JP6279689B2 - Near-infrared cut filter and method for producing near-infrared cut filter - Google Patents

Description

  The present invention relates to a near-infrared cut filter and a method for producing a near-infrared cut filter. More specifically, the present invention relates to a near-infrared cut filter having a structure in which a dielectric multilayer film is laminated on a polyimide resin film, and particularly suitable as a visibility correction filter for a solid-state imaging device such as a CCD or CMOS.

  In recent years, televisions equipped with plasma display panels (PDPs) have been commercialized and have become widespread in ordinary households. This PDP is a display that operates using plasma discharge, but it is known that near infrared rays (wavelength: 800 to 1,000 nm) are generated during plasma discharge.

  On the other hand, in homes, near-infrared rays are often used for remote control of home appliances such as TVs, stereos or air conditioners, and also for information exchange by personal computers. It has always been pointed out that it is likely to cause malfunctions.

Therefore, many of the commercially available PDPs are provided with a filter function for cutting near infrared rays emitted from the front plate.
In addition, CCDs and CMOS image sensors, which are solid-state image pickup devices for color images, are used in video cameras, digital still cameras, mobile phones with camera functions, etc., and these solid-state image pickup devices are sensitive to near-infrared light at their light receiving parts. Therefore, it is necessary to perform visibility correction, and a near-infrared cut filter is often used.

  As a near-infrared cut filter, what was conventionally manufactured by various methods is used. For example, a metal such as silver deposited on the surface of a transparent substrate such as glass to reflect near infrared rays, or a transparent substrate such as glass, acrylic resin or polycarbonate resin with a near infrared absorbing dye added Etc. are provided for practical use.

  However, the near-infrared cut filter in which metal is vapor-deposited on a glass base material is not only expensive to manufacture, but the glass piece of the base material is mixed as a foreign substance or a crack occurs during cutting (at the time of punching). There was a problem. On the other hand, a near-infrared cut filter using a resin film as a base material is also known (for example, see Patent Document 1). However, there is a problem that a manufacturing cost is required because functional films are laminated. Further, when a resin film is used as a base material, the heat resistance is inferior to that of a glass substrate at a high temperature, so that there is a problem that the substrate expands and contracts, thereby causing cracks in the near-infrared reflective film. Then, it is examined that a glass filler is contained in the resin film (Patent Document 2).

JP 2006-30944 A JP 2009-258362 A

In recent years, solid-state imaging devices have been reduced in size and height, and near-infrared cut filters are also required to be thinner. However, when the inventor of the present application examined the above Patent Document 2 (Japanese Unexamined Patent Publication No. 2009-258362), sufficient characteristics were not obtained in terms of heat resistance and spectral characteristics as the film thickness was reduced.
The object of the present invention is to solve the above-mentioned problems, and it is an object of the present invention to provide a thin near-infrared cut filter that is excellent in heat resistance and spectral characteristics.

  As a result of inventor's earnest study under the above-mentioned problems, by using a polyimide resin film as a base material, heat resistance can be cleared even if the base material is thin, and further, spectral characteristics are remarkably improved. The headline and the present invention were completed. Specifically, the above problem has been solved by the following means.

(1) A near-infrared cut filter having a near-infrared reflective film comprising a polyimide resin film and a dielectric multilayer film, and having a thickness of 80 μm or less.
(2) The near infrared cut filter according to (1), wherein the polyimide resin film contains a near infrared absorber.
(3) The near infrared cut filter according to (1) or (2), wherein the dielectric multilayer film has a structure in which low refractive index layers and high refractive index layers are alternately laminated.
(4) The polyimide resin film according to any one of (1) to (3), wherein the polyimide resin film includes a polymer having a repeating unit represented by the following general formula (1) and / or general formula (2). Near-infrared cut filter.
General formula (1)
(In general formula (1), R ¹ represents a tetravalent organic group. A plurality of R ¹ may be the same or different from each other. R ² represents a divalent organic group. R ² may be the same as or different from each other, provided that at least one of the plurality of R ² is a group having an alicyclic group, and R ³ represents a hydrogen atom or an organic group, respectively. )
General formula (2)
(In the general formula, X and Y each contain a monocyclic or condensed polycyclic aliphatic group or a monocyclic or condensed polycyclic aromatic group, and have 4 carbon atoms. Represents a linking group of ˜30.)
(5) The polyimide resin film is a polymer having a repeating unit represented by the general formula (2), and at least one of X and Y in the general formula (2) is monocyclic or condensed polycyclic The near-infrared cut filter according to (4), which contains a polymer that is an aliphatic group.
(6) The polyimide resin film is a polymer having a repeating unit represented by the general formula (2), wherein X in the general formula (2) is an aromatic group, and Y is monocyclic or condensed poly The near-infrared cut filter according to (4), comprising a polymer that is a cyclic aliphatic group.
(7) One of the low refractive index layers includes silica (SiO ₂ ), and one of the high refractive index layers includes titania (TiO ₂ ), according to any one of (3) to (6). Near-infrared cut filter.
(8) One of the low refractive index layers contains silica (SiO ₂ ), and the high refractive index layer contains either ITO (tin-doped indium oxide) or ATO (antimony-doped tin oxide). The near-infrared cut filter according to any one of (6).
(9) The near-infrared cut filter according to any one of (1) to (8), wherein the polyimide resin film has a thickness of 60 μm or less.
(10) A solid-state imaging device using the near-infrared cut filter according to any one of (1) to (9).
(11) A method for producing a near-infrared cut filter, comprising forming a near-infrared reflective film made of a dielectric multilayer film on a polyimide resin film having a thickness of 80 μm or less by vapor deposition.
(12) The manufacturing method of the near-infrared cut filter as described in (11) whose substrate temperature at the time of vapor deposition is 120-300 degreeC.

  According to the present invention, it is possible to provide a near-infrared cut filter that is thin and excellent in heat resistance and spectral characteristics. Moreover, since the near-infrared cut filter of this invention can form a dielectric multilayer film by vapor deposition, it can also reduce manufacturing cost.

  Hereinafter, the contents of the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

  The near-infrared cut filter of the present invention has a near-infrared reflective film composed of a polyimide resin film and a dielectric multilayer film, and the polyimide resin film has a thickness of 80 μm or less.

<Polyimide resin film>
The polyimide resin film used in the present invention has a thickness of 80 μm or less, and more preferably 60 μm or less. By setting it as such a range, it becomes possible to improve a spectral characteristic notably. Although the lower limit of the thickness of the polyimide resin film is not particularly defined, it can be set to, for example, 10 μm or more. The polyimide resin film may be composed of one layer or may be composed of two or more layers.

