermal expansion, and low linear expansion coefficient as well as high heat resistance. The diamines may be used alone or in combination of two or more.

The aromatic diamines having a benzoxazole structure are not particularly limited, and for example, 5-amino-2- (p-aminophenyl) benzoxazole, 6-amino-2- (p-aminophenyl) benzoxazole, 5 -Amino-2- (m-aminophenyl) benzoxazole, 6-amino-2- (m-aminophenyl) benzoxazole, 2,2'-p-phenylenebis (5-aminobenzoxazole), 2,2' -P-Phenylenebis (6-aminobenzoxazole), 1- (5-aminobenzoxazole) -4- (6-aminobenzoxazolo) benzene, 2,6- (4,4'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (4,4-diaminodiphenyl) benzo [1,2-d: 4,5-d'] bisoxazole, 2, 6- (3,4'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (3,4'-diaminodiphenyl) benzo [1,2-d: 4,5-d'] bisoxazole, 2,6- (3,3'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (3,3') -Diaminodiphenyl) benzo [1,2-d: 4,5-d'] bisoxazole and the like can be mentioned.

Examples of aromatic diamines other than the above-mentioned aromatic diamines having a benzoxazole structure include 2,2'-dimethyl-4,4'-diaminobiphenyl and 1,4-bis [2- (4-aminophenyl). ) -2-propyl] benzene (bisaniline), 1,4-bis (4-amino-2-trifluoromethylphenoxy) benzene, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 4,4 '-Bis (4-aminophenoxy) biphenyl, 4,4'-bis (3-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl ] Sulfates, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl ] -1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 3,3'- Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4' −Diaminodiphenylsulfoxide, 3,3′-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 4, 4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis [4- (4-aminophenoxy) phenyl] methane, 1,1-bis [ 4- (4-Aminophenoxy) phenyl] ethane, 1,2-bis [4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [4- (4-aminophenoxy) phenyl] propane, 1, 2-Bis [4- (4-aminophenoxy) phenyl] propane, 1,3-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] Propane, 1,1-bis [4- (4-aminophenoxy) phenyl] butane, 1,3- Bis [4- (4-aminophenoxy) phenyl] butane, 1,4-bis [4- (4-aminophenoxy) phenyl] butane, 2,2-bis [4- (4-aminophenoxy) phenyl] butane, 2,3-Bis [4- (4-aminophenoxy) phenyl] butane, 2- [4- (4-aminophenoxy) phenyl] -2- [4- (4-aminophenoxy) -3-methylphenyl] propane , 2,2-Bis [4- (4-aminophenoxy) -3-methylphenyl] propane, 2- [4- (4-aminophenoxy) phenyl] -2- [4- (4-aminophenoxy) -3 , 5-Dimethylphenyl] propane, 2,2-bis [4- (4-aminophenoxy) -3,5-dimethylphenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] -1 , 1,1,3,3,3-hexafluoropropane, 1,4-bis (3-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-amino) Phenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (4-Aminophenoxy) phenyl] sulfoxide, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] Ether, 1,3-bis [4- (4-aminophenoxy) benzoyl] benzene, 1,3-bis [4- (3-aminophenoxy) benzoyl] benzene, 1,4-bis [4- (3-amino) benzoyl] Phenoxy) benzoyl] benzene, 4,4'-bis [(3-aminophenoxy) benzoyl] benzene, 1,1-bis [4- (3-aminophenoxy) phenyl] propane, 1,3-bis [4- ( 3-Aminophenoxy) Phenyl] Propane, 3,4'-Diaminodiphenylsulfide, 2,2-Bis [3- (3-Aminophenoxy) Phenyl] -1,1,1,3,3,3-Hexafluoropropane , Bis [4- (3-aminophenoxy) phenyl] methane, 1,1-bis [4- (3-aminophenoxy) phenyl] ethane, 1,2-bis [4- (3-aminophenoxy) phenyl] ethane , Bis [4- (3-aminophenoxy) phenyl] sulfoxide, 4,4'-bis [ 3- (4-Aminophenoxy) Benzene] diphenyl ether, 4,4'-bis [3- (3-Aminophenoxy) benzoyl] diphenyl ether, 4,4'-bis [4- (4-amino-α, α-dimethyl) Benzene) phenoxy] benzophenone, 4,4'-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] diphenylsulfone, bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone , 1,4-bis [4- (4-aminophenoxy) phenoxy-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-aminophenoxy) phenoxy-α, α-dimethylbenzyl] benzene , 1,3-bis [4- (4-amino-6-trifluoromethylphenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-fluorophenoxy)- α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-methylphenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-) 6-Cyanophenoxy) -α, α-dimethylbenzyl] Benzene, 3,3'-diamino-4,4'-diphenoxybenzophenone, 4,4'-diamino-5,5'-phenoxybenzophenone, 3,4' -Diamino-4,5'-diphenoxybenzophenone, 3,3'-diamino-4-phenoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone, 3,4'-diamino-4-phenoxybenzophenone, 3, 4'-diamino-5'-phenoxybenzophenone, 3,3'-diamino-4,4'-dibiphenoxybenzophenone, 4,4'-diamino-5,5'-dibiphenoxybenzophenone, 3,4'-diamino- 4,5'-Dibiphenoxybenzophenone, 3,3'-diamino-4-biphenoxybenzophenone, 4,4'-diamino-5-biphenoxybenzophenone, 3,4'-diamino-4-biphenoxybenzophenone, 3, 4'-Diamino-5'-biphenoxybenzophenone, 1,3-bis (3-amino-4-phenoxybenzoyl) benzene, 1,4-bis (3-amino-4-phenoxybenzoyl) benzene, 1,3- Bis (4-amino-5-phenoxybenzoyl) benzene, 1,4-bis (4-amino-5-phenoxybenzoyl) benzene, 1,3-bis (3-amino-4-bipheno) Xybenzoyl) benzene, 1,4-bis (3-amino-4-biphenoxybenzoyl) benzene, 1,3-bis (4-amino-5-biphenoxybenzoyl) benzene, 1,4-bis (4-amino) -5-biphenoxybenzoyl) benzene, 2,6-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] benzonitrile, and some of the hydrogen atoms on the aromatic ring of the above aromatic diamines or All are halogen atoms, alkyl or alkoxyl groups with 1-3 carbon atoms, cyano groups, or halogenation of 1 to 3 carbon atoms in which some or all of the hydrogen atoms of the alkyl or alkoxyl groups are substituted with halogen atoms. Examples thereof include aromatic diamines substituted with an alkyl group or an alkoxyl group.

