JP2008050567A - Polyimide resin, polyimide resin layer using the same, and optical compensation member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyimide layer exhibiting a small variation of retardation from a long wave length to a short wave length in the visible light region. <P>SOLUTION: The polyimide resin having high transparency and a small variation of retardation from a long wave length to a short wave length in a visible light region is composed of 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) contained therein, an aliphatic acid dianhydride, and an aliphatic diamine for other parts. According to the polyimide resin, the coating resin layer can be provided by dissolving the optical material having excellent characteristcs inherent in a polyimide resin, and the above optical properties. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polyimide resin having excellent optical characteristics, a polyimide resin layer using the same, and an optical compensation member.

  In recent years, a retardation film is generally used in a liquid crystal display device for the purpose of optical compensation. Conventionally, polycarbonate was used for compensation of STN liquid crystal, but as the liquid crystal shifts to TFT mode, it has excellent high transparency and changes in retardation from long wavelength to short wavelength in the visible light region. An optical compensation member having a small amount (hereinafter, such a characteristic is sometimes referred to as a low wavelength dispersion characteristic) has been required. In addition, there are increasing demands for such optical characteristics in other applications.

  In response to such demands, cyclic olefin polymers having excellent low wavelength dispersion characteristics are used. However, this polymer has a problem that the film thickness required for compensation increases because of the small retardation development.

  On the other hand, a stretched polymer film has been used as a conventional retardation film, but as an alternative, for example, a coating layer using a polyimide resin has been proposed (see, for example, Patent Documents 1 and 2). ). By using the film as a coating layer, it is possible to reduce the thickness, and the manufacturing process and the bonding process to the polarizing plate can be omitted, so that the manufacturing cost can be suppressed.

However, when a coating layer is formed using a conventional polyimide resin during optical compensation, the amount of retardation change from a long wavelength to a short wavelength in the visible light region is large, and the above requirement cannot be satisfied. It was. In particular, when black display is performed on a liquid crystal display device using such a polyimide resin layer having a large amount of retardation change, the light from the backlight cannot be completely blocked, resulting in a decrease in contrast and gradation display. There was a fear.
Japanese translation of PCT publication No. 8-511812 Special table 2000-511296

  The present invention has been made in view of the above-mentioned problems of the prior art, and is a polyimide resin that has a small amount of change in retardation from a long wavelength to a short wavelength in the visible light region and that has excellent retardation. The purpose is to provide a layer. It is another object of the present invention to provide a polyimide resin layer having a property that the change amount on the short wavelength side is particularly small.

As a result of intensive studies, the present inventors have completed the present invention. That is, the present invention
(I) A polyimide resin layer satisfying the following formula 1 and the following formula 2.

1.00 ≦ Re (450) / Re (550) ≦ 1.05: Formula 1
(Re (λ) is a layer formed by using a polyimide resin with the horizontal plane as the reference plane, and is inclined with respect to the reference plane by 40 ° about the fast axis of the layer, while the wavelength λnm (In-plane retardation (nm) in a plane inclined by 40 ° with respect to the plane on which the layer is formed, measured by irradiating measurement light from the direction perpendicular to the reference plane.)
0.010 ≦ Δn ≦ 0.060: Formula 2
(Here, birefringence (Δn) is the refractive index in the plane inclined by 40 ° with respect to the plane on which the polyimide layer is formed in the same manner as described above, nx and ny, and the refractive index in the direction perpendicular to this plane is nz. In this case, Δn = [(nx + ny) / 2] −nx.)
(Ii) The polyimide resin layer according to (i), which is formed by containing a unit represented by the following general formula (0).

（Ｑは環を形成する炭素の半分以上が脂肪族炭素である環式を含み、カルボニル炭素が結合しているＱの炭素が脂肪族炭素である。またＰは２価の芳香族基又は脂肪族基である。）
（ＩＩＩ） 下記一般式（１）で表されるユニット、及び／又は、下記一般式（２）で表されるユニットを含有して形成されることを特徴とする、（ｉ）又は（ｉｉ）記載のポリイミド樹脂層。

(Q includes a ring in which more than half of the carbons forming the ring are aliphatic carbons, and the carbon of Q to which the carbonyl carbon is bonded is an aliphatic carbon. P is a divalent aromatic group or aliphatic carbon. A group.)
(III) It is formed by containing a unit represented by the following general formula (1) and / or a unit represented by the following general formula (2), (i) or (ii) The polyimide resin layer described.

（ここでＲ_１は、炭素数が１〜２０である炭化水素からなり、イミド基が結合している炭素が、脂肪族炭素であり、Ｒ_２はイミド基が結合している炭素が芳香族炭素である炭化水素である。）
（ｉｖ） 一般式（２）が、下記一般式（４）であることを特徴とする、（ｉｉｉ）記載のポリイミド樹脂層。

(Here, R ₁ is composed of a hydrocarbon having 1 to 20 carbon atoms, the carbon to which the imide group is bonded is aliphatic carbon, and R ₂ is the carbon to which the imide group is bonded is aromatic. It is a hydrocarbon that is carbon.)
(Iv) The polyimide resin layer according to (iii), wherein the general formula (2) is the following general formula (4).

（ｖ） 一般式（１）で表されるユニットのモル分率をＡ、一般式（２）で表されるユニットのモル分率をＢとして表した時に、
０．１０≦Ａ≦０．５０
且つ、
０．５０≦Ｂ≦０．９０
が成り立つ（但し、０．６≦Ａ＋Ｂ≦１．０）ことを特徴とする（ｉｉｉ）または（ｉｖ）に記載のポリイミド樹脂層。
（ｖｉ） 一般式（１）で表されるユニットにおいて、Ｒ_１が一般式群（５）で表される群から選ばれる１以上の構造であることを特徴とする（ｉｉｉ）〜（ｖ）のいずれかに記載のポリイミド樹脂層。

(V) When the molar fraction of the unit represented by the general formula (1) is represented as A and the molar fraction of the unit represented by the general formula (2) is represented as B,
0.10 ≦ A ≦ 0.50
and,
0.50 ≦ B ≦ 0.90
Is satisfied (provided that 0.6 ≦ A + B ≦ 1.0). The polyimide resin layer according to (iii) or (iv).
(Vi) In the unit represented by the general formula (1), R ₁ is one or more structures selected from the group represented by the general formula group (5) (iii) to (v) The polyimide resin layer according to any one of the above.