Next, the polyimide resin used in the present invention will be described.
The polyimide resin used in the present invention is not particularly defined, and known polyimide resins can be widely used. In the present invention, a polymer having a repeating unit represented by the following general formula (1) and / or general formula (2) is preferable.
General formula (1)
(In general formula (1), R ¹ represents a tetravalent organic group. A plurality of R ¹ may be the same or different from each other. R ² represents a divalent organic group. R ² may be the same as or different from each other, provided that at least one of the plurality of R ² is a group having an alicyclic group, and R ³ represents a hydrogen atom or an organic group, respectively. )

(A) Resin having a repeating unit of the general formula (1) The repeating unit represented by the general formula (1) includes the two carbonyl groups sandwiched between two carbonyl groups in the general formula (1). structure and acid component is composed of a general formula (1) -NH-R ² -NH- represented by partial structure a is a diamine component in.
The tetravalent organic group R ¹ preferably has 4 to 30 carbon atoms, and more preferably a tetravalent linking group having a monocyclic or condensed polycyclic aliphatic group or aromatic group. . A plurality of R ¹ present in the resin (a) may be the same or different.
Examples of the monocyclic aromatic group in the tetravalent organic group R ¹ include a benzene ring group and a pyridine ring group.
Examples of the condensed polycyclic aromatic group in the tetravalent organic group R ¹ include a naphthalene ring group and a perylene ring group.
Examples of the monocyclic aliphatic group in the tetravalent organic group R ¹ include a cyclobutane ring group, a cyclopentane ring group, and a cyclohexane ring group.
Examples of the condensed polycyclic aliphatic group in the tetravalent organic group R ¹ include a bicyclo [2.2.1] heptane ring group, a bicyclo [2.2.2] octane ring group, and a bicyclo [2.2. 2] An oct-7-ene ring group and the like can be mentioned.
As the tetravalent linking group having a monocyclic or condensed polycyclic aliphatic group or aromatic group for the tetravalent organic group R ¹ , the above-mentioned monocyclic or condensed polycyclic aliphatic group or The aromatic group itself may be used, but a plurality of monocyclic or condensed polycyclic aliphatic groups or aromatic groups are linked via a single bond or a divalent linking group, and 4 as R ¹ A valent linking group may be formed.
As the divalent linking group, an alkylene group (preferably an alkylene group having 1 to 6 carbon atoms, for example, a methylene group, an ethylene group, a propylene group, etc.), an oxygen atom, a sulfur atom, a divalent sulfone group, an ester bond. , Ketone group, amide group and the like.

Specific examples of the acid component having a group derived from at least four carboxyl groups with R ¹ as a nucleus include pyromellitic acid anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic acid anhydride, 2, 3,3 ′, 4′-biphenyltetracarboxylic anhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic anhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic anhydride, 2 , 2 ′, 3,3′-benzophenonetetracarboxylic anhydride, 4,4 ′-(hexafluoroisopropylidene) diphthalic anhydride, 1,2,5,6-naphthalenetetracarboxylic anhydride, 2, 3,6,7-naphthalenetetracarboxylic anhydride, 2,3,5,6-pyridinetetracarboxylic anhydride, 3,4,9,10-perylenetetracarboxylic anhydride, (trifluoromethyl) pyromellit Acid anhydride, di (trifluoromethyl) pyromellitic acid anhydride, di (heptafluoropropyl) pyromellitic acid anhydride, pentafluoroethylpyromellitic acid anhydride, bis [3,5-di (trifluoromethyl) phenoxy Pyromellitic anhydride, 3,3 ′, 4,4′-tetracarboxydiphenyl ether dianhydride, 2,3 ′, 3,4′-tetracarboxydiphenyl ether dianhydride, 3,3 ′, 4,4 '-Tetracarboxydiphenylmethane dianhydride, 3,3', 4,4'-tetracarboxydiphenylsulfone dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2- Bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 5,5′-bis (trifluoromethyl) -3,3 ′, 4,4′-tetraca Boxibiphenyl dianhydride, 2,2 ′, 5,5′-tetrakis (trifluoromethyl) -3,3 ′, 4,4′-tetracarboxybiphenyl dianhydride, 5,5′-bis (trifluoro Methyl) -3,3 ′, 4,4′-tetracarboxydiphenyl ether dianhydride, 5,5′-bis (trifluoromethyl) -3,3 ′, 4,4′-tetracarboxybenzophenone dianhydride, bis [(Trifluoromethyl) dicarboxyphenoxy] benzene dianhydride, bis (dicarboxyphenoxy) bis (trifluoromethyl) benzene dianhydride, bis (dicarboxyphenoxy) tetrakis (trifluoromethyl) benzene dianhydride, 2 , 2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 2,2-bis (4- (3,4-dicarboxy) Phenoxy) phenyl) hexafluoropropane dianhydride, 5,5 '- [p-phenylene bis (oxycarbonyl)] and component derived from an aromatic, such as di-phthalic anhydride tetracarboxylic acid anhydride,
Cyclobutanetetracarboxylic anhydride, cyclopentanetetracarboxylic anhydride, cyclohexanetetracarboxylic anhydride, 1,2,4,5-cyclohexanetetracarboxylic acid, bicyclo [2.2.1] heptane-2,3 5,6-tetracarboxylic acid, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic acid, or bicyclo [2.2.2] oct-7-ene-2,3,5 , 6-tetracarboxylic acid, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic dianhydride, (1S, 2S, 4R, 5R) -cyclohexanetetracarboxylic dianhydride, Examples include components derived from aliphatic tetracarboxylic anhydrides such as (1R, 2S, 4S, 5R) -cyclohexanetetracarboxylic dianhydride.

Preferably, a component derived from pyromellitic acid anhydride, a component derived from 3,3 ′, 4,4′-biphenyltetracarboxylic acid anhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic acid anhydride A component derived from 2,2 ′, 3,3′-biphenyltetracarboxylic anhydride, a component derived from 3,3 ′, 4,4′-benzophenonetetracarboxylic anhydride, 4,4 Component derived from '-(hexafluoroisopropylidene) diphthalic anhydride, component derived from 3,3', 4,4'-tetracarboxydiphenyl ether dianhydride, 1,2,5,6-naphthalenetetracarboxylic A component derived from an acid anhydride, a component derived from 5,5 ′-[p-phenylenebis (oxycarbonyl)] diphthalic anhydride, a component derived from cyclobutanetetracarboxylic anhydride, Component derived from tantetracarboxylic anhydride, component derived from bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic dianhydride, (1S, 2S, 4R, 5R)- A component derived from cyclohexanetetracarboxylic dianhydride, a component derived from (1R, 2S, 4S, 5R) -cyclohexanetetracarboxylic dianhydride, more preferably a component derived from pyromellitic acid anhydride, 3 , 3 ′, 4,4′-component derived from biphenyltetracarboxylic anhydride, component derived from 4,4 ′-(hexafluoroisopropylidene) diphthalic anhydride, derived from cyclobutanetetracarboxylic anhydride Component, component derived from 3,3 ′, 4,4′-tetracarboxydiphenyl ether dianhydride, component derived from cyclopentanetetracarboxylic anhydride A component derived from 5,5 ′-[p-phenylenebis (oxycarbonyl)] diphthalic anhydride, a component derived from (1S, 2S, 4R, 5R) -cyclohexanetetracarboxylic dianhydride, (1R, It is a component derived from 2S, 4S, 5R) -cyclohexanetetracarboxylic dianhydride. By using these, good solvent solubility, alkali dissolution rate, transparency, and stress characteristics can be realized.
The content of the acid component derived from the compound having four carboxyl groups with R ¹ as a nucleus in the resin (a) is 20 to 70 mol% with respect to all repeating units constituting the resin (a). It is preferable that it is 30 to 60 mol%.

Examples of the divalent organic group R ² include a divalent group having an alicyclic group, a divalent group having an aromatic group, and a divalent group containing a silicon atom. A plurality of R ² present in the resin (a) may be the same or different.
Hereinafter, the diamine component of the R ² at the core when the divalent group having a R ² are cycloaliphatic groups, sometimes called alicyclic diamine component, when R ² is a divalent group having an aromatic group the diamine component of R ² to the core of, sometimes called the aromatic diamine component, the diamine component of the R ² at the core when the divalent group R ² contains a silicon atom, that silicon diamine There is also.