Examples of the aliphatic diamines include 1,2-diaminoethane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,8-diaminooctane and the like.
Examples of the alicyclic diamines include 1,4-diaminocyclohexane and 4,4'-methylenebis (2,6-dimethylcyclohexylamine).
The total amount of diamines (aliphatic diamines and alicyclic diamines) other than aromatic diamines is preferably 20% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less of all diamines. Is. In other words, the aromatic diamines are preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more of all diamines.

Examples of the tetracarboxylic acids constituting the polyamic acid include aromatic tetracarboxylic acids (including the acid anhydride thereof), aliphatic tetracarboxylic acids (including the acid anhydride), and alicyclic tetracarboxylic acids usually used for polyimide synthesis. Acids (including their acid anhydrides) can be used. Among them, aromatic tetracarboxylic dianhydrides and alicyclic tetracarboxylic dianhydrides are preferable, aromatic tetracarboxylic dianhydrides are more preferable from the viewpoint of heat resistance, and alicyclics are more preferable from the viewpoint of light transmission. Group tetracarboxylic acids are more preferred. When these are acid anhydrides, the number of anhydride structures in the molecule may be one or two, but those having two anhydride structures (dianhydride) are preferable. Good. The tetracarboxylic acids may be used alone or in combination of two or more.

Examples of the alicyclic tetracarboxylic acid include cyclobutanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3,3', 4,4'-bicyclohexyltetracarboxylic acid and the like. Examples include carboxylic acids and their acid anhydrides. Among these, dianhydrides having two anhydride structures (eg, cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3', 4,4 '-Bicyclohexyltetracarboxylic dianhydride, etc.) is suitable. The alicyclic tetracarboxylic acids may be used alone or in combination of two or more.
When transparency is important, the alicyclic tetracarboxylic acids are, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more of all tetracarboxylic acids.

The aromatic tetracarboxylic acids are not particularly limited, but are preferably pyromellitic acid residues (that is, those having a structure derived from pyromellitic acid), and more preferably an acid anhydride thereof. Examples of such aromatic tetracarboxylic acids include pyromellitic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 4,4'-oxydiphthalic acid dianhydride, and 3 , 3', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic dianhydride, 2,2-bis [4- (3,4-di) Carboxylic phenoxy) phenyl] propanoic acid anhydride and the like can be mentioned.
When heat resistance is important, the aromatic tetracarboxylic acids are, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more of all tetracarboxylic acids.

In the polyimide film of the present invention, it is preferable that the glass transition temperature is preferably 250 ° C. or higher, more preferably 300 ° C. or higher, further preferably 350 ° C. or higher, or no glass transition point is observed in the region of 500 ° C. or lower. The glass transition temperature in the present invention is determined by differential thermal analysis (DSC).

The coefficient of linear expansion (CTE) of the condensed polymer film of the present invention is preferably -5 ppm / K to + 20 ppm / K, more preferably -5 ppm / K to + 15 ppm / K, and further preferably 1 ppm / K. It is K to +10 ppm / K. When the CTE is in the above range, the effective coefficient of linear expansion of the entire polymer composite film can be kept small, and the dimensional stability of the polymer composite film is improved.
The coefficient of linear expansion in the present invention uses an average value between 30 and 200 ° C., but the temperature range of interest varies depending on the application, and the range of 30 ° C. to 400 ° C. is set in consideration of the process at high temperature. When examining, it may be in the range of 100 ° C to 400 ° C, when examining the range of 50 ° C to 280 ° C when soldering is involved, and when applied to automobile parts, etc., the operating temperature range is -50. In some cases, the range of ° C to 150 ° C is emphasized.

The breaking strength of the condensed polymer film in the present invention is preferably 60 MPa or more, more preferably 120 MPa or more, still more preferably 240 MPa or more. There is no limit to the upper limit of breaking strength, but it is practically less than about 1000 MPa. Here, the breaking strength of the condensed polymer film refers to an average value in the length direction and the width direction of the condensed polymer film.
The adhesive strength between the condensed polymer film and the silicone resin in the present invention is preferably 1/2 or less of the breaking strength of the condensed polymer film.
It is assumed that the polymer composite film of the present invention using a film having a thickness of 10 μm has an adhesive strength of 0.5 N / cm.
The breaking force applied to the film having a width of 10 mm is 0.5 N / (10 μm × 10 mm) = 0.5 N / 0.1 mm ² = 5 MPa. In such a case, if the film has a breaking strength of about 10 times this, that is, 50 MPa or more, the peeling operation can be performed without any trouble when peeling the film.
The adhesive strength is more preferably 1/3 or less, still more preferably 1/4 or less of the breaking strength of the condensed polymer film.

The thickness unevenness of the condensed polymer film in the present invention is preferably 20% or less, more preferably 12% or less, still more preferably 7% or less, and particularly preferably 4% or less. If the thickness spots exceed 20%, it tends to be difficult to apply to narrow areas. The thickness unevenness of the film can be obtained, for example, by randomly extracting about 10 positions from the film to be measured with a contact-type film thickness meter and measuring the film thickness based on the following formula.
Film thickness spots (%)
= 100 x (maximum film thickness-minimum film thickness) ÷ average film thickness

The condensed polymer film in the present invention is preferably obtained in the form of being wound as a long film having a width of 300 mm or more and a length of 10 m or more at the time of its manufacture, and is a roll wound around a winding core. The one in the form of a shape film is more preferable.

In the condensed polymer film, in order to ensure handleability and productivity, a lubricant (particle) is added and contained in the film to impart fine irregularities to the condensed polymer film to ensure slipperiness. It is preferable to do so. The lubricant (particles) are fine particles preferably composed of inorganic substances, such as metals, metal oxides, metal nitrides, metal carbonized products, metal acid salts, phosphates, carbonates, talc, mica, clay, and the like. Particles composed of clay minerals, etc. can be used. Preferably, metal oxides such as silicon oxide, calcium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, calcium pyrophosphate, hydroxyapatite, calcium carbonate, and glass filler, phosphates, and carbonates can be used. The lubricant may be of only one type or of two or more types.