（但し、式中のＸは、Ｏ、ＳＯ_２、ＣＨ_２、Ｃ（ＣＨ_３）_２、Ｃ（ＣＦ_３）_２から選ばれる置換基であり、式中のＹはそれぞれ独立して、Ｈ、Ｆ、Ｃｌ、Ｂｒ，ＣＦ_３、ＣＣｌ_３、ＣＢｒ_３から選ばれる置換基である。）
（ｖｉｉ） 一般式（１）で表されるユニットにおいて、Ｒ_１が一般式（６）で表される構造であることを特徴とする（ｉｉｉ）〜（ｖｉ）のいずれかに記載のポリイミド樹脂層。

(Wherein, X is a substituent selected from O, SO ₂ , CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , and Y in the formula is independently H, This is a substituent selected from F, Cl, Br, CF ₃ , CCl ₃ and CBr _3. )
(Vii) The polyimide resin according to any one of (iii) to (vi), wherein in the unit represented by the general formula (1), R ₁ has a structure represented by the general formula (6) layer.

（ｖｉｉｉ） 一般式（１）で表されるユニットのモル分率をＡ、一般式（２）で表されるユニットのモル分率をＢとして表した時に、
０．１５≦Ａ≦０．５０
且つ、
０．５０≦Ｂ≦０．８５
が成り立つ（但し、０．６５≦Ａ＋Ｂ≦１．０）ことを特徴とする（ｖｉｉ）に記載のポリイミド樹脂層。
（ｉｘ） 下記一般式（７）で表されるユニットを含有して形成されることを特徴とする（ｉ）または（ｉｉ）記載のポリイミド樹脂層。

(Viii) When the mole fraction of the unit represented by the general formula (1) is represented as A and the mole fraction of the unit represented by the general formula (2) is represented as B,
0.15 ≦ A ≦ 0.50
and,
0.50 ≦ B ≦ 0.85
Is satisfied (provided that 0.65 ≦ A + B ≦ 1.0). The polyimide resin layer according to (vii).
(Ix) The polyimide resin layer according to (i) or (ii), which is formed by containing a unit represented by the following general formula (7).

（Ｒは、シクロブタンの炭素に結合しており、それぞれ独立した炭素数１〜１２の脂肪族基又は芳香族基である。Ｃは、２価の芳香族基又は脂肪族基を表す。）
（ｘ） さらに、下記一般式（８）で表されるユニットを含有して形成されることを特徴とする（ｉｘ）記載のポリイミド樹脂層。

(R is bonded to the carbon of cyclobutane and is an independent aliphatic group or aromatic group having 1 to 12 carbon atoms. C represents a divalent aromatic group or aliphatic group.)
(X) The polyimide resin layer according to (ix), further comprising a unit represented by the following general formula (8).

（Ｄは、環を形成する炭素の半分以上が脂肪族炭素である環式を含み、カルボニル炭素が結合しているＤの炭素が脂肪族炭素である。ただし、置換または無置換のシクロブタン残基を除く。Ｃは前記に同じ。）
（ｘｉ）
一般式（７）で表されるユニットにおいて、Ｒがメチル基であることを特徴とする、（ｉｘ）または（ｘ）記載のポリイミド樹脂層。

(D includes a cyclic group in which more than half of the carbons forming the ring are aliphatic carbons, and the carbon of D to which the carbonyl carbon is bonded is an aliphatic carbon, provided that a substituted or unsubstituted cyclobutane residue. (C is the same as above.)
(Xi)
The polyimide resin layer according to (ix) or (x), wherein in the unit represented by the general formula (7), R is a methyl group.

  (Xii) It is formed by containing a unit represented by the following general formula (9) and a unit represented by the following general formula group (10), described in (x) or (xi) Polyimide resin layer.

（Ｃは、２価の芳香族基又は脂肪族基を表す。）
（ｘｉｉｉ）
厚さが１μｍ以上、４０μｍ未満であることを特徴とする（ｉ）〜（ｘｉｉ）のいずれかに記載のポリイミド樹脂層。
（ｘｉｖ） （ｉ）〜（ｘｉｉｉ）の何れかに記載のポリイミド樹脂層と、プラスティックフィルム基盤からなることを特徴とする、積層体。
（ｘｖ） （ｘｉｖ）に記載の積層体を、プラスティックフィルム基盤上にポリイミド樹脂層を塗布、乾燥して形成することを特徴とする、積層体の製造方法。
（ｘｖｉ） （ｘｉｖ）に記載の積層体を、プラスティックフィルム基盤上にポリイミド樹脂層を転写して形成することを特徴とする、積層体の製造方法。
（ｘｖｉｉ） （ｉ）〜（ｘｖｉ）のいずれかに記載のポリイミド樹脂層又は積層体を含有して形成されることを特徴とする、光学補償部材。
（ｘｖｉｉｉ） ポリイミド樹脂の固形成分濃度が２５重量％であるジメチルホルムアミド溶液を、ガラス基板上に塗布した後、９０℃で２０分間乾燥後、さらに、２００℃で２０分間乾燥させて形成した膜厚１１．９μｍのコーティング層が、下記数式３且つ、下記数式４を満たすことを特徴とするポリイミド樹脂。

(C represents a divalent aromatic group or an aliphatic group.)
(Xiii)
Thickness is 1 micrometer or more and less than 40 micrometers, The polyimide resin layer in any one of (i)-(xii) characterized by the above-mentioned.
(Xiv) A laminate comprising the polyimide resin layer according to any one of (i) to (xiii) and a plastic film substrate.
(Xv) A method for producing a laminate, wherein the laminate according to (xiv) is formed by applying and drying a polyimide resin layer on a plastic film substrate.
(Xvi) A method for producing a laminate, wherein the laminate according to (xiv) is formed by transferring a polyimide resin layer onto a plastic film substrate.
(Xvii) An optical compensation member comprising the polyimide resin layer or laminate according to any one of (i) to (xvi).
(Xviii) A film thickness formed by applying a dimethylformamide solution having a polyimide resin solid component concentration of 25% by weight on a glass substrate, drying at 90 ° C. for 20 minutes, and further drying at 200 ° C. for 20 minutes. A polyimide resin characterized in that a coating layer of 11.9 μm satisfies the following formula 3 and the following formula 4.

1.00 ≦ Re (450) / Re (550) ≦ 1.05: Formula 3
(Re (λ) is a layer formed by using a polyimide resin with the horizontal plane as the reference plane, and is inclined with respect to the reference plane by 40 ° about the fast axis of the layer, while the wavelength λnm (In-plane retardation (nm) in a plane inclined by 40 ° with respect to the plane on which the layer is formed, measured by irradiating measurement light from the direction perpendicular to the reference plane.)
0.010 ≦ Δn ≦ 0.060: Formula 4
(Here, birefringence (Δn) is the refractive index in the plane inclined by 40 ° with respect to the plane on which the polyimide layer is formed in the same manner as described above, nx and ny, and the refractive index in the direction perpendicular to this plane is nz. In this case, Δn = [(nx + ny) / 2] −nx.)
About.

  The polyimide resin layer of the present invention is an optical layer that has a small amount of change in retardation from a long wavelength to a short wavelength in the visible light region, has excellent phase difference, and satisfies recently required optical characteristics. It becomes possible to provide.