At least one of R ^{2 in} the diamine component present in plural in the resin (a) is a divalent group having an alicyclic group. When the resin (a) contains a diamine component having an alicyclic group, good solvent solubility and transparency can be realized.
The alicyclic group that R ² may have is preferably a divalent alicyclic group having 3 to 20 carbon atoms, such as a monocyclic cycloalkylene group such as a cyclopentylene group or a cyclohexylene group, or bicyclo [2.2. 1] Polycyclic cycloalkylene groups such as a heptylene group, norbornylene group, tetracyclodecanylene group, tetracyclododecanylene group, adamantylene group, and the like can be given.
The divalent group having an alicyclic group for R ² may be the alicyclic group itself, but a plurality of alicyclic groups are alkylene groups (C1-C6 alkylene groups are preferred, Methylene group, ethylene group, propylene group, etc.) may be linked to form a divalent group having an alicyclic group as R ² , and the amino group and alicyclic group in the diamine component are alkylene groups. You may connect with.
The alicyclic group and alkylene group which can constitute a divalent group having an alicyclic group may have a substituent, and as such a substituent, an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms) ), Halogen atoms and the like.
Particularly preferred diamine components having an alicyclic structure having R ² as a nucleus include a 5-amino-1,3,3-trimethylcyclohexanemethylamine component, a cis-1,4-cyclohexanediamine component, and trans-1,4- Cyclohexanediamine component, 1,4-cyclohexanediamine component (cis, trans mixture), 4,4′-methylenebis (cyclohexylamine) component and its 3,3′-dimethyl-substituted product, bis (aminomethyl) bicyclo [2.2 .1] heptane component, 1,3-diaminoadamantane component, 3,3′-diamino-1,1′-biadamantyl component, 4,4′-hexafluoroisopropylidenebis (cyclohexylamine) component, Of which, 3,3′-diamino-1,1′-biadamantyl component, trans-1,4-cyclohe From the viewpoint of San diamine component to lower the stress.
The content of the alicyclic diamine component having two amino groups with R ² as a nucleus in the resin (a) is 20 to 70 mol% with respect to all repeating units constituting the resin (a). Preferably, it is 30-60 mol%.

The aromatic group in the divalent group having an aromatic group for R ² is preferably an aromatic group having 5 to 16 carbon atoms, and examples thereof include a phenylene group and a naphthylene group. Further, the aromatic group may contain a hetero atom such as a nitrogen atom or an oxygen atom, and examples thereof include a divalent benzoxazole group.
The divalent group having an aromatic group for R ² may be the aromatic group itself, but a plurality of aromatic groups are linked via a single bond or a divalent linking group, and R ² The divalent group which has an aromatic group as may be formed, and the amino group in the diamine component and the aromatic group may be linked via a divalent linking group.
As the divalent linking group, an alkylene group (preferably an alkylene group having 1 to 6 carbon atoms, for example, a methylene group, an ethylene group, a propylene group, etc.), an oxygen atom, a sulfur atom, a divalent sulfone group, an ester bond. , Ketone group, amide group and the like.
The aromatic group and alkylene group which can constitute a divalent group having an aromatic group may have a substituent, and as such a substituent, an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms) ), An alkoxy group such as a halogen atom and a methoxy group, and an aryl group such as a cyano group and a phenyl group.
Specific examples of the aromatic diamine component having R ² as a core include, for example, an m-phenylenediamine component, a p-phenylenediamine component, a 2,4-tolylenediamine component, a 3,3′-diaminodiphenyl ether component, 3, 4'-diaminodiphenyl ether component, 4,4'-diaminodiphenyl ether component, 3,3'-diaminodiphenyl sulfone component, 4,4'-diaminodiphenyl sulfone component, 3,4'-diaminodiphenyl sulfone component, 3,3 ' -Diaminodiphenylmethane component, 4,4'-diaminodiphenylmethane component, 3,4'-diaminodiphenylmethane component, 4,4'-diaminodiphenylsulfide component, 3,3'-diaminodiphenylketone component, 4,4'-diaminodiphenyl Ketone component, 3,4′-diaminodiphenyl ketone component, 2, '-Bis (4-aminophenyl) propane component, 2,2'-bis (4-aminophenyl) hexafluoropropane component, 1,3-bis (3-aminophenoxy) benzene component, 1,3-bis (4 -Aminophenoxy) benzene component, 1,4-bis (4-aminophenoxy) benzene component, 4-methyl-2,4-bis (4-aminophenyl) -1-pentene component, 4-methyl-2,4- Bis (4-aminophenyl) -2-pentene component, 1,4-bis (α, α-dimethyl-4-aminobenzyl) benzene component, imino-di-p-phenylenediamine component, 1,5-diaminonaphthalene component 2,6-diaminonaphthalene component, 4-methyl-2,4-bis (4-aminophenyl) pentane component, 5 (or 6) -amino-1- (4-aminophenyl) 1,3,3-trimethylindane component, bis (p-aminophenyl) phosphine oxide component, 4,4′-diaminoazobenzene component, 4,4′-diaminodiphenylurea component, 4,4′-bis (4-amino) Phenoxy) biphenyl component, 2,2-bis [4- (4-aminophenoxy) phenyl] propane component, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane component, 2,2-bis [4- (3-aminophenoxy) phenyl] benzophenone component, 4,4′-bis (4-aminophenoxy) diphenylsulfone component, 4,4′-bis [4- (α, α-dimethyl-4-aminobenzyl) ) Phenoxy] benzophenone component, 4,4′-bis [4- (α, α-dimethyl-4-aminobenzyl) phenoxy] diphenylsulfone 4,4′-diaminobiphenyl component, 4,4′-diaminobenzophenone component, phenylindanediamine component, 3,3′-dimethoxy-4,4′-diaminobiphenyl component, 3,3′-dimethyl-4, 4'-diaminobiphenyl component, 2,2'-dimethyl 4,4'-diaminobiphenyl component, 2,2'-bis (trifluoromethyl) benzidine component, o-toluidine sulfone component, 2,2-bis (4- Aminophenoxyphenyl) propane component, bis (4-aminophenoxyphenyl) sulfone component, bis (4-aminophenoxyphenyl) sulfide component, 1,4- (4-aminophenoxyphenyl) benzene component, 1,3- (4- Aminophenoxyphenyl) benzene component, 9,9-bis (4-aminophenyl) fluorene component, 4,4′-di (3-aminophenoxy) diphenylsulfone component, 4,4′-diaminobenzanilide component, 4-aminophenyl-4′-aminophenylbenzoate component, bis (4-aminophenyl) terephthalate component, 2- (4-aminophenyl) ) Benzoxazol-5-ylamine, 4,4 ″ -diamino-p-terphenyl component, etc., and the hydrogen atom of the aromatic nucleus of these aromatic diamines is a chlorine atom, a fluorine atom, a bromine atom, a methyl group, a methoxy group , A structure substituted with at least one group or atom selected from the group consisting of a cyano group and a phenyl group.
Particularly preferred aromatic diamine components include p-phenylenediamine component, 4,4′-diaminodiphenyl ether component, 3,3′-diaminodiphenylsulfone component, 4,4′-diaminodiphenylsulfone component, and 2,2′-bis. (4-aminophenyl) hexafluoropropane component, 1,4-bis (4-aminophenoxy) benzene component, imino-di-p-phenylenediamine component, 4,4′-diaminobiphenyl component, 4,4′-diamino Benzophenone component, 3,3′-dimethoxy-4,4′-diaminobiphenyl component, 3,3′-dimethyl-4,4′-diaminobiphenyl component, 2,2′-dimethyl 4,4′-diaminobiphenyl component, 2,2′-bis (trifluoromethyl) benzidine component, o-toluidine sulfone component, 2,2-bis (4-amino Nophenoxyphenyl) propane component, 9,9-bis (4-aminophenyl) fluorene component, 4,4′-di- (3-aminophenoxy) diphenylsulfone component, 4,4′-diaminobenzanilide component, 4- Aminophenyl-4′-aminophenylbenzoate component, bis (4-aminophenyl) terephthalate, 2- (4-aminophenyl) benzoxazol-5-ylamine component, 4,4 ″ -diamino-p-terphenyl component A film having good toughness and low stress can be obtained.
The diamine component may be substituted with a hydroxyl group. Examples of such bisaminophenol component include 3,3′-dihydroxybenzidine component, 3,3′-diamino-4,4′-dihydroxybiphenyl component, and 4,4′-diamino-3,3′-dihydroxy. Biphenyl component, 3,3′-diamino-4,4′-dihydroxydiphenylsulfone component, 4,4′-diamino-3,3′-dihydroxydiphenylsulfone component, bis- (3-amino-4-hydroxyphenyl) methane Component, 2,2-bis- (3-amino-4-hydroxyphenyl) propane component, 2,2-bis- (3-amino-4-hydroxyphenyl) hexafluoropropane component, 2,2-bis- (4 -Amino-3-hydroxyphenyl) hexafluoropropane component, bis- (4-amino-3-hydroxyphenyl) methane component, 2 2-bis- (4-amino-3-hydroxyphenyl) propane component, 4,4′-diamino-3,3′-dihydroxybenzophenone component, 3,3′-diamino-4,4′-dihydroxybenzophenone component, 4 , 4′-diamino-3,3′-dihydroxydiphenyl ether component, 3,3′-diamino-4,4′-dihydroxydiphenyl ether component, 1,4-diamino-2,5-dihydroxybenzene component, 1,3-diamino Examples include -2,4-dihydroxybenzene component and 1,3-diamino-4,6-dihydroxybenzene component. These bisaminophenol components may be used alone or in combination.