The volume average particle diameter of the lubricant (particle) is usually 0.001 to 10 μm, preferably 0.03 to 2.5 μm, more preferably 0.05 to 0.7 μm, and further preferably 0.05 to 0.05. It is 0.3 μm. The volume average particle diameter is based on the measured value obtained by the light scattering method. If the particle size is smaller than the lower limit, industrial production of the condensed polymer film becomes difficult, and if the particle size exceeds the upper limit, the surface irregularities become too large and the sticking strength becomes weak, which may cause practical problems.

The amount of the lubricating material added is 0.02 to 50% by mass, preferably 0.04 to 3% by mass, and more preferably 0.08 to 0.08 to 50% by mass as the amount added to the polymer component in the condensed polymer film. It is 1.2% by mass. If the amount of the lubricating material added is too small, it is difficult to expect the effect of adding the lubricating material, and the slipperiness is not so ensured, which may hinder the production of the condensed polymer film. If the amount is too large, the surface unevenness of the film becomes large. Even if the slipperiness is ensured, the smoothness may be lowered, the breaking strength and breaking elongation of the condensed polymer film may be lowered, and the CTE may be increased.

When a lubricant (particles) is added / contained in the condensation polymer film, it may be a single-layer condensation polymer film in which the lubricant is uniformly dispersed. For example, one surface contains the lubricant. As a multi-layered condensed polymer film composed of a condensed polymer film and having a small amount of lubricating material even if the other surface does not contain or contains lubricating material. Good. In such a multilayer polymer film, fine irregularities are imparted to the surface of one layer (film) so that the layer (film) can ensure slipperiness, and good handleability and productivity can be ensured. it can.

In the case of a film produced by the melt-stretching film forming method, for example, the multilayer condensation polymer film is first formed into a film using a lubricant-free condensed polymer film raw material, and at least in the process of the film. It can be obtained by applying a resin layer containing a lubricant on one side. Of course, the opposite is true, and film formation is performed using a condensing polymer film raw material containing a lubricant, and the condensing polymer film raw material containing no lubricant is applied during the process or after the film formation is completed. You can also get a film.
The same applies to a condensed polymer film obtained by using a solution film forming method such as a polyimide film. For example, as a polyamic acid solution (polyimide precursor solution), a lubricant (preferably an average particle size of 0. 0.02% by mass to 50% by mass (preferably 0.04 to 3% by mass, more preferably 0.08 to 1.2% by mass) with respect to the polymer solid content in the polyamic acid solution (about 05 to 2.5 μm). %) Containing polyamic acid solution and no lubricant or a small amount thereof (preferably less than 0.02% by mass, more preferably 0.01% by mass with respect to the polymer solid content in the polyamic acid solution). It can be produced by using two kinds of polyamic acid solutions (less than).

The multi-layered (laminated) method of the multi-layer condensed polymer film is not particularly limited as long as there is no problem in the adhesion between the two layers, and any method may be used as long as it adheres without interposing an adhesive layer or the like. ..

In the case of a polyimide film, for example, i) a method of producing one polyimide film and then continuously applying the other polyamic acid solution on the polyimide film for imidization, ii) casting the one polyamic acid solution. After preparing the polyimide film, the other polyimide solution is continuously applied onto the polyimide film and then imidized, iii) the method by co-extrusion, iv) the lubricant is not contained or the content thereof is high. Examples thereof include a method of applying a polyimide solution containing a large amount of lubricating material on a film formed of a small amount of polyimide solution by spray coating, T-die coating, or the like to imidize the film. In the present invention, it is preferable to use the methods i) to ii) above.

The ratio of the thickness of each layer in the multilayer condensed polymer film is not particularly limited, but the polymer layer containing a large amount of lubricant is the layer (a), and the polymer layer containing no lubricant or its content is small. When the polymer layer is the layer (b), the layer (a) / layer (b) is preferably 0.05 to 0.95. If the number of the (a) layer / (b) layer exceeds 0.95, the smoothness of the (b) layer tends to be lost, while if it is less than 0.05, the effect of improving the surface characteristics is insufficient and the slipperiness is lost. May be struck.

<Surface activation treatment of condensed polymer film>
It is preferable that the condensed polymer film used in the present invention is subjected to a surface activation treatment. By the surface activation treatment, the surface of the condensed polymer film is modified to a state in which functional groups are present (so-called activated state), and the adhesiveness to the silane coupling agent is improved.
The surface activation treatment in the present invention is a dry or wet surface treatment. As the dry treatment of the present invention, treatment of irradiating the surface with active energy rays such as ultraviolet rays, electron beams, and X-rays, corona treatment, vacuum plasma treatment, atmospheric pressure plasma treatment, flame treatment, and itro treatment can be used. .. As the wet treatment, a treatment in which the film surface is brought into contact with an acid or alkaline solution can be exemplified. The surface activation treatment preferably used in the present invention is a plasma treatment, which is a combination of a plasma treatment and a wet acid treatment.

The plasma treatment is not particularly limited, but includes RF plasma treatment in vacuum, microwave plasma treatment, microwave ECR plasma treatment, atmospheric pressure plasma treatment, corona treatment, etc., and gas treatment containing fluorine and ions. It also includes ion implantation treatment using a source, treatment using the PBII method, flame treatment exposed to thermal plasma, and itro treatment. Among these, RF plasma treatment in vacuum, microwave plasma treatment, and atmospheric pressure plasma treatment are preferable.