  In particular, when the polyimide resin layer of the present invention is used as an optical compensation member for a liquid crystal display device or the like, leakage of light from the backlight during black display or the like can be reduced (especially color leakage on the short wavelength side). This is useful because it is possible to reduce the decrease in contrast and gradation display.

  Moreover, the polyimide resin layer of the present invention is useful because it has various excellent properties such as heat resistance and dimensional stability derived from the polyimide resin.

  The present invention relates to a polyimide resin characterized by satisfying the following mathematical formula 1.

1.00 ≦ Re (450) / Re (550) ≦ 1.05: Formula 1
The upper limit of the above mathematical formula is more preferably 1.04 or less, and particularly preferably 1.03 or less. By satisfying Equation 1, the resin layer exhibits a property that changes in retardation from a long wavelength to a short wavelength in the visible light region is small, and compared with a layer formed using a conventional polyimide resin, When used as an optical compensation member for a display device or the like, leakage of light from the backlight during black display or the like can be reduced, and reduction in contrast and gradation display can be reduced.

  In addition, the retardation value (Re (λ)) used in Equation 1 is a layer formed using a polyimide resin when the horizontal plane is the reference plane as shown in FIG. Measured by irradiating measurement light with a wavelength of λ nm from the direction perpendicular to the reference plane, measured in a plane inclined by 40 ° with respect to the plane on which the layer is formed. Retardation (nm) ". However, since the layer formed using polyimide resin is an unstretched layer, the measured value is the same when tilted about the slow axis of the layer and tilted about the fast axis. It was. This value is an effective index for evaluating the performance of reducing leakage of light from the backlight when a polyimide resin is used as an optical compensation layer of a liquid crystal display device or the like and black display is performed. For actual measurement, Kobra-WR (Oji measurement) was used.

  Here, the value represented as “Re (450) / Re (550)” can be used as an index indicating the wavelength dependence of retardation in the resin. In this invention, it can adjust to a desired value by selecting the composition of resin suitably.

  Moreover, the polyimide resin of this invention is related with the polyimide resin characterized by satisfy | filling Numerical formula 2 simultaneously with satisfy | filling Numerical formula 1 above.

0.010 ≦ Δn ≦ 0.060: Formula 2
Here, birefringence (Δn) is the refractive index in the plane inclined by 40 ° with respect to the plane on which the polyimide resin layer is formed in the same manner as described above, nx and ny, and the refractive index in the direction perpendicular to this plane When nz, it is a value represented by the following formula. Actually, the phase difference value was obtained with the Kobra-WR in a state where it was tilted by 40 ° and in a state where it was not tilted, and this was used to calculate the phase difference value using Kobra-RE (prince measurement).

Δn = [(nx + ny) / 2] −nz
In the present invention, Δn can be adjusted to a desired value by appropriately selecting the composition of the resin.

  When providing the polyimide resin which has the said characteristic, it is preferable that this invention contains the structure represented by General formula (0).

（Ｑは環を形成する炭素の半分以上が脂肪族炭素である環式を含み、カルボニル炭素が結合しているＱの炭素が脂肪族炭素である。またＰは２価の芳香族基又は脂肪族基である。）
Ｑは環を形成する炭素の半分以上が脂肪族炭素である環式を含み、カルボニル炭素が結合しているＱの炭素が脂肪族炭素であり、Ｐは２価の芳香族基又は脂肪族基であることで、ポリイミド樹脂層のＲｅ（４５０）／Ｒｅ（５５０）を１．００に近づけることができ、且つポリイミド樹脂層の複屈折（△ｎ）を０．０１０≦△ｎ≦０．０６０の範囲にすることが可能となる。

(Q includes a ring in which more than half of the carbons forming the ring are aliphatic carbons, and the carbon of Q to which the carbonyl carbon is bonded is an aliphatic carbon. P is a divalent aromatic group or aliphatic carbon. A group.)
Q includes a ring in which more than half of the carbons forming the ring are aliphatic carbons, the carbon of Q to which the carbonyl carbon is bonded is an aliphatic carbon, and P is a divalent aromatic group or aliphatic group Therefore, Re (450) / Re (550) of the polyimide resin layer can be brought close to 1.00, and the birefringence (Δn) of the polyimide resin layer is 0.010 ≦ Δn ≦ 0.060. It becomes possible to be in the range.

  The ring contained in Q forms a ring with carbon atoms, and preferably contains at least one monocycle. However, the ring may contain a double bond, but more than half of the carbon atoms forming the ring must be aliphatic carbon (a carbon atom in which all the bonds with adjacent atoms are single bonds). preferable. The cyclic group included in Q is not particularly limited as long as it forms a ring. For example, cyclobutane ring, cyclobutene ring, cyclopentane ring, cyclopentene ring, cyclohexane ring, cyclohexene ring, cycloheptane ring , Cycloheptene ring, cyclooctane ring, cyclooctene ring and the like. The cyclic ring may contain a double bond, but the double bond may be a single bond or may be incorporated as a part of an adjacent aromatic ring.

  The carbon contained in Q to which the carbonyl carbon is bonded is preferably an aliphatic carbon, but the carbon to which the carbonyl carbon is bonded is not limited to the cyclic carbon contained in Q. No.

  P is preferably a divalent aromatic group or an aliphatic group. An aromatic group indicates that carbon having a divalent bond is carbon contained in an aromatic group, and an aliphatic group indicates that carbon having a divalent bond is carbon contained in an aliphatic group.

  As a method of forming the above general formula (0), a tetracarboxylic acid dicarboxylic acid containing a cyclic group in which more than half of the carbons forming the ring are aliphatic carbons and the carbon to which the carbonyl carbon is bonded is an aliphatic carbon. A method of reacting an anhydride with a diamine having a divalent aromatic group or aliphatic group (referred to as an aromatic diamine or an aliphatic diamine) (more specifically, after synthesizing a polyamic acid and then dehydrating and closing it) And a polyimide resin) is generally used.