Among these bisaminophenol structures, a particularly preferred embodiment is that R ² in the general formula (1) is a divalent group having an aromatic group selected from the following.

In the above formula, X ₁ represents —O—, —S—, —C (CF ₃ ) ₂ —, —CH ₂ —, —SO ₂ —, —NHCO—. * Represents a bonding position with —NH— or —OH bonded to R ² in the general formula (1). In the above structure, —NH— and —OH bonded to R ² are bonded to each other in the ortho position (adjacent position).
The content of the aromatic diamine component having two amino groups with R ² as the nucleus in the resin (a) is 5 to 40 mol% with respect to all repeating units constituting the resin (a). Preferably, it is 10 to 30 mol%.

Further, the R ² in order to enhance the adhesion to the substrate can be a silicon diamine component as the diamine component to the nucleus. Examples include bis (4-aminophenyl) dimethylsilane component, bis (4-aminophenyl) tetramethylsiloxane component, bis (4-aminophenyl) tetramethyldisiloxane component, bis (γ-aminopropyl) tetramethyl. Examples thereof include a disiloxane component, a 1,4-bis (γ-aminopropyldimethylsilyl) benzene component, a bis (4-aminobutyl) tetramethyldisiloxane component, and a bis (γ-aminopropyl) tetraphenyldisiloxane component.
The following structure can also be mentioned as a silicon diamine component.

In the above formula, R ₅ and R ₆ represent a divalent organic group, and R ₇ and R ₈ represent a monovalent organic group. Several R < ₇ > may mutually be same or different. Several R < ₈ > may mutually be same or different.
Examples of the divalent organic group represented by R ₅ and R ₆ include an optionally substituted linear or branched alkylene group having 1 to 20 carbon atoms, a phenylene group having 6 to 20 carbon atoms, and carbon. This represents a divalent alicyclic group having a number of 3 to 20 or a group formed by combining these.
The monovalent organic group represented by R ₇ and R ₈ represents a linear or branched alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, which may have a substituent. .
More specifically, the following can be mentioned.

The content of the silicon diamine component having at least two amino groups with R ² as a nucleus in the resin (a) is 5 to 40 mol% with respect to all repeating units constituting the resin (a). Preferably, it is 10 to 30 mol%.

Examples of the organic group represented by R ³ preferably have 1 to 20 carbon atoms. Specifically, the alkyl group, cycloalkyl group, aryl group, aralkyl group, alkenyl group, alkynyl group, alkoxy group, silicon atom containing group, -CORc (Rc is an alkyl group, an aryl group, a cycloalkyl group), - SO ₂ Rd (Rd represents an alkyl group, an aryl group, a cycloalkyl group, o- quinonediazide group), or a group formed by combining them Can be mentioned.

The alkyl group represented by R ³ may have a substituent, and is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and an oxygen atom, sulfur atom, nitrogen atom in the alkyl chain You may have. Specifically, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-dodecyl group, n-tetradecyl group, n-octadecyl group And a branched alkyl group such as a linear alkyl group such as isopropyl group, isobutyl group, t-butyl group, neopentyl group, and 2-ethylhexyl group. Examples of the substituent include a cyano group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group.

The cycloalkyl group represented by R ³ may have a substituent, preferably a cycloalkyl group having 3 to 20 carbon atoms, may be polycyclic, and has an oxygen atom in the ring. Also good. Specific examples include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, an adamantyl group, and the like.

The aryl group represented by R ³ may have a substituent and is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group.

The aralkyl group represented by R ³ may have a substituent, and preferably an aralkyl group having 7 to 20 carbon atoms, for example, a benzyl group, a phenethyl group, a naphthylmethyl group, or a naphthylethyl group. Can be mentioned.

The alkoxy group represented by R ³ may have a substituent, preferably an alkoxy group having 1 to 20 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, A pentyloxy group, a hexyloxy group, a heptyloxy group, etc. are mentioned.

The silicon atom-containing group represented by R ³ is not particularly limited as long as silicon is contained, but a silyloxy group (trimethylsilyloxy, triethylsilyloxy, t-butyldimethylsilyloxy) is preferable.

Examples of the alkenyl group represented by R ³ include a group having a double bond at an arbitrary position of the alkyl group, cycloalkyl group, aryl group, aralkyl group, alkoxy group or silicon atom-containing group. C1-C12 is preferable and C1-C6 is more preferable. For example, a vinyl group and an allyl group are preferable.

Examples of the alkynyl group represented by R ³ include a group having a triple bond at an arbitrary position of the alkyl group, cycloalkyl group, aryl group, aralkyl group, alkoxy group, and silicon atom-containing group. C1-C12 is preferable and C1-C6 is more preferable. For example, an ethynyl group and a propargyl group are preferable.

In the present invention, a hydrogen atom and an organic group can be mixed in R ³ . It is preferable that it is 100 mol%-20 mol% with respect to all R < ³ > in resin (a), respectively, and it is more preferable that 100 mol%-40 mol% are organic groups.
Moreover, in this invention, terminal blocker can be made to react with the terminal of the polymer which has the repeating unit represented by General formula (1) as a main component. As the end-capping agent, monoamine, acid anhydride, monocarboxylic acid, monoacid chloride compound, monoactive ester compound and the like can be used. By making terminal blocker react, it is preferable at the point which can control the repeating number of a repeating unit, ie, molecular weight, in a preferable range. Furthermore, acid deactivation due to neutralization of the terminal amine and the generated acid can be suppressed by the terminal blocking agent. In addition, by reacting an end-capping agent at the terminal, various organic groups such as a crosslinking reactive group having a carbon-carbon unsaturated bond can be introduced as the terminal group.