Suitable conditions for plasma treatment include oxygen plasma, plasma containing fluorine such as CF4 and C2F6, and plasma known to have a high chemical etching effect, or physical such as Ne, Ar, Kr, Xe, and plasma. It is desirable to use plasma, which has a high effect of physically etching by applying a large amount of energy to the surface of the polymer. It is also preferable to add plasma such as CO2, CO, H2, N2, NH4, CH4, a mixed gas thereof, and water vapor. In addition to these, OH, N2, N, CO, CO2, H, H2, O2, NH, NH2, NH3, COOH, NO, NO2, He, Ne, Ar, Kr, Xe, CH2O, Si (OCH3) 4, It is necessary to create a plasma containing at least one component selected from the group consisting of Si (OC2H5) 4, C3H7Si (OCH3) 3, and C3H7Si (OC2H5) 3 as a gas or as a decomposition product in plasma. When aiming for processing in a short time, plasma with high energy density, high kinetic energy of ions in plasma, and plasma with high number density of active species are desirable, but energy is required because surface smoothness is required. There is a limit to increasing the density. When oxygen plasma is used, surface oxidation progresses, which is good in terms of forming OH groups, but it is easy to form a surface that already has poor adhesion to the film itself, and the surface roughness (roughness) increases. Adhesion also deteriorates. In addition, in plasma using Ar gas, the effect of purely physical collision occurs on the surface, and in this case as well, the surface roughness becomes large. Considering these comprehensively, microwave plasma treatment, microwave ECR plasma treatment, plasma irradiation with an ion source that can easily shoot high-energy ions, PBII method, and the like are also desirable.

Such surface activation treatment cleans the polymer surface and produces more active functional groups. The generated functional group is bound to the coupling agent layer by a hydrogen bond or a chemical reaction, and the condensed polymer film layer and the coupling agent layer can be firmly adhered to each other.
In the plasma treatment, the effect of etching the surface of the condensed polymer film can also be obtained. In particular, in a condensed polymer film containing a relatively large amount of lubricant particles, protrusions due to the lubricant may hinder the adhesion between the film and the silicone resin. In this case, it is possible to remove the lubricant particles near the film surface by thinly etching the surface of the condensed polymer film by plasma treatment to expose some of the lubricant particles and then treating with phosphoric acid. Is.

The surface activation treatment may be applied to only one side of the condensed polymer film, or may be applied to both sides. When plasma treatment is performed on one side, the condensed polymer film is placed in contact with the electrode on one side by plasma treatment with the parallel plate type electrode, so that only the side of the condensed polymer film that is not in contact with the electrode is covered. Plasma treatment can be applied. Further, if the condensed polymer film is placed in a state of being electrically floated in the space between the two electrodes, plasma treatment can be performed on both surfaces. Further, single-sided treatment is possible by performing plasma treatment with a protective film attached to one side of the condensed polymer film. As the protective film, a PET film with an adhesive, an olefin film, or the like can be used.

<Silane coupling agent>
The silane coupling agent in the present invention refers to a compound that physically or chemically intervenes between a silicone resin and a condensed polymer film and has an action of enhancing the adhesive force between the two.
Preferred specific examples of the silane coupling agent include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, and N-2- ( Aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, 2- (3,4-Epoxycyclohexyl) Ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, vinyltricrolsilane, Vinyl trimethoxysilane, vinyl triethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycid Xypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-Acryloxipropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane , 3-Chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanpropyltriethoxysilane, tris- (3-trimethoxy) Cyrilpropyl) isocyanurate, chloromethylphenetyltrimethoxysilane, chloromethyltrimethoxysilane, aminophenyltrimethoxysilane, aminophenetyltrimethoxysilane, aminophenylaminomethylphenetyltrimethoxysilane, hexamethyldisilazane and the like.

In addition to the above, silane coupling agents that can be used in the present invention include n-propyltrimethoxysilane, butyltrichlorosilane, 2-cyanoethyltriethoxysilane, cyclohexyltrichlorosilane, decyltrichlorosilane, diacetoxydimethylsilane, and diacetoxydimethylsilane. Ethoxydimethylsilane, dimethoxydimethylsilane, dimethoxydiphenylsilane, dimethoxymethylphenylsilane, dodecyllichlorosilane, dodecyltrimethoxylane, ethyltrichlorosilane, hexyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrimethoxysilane, n-octyltrichlorosilane , N-octyltriethoxysilane, n-octyltrimethoxysilane, triethoxyethylsilane, triethoxymethylsilane, trimethoxymethylsilane, trimethoxyphenylsilane, pentyltriethoxysilane, pentyllichlorosilane, triacetoxymethylsilane, trichloro Hexylsilane, trichloromethylsilane, trichlorooctadecylsilane, trichloropropylsilane, trichlorotetradecylsilane, trimethoxypropylsilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, diethoxymethylvinylsilane, dimethoxymethylvinylsilane, trichlorovinylsilane , Triethoxyvinylsilane, vinyltris (2-methoxyethoxy) silane, trichloro-2-cyanoethylsilane, diethoxy (3-glycidyloxypropyl) methylsilane, 3-glycidyloxypropyl (dimethoxy) methylsilane, 3-glycidyloxypropyltrimethoxysilane, Etc. can also be used.

Further, other alkoxylans such as tetramethoxysilane and tetraethoxysilane may be appropriately added to the silane coupling agent.

In addition, mixing and heating operations are added to the silane coupling agent, including cases where other alkoxylans such as tetramethoxysilane and tetraethoxysilane are appropriately added or not added, to slightly react the reaction. You may use it after proceeding.

Among such silane coupling agents, the silane coupling agent preferably used in the present invention is preferably a silane coupling agent having a chemical structure having one silicon atom per molecule.
In the present invention, particularly preferable silane coupling agents include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, and N-2. -(Aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, aminophenyl Examples thereof include trimethoxysilane, aminophenyl trimethoxysilane, and aminophenyl aminomethylphenyl trimethoxysilane. When particularly high heat resistance is required in the process, it is desirable that Si and an amino group are connected by an aromatic group.
In the present invention, a phosphorus-based coupling agent, a titanate-based coupling agent, or the like may be used in combination, if necessary.

<Application method of silane coupling agent>
In the conventional technique, the application of the silane coupling agent is performed in a solution state in which the silane coupling agent is diluted with a solvent such as alcohol. However, the present invention is characterized in that this silane coupling agent coating step is performed via the gas phase. That is, the coating is performed by exposing the condensed polymer film to the vaporized silane coupling agent of the present invention. The application of the silane coupling agent may be paraphrased as the treatment of the silane coupling agent. Vaporization refers to the state in which the vapor of the silane coupling agent, that is, the silane coupling agent in a substantially gaseous state or the silane coupling agent in a fine particle state is present. The exposure means that the condensed polymer film is in contact with the gas containing the vaporized silane coupling agent or a vacuum state.