  A tetracarboxylic dianhydride in which more than half of the carbons forming the ring includes a cyclic group that is an aliphatic carbon and the carbon to which the carbonyl carbon is bonded is an aliphatic carbon includes 3,4-dicarboxytetralin- 1-succinic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 3,3 ′, 4,4 '-Bicyclohexyltetracarboxylic dianhydride, bicyclo [2,2,2] -octane-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2,2,1] -heptane-2, 3,5,6-tetracarboxylic dianhydride, bicyclo [2,2,2] -oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 2,3,4,5 -Tetrahydrofuran tetracarboxylic dianhydride, 3,4-dicarboxy Examples include -1-succinic dianhydride. Further, as tetracarboxylic dianhydrides having a cyclobutane ring or a cyclopentyl ring, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1-methyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride Anhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1-ethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetraethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetraphenylcyclobutanetetracarboxylic dianhydride, 1,3-diaryl- 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-diaryl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3 4- cyclopentane tetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride may also be mentioned. Among the cyclobutane rings, tetracarboxylic dianhydrides containing a disubstituted cyclobutane ring include 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,4-dimethyl. -1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-diethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,4-diethyl-1,2,3 , 4-Cyclobutanetetracarboxylic dianhydride, 1,3-dipropyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,4-dipropyl-1,2,3,4-cyclobutanetetracarboxylic Acid dianhydride, 1,3-dibutyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,4-dibutyl-1,2,3,4-cyclobutanetetracarboxylic acid Water, 1,3-dipentyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,4-dipentyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3 -Dihexyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,4-dihexyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-diphenyl-1,2 , 3,4-cyclobutanetetracarboxylic dianhydride, 1,4-diphenyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dicyclopentyl-1,2,3,4 Examples thereof include cyclobutanetetracarboxylic dianhydride and 1,4-dicyclopentyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride.

    Examples of the aromatic diamine include 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl, 2,2′-bis ( Trichloromethyl) -4,4'-diaminobiphenyl, 2,2'-bis (tribromomethyl) -4,4'-diaminobiphenyl, 2,2'-difluoro-4,4'-diaminobiphenyl, 2,2 '-Dichloro-4,4'-diaminobiphenyl, 2,2'-dibromo-4,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 4,4'-diamino-benzophenone, 9,9-bis ( 4-aminophenyl) fluorene, 9,9-bis (4-amino-2-fluorophenyl) fluorene, 9,9-bis (4-amino-2-bromophenyl) fluorene, 9,9-bis 4-amino-2-chlorophenyl) fluorene, 9,9-bis (4-amino-3-fluorophenyl) fluorene, 9,9-bis (4-amino-3-bromophenyl) fluorene, 9,9-bis ( 4-amino-3-chlorophenyl) fluorene, 9,9-bis (4-amino-2-trifluoromethylphenyl) fluorene, 9,9-bis (4-amino-3-trifluoromethylphenyl) fluorene, bis ( 4-aminophenyl) sulfone, 1,4-diaminobenzene, 1,3-diaminobenzene, 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 2,2- Bis (4-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 3,4'-diaminodiphenyl And ruether.

    Examples of the aliphatic diamine include ethylenediamine, hexamethylenediamine, 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4′-diaminodicyclohexylmethane, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 4,4'-diaminodicyclohexylpropane, bis (4-aminocyclohexyl) sulfone, 4,4'-diaminodicyclohexyl ether, 2,2'-dimethyl-4,4 '-Diaminodicyclohexane, 2,2'-bis (trifluoromethyl) -4,4'-diaminodicyclohexane, 2,2'-bis (trichloromethyl) -4,4'-diaminodicyclohexane, 2,2 '-Bis (tribromomethyl) -4,4'-diaminodicyclohexane, 2, 2'-difluoro-4,4'-diaminodicyclohexane, 2,2'-dichloro-4,4'-diaminodicyclohexane, 2,2'-dibromo-4,4'-diaminodicyclohexane, 4,4 ' -Diaminodicyclohexane, 2,2-bis (4-aminocyclohexyl) -1,1,1,3,3,3-hexafluoropropane, 2,3-diaminobicyclo [2.2.1] heptane, 2,5-diaminobicyclo [2.2.1] heptane, 2,6-diaminobicyclo [2.2.1] heptane, 2,7-diaminobicyclo [2.2.1] heptane, 2,5-bis (Aminomethyl) -bicyclo [2.2.1] heptane, 2,6-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2,3-bis (aminomethyl) -bicyclo [2.2 .1] Heptane, 1 2- bis (aminomethyl) benzene, 1,3-bis (aminomethyl) benzene, 1,4-bis (aminomethyl) benzene.

  In providing a polyimide resin having such characteristics, for example, the structure represented by the general formula (0) can be a structure represented by the general formula (1). By incorporating the structure of the general formula (1) into the polyimide resin, unlike a conventional polyimide resin, a polyimide resin having a property of small change in retardation from a long wavelength to a short wavelength in the visible light region is obtained. It becomes possible.

（ここでＲ_１は、炭素数が１〜２０である炭化水素からなり、イミド基が結合している炭素が、脂肪族炭素である。）
また、上記一般式（１）を形成する方法としては、ジアミンと３，４−ジカルボキシテトラリン−１−コハク酸二無水物とを反応させる方法（より具体的には、一度ポリアミド酸を合成した後、これを脱水閉環してポリイミド樹脂とする方法）が一般的である。また、テトラカルボン酸二無水物として、カルボニル基が結合している炭素が、脂肪族炭素であるものを併用してもよい（以下、この様な酸二無水物を脂肪族テトラカルボン酸二無水物ということがある。）。ここで脂肪族炭素とは、隣接する原子との結合が全て一重結合である炭素原子のことである（即ち、ここでは脂肪族系の炭素のみならず、脂環式の炭素も含むものとする。）。本発明においては、脂肪族テトラカルボン酸二無水物を使用することにより、ポリイミド樹脂の分子内共役及び電荷移動吸収が抑制され、結果として透明性を高め、また、波長変化によるレターデーションの変化量が大きいポリイミド樹脂となることを抑制しているものと推定される。

(Here, R ₁ is a hydrocarbon having 1 to 20 carbon atoms, and the carbon to which the imide group is bonded is an aliphatic carbon.)
Moreover, as a method of forming the general formula (1), a method of reacting a diamine with 3,4-dicarboxytetralin-1-succinic dianhydride (more specifically, a polyamic acid was synthesized once. Thereafter, a method of dehydrating and ring-closing this to obtain a polyimide resin is common. In addition, as the tetracarboxylic dianhydride, carbons to which the carbonyl group is bonded may be an aliphatic carbon (hereinafter, such an acid dianhydride is referred to as an aliphatic tetracarboxylic dianhydride). Sometimes called a thing.) Here, the aliphatic carbon is a carbon atom in which all the bonds to adjacent atoms are single bonds (that is, here, not only aliphatic carbon but also alicyclic carbon is included). . In the present invention, by using an aliphatic tetracarboxylic dianhydride, intramolecular conjugation and charge transfer absorption of the polyimide resin are suppressed, and as a result, transparency is improved, and the amount of change in retardation due to wavelength change It is estimated that it is suppressing that it becomes a polyimide resin with large.