  Monoamines used for the end capping agents are 5-amino-8-hydroxyquinoline, 4-amino-8-hydroxyquinoline, 1-hydroxy-8-aminonaphthalene, 1-hydroxy-7-aminonaphthalene, 1-hydroxy- 6-aminonaphthalene, 1-hydroxy-5-aminonaphthalene, 1-hydroxy-4-aminonaphthalene, 1-hydroxy-3-aminonaphthalene, 1-hydroxy-2-aminonaphthalene, 1-amino-7-hydroxynaphthalene, 2-hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene, 2-hydroxy-5-aminonaphthalene, 2-hydroxy-4-aminonaphthalene, 2-hydroxy-3-aminonaphthalene, 1-amino-2 -Hydroxynaphthalene, 1-carboxy-8-amino Phthalene, 1-carboxy-7-aminonaphthalene, 1-carboxy-6-aminonaphthalene, 1-carboxy-5-aminonaphthalene, 1-carboxy-4-aminonaphthalene, 1-carboxy-3-aminonaphthalene, 1-carboxy 2-aminonaphthalene, 1-amino-7-carboxynaphthalene, 2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-carboxy-4-aminonaphthalene 2-carboxy-3-aminonaphthalene, 1-amino-2-carboxynaphthalene, 2-aminonicotinic acid, 4-aminonicotinic acid, 5-aminonicotinic acid, 6-aminonicotinic acid, 4-aminosalicylic acid, 5- Aminosalicylic acid, 6-aminosalicylic acid, 3-a No-O-toluic acid, amelide, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, 2-aminobenzenesulfonic acid, 3-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid, 3-aminobenzene Amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-aminophenol, 4-aminophenol, 5-amino-8-mercaptoquinoline, 4-amino-8-mercaptoquinoline, 1-mercapto-8-aminonaphthalene 1-mercapto-7-aminonaphthalene, 1-mercapto-6-aminonaphthalene, 1-mercapto-5-aminonaphthalene, 1-mercapto-4-aminonaphthalene, 1-mercapto-3-aminonaphthalene, 1-mercapto- 2-aminonaphthalene, 1-amino-7-mercaptonaphthalene 2-mercapto-7-aminonaphthalene, 2-mercapto-6-aminonaphthalene, 2-mercapto-5-aminonaphthalene, 2-mercapto-4-aminonaphthalene, 2-mercapto-3-aminonaphthalene, 1-amino 2-mercaptonaphthalene, 3-amino-4,6-dimercaptopyrimidine, 2-aminothiophenol, 3-aminothiophenol, 4-aminothiophenol, 2-ethynylaniline, 3-ethynylaniline, 4-ethynylaniline 2,4-diethynylaniline, 2,5-diethynylaniline, 2,6-diethynylaniline, 3,4-diethynylaniline, 3,5-diethynylaniline, 1-ethynyl-2-aminonaphthalene, 1-ethynyl-3-aminonaphthalene, 1-ethynyl-4-aminonaphthalene 1-ethynyl-5-aminonaphthalene, 1-ethynyl-6-aminonaphthalene, 1-ethynyl-7-aminonaphthalene, 1-ethynyl-8-aminonaphthalene, 2-ethynyl-1-aminonaphthalene, 2-ethynyl-3 -Aminonaphthalene, 2-ethynyl-4-aminonaphthalene, 2-ethynyl-5-aminonaphthalene, 2-ethynyl-6-aminonaphthalene, 2-ethynyl-7-aminonaphthalene, 2-ethynyl-8-aminonaphthalene, 3 , 5-diethynyl-1-aminonaphthalene, 3,5-diethynyl-2-aminonaphthalene, 3,6-diethynyl-1-aminonaphthalene, 3,6-diethynyl-2-aminonaphthalene, 3,7-diethynyl-1 -Aminonaphthalene, 3,7-diethynyl-2-aminonaphthalene, 4,8-diethini 1-aminonaphthalene, 4,8-diethynyl-2-Amino-naphthalene, but it is not limited thereto.

  Of these, 5-amino-8-hydroxyquinoline, 1-hydroxy-7-aminonaphthalene, 1-hydroxy-6-aminonaphthalene, 1-hydroxy-5-aminonaphthalene, 1-hydroxy-4-aminonaphthalene, 2 -Hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene, 2-hydroxy-5-aminonaphthalene, 1-carboxy-7-aminonaphthalene, 1-carboxy-6-aminonaphthalene, 1-carboxy-5 Aminonaphthalene, 2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, 4- Aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid 2-aminobenzenesulfonic acid, 3-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid, 3-amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-aminophenol, 4-aminophenol, 2- Aminothiophenol, 3-aminothiophenol, 4-aminothiophenol, 3-ethynylaniline, 4-ethynylaniline, 3,4-diethynylaniline, 3,5-diethynylaniline and the like are preferable.

  Acid anhydrides, monocarboxylic acids, monoacid chloride compounds, and active ester compounds used as end-capping agents are phthalic anhydride, maleic anhydride, nadic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride Acid anhydrides such as 2-carboxyphenol, 3-carboxyphenol, 4-carboxyphenol, 2-carboxythiophenol, 3-carboxythiophenol, 4-carboxythiophenol, 1-hydroxy-8-carboxynaphthalene, 1- Hydroxy-7-carboxynaphthalene, 1-hydroxy-6-carboxynaphthalene, 1-hydroxy-5-carboxynaphthalene, 1-hydroxy-4-carboxynaphthalene, 1-hydroxy-3-carboxynaphthalene, 1-hydroxy-2-carboxyl Naphthalene, 1-mercapto-8-carboxynaphthalene, 1-mercapto-7-carboxynaphthalene, 1-mercapto-6-carboxynaphthalene, 1-mercapto-5-carboxynaphthalene, 1-mercapto-4-carboxynaphthalene, 1-mercapto -3-carboxynaphthalene, 1-mercapto-2-carboxynaphthalene, 2-carboxybenzenesulfonic acid, 3-carboxybenzenesulfonic acid, 4-carboxybenzenesulfonic acid, 2-ethynylbenzoic acid, 3-ethynylbenzoic acid, 4- Ethynylbenzoic acid, 2,4-diethynylbenzoic acid, 2,5-diethynylbenzoic acid, 2,6-diethynylbenzoic acid, 3,4-diethynylbenzoic acid, 3,5-diethynylbenzoic acid, 2-ethynyl-1- Naphthoic acid, 3-ethynyl-1-na Toeic acid, 4-ethynyl-1-naphthoic acid, 5-ethynyl-1-naphthoic acid, 6-ethynyl-1-naphthoic acid, 7-ethynyl-1-naphthoic acid, 8-ethynyl-1-naphthoic acid, 2- Ethynyl-2-naphthoic acid, 3-ethynyl-2-naphthoic acid, 4-ethynyl-2-naphthoic acid, 5-ethynyl-2-naphthoic acid, 6-ethynyl-2-naphthoic acid, 7-ethynyl-2-naphthoic acid Acids, monocarboxylic acids such as 8-ethynyl-2-naphthoic acid, and monoacid chloride compounds in which these carboxyl groups are acid chloride, and terephthalic acid, phthalic acid, maleic acid, cyclohexanedicarboxylic acid, 3-hydroxyphthalic acid, 5-norbornene-2,3-dicarboxylic acid, 1,2-dicarboxynaphthalene, 1,3-dicarboxynaphthalene, 1,4-dicarboxyl Sinaphthalene, 1,5-dicarboxynaphthalene, 1,6-dicarboxynaphthalene, 1,7-dicarboxynaphthalene, 1,8-dicarboxynaphthalene, 2,3-dicarboxynaphthalene, 2,6-dicarboxynaphthalene , Monoacid chloride compounds in which only the monocarboxyl group of dicarboxylic acids such as 2,7-dicarboxynaphthalene is acid chloride, monoacid chloride compounds and N-hydroxybenzotriazole or N-hydroxy-5-norbornene-2,3- Examples include active ester compounds obtained by reaction with dicarboximide.