The vapor of the silane coupling agent can be easily obtained by heating the liquid silane coupling agent to a temperature from 40 ° C. to the boiling point of the silane coupling agent. The above silane coupling agent is produced even if it is below the boiling point. A state in which fine particles of the silane coupling agent coexist can also be used. Further, the steam density may be increased by manipulating the temperature and pressure. The boiling point of the silane coupling agent varies depending on the chemical structure, but is generally in the range of 100 to 250 ° C. However, heating at 200 ° C. or higher is not preferable because it may cause a side reaction on the organic group side of the silane coupling agent.

The environment for heating the silane coupling agent may be any of pressure, normal pressure, and reduced pressure, but in the case of promoting vaporization of the silane coupling agent, it is generally preferable to use normal pressure or reduced pressure. Since the silane coupling agent is often classified as a flammable liquid, it is preferable to carry out the vaporization work in a closed container, preferably after replacing the inside of the container with an inert gas.
On the other hand, from the viewpoint of improving production efficiency and reducing the price of production equipment, it is desirable to apply a silane coupling agent in an environment that does not use vacuum. For example, a condensed polymer film is set in the chamber under normal pressure, the inside of the chamber is filled with a carrier gas at substantially normal pressure containing a silane coupling agent vaporized, and the silane coupling agent is deposited, and then vaporized again. It can be carried out at approximately atmospheric pressure until the state without the silane coupling agent is returned.

The time for exposing the condensed polymer film to the vaporized silane coupling agent is not particularly limited, but is within 20 hours, preferably within 60 minutes, more preferably within 15 minutes, and even more preferably within 1 minute.
The temperature of the condensed polymer film during exposure of the condensed polymer film to the vaporized silane coupling agent is -50 ° C to 200 ° C depending on the type of the silane coupling agent and the desired thickness of the silane coupling agent layer. It is preferable to control the temperature between them.

The condensed polymer film exposed to the vaporized silane coupling agent is preferably heated to 70 ° C. to 200 ° C., more preferably 75 ° C. to 150 ° C. after exposure. By such heating, the hydroxyl group on the surface of the condensed polymer film reacts with the alkoxy group or the silazane group of the silane coupling agent, and the silane coupling agent treatment is completed. The time required for heating is 10 seconds or more and 10 minutes or less. If the temperature is too high or the time is too long, the coupling agent may deteriorate. If it is too short, the processing effect cannot be obtained. If the substrate temperature during exposure to the silane coupling agent is already 80 ° C. or higher, the subsequent heating can be omitted. The heating temperature or time depends on the heat resistance of the condensed polymer film. In order to increase the degree of freedom in the conditions of such treatment, it is preferable to use a condensed polymer film having high heat resistance.

In addition, when introducing a gas containing a vaporized silane coupling agent into a room where the polymer substrate is exposed, once the gas is separated into two or more and introduced, the two or more gases collide in the room. It is also effective to generate a turbulent flow by causing the silane coupling agent to be distributed uniformly.
As a method for vaporizing the silane coupling agent, in addition to evaporative vaporization by heating, a method of introducing a gas into the silane coupling agent liquid to generate bubbles is also preferable. This is hereafter referred to as bubbling. For bubbling, simply put a pipe through which gas passes into a silane coupling agent solution, attach a porous body to the tip of the pipe so that many fine bubbles are emitted, and vaporize by superimposing ultrasonic waves. What encourages is also effective.
In addition, many vaporized silane coupling agents are charged, and many silane coupling agents can be deposited in a short time by applying an electric field to the condensed polymer film at the time of exposure, and the silane coupling agents move. Since it has energy, it is possible to prevent the sedimentary film from becoming an island-like film. Further, it is known that when the carrier gas used contains water, the reaction between the water and the silane coupling agent starts. Therefore, it is effective that the dew point is low. Desirably, the dew point is 15 ° C. or lower, more preferably 10 ° C. or lower, and even more preferably 5 ° C. or lower.

Further, in the present invention, if the dew point of the carrier gas is set to 0 ° C. or lower to highly suppress the reaction between the water content and the silane coupling agent, the silane coupling in a state where the film thickness of the deposited film at the initial stage of deposition is non-uniform. Since the agent reaction is suppressed, and as a result, the reaction occurs uniformly after the film thickness of the deposited film reaches sufficiently uniform, extremely fine irregularities on the surface are suppressed, and an extremely smooth surface state can be realized. ..

The following methods can be specifically exemplified as a method for applying the silane coupling agent.
-A method of forming a silane coupling agent layer by exposing a condensed polymer film to a silane coupling agent vaporized by a bubbling method.
A method in which a dry gas having a dew point of 0 ° C. or lower is used as a carrier gas in a step of forming a silane coupling agent layer by exposing a condensed polymer film to a vaporized silane coupling agent.
-A method in which a gas having a dew point of 5 ° C or higher coexists in a step of forming a silane coupling agent layer by exposing a condensed polymer film to a vaporized silane coupling agent.
A method of applying an electric field to the condensed polymer film in a step of forming a silane coupling agent layer by exposing the condensed polymer film to a vaporized silane coupling agent.
-A method of activating the surface of the condensation polymer film on which the silane coupling agent layer is formed before forming the silane coupling agent layer.

The number of silicon-containing foreign substances having a major axis of 10 μm or more present in the silane coupling agent layer of the organic condensation polymer film / silicone resin polymer composite film is 2000 / m ² or less, preferably 1000 / m ² or less, and further. A preferred embodiment of the present invention is 500 pieces / m ² or less. Further, the number of silicon-containing foreign substances can be achieved by combining the above operations.