  Specific examples of tetracarboxylic dianhydride having aliphatic carbon and suitably used with 3,4-dicarboxytetralin-1-succinic dianhydride include 1,2,4,5-cyclohexane. Tetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1-methyl-1,2,3,4 -Cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4- Cyclobutanetetracarboxylic dianhydride, 1-ethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-diethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4 Traethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetraphenyl Cyclobutanetetracarboxylic dianhydride, 1,3-diaryl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-diaryl-1,2,3,4-cyclobutanetetra Carboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, bicyclo [2,2,2] -octane-2, 3,5,6-tetracarboxylic dianhydride, bicyclo [2,2,1] -heptane-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2,2,2] -oct- 7-ene-2, , 5,6-tetracarboxylic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, 3,4-dicarboxy-1-succinic acid dianhydride, and the like. It is also possible to use a plurality of these acid dianhydrides in combination for adjusting other characteristics.

  In particular, in the polyimide resin layer of the present case, it is preferable to use 3,4-dicarboxytetralin-1-succinic dianhydride as the tetracarboxylic dianhydride from the viewpoint of imparting solubility to the polyimide resin ( It is also possible to introduce a substituent into the acid dianhydride as long as the essence of the present invention is not impaired.

  On the other hand, in the present invention, the diamine used for forming the unit of the general formula (1) is a diamine to which an amino group is bonded is an aliphatic carbon (hereinafter, such a diamine is referred to as an aliphatic diamine). Can be suitably used. Here, the aliphatic carbon is a carbon atom in which all the bonds to adjacent atoms are single bonds (that is, here, not only aliphatic carbon but also alicyclic carbon is included). . In particular, in the present invention, by using an aliphatic diamine, the intramolecular conjugation and charge transfer absorption of the polyimide resin are suppressed, resulting in an increase in transparency and a large amount of retardation change due to wavelength change. It is estimated that it is possible to suppress this. Examples of such aliphatic diamines that can be suitably used to form the unit of the general formula (1) include, for example, the formation of the structure represented by the general formula (0) described above. The thing similar to the aliphatic diamine to be used is mention | raise | lifted. For example, ethylenediamine, hexamethylenediamine, 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4′-diaminodicyclohexylmethane, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (Aminomethyl) cyclohexane, 4,4'-diaminodicyclohexylpropane, bis (4-aminocyclohexyl) sulfone, 4,4'-diaminodicyclohexyl ether, 2,2'-dimethyl-4,4'-diaminodicyclohexane 2,2'-bis (trifluoromethyl) -4,4'-diaminodicyclohexane, 2,2'-bis (trichloromethyl) -4,4'-diaminodicyclohexane, 2,2'-bis (tri Bromomethyl) -4,4'-diaminodicyclohexane, 2,2'-difluoro- , 4'-diaminodicyclohexane, 2,2'-dichloro-4,4'-diaminodicyclohexane, 2,2'-dibromo-4,4'-diaminodicyclohexane, 4,4'-diaminodicyclohexane, 2, , 2-bis (4-aminocyclohexyl) -1,1,1,3,3,3-hexafluoropropane, 2,3-diaminobicyclo [2.2.1] heptane, 2,5-diaminobicyclo [2.2.1] heptane, 2,6-diaminobicyclo [2.2.1] heptane, 2,7-diaminobicyclo [2.2.1] heptane, 2,5-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2,6-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2,3-bis (aminomethyl) -bicyclo [2.2.1] heptane, , 2-bis (amino Chill) benzene, 1,3-bis (aminomethyl) benzene, 1,4-bis (aminomethyl) benzene. A plurality of these diamines can be used in combination for adjusting other characteristics.

  Among these, 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4'-diaminodicyclohexylmethane, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclo Hexane, 4,4'-diaminodicyclohexylpropane, bis (4-aminocyclohexyl) sulfone, 4,4'-diaminodicyclohexyl ether, 2,2'-dimethyl-4,4'-diaminodicyclohexane, 2,2 ' -Bis (trifluoromethyl) -4,4'-diaminodicyclohexane, 2,2'-bis (trichloromethyl) -4,4'-diaminodicyclohexane, 2,2'-bis (tribromomethyl) -4 , 4'-diaminodicyclohexane, 2,2'-difluoro-4,4'-diaminodicyclohexane, 2,2 ' -Dichloro-4,4'-diaminodicyclohexane, 2,2'-dibromo-4,4'-diaminodicyclohexane, 4,4'-diaminodicyclohexane, 2,2-bis (4-aminocyclohexyl) -1,1,1,3,3,3-hexafluoropropane, 2,3-diaminobicyclo [2.2.1] heptane, 2,5-diaminobicyclo [2.2.1] heptane, 2,6 -Diaminobicyclo [2.2.1] heptane, 2,7-diaminobicyclo [2.2.1] heptane, 2,5-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2,6 -Bis (aminomethyl) -bicyclo [2.2.1] heptane, 2,3-bis (aminomethyl) -bicyclo [2.2.1] heptane, 1,3-bis (aminomethyl) benzene, 1, 4-bis (aminomethyl) ) Benzene is preferable. In addition, the structural formula can be expressed as follows.

ここで、特に１，４−ジアミノシクロヘキサンが、複屈折発現性が優れており、好ましく使用できる。尚、構造式で表すと、以下の様に表せる。本発明者の推定によれば、１，４−ジアミノシクロヘキサンの様な剛直な構造が複屈折発現性が優れていると考えている。特にこの考えの元では、１，４−ジアミノシクロヘキサンの中でもｔｒａｎｓ体を用いることが好ましい。

Here, in particular, 1,4-diaminocyclohexane has excellent birefringence and can be preferably used. In addition, the structural formula can be expressed as follows. According to the inventor's estimation, a rigid structure such as 1,4-diaminocyclohexane is considered to have excellent birefringence. In particular, based on this idea, it is preferable to use a trans isomer among 1,4-diaminocyclohexane.

また、本発明のポリイミド樹脂層を好適に与えるポリイミド樹脂として前述の一般式（０）として、下記一般式（２）のユニットを例示することもできる。

Moreover, the unit of following General formula (2) can also be illustrated as above-mentioned General formula (0) as a polyimide resin which gives the polyimide resin layer of this invention suitably.

ここでＲ_２としてはイミド基が結合している炭素が芳香族炭素である炭化水素があげられるが、中でも、下記一般式群（３）で表される群から選ばれる１以上の構造であり、式中のＸは、Ｏ、ＳＯ_２、ＣＨ_２、Ｃ（ＣＨ_３）_２、Ｃ（ＣＦ_３）_２から選ばれる置換基であり、式中のＹはそれぞれ独立して、Ｈ、Ｆ、Ｃｌ、Ｂｒ，ＣＦ_３、ＣＣｌ_３、ＣＢｒ_３から選ばれる置換基であるものが好ましい。

Here, examples of R ₂ include hydrocarbons in which the carbon to which the imide group is bonded is an aromatic carbon. Among these, one or more structures selected from the group represented by the following general formula group (3). X in the formula is a substituent selected from O, SO ₂ , CH ₂ , C (CH ₃ ) ₂ , and C (CF ₃ ) ₂ , and Y in the formula independently represents H, F, Those which are substituents selected from Cl, Br, CF ₃ , CCl ₃ and CBr ₃ are preferred.