  Of these, phthalic anhydride, maleic anhydride, nadic anhydride, cyclohexanedicarboxylic anhydride, acid anhydrides such as 3-hydroxyphthalic anhydride, 3-carboxyphenol, 4-carboxyphenol, 3-carboxythiophenol 4-carboxythiophenol, 1-hydroxy-7-carboxynaphthalene, 1-hydroxy-6-carboxynaphthalene, 1-hydroxy-5-carboxynaphthalene, 1-mercapto-7-carboxynaphthalene, 1-mercapto-6-carboxy Naphthalene, 1-mercapto-5-carboxynaphthalene, 3-carboxybenzenesulfonic acid, 4-carboxybenzenesulfonic acid, 3-ethynylbenzoic acid, 4-ethynylbenzoic acid, 3,4-diethynylbenzoic acid, 3,5-diethynyl benzoic acid Monocarboxylic acids, and monoacid chloride compounds in which these carboxyl groups are converted to an acid chloride, terephthalic acid, phthalic acid, maleic acid, cyclohexanedicarboxylic acid, 1,5-dicarboxynaphthalene, 1,6-dicarboxynaphthalene, 1 , 7-dicarboxynaphthalene, 2,6-dicarboxynaphthalene and the like monocarboxylic acid compounds in which only the monocarboxyl group of the dicarboxylic acid is converted to acid chloride, monoacid chloride compound and N-hydroxybenzotriazole or N-hydroxy-5- Active ester compounds obtained by reaction with norbornene-2,3-dicarboximide are preferred.

  The introduction ratio of the monoamine used for the end-capping agent is preferably in the range of 0.1 to 60 mol%, particularly preferably 5 to 50 mol%, based on the total amine component. The introduction ratio of the compound selected from the acid anhydride, monocarboxylic acid, monoacid chloride compound and monoactive ester compound used as the end-capping agent is in the range of 0.1 to 100 mol% with respect to the diamine component. Preferably, it is 5-90 mol% especially preferably. A plurality of different terminal groups may be introduced by reacting a plurality of terminal blocking agents.

The end-capping agent introduced into the polymer can be easily detected by the following method. For example, a polymer having an end-capping agent introduced therein is dissolved in an acidic solution and decomposed into an amine component and an acid anhydride component that are constituent units of the polymer. By measuring this with gas chromatography (GC) or NMR, the end-capping agent can be easily detected. In addition, it can be easily detected by directly measuring the polymer component into which the end-capping agent has been introduced by pyrolysis gas chromatography (PGC), infrared spectrum and ¹³ CNMR spectrum.

General formula (2)
(In the general formula, X and Y each contain a monocyclic or condensed polycyclic aliphatic group or a monocyclic or condensed polycyclic aromatic group, and have 4 carbon atoms. Represents a linking group of ˜30.X and Y may be composed of one ring structure or may have a plurality of ring structures.)
At least one of X and Y in the general formula (2) is preferably a monocyclic or condensed polycyclic aliphatic group, X is an aromatic group, and Y is monocyclic or condensed polycyclic. The polymer which is an aliphatic group is more preferable.
X is more preferably an aromatic ring, a cyclohexane ring or a bicyclo ring, which may have a substituent. Y is more preferably exemplified by an aromatic ring, a cyclohexane ring and a bicyclo ring, which may have a substituent. Examples of the substituent include a halogen atom, an alkyl group, and an alkoxy group.
By using the polymer having the repeating unit represented by the general formula (2), the adhesion with the near-infrared reflective film can be improved.

  Examples of the polyimide resin film used in the present invention include those described in JP-A-2006-213827, JP-A-2006-117910, and the like.

It is preferable that the polyimide resin used for this invention has as a main component the repeating unit represented by General formula (1) and / or the repeating unit represented by General formula (2). The main component referred to here means that 70 mol% or more of the repeating unit represented by the general formula (1) and / or the repeating unit represented by the general formula (2) is contained. More preferably, it is 80 mol% or more, and most preferably 90 mol% or more.
The resin used in the present invention may be a copolymer of the repeating unit represented by the general formula (1) and / or the repeating unit represented by the general formula (2) and another repeating unit, or Further, it may be a mixture of a plurality of resins containing the repeating unit represented by the general formula (1) and / or the repeating unit represented by the general formula (2).
Further, the resin containing the repeating unit represented by the general formula (1) and / or the repeating unit represented by the general formula (2) and the repeating unit represented by the general formula (1) and / or the general formula (1) It may be a mixture with a resin not containing the repeating unit represented by 2). In this case, the resin containing the repeating unit represented by the general formula (1) and / or the repeating unit represented by the general formula (2) preferably contains 50% by mass or more, and contains 75% by mass or more. It is more preferable.
The type and amount of the repeating unit used for copolymerization or mixing is preferably selected within a range that does not impair the heat resistance of the polymer obtained by the final heat treatment.

The polyimide resin used in the present invention has a mass average molecular weight of preferably 200,000 or less, more preferably 1,000 to 200,000, and more preferably 2,000 to 100,000 from the viewpoint of film properties and the like. 3,000 to 100,000 is particularly preferable. By setting this molecular weight range, a film having low mechanical stress and excellent mechanical properties can be obtained. In the present invention, the molecular weight is measured by gel permeation chromatography and can be determined using a standard polystyrene calibration curve.
The dispersity (molecular weight distribution) is preferably 1.0 to 4.0, and more preferably 1.0 to 3.5.

The glass transition temperature (Tg) of the polyimide resin is preferably 250 ° C. or higher, and more preferably 300 ° C. or higher. The upper limit is not particularly defined, but is, for example, 450 ° C. or lower.
As a method of forming the polyamide resin on the film, a known method can be adopted, and for example, the description of paragraph numbers 0058 to 0070 of JP-A-2006-213827 can be referred to.