Theoretically, one molecular layer is sufficient for the coating amount and thickness of the coupling agent, and a thickness that can be ignored in terms of mechanical design is sufficient. Generally, it is less than 200 nm (less than 0.2 μm), preferably 150 nm or less (0.15 μm or less), more preferably 100 nm or less (0.1 μm or less), more preferably 50 nm or less, still more preferably. It is 10 nm or less. However, in the calculation, when the region is 5 nm or less, it is assumed that the coupling agent exists in a cluster form rather than as a uniform coating film, which is not very preferable. The silane coupling agent layer needs to be in close contact with the silicone resin for adhesion. Since solids come into contact with each other rather than through a liquid or a flexible layer, adhesion cannot be achieved without first contact. Although the film is flexible, it cannot follow the fine surface roughness, so the surface roughness needs to be 5.0 nm or less, preferably 3.0 nm or less, and more preferably 1.0 nm or less. Good.
The film thickness of the coupling agent layer can be calculated from the concentration and coating amount of the coupling agent solution at the time of incineration analysis by ellipsometry method, fluorescent X-ray method, ICP method or coating.

<Polymer composite film manufacturing method>
In the present invention, a liquid dimethylsiloxane resin is applied to the silane coupling agent layer side of the condensation polymer film on which the silane coupling agent layer is formed, and then the condensation polymer is cured and solidified by a chemical reaction. A polymer composite film of a film and a silicone resin can be obtained.
Curing of a silicone resin is mainly due to high molecular weight and cross-linking due to a dehydration reaction or a dealcoholization reaction between a hydroxyl group (-OH) and a methoxy group (-OCH3) or hydroxyl groups. Normally, this reaction occurs at 200 ° C. to 250 ° C., but it can be reduced by using a curing catalyst or modifying the silicone resin.
For coating the liquid silicone resin, known coating methods such as spin coating, dip coating, bar coating, applicator Daiko, comma coater, screen printing gravure printing, capillary coating, and spray coating can be used. The thickness of the silicone resin in the present invention is preferably 0.5 μm to 10 mm, more preferably 2 μm to 3 mm, and still more preferably 5 μm or more and 500 μm or less.
Further, in the present invention, a polymer composite film can also be obtained by activating the surface of a silicone resin film or sheet, superimposing it on a silane coupling agent-coated condensed polymer film, and heating and pressurizing it. At this time, it is preferable that unreacted groups remain in the silicone resin. In other words, a polymer composite film can be efficiently obtained by using a silicone resin in the B stage state. As a method of heating and pressurizing, a roll laminating method, a pressing method, or the like can be used, and it is preferable to use a vacuum pressing device in order to obtain a precise polymer composite film without blisters or the like.

In the present invention, the peel strength between the silicone resin layer and the polymer film is 0.3 N / cm or more and 15 N / cm or less. The peel strength is preferably 0.4 N / cm or more and 12 N / cm or less, more preferably 0.7 N / cm or more and 10 N / cm or less, and preferably 1.5 N / cm or more and 8 N / cm or less. The peel strength between the silicone resin layer and the polymer film can be controlled by the surface treatment of the polymer film, the coating conditions of the silane coupling agent, the coating amount, the coating film thickness, and the lamination conditions. A particularly important parameter is the thickness of the silane coupling agent, and by setting the thickness of the silane coupling agent layer to 40 nm or less, the peel strength can be controlled within a predetermined range.

<Application fields of polymer composite films>
The polymer composite film of the present invention exhibits excellent properties that combine the flexibility, heat resistance, electrical properties, and chemical durability of a silicone resin with the rigidity of a condensed polymer film.
A polymer composite film in which silicone resins are arranged on both sides of a condensed polymer film having good heat resistance and dimensional stability is a high-frequency circuit board and a high-frequency antenna substrate in order to achieve both good electrical characteristics and good dimensional stability. Can be applied as.
A seamless pipe or seamless belt in which a condensed polymer film is formed into a seamless pipe or seamless belt and a silicone resin layer is formed on the surface thereof is a fixing belt or electrostatic image of a toner image of a laser printer or the like. It is useful as a carrier belt for transporting and stacking.
When the polymer composite film of the present invention is used as a cushioning material during pressing, both good cushioning in the thickness direction and rigidity in the surface direction are achieved, and there is no unevenness in the surface direction unlike a fiber reinforced concrete body. Therefore, a very delicate and good pressed product can be obtained.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. The evaluation method of physical properties in the following examples is as follows.
1. 1. Reducing viscosity of polyamic acid (ηsp / C)
A solution dissolved in N-methyl-2-pyrrolidone (or N, N-dimethylacetamide) so that the polymer concentration was 0.2 g / dl was measured at 30 ° C. using an Ubbelohde type viscosity tube. (When the solvent used to prepare the polyamic acid solution was N, N-dimethylacetamide, the polymer was dissolved using N, N-dimethylacetamide and measured.)

2. The thickness of a polymer film or the like was measured using a micrometer (Millitron 1245D manufactured by Finereuf).
3. 3. Tension elastic modulus, tensile breaking strength and tensile breaking elongation of the polymer film The polyimide film to be measured is cut into strips of 100 mm × 10 mm in the flow direction (MD direction) and width direction (TD direction), respectively, and tested. I made a piece. Using a tensile tester (manufactured by Shimadzu Corporation, Autograph (R) model name AG-5000A), the tensile elastic modulus and tensile fracture in each of the MD and TD directions under the conditions of a tensile speed of 50 mm / min and a chuck distance of 40 mm. The strength and tensile modulus at break were measured.