上記一般式（２）のユニットに構成するのに好適に使用される酸二無水物としては、３，４−ジカルボキシテトラリン−１−コハク酸二無水物があげられるが、一般式（１）の説明で例示したテトラカルボン酸二無水物を併用してもよい。

Examples of the acid dianhydride suitably used for constituting the unit of the general formula (2) include 3,4-dicarboxytetralin-1-succinic acid dianhydride, and the general formula (1) The tetracarboxylic dianhydride exemplified in the description of may be used in combination.

  Moreover, as a diamine used to constitute the unit of the general formula (2), a diamine to which the imide group is bonded is an aromatic carbon (hereinafter sometimes referred to as an aromatic diamine). Can be suitably used. Thus, by forming a polyimide resin containing an aromatic diamine, there is an effect of easily developing birefringence, and it can be suitably used when adjusting to a desired birefringence. For example, examples of the aromatic diamine include those similar to the aromatic diamine used to form the structure represented by the general formula (0). For example, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl, 2,2′-bis (trichloromethyl) -4 , 4'-diaminobiphenyl, 2,2'-bis (tribromomethyl) -4,4'-diaminobiphenyl, 2,2'-difluoro-4,4'-diaminobiphenyl, 2,2'-dichloro-4 , 4'-diaminobiphenyl, 2,2'-dibromo-4,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 4,4'-diamino-benzophenone, 9,9-bis (4-aminophenyl) Fluorene, 9,9-bis (4-amino-2-fluorophenyl) fluorene, 9,9-bis (4-amino-2-bromophenyl) fluorene, 9,9-bis (4-amino-2-alkyl) Rophenyl) fluorene, 9,9-bis (4-amino-3-fluorophenyl) fluorene, 9,9-bis (4-amino-3-bromophenyl) fluorene, 9,9-bis (4-amino-3- Chlorophenyl) fluorene, 9,9-bis (4-amino-2-trifluoromethylphenyl) fluorene, 9,9-bis (4-amino-3-trifluoromethylphenyl) fluorene, bis (4-aminophenyl) sulfone 1,4-diaminobenzene, 1,3-diaminobenzene, 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 2,2-bis (4-aminophenyl) ) -1,1,1,3,3,3-hexafluoropropane, 3,4'-diaminodiphenyl ether, etc. It is.

  Furthermore, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 2,2-bis (4-aminophenyl) -1,1,1,3,3,3 -Hexafluoropropane, 3,4'-diaminodiphenyl ether, bis (4-aminophenyl) sulfone, or 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (TFMB) introduced with a fluorine group ) Is preferable for the purpose of simultaneously imparting the solubility and birefringence of the polyimide resin, and more preferably 2,2′-bis (trifluoromethyl) -4,4 because of its particularly high solubility. '-Diaminobiphenyl (TFMB) can be used (the unit obtained using this can be represented by the following general formula (4)) Door can be.). For example, for a polyimide resin system in which only a specific high-boiling solvent such as an amide solvent such as NMP (2-methylpyrrolidone), DMF (N, N-dimethylformamide), or DMAc (N, N-dimethylacetamide) is dissolved By inserting a unit derived from TFMB, it can be made soluble in various low-boiling solvents, which is effective when using a coating method or the like.

一般式（２）のユニットを含有して形成されるポリイミド樹脂は一般式（２）単独でもよいが、一般式（１）と併用して使用することがより好ましい。

The polyimide resin formed containing the unit of the general formula (2) may be the general formula (2) alone, but is more preferably used in combination with the general formula (1).

For example, when a polyimide resin is formed using a unit represented by the general formula (1) and a unit represented by the following general formula (2) (however, other units may be included). When the mole fraction of the general formula (1) is represented by A and the mole fraction of the general formula (2) is represented by B,
0.10 ≦ A ≦ 0.50
0.50 ≦ B ≦ 0.90
(However, 0.6 ≦ A + B ≦ 1.0)
It is preferable that the relationship of
0.15 ≦ A ≦ 0.50
0.50 ≦ B ≦ 0.85
(However, 0.65 ≦ A + B ≦ 1.0)
It is preferable that

  When the molar fraction B is greater than 0.90, it is difficult to satisfy Formula 1, and it is likely to be a polyimide resin having a large retardation change amount from a long wavelength to a short wavelength in the visible light region, thereby achieving the object of the present invention. It becomes difficult. On the other hand, when the molar fraction B is smaller than 0.5, it is difficult to satisfy Formula 2, and it is difficult to obtain a polyimide resin having high birefringence. Also, when the content of B (for example, TFMB) is low, it is soluble in amide solvents such as DMF, but is a general low boiling point solvent (because it is easy to dry, it is effective when used as a coating resin. It is difficult to dissolve in (a).

  Moreover, in this invention, it is preferable to contain the unit represented by following General formula (7) as a compound represented by General formula (0).

（Ｒは、シクロブタンの炭素に結合しており、それぞれ独立した炭素数１〜１２の脂肪族基又は芳香族基である。Ｃは、２価の芳香族基又は脂肪族基を表す。）
一般式（７）を含有していれば、その他のユニットとしては特に制限されず、前述した一般式（０）で表されるその他の構造のものと複数のユニットを含んでいてもよい。また、中でも特に、本発明は、ポリイミド樹脂層を形成するポリイミド樹脂の構造が、一般式（７）で表されるユニットと、下記一般式（８）で表されるユニットを含有して形成されることがより好ましい。

(R is bonded to the carbon of cyclobutane and is an independent aliphatic group or aromatic group having 1 to 12 carbon atoms. C represents a divalent aromatic group or aliphatic group.)
If it contains General formula (7), it will not restrict | limit especially as another unit, The thing of the other structure represented by General formula (0) mentioned above and a plurality of units may be included. In particular, the present invention is formed by including the unit represented by the general formula (7) and the unit represented by the following general formula (8) in the structure of the polyimide resin forming the polyimide resin layer. More preferably.

（Ｄは、環を形成する炭素の半分以上が脂肪族炭素である環式を含み、カルボニル炭素が結合しているＤの炭素が脂肪族炭素である。ただし、置換または無置換のシクロブタン残基を除く。Ｃは前記に同じ。）
本明細書でいう「置換または無置換のシクロブタン残基を除く」とは、一般式（８）で表されるユニットを製造するために、テトラカルボン酸二無水物として、前述したシクロブタン環（二置換のシクロブタン環も含む）を含有するテトラカルボン酸二無水物を使用しないことを表す。

(D includes a cyclic group in which more than half of the carbons forming the ring are aliphatic carbons, and the carbon of D to which the carbonyl carbon is bonded is an aliphatic carbon, provided that a substituted or unsubstituted cyclobutane residue. (C is the same as above.)
As used herein, “excluding a substituted or unsubstituted cyclobutane residue” means that the above-mentioned cyclobutane ring (two dicarboxylic acids) is used as a tetracarboxylic dianhydride in order to produce a unit represented by the general formula (8). This means that no tetracarboxylic dianhydride containing a substituted cyclobutane ring is used.