It is preferable that the polyimide resin film in this invention contains a near-infrared absorber. Examples of near-infrared absorbers include squarylium dyes, cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, quaterrylene dyes, dithiol metal complex dyes, transition metal oxide compounds, and “e-ex color IR- 10 "," EEX COLOR IR-12 "," EEX COLOR IR-14 "," EEX COLOR HA-1 "," EEX COLOR HA-14 "(all trade names, manufactured by Nippon Shokubai Co., Ltd.), “SIR-128”, “SIR-130”, “SIR-132”, “SIR-152”, “SIR-159”, “SIR-162” (all trade names, manufactured by Mitsui Chemicals), “Kayasorb IRG” -022 "," Kayasorb IRG-023 "," Kayasorb IRG-040 "(all trade names, Nippon Kayaku Co., Ltd.) ), “CIR-1081” (trade name, manufactured by Nippon Carlit), “NIR-IM1”, “NIR-AM1” (all trade names, manufactured by Nagase ChemteX), cesium tungsten oxide compound (Sumitomo Metal Mining Co., Ltd.) , Lumogen IR765, Lumogen IR788 (BASF), ARS670T, IRA800, IRA850, IRA868 (Exciton) are preferred.
A film containing a near-infrared absorber can be obtained by coating / molding a liquid obtained by blending a near-infrared absorber in a polyimide resin solution.
Spectral characteristics can be remarkably improved by adding a near-infrared absorber. It is preferable that the addition amount of a near-infrared absorber is contained in the polyimide resin film in a proportion of 0.1 to 50% by weight, and more preferably in a proportion of 0.5 to 30% by weight.

  In addition to the above, various additives can be added to the polyimide resin film in the present invention. Specific examples include surfactants, antioxidants, and heat stabilizers.

<Near-infrared reflective film>
The near-infrared cut filter of the present invention has a near-infrared reflective film composed of a dielectric multilayer film. The dielectric multilayer film preferably has a structure in which low refractive index layers and high refractive index layers are alternately stacked. By having such a dielectric multilayer film on at least one surface of the polyimide resin film, a near-infrared cut filter excellent in ability to reflect near-infrared light can be obtained. Further, the difference in refractive index between the high refractive index layer and the low refractive index layer is preferably 0.5 or more, and more preferably 1.0 or more. When the difference in refractive index is 1.0 or more, the wavelength range of the near infrared region that can be cut is widened, and a filter having better near infrared ray cutting performance can be obtained.

<High refractive index layer>
As a refractive index of the material which comprises a high refractive index layer, it is 1.6 or less normally, and 1.2-1.6 are preferable. Examples of such a material include silica (SiO ₂ ), alumina, lanthanum fluoride, magnesium fluoride, sodium hexafluoroaluminum, and the like, and silica is preferable.

<Low refractive index layer>
As a refractive index of the material which comprises a low-refractive-index layer, it is 1.7 or more normally, and 1.7-2.5 are preferable. Examples of such materials include titanium oxide (titania (TiO ₂ )), zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, indium oxide, and the like as main components. Examples thereof include titanium oxide (titania (TiO ₂ )), tin oxide, cerium oxide and the like in a small amount. Preferred are titania (TiO ₂ ), ITO (tin-doped indium oxide) and ATO (antimony-doped tin oxide). In particular, when ITO (tin-doped indium oxide) and ATO (antimony-doped tin oxide) are used, the electromagnetic wave region can be cut, which is more effective.

<Lamination method>
The method of laminating the high-refractive index layer and the low-refractive index layer is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, by CVD, sputtering, vapor deposition, etc. A dielectric multilayer film can be formed by alternately laminating high refractive index layers and low refractive index layers. Especially in this invention, since it can manufacture by a vapor deposition method, there exists a merit that productivity improves. It is preferable that the substrate temperature at the time of vapor deposition is 120-300 degreeC.

  The thicknesses of the high-refractive index layer and the low-refractive index layer are usually 0.1λ to 0.5λ of the near infrared wavelength λ (nm) to be blocked. If the thickness is out of the above range, the product (n × d) of the refractive index (n) and the film thickness (d) is greatly different from the optical film thickness calculated by λ / 4. There is a tendency that the relationship between the optical characteristics is broken, and control for blocking / transmitting a specific wavelength cannot be performed.

  The number of laminated layers of the high refractive index layer and the low refractive index layer is usually 10 to 80 layers, preferably 10 to 30 layers when the dielectric multilayer film is provided only on one surface of the polyimide resin film. On the other hand, when the dielectric multilayer film is provided on both sides of the polyimide resin film, the number of laminated layers is generally 10 to 80 layers, preferably 10 to 30 layers as the whole number of laminated layers on both sides of the substrate.

The near-infrared cut filter according to the present invention has an excellent near-infrared cut ability, has excellent heat resistance, and is less likely to cause distortion or cracking. Therefore, it is useful not only as a heat ray cut filter mounted on glass of automobiles and buildings, but also particularly useful for correcting the visibility of solid-state image sensors such as CCDs and CMOSs in digital still cameras and mobile phone cameras. Therefore, it can be suitably used for applications that require high-temperature adhesion during product incorporation, use in a high-temperature region, and the like.
Moreover, it can use preferably also for an organic EL element, a solar cell element, etc.

  The present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

Example 1
(1) Synthesis of polyamic acid (polyimide precursor, dope A) In a 200 mL flask equipped with a thermometer, a stirrer, and a nitrogen introduction tube, 2,2′-dimethyl-4,4′-diaminobiphenyl (Wakayama Seiki ( Co., Ltd.) 10.615 g was added and dissolved in 120.64 g of N-methyl-2-pyrrolidone, and then (1R, 2S, 4S, 5R) -cyclohexanetetracarboxylic dianhydride (Iwatani) at 2 ° C. under ice cooling. 10.675 g (manufactured by Gas Co., Ltd.) was added. When the reaction was carried out at 4 ° C. for 1 hour and then at 25 ° C. for 24 hours, a transparent polyamic acid solution was obtained. When the obtained solution was analyzed by GPC, it was Mw = 3.71 × 10 ⁻⁴ and Mn = 2.02 × 10 ⁻⁴ (dope A).
GPC measurement was performed by directly connecting three HPC-8220GPC (manufactured by Tosoh Corporation), guard column: TSKguardcolumn SuperAW-H, column: TSKgel SuperAWM-H, column temperature of 50 ° C., and sample concentration of 0.5 mass%. 20 μl of 2-pyrrolidone solution was injected, and N-methyl-2-pyrrolidone solution (containing LiBr (10 mM) and H ₃ PO ₄ (10 mM)) as an elution solvent was allowed to flow at a flow rate of 0.35 ml per minute to detect RI. This was done by detecting the sample peak with the apparatus. Mw and Mn were calculated using a calibration curve prepared using standard polystyrene.

(2) Creation of film Next, dope A was cast on a glass plate with a doctor blade, and dried at 80 ° C. Before the dope was completely dried, the dope was peeled off from the glass plate, cut into a size of 120 mm × 120 mm, and stretched by a simultaneous biaxial stretching machine. The stretching conditions were a resin temperature of 120 ° C., a stretching speed of 200 mm / min (both longitudinal and lateral), a distance between chucks of 100 mm, and a stretching ratio of 1.7 times (area ratio). The produced stretched film was framed and vacuum-dried at 200 ° C. for 2 h, and then the frame was removed and heated at 300 ° C. for 2 h. The obtained base film had a good appearance with no foreign matter, unevenness or repellency observed by visual observation. The thickness of the resin film was 79 μm.

(3) Deposition The SiO ₂ layer and the TiO ₂ layer are alternately deposited on the obtained base film at a substrate temperature of 280 ° C. by the electron beam evaporation (EB) method, and both sides of the dielectric multilayer film are formed. To obtain a laminated film with a dielectric multilayer film. The dielectric multilayer film layer formed on the base film had a layer configuration of one layer of 70 to 180 nm and 18 layers on one side (the outermost layer was a SiO ₂ layer).

(4) Evaluation <Appearance evaluation>
The obtained near-infrared cut filter was visually confirmed to be free from cracks, peeling, or unevenness, and those having no failure were indicated as “◯”, and those having any failure were indicated as “X”.