4. 90-degree peel strength According to the 90-degree peeling method of JISK6854-1, the adhesive strength between the layer made of a condensed polymer of a polymer composite film and the layer made of polydimethylsiloxane was determined. Specifically, each is bonded using a two-component RTV silicone rubber KE-1800T-A / B manufactured by Shinetsu Chemical Industry Co., Ltd. so that it becomes a polyimide film / obtained polymer composite film / glass plate. Then, the glass plate was fixed to a 90-degree peeling measuring jig, and the polyimide film was pulled up so that the peeling interface became the interface between the polydimethylsiloxane layer and the condensed polymer film layer, and the peeling strength was determined.
Device name; Autograph AG-IS manufactured by Shimadzu Corporation
Measurement temperature; Room temperature peeling speed; 50 mm / min
Atmosphere; Atmosphere measurement sample width; 1 cm

5. Coefficient of linear expansion (CTE)
The expansion and contraction ratio of the polymer film to be measured was measured in the flow direction (MD direction) and width direction (TD direction) under the following conditions, and the temperature was 30 ° C to 45 ° C, 45 ° C to 60 ° C, ... And 15 ° C. The expansion / contraction rate / temperature at intervals was measured, this measurement was performed up to 300 ° C., and the average value of all the measured values was calculated as CTE.
Device name; TMA4000S manufactured by MAC Science
Sample length; 20 mm
Sample width; 2 mm
Temperature rise start temperature; 25 ° C
Temperature rise end temperature; 400 ° C
Heating rate; 5 ° C / min
Atmosphere; Argon initial load; 34.5 g / mm2

6. Average particle size of inorganic particles The inorganic particles to be measured were dispersed in a solvent as described later, and the particle size distribution was obtained with a laser scattering type particle size distribution meter LB-500 manufactured by Horiba Seisakusho Co., Ltd., and the weight (volume) average particle size was obtained. The CV value was calculated.

7. 7. Method for measuring the thickness of the coupling agent layer The thickness of the coupling layer was measured by measuring the film thickness produced on the Si wafer.
The film thickness was measured by ellipsometry, and the measuring instrument was FE-5000 manufactured by Photal.
The hardware specifications of this measuring instrument are as follows.
Reflection angle range 45 to 80 °, wavelength range 250 to 800 nm, wavelength resolution 1.25 nm, spot diameter 1 mm, tanΨ measurement accuracy ± 0.01, cosΔ measurement accuracy ± 0.01, method rotary analyzer method. The deflection element angle was 45 °, the incident angle was fixed at 70 °, and the analyzer measured 0 to 360 ° and 250 to 800 nm in 11.25 ° increments.
The film thickness was determined by fitting by the nonlinear least squares method. At this time, the model is an Air / thin film / Si model.
n = C3 / λ4 + C2 / λ2 + C1
k = C6 / λ4 + C5 / λ2 + C4
Wavelength-dependent C1 to C6 were obtained by the formula of.

8. Evaluation of polymer film: Roll winding property When a long multilayer polyimide film is wound on a winding roll (outer diameter of mandrel: 15 cm) at a speed of 2 m / min, wrinkles do not occur and the film is smoothly wound. The case where the film can be taken is marked with ◯, the case where the film is partially wrinkled is marked with Δ, and the case where the film is wrinkled or wound around the roll and cannot be smoothly wound is marked with x.

9. Dry nitrogen In this example, when described as dry nitrogen, nitrogen with a dew point of -10 ° C or less was used. The purity of nitrogen was 99.9% or more.

10. Polymer film surface roughness The surface roughness of the condensed polymer film in the table of this example indicates the three-dimensional surface roughness Sa after the silane coupling agent is applied to the condensed polymer film.

11. The three-dimensional arithmetic mean roughness (Sa) of the SC layer was determined using a non-contact surface / layer cross-sectional shape measurement system (“VertScan R2.0” manufactured by Ryoka System Co., Ltd.). The measurement was performed under the following conditions.
Measurement mode: Phase mode Field size: 640 x 480
Filter used: 520nm filter Objective lens magnification: × 5
Zoom lens magnification: × 1
Measurement range for each measurement: 1.4 mm x 1.8 mm
Number of integrations: 1 times For the raw data obtained under the above conditions, only the 4th-order surface correction was performed without performing interpolation to obtain measurement data. It was calculated from this measurement data based on the following formula.

(lx, ly are the range in the x and y directions, respectively, Z (x, y) is the height from the average plane)

<Foreign matter density>
A 100 mm x 100 mm area is sampled, the sampled area is observed with a microscope with a length measuring function of 100 times magnification, and for foreign substances confirmed by 100 times observation, the major axis length is measured with a further magnification of 400 times. Then, the number of objects of 10 μm or more was counted and divided by the observation area to obtain the foreign matter density. The unit of foreign matter density is (pieces / m2).

<Appearance quality>
Visually observe the appearance of the film, and if there are no defects such as scratches, wrinkles, flatness (waviness), etc., ◎, defects are found in one minute, but by slitting to a width of 300 mm, the defects can be removed. When it was possible to avoid it, it was marked with ◯, when it was possible to avoid the defect by slitting it to 150 mm, it was marked with Δ, and when it was not possible to avoid the defect visually recognizable by the slit, it was marked with ×.

[Manufacturing Examples 1 and 2]
(Preparation of polyamic acid solutions A1 to A2)
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod with nitrogen, 223 parts by mass of 5-amino-2- (p-aminophenyl) benzoxazole and 4416 parts by mass of N, N-dimethylacetamide were added. 217 parts by mass of pyromellitic dianhydride and colloidal silica dispersed in dimethylacetamide (DMAC-ST30, manufactured by Nissan Chemical Industries, Ltd.) so that the amount of silica in Table 1 is reached. In addition, stirring at a reaction temperature of 25 ° C. for 24 hours gave brown and viscous polyamic acid solutions A1 to A2.

[Manufacturing Examples 3 to 4]
(Preparation of polyamic acid solutions B1 to B2)
After nitrogen substitution in the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod, 3,3', 4,4'-biphenyltetracarboxylic dianhydride 398 parts by mass as tetracarboxylic dianhydride, para Snowtex (DMAC-ST30, manufactured by Nissan Chemical Industries, Ltd.), which is obtained by dissolving 147 parts by mass of phenylenediamine in 4600 parts by mass of N, N-dimethylacetamide and dispersing colloidal silica in dimethylacetamide, has silica in the amount shown in Table 2. When the mixture was stirred at a reaction temperature of 25 ° C. for 24 hours, brown and viscous polyamic acid solutions B1 to B2 were obtained.

<< Production Example 1 of Condensation Polymer Film >>
The polyamic acid solution A1 was coated on the non-slip material surface of the polyethylene terephthalate film A-4100 (manufactured by Toyobo Co., Ltd.) using a comma coater, dried at 110 ° C. for 5 minutes, and then not peeled off from the support. The polyamic acid film was wound up.
The obtained polyamic acid film is attached to the unwinding part of the film forming machine and passed through a pin tenter having three heat treatment zones, and the first stage is 150 ° C. × 2 minutes, the second stage is 220 ° C. × 2 minutes, and the third stage is 475 ° C. ×. The heat treatment was carried out for 4 minutes and slit to a width of 500 mm to obtain a polyimide film 1. The characteristics of the obtained polyimide film 1 are shown in Table 3.