  The acid dianhydride used in the formulas (7) and (8) includes a cyclobutane skeleton in the formula (7), but does not include a cyclobutane skeleton in the formula (2). This allows disordering and imparting solubility to the polyimide by incorporating different structures into the polyimide backbone. For this reason, the unit represented by the general formula (7) and the unit represented by the general formula (8) produced from a tetracarboxylic dianhydride having a sterically different structure from the substituted cyclobutanetetracarboxylic dianhydride. The polyimide resin layer containing is more preferable because solubility is imparted.

  As a method of forming the structures of the general formula (7) and the general formula (8), a diamine and tetracarboxylic dianhydride are reacted in the same manner as in the general formula (0) to synthesize a polyamic acid. Dehydration and ring closure can be made into a polyimide resin.

  The tetracarboxylic dianhydride that can be used in the general formula (7) is not particularly limited as long as it is a cyclobutane tetracarboxylic dianhydride containing two substituents having 1 to 12 carbon atoms. As a specific example, the same tetracarboxylic dianhydride containing a disubstituted cyclobutane ring exemplified as a tetracarboxylic dianhydride that can be used to form the structure represented by the general formula (0) is used. Can be mentioned. Further, tetracarboxylic dianhydrides containing a disubstituted cyclobutane ring may be used in combination of two or more. If they have two Rs, the configuration and position of substituents are particularly limited. It can also be used in the form of a mixture of various isomers. Further, their ratio is not particularly limited. In particular, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,4-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, or these The mixture is preferable for imparting both birefringence and solvent solubility to the polyimide resin obtained by synthesis.

  C represents a divalent aromatic group or aliphatic group, and may be one kind or plural kinds. Further, C used in the general formula (7) and C used in the general formula (8) may be different or the same, or may be one kind or plural kinds. The diamine containing C is not particularly limited as long as it is a diamine containing a divalent aromatic group or aliphatic group. The aromatic diamine can be used to form the general formula (0). The thing similar to what was illustrated as an aromatic diamine can be mention | raise | lifted as a specific example.

  In particular, 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 2,2-bis (4-aminophenyl) -1,1,1,3,3,3 Use of hexafluoropropane, 3,4'-diaminodiphenyl ether, bis (4-aminophenyl) sulfone, 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (TFMB) It is preferable for the purpose of simultaneously imparting the solubility of the polyimide resin, the birefringence and mechanical properties of the polyimide resin layer, and more preferably 2,2′-bis (trifluoromethyl) -4,4 because of its particularly high solubility. '-Diaminobiphenyl (TFMB) can be used.

  Specific examples of the aliphatic diamine include those similar to those exemplified as the aliphatic diamine that can be used to form the general formula (0).

  In particular, 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4′-diaminodicyclohexylmethane, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane 4,4'-diaminodicyclohexylpropane, bis (4-aminocyclohexyl) sulfone, 4,4'-diaminodicyclohexyl ether, 2,2'-dimethyl-4,4'-diaminodicyclohexane, 2,2'-bis (Trifluoromethyl) -4,4'-diaminodicyclohexane, 2,2'-bis (trichloromethyl) -4,4'-diaminodicyclohexane, 2,2'-bis (tribromomethyl) -4,4 '-Diaminodicyclohexane, 2,2'-difluoro-4,4'-diaminodicyclohexane, 2,2'-dic Loro-4,4'-diaminodicyclohexane, 2,2'-dibromo-4,4'-diaminodicyclohexane, 4,4'-diaminodicyclohexane, 2,2-bis (4-aminocyclohexyl)- 1,1,1,3,3,3-hexafluoropropane, 2,3-diaminobicyclo [2.2.1] heptane, 2,5-diaminobicyclo [2.2.1] heptane, 2,6- Diaminobicyclo [2.2.1] heptane, 2,7-diaminobicyclo [2.2.1] heptane, 2,5-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2,6- Bis (aminomethyl) -bicyclo [2.2.1] heptane, 2,3-bis (aminomethyl) -bicyclo [2.2.1] heptane, 1,3-bis (aminomethyl) benzene, 1,4 -Bis (aminomethyl) Zen is preferred in terms of value and birefringence values of Re (450) / Re (550).

  C is preferably one or more structures selected from the group represented by the following general formula group (12), and more preferably includes a structure represented by the following general formula (11) as an essential component.

Ｄは、環を形成する炭素の半分以上が脂肪族炭素である環式を含み、カルボニル炭素が結合しているＤの炭素が脂肪族炭素である。ただし、置換または無置換のシクロブタン残基を除いたものである。Ｄを形成するテトラカルボン酸二無水物としては、特に制限されるものでは無いが、１，２，３，４−シクロペンタンテトラカルボン酸二無水物、１，２，４，５−シクロへキサンテトラカルボン酸二無水物、ビシクロ[２，２，２] −オクタン−２，３，５，６−テトラカルボン酸二無水物、３，３´，４，４´−ビシクロヘキシルテトラカルボン酸二無水物、ビシクロ[２，２，1] −ヘプタン−２，３，５，６−テトラカルボン酸二無水物、２，３，４，５−テトラヒドロフランテトラカルボン酸二無水物は、溶媒溶解性の点で好ましく、３，３´，４，４´−ビシクロヘキシルテトラカルボン酸二無水物、ビシクロ[２，２，２] −オクタン−２，３，５，６−テトラカルボン酸二無水物がさらに好ましい。

D includes a cyclic structure in which more than half of the carbons forming the ring are aliphatic carbons, and the carbon of D to which the carbonyl carbon is bonded is an aliphatic carbon. However, a substituted or unsubstituted cyclobutane residue is excluded. The tetracarboxylic dianhydride that forms D is not particularly limited, but 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexane Tetracarboxylic dianhydride, bicyclo [2,2,2] -octane-2,3,5,6-tetracarboxylic dianhydride, 3,3 ′, 4,4′-bicyclohexyltetracarboxylic dianhydride Bicyclo [2,2,1] -heptane-2,3,5,6-tetracarboxylic dianhydride and 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride 3,3 ′, 4,4′-bicyclohexyltetracarboxylic dianhydride and bicyclo [2,2,2] -octane-2,3,5,6-tetracarboxylic dianhydride are more preferable. .

  Further, when the molar fractions of the general formula (7) and the general formula (8) are A1 and B1, 0.05 ≦ A1 ≦ 0.95, 0.05 ≦ B1 ≦ 0.95 (however, 0.10 ≦ A1 + B1 ≦ 1.00), more preferably 0.50 ≦ A1 ≦ 0.95 and 0.05 ≦ B1 ≦ 0.50 (provided that 0.55 ≦ A1 + B1 ≦ 1.00).