<Spectral characteristic evaluation>
The spectral characteristics of the IR cut filter were evaluated using a spectrophotometer (U-4100 type, manufactured by Hitachi High-Technologies Corporation). The incident angle is changed perpendicularly to the film surface (angle 0 degree) and 35 degrees, and the wavelength at which the transmittance is 50% on the high wavelength side in the transmission band (visible light region) (near 650 nm, hereinafter “high wavelength end wavelength”) And a wavelength at which the transmittance is 50% on the low wavelength side (around 400 nm, hereinafter referred to as “low wavelength end wavelength”). Next, the shift amount of the “high wavelength end wavelength” and the “low wavelength end wavelength” depending on the incident angle was obtained by the following equation.

  In recent years, the requirements for TH and TL have become stricter, and it can be said that when the TH value or TL value decreases by 2 nm, it is a significant decrease.

<Heat resistance>
The IR cut filter was cut into 2 cm × 2 cm and heated on a hot plate at 260 ° C. for 3 minutes. Before and after heating, using a spectrophotometer (U-4100, manufactured by Hitachi High-Technologies Corporation), the spectrum in the wavelength region of 300 to 1300 nm was measured at an incident angle of 0 degree, and the area of spectral transmittance before and after heating. The change amount of the integrated value of less than 5% is “◯”, 5% or more and less than 10% is “Δ”, and 10% or more is “x”.

In Example 1, the dope and the film thickness were changed as shown in the following table, and others were carried out in the same manner to produce near-infrared cut filters of various Examples and Comparative Examples.
For Example 6, a dielectric multilayer film was formed in the same manner as in Example 1 except that the TiO ₂ layer was changed to an ITO layer in the vapor deposition step. Further, Comparative Example 1 was carried out in the same manner as in Example 1, except that the polyamide resin film was changed to TAC (Fujitack 80UL, manufactured by Fuji Film).

<Creation of dope B>
In a 5000 mL flask equipped with a thermometer, a stirrer, and a nitrogen introducing tube, 123.42 g of trans-1,4-cyclohexanediamine (manufactured by Iwatani Gas Co., Ltd.) was placed and NMP (N-methyl-2-pyrrolidone) 2399 After dissolution in 4 g, 300.00 g of 3,3 ′, 4,4′-biphenyltetracarboxylic anhydride (manufactured by Mitsubishi Chemical Corporation) was added. The mixture was stirred at 60 ° C. for 4 hours and then allowed to cool to room temperature. Next, 30.27 g of phthalic anhydride was added and stirred at room temperature for 10 hours to obtain a colorless and transparent polyamic acid solution. The resulting solution was analyzed by GPC, Mw = 1.68 × 10 ^- were ^{4, Mw / Mn = 2.71 -} 4, Mn = 0.62 × 10.

<Creation of dope C>
In the dope A, Lumogen IR788 (manufactured by BASF) was added at a ratio of 0.3 part by weight with respect to 100 parts by weight of the polyamic acid.

<Creation of dope E>
A norbornene-based resin “ZEONOR 1400R” manufactured by Nippon Zeon Co., Ltd. was dissolved by adding a 7: 3 mixed solution of cyclohexane and xylene to obtain a solution having a solid content of 20% (Dope E). The solution was cast on a smooth glass plate, dried at 60 ° C. for 8 hours, and at 80 ° C. for 8 hours, and then peeled off from the glass plate. The peeled resin was further dried at 100 ° C. under reduced pressure for 24 hours.

  As is apparent from the above results, in the present invention, the spectral characteristics can be remarkably improved by setting the thickness of the polyimide resin film to 80 μm.

Claims (13)

It has a near-infrared reflective film consisting of a polyimide resin film and a dielectric multilayer film,
The polyimide resin film includes a polymer having a repeating unit represented by the following general formula (2),
The polyimide resin film is a near infrared cut filter having a thickness of 10 μm or more and 80 μm or less,
The near-infrared cut filter has a transmittance of 50% in the vicinity of 650 nm on the high wavelength side in the visible light region obtained by changing the incident angle to 0 ° and 35 ° with respect to the film surface of the near-infrared cut filter. TH, which is the shift amount of the high wavelength end wavelength depending on the incident angle, obtained from the following formula of the high wavelength end wavelength which is the wavelength is 3 to 14 nm,
And,
Low wavelength end wavelength, which is a wavelength at which the transmittance is 50% near 400 nm on the low wavelength side in the visible light range obtained by changing the incident angle to 0 ° and 35 ° with respect to the film surface of the near-infrared cut filter The TL, which is the shift amount of the low wavelength end wavelength due to the incident angle, obtained from the following equation is 11 to 15 nm.
Near-infrared cut filter.
TH (nm) = | (high wavelength end wavelength at an incident angle of 0 degree) − (high wavelength end wavelength at an incident angle of 35 degrees) |
TL (nm) = | (low wavelength end wavelength at an incident angle of 0 degree) − (low wavelength end wavelength at an incident angle of 35 degrees) |
(In general formula (2), X represents an aromatic hydrocarbon group having 4 to 30 carbon atoms, and Y represents a monocyclic aliphatic group having 4 to 30 carbon atoms. )   The near-infrared cut filter according to claim 1, wherein the polyimide resin film contains a near-infrared absorber.   The near-infrared absorber is at least one selected from squarylium dyes, cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, quatarylene dyes, dithiol metal complex dyes, and transition metal oxide compounds. The near infrared cut filter according to claim 2.   The near-infrared cut filter according to claim 1, wherein the dielectric multilayer film has a structure in which low refractive index layers and high refractive index layers are alternately stacked.   The near-infrared cut filter according to claim 4, wherein a difference in refractive index between the high refractive index layer and the low refractive index layer is 0.5 or more. 6. The near-infrared cut filter according to claim 4, wherein one of the low refractive index layers includes silica (SiO ₂ ), and one of the high refractive index layers includes titania (TiO ₂ ). Said one of the low refractive index layer comprises a silica (SiO _2), wherein the high refractive index layer comprises any one of ITO (tin-doped indium oxide) or ATO (antimony-doped tin oxide), according to claim 4 or 5 Near infrared cut filter.   The near-infrared cut filter according to claim 1, wherein a thickness of the polyimide resin film is 60 μm or less.   The near-infrared cut filter according to claim 1, wherein the polyimide resin film has a glass transition temperature of 250 ° C. or higher.   A near-infrared cut filter was cut out to 2 cm × 2 cm, heated on a hot plate at 260 ° C. for 3 minutes, and the spectrum in the wavelength region of 400-1100 nm before and after heating was measured at an incident angle of 0 degree. The near-infrared cut filter according to claim 1, wherein the amount of change in the integrated value of the area is less than 10%.   The solid-state image sensor using the near-infrared cut filter of any one of Claims 1-10. It is a manufacturing method of the near-infrared cut filter according to any one of claims 1 to 10,
Forming a near-infrared reflective film made of a dielectric multilayer film by vapor deposition on a polyimide resin film having a thickness of 10 μm or more and 80 μm or less, including a polymer having a repeating unit represented by the following general formula (2) A method for producing a near-infrared cut filter, comprising:
(In general formula (2), X represents an aromatic hydrocarbon group having 4 to 30 carbon atoms, and Y represents a monocyclic aliphatic group having 4 to 30 carbon atoms. )   The manufacturing method of the near-infrared cut filter of Claim 12 whose vapor deposition temperature is 120-300 degreeC.