<< Production Example 2 of Condensation Polymer Film >>
The polyamic acid solution A1 was coated on the non-slip material surface of the polyethylene terephthalate film A-4100 (manufactured by Toyobo Co., Ltd.) using a comma coater, dried at 110 ° C. for 5 minutes, and then not peeled off from the support. The polyamic acid film was wound up.
The obtained polyamic acid film is attached to the unwinding portion of the film-making machine, and the above-mentioned polyamic acid solution A2 is coated with the polyamic acid solution A1 in a thickness ratio shown in Table 3 using a comma coater. The surface of the acid film was coated and dried at 110 ° C. for 20 minutes to obtain a polyamic acid film having a two-layer structure. The coating thickness was adjusted so that the thickness of the entire two layers would be the thickness shown in Table 3 after the heat treatment.
This multilayer polyamic acid film is passed through a pin tenter having three heat treatment zones, and heat treatment is performed for the first stage 150 ° C. × 2 minutes, the second stage 220 ° C. × 2 minutes, and the third stage 475 ° C. × 4 minutes, and slits to a width of 500 mm. Then, the multilayer polyimide film 2 was obtained. At this time, as a non-polyimide protective film that can be peeled off after heat treatment and before winding, a film (film A) having a slightly adhesive layer was laminated on the polyamic acid solution A1 side, and then wound. The obtained polyimide film was designated as film 2. The characteristics of this polyimide film are shown in Table 3.

<< Production Example 3 of Condensation Polymer Film >>
A film 3 was obtained in exactly the same manner as in Production Example 1 except that the coating thicknesses of the polyamic acid solutions B1 and B2 were set to the values shown in Table 3. The contents are shown in Table 3 in the same manner as in Production Example 1.

As the condensation polymer film 4, a polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) having a thickness of 12.5 μm was used.

<Plasma treatment of condensed polymer film>
Both sides of the obtained condensed polymer film were subjected to vacuum plasma treatment to obtain a plasma-treated polyimide film. As the vacuum plasma processing, RIE mode using parallel plate type electrodes and processing by RF plasma are adopted, nitrogen gas is introduced into the vacuum chamber, and high frequency power of 13.54 MHz is introduced, and the processing time is It was set to 3 minutes.

<Formation of coupling agent layer on condensed polymer film>
Using a vacuum chamber having a hot plate, the silane coupling agent was applied to the condensed polymer film under the following conditions.
A petri dish was filled with 100 parts by mass of a silane coupling agent (“KBM-903” manufactured by Shin-Etsu Chemical Co., Ltd .: 3-aminopropyltrimethoxysilane) and allowed to stand on a hot plate. At this time, the hot plate temperature was 25 ° C. Next, a 350 mm × 490 mm condensed polymer film was fixed to the SUS frame and held vertically at a location 100 mm or more horizontally away from the liquid surface of the silane coupling agent, the vacuum chamber was closed, and vacuuming and nitrogen were applied. The introduction was repeated several times at atmospheric pressure until the oxygen concentration became 0.1% or less, then the inside of the chamber was depressurized to 3 × 10-1 Pa, the hot plate temperature was raised to 60 ° C., and 10 Hold for minutes to expose to silane coupling agent vapor, then lower the hot plate temperature, and at the same time gently introduce clean dry nitrogen gas into the vacuum chamber from 4 locations to return to atmospheric pressure and frame. The fixed condensed polymer film was taken out and held in a hot plate at 100 ° C. together with the SUS frame in a clean environment. Due to the thickness of the SUS frame, the condensed polymer film is heated at a distance of about 3 mm from the hot plate surface of the hot plate. After heat treatment for about 3 minutes, the same operation was performed on the back side to obtain a condensation polymer film S1 having silane coupling agent layers formed on both sides of the condensation polymer film.

<Formation of polydimethylsiloxane layer on condensed polymer film>
A two-component curable silicone resin SIM-260 manufactured by Shin-Etsu Chemical Co., Ltd. was applied to the silane coupling agent-coated surface of the obtained condensing polymer film with a silane coupling agent layer using an applicator, and the temperature was 30 ° C. Heat-treat the minutes, and then apply and heat-treat the back side in the same way. The polymer composite film shown in the above was obtained. The ratio of the main agent to the curing agent was set to 10/1 by mass ratio. Hereinafter, the coating conditions were changed from those of the condensed polymer film to obtain the laminated composite film shown in Table 4.

As described above, according to the present invention, it is possible to obtain a thin polymer composite film in which a condensed polymer film having excellent mechanical properties is used as a core material and the surface is coated with a silicone resin. Silicone resin has low mechanical strength due to its flexibility, and it is difficult to obtain an ultra-thin film. However, according to the present invention, an engineering film having excellent mechanical strength while having the special surface properties of silicone resin. It is possible to obtain a composite film having special properties that can be handled as described above. The polymer composite film of the present invention is used as a support material such as a cushioning agent for precision presses, as a substrate for electronic components such as high-frequency circuit boards, and a heat-fixed image-like fixing machine and image transfer that require high overlay accuracy. It can be applied as a belt, etc., and makes a great contribution to industry in the fields of information electronics and precision machining.

Claims (4)

A polymer composite consisting of at least a layer made of a resin containing polydimethylsiloxane as a main component, a silane coupling agent layer, and a layer made of a condensation polymer, and having a total thickness of 1 μm or more and 20 μm or less. the film. In a condensation polymer film having a layer made of a resin containing polydimethylsiloxane as a main component on both sides, a silane coupling agent is used between the layer made of a resin containing polydimethylsiloxane as a main component and the condensation polymer film. A polymer composite film having a layer and having a total thickness of 1 μm or more and 20 μm or less. The polymer composite film according to claim 1 or 2, wherein the condensed polymer film is a polyester film. The polymer composite film according to claim 1 or 2, wherein the condensed polymer film is a polyimide film.