  As the general formula (7), a compound represented by the following general formula (9) in which R is a methyl group is preferable, and as the general formula (8), a compound represented by the following general formula group (10) is preferable. .

（式中、Ｃは前述の通りである。）
一方、本発明のポリイミド樹脂の重量平均分子量は、ＧＰＣのＰＥＧ（ポリエチレングリコール）換算で測定した値が２０，０００以上、２００，０００以下であることが好ましい。重量平均分子量が２０，０００未満では、耐久性に問題が生じることがある。また、重量平均分子量が２００，０００より大きい場合、有機溶媒への溶解性が低下するため、可溶性ポリイミド樹脂として有機溶媒へ溶解させて使用する用途では用いることが難しいことがある。

(In the formula, C is as described above.)
On the other hand, the weight average molecular weight of the polyimide resin of the present invention is preferably 20,000 or more and 200,000 or less as measured by GPC PEG (polyethylene glycol) conversion. If the weight average molecular weight is less than 20,000, there may be a problem in durability. Moreover, since the solubility to an organic solvent will fall when a weight average molecular weight is larger than 200,000, it may be difficult to use it for the use melt | dissolved and used for an organic solvent as a soluble polyimide resin.

  Moreover, it is preferable that the polyimide resin in this invention is soluble in various organic solvents. Here, the organic solvent is not particularly limited as long as it is a solvent that dissolves the polyimide resin. However, considering the case where the layer is formed by, for example, a coating method, the influence on the support film made of a polymer (for example, characteristics and It is preferable to use a material having a small amount of dissolution or swelling that impairs uniformity. For example, amide solvents such as NMP (2-methylpyrrolidone), DMF (N, N-dimethylformamide), DMAc (N, N-dimethylacetamide), ester solvents such as ethyl acetate, and halogen solvents such as chloroform and dichloromethane One or more solvents selected from solvents, ether solvents such as dioxolane and diethyl ether, ketone solvents such as MEK (methyl ethyl ketone), MIBK (methyl isobutyl ketone) and cyclohexanone, and aromatic hydrocarbon solvents such as toluene and xylene Particularly preferred is a polyimide resin that can be dissolved at a solid content concentration of 5% by weight or more (so-called soluble polyimide resin is preferred).

  On the other hand, it is preferable to use a low boiling point solvent having a boiling point of 120 degrees or less as a solvent used when using a coating method or the like. When such a low boiling point solvent is used, it becomes easy to reduce the amount of the volatile component remaining in the polyimide resin layer. For example, the content of the volatile component is 0.1% by weight or less, preferably 0.05. When the content is less than or equal to% by weight, it is difficult to cause a decrease in retardation value Rth in the thickness direction due to a decrease in volatile components during long-time use, and a polyimide resin layer having excellent durability can be provided. On the other hand, as long as the polyimide resin is dissolved, a non-solvent that does not normally dissolve the polyimide resin or a poor solvent that is difficult to dissolve may be used as a mixed solvent in a timely manner.

  The polyimide resin according to the present invention can be obtained by various methods using a solution dissolved in various organic solvents (in terms of film forming efficiency, preferably a solid content concentration of 5% by weight or more) by various methods. can do. For example, a method of forming a film once and then sticking it to a plastic film substrate to obtain a polyimide resin layer, a method of directly forming a layer on a plastic film substrate such as a coating layer (hereinafter sometimes referred to as a coating layer) Or a method in which a coating layer is once formed on a support and then transferred onto a plastic film substrate to form a layer (hereinafter sometimes referred to as a transfer method). In particular, the polyimide resin layer obtained in this way can be suitably used as an optical compensation member, for example. For example, TAC (triacetyl cellulose) or the like is used as the support film, and a polyimide resin can be coated on the support film to be used as an optical compensation member. Various materials can be used as the plastic film substrate, and examples thereof include polyester, polycarbonate, cycloolefin having an alicyclic structure, cellulose acylate, cellulose ether, polysulfone, polyarylate, and polystyrene.

  Here, the thickness of the polyimide resin layer to be formed is preferably 1 μm or more and less than 40 μm, and more preferably 1 μm or more and less than 20 μm. More preferably, it is 1 μm or more and less than 10 μm. By setting it as such thickness, when using as optical layers, such as an optical compensation member, the apparatus using this can be made thin. On the other hand, in order to achieve such a thickness, methods such as the coating method and the transfer method can be preferably used.

  Further, the polyimide resin layer can be stretched and used. When extending | stretching, it can also extend | stretch in the middle of film forming, and can also be extended after polyimide resin layer formation. As the stretching method, a known technique can be used in accordance with the intended use. For example, a method of stretching a polyimide resin layer alone in an atmosphere higher than the glass transition temperature of the polyimide resin layer, a temperature higher than the glass transition temperature of the polyimide resin layer together with the support after forming the polyimide resin layer on the support There is a method of stretching in an atmosphere. However, it is not essential that the polyimide resin layer is stretched in a temperature atmosphere higher than the glass transition temperature as long as required characteristics are exhibited. In addition, the substantial glass transition temperature of the polyimide resin layer at the time of extending | stretching may change with the solvent amount and additive amount contained in a polyimide resin layer. For this reason, it is preferable to determine in consideration of the influence.

  Although the usage application of the polyimide resin of this invention is not specifically limited, It can use suitably as an optical material. Also, optical applications that can be used particularly suitably include lens applications, communication optical waveguide applications, transparent substrate applications, optical compensation applications for liquid crystal display devices, and transparent electrode sealant applications. Among these, particularly when used as an optical compensation member for a liquid crystal display device or the like, it has a characteristic that a change amount of retardation from a long wavelength to a short wavelength is small in a visible light region (Re (450) / Re (550)). Is close to 1.00), the longer the wavelength, the greater the retardation value-the light leakage from the backlight during black display, etc., compared to using a polyimide resin with positive wavelength dispersion characteristics It is possible to reduce the decrease in contrast and gradation display.

  Next, the manufacturing method of a polyimide resin is demonstrated. The method for producing a polyimide resin generally includes three steps (1) formation of polyamic acid, (2) imidation of polyamic acid, and (3) extraction of polyimide resin (however, the method is not limited thereto). .) Hereinafter, these will be described with examples.

(1) Formation of polyamic acid The method for producing polyamic acid is not limited to the following method, and various methods can be used. An example is shown below.

  Disperse acid dianhydride in an organic solvent in which diamine is dissolved, and completely dissolve and polymerize by stirring. After dissolving and / or dispersing acid dianhydride in organic solvent, use diamine. There is a method of polymerizing by polymerization, a method of polymerizing by reacting a mixture of acid dianhydride and diamine in an organic solvent, but if the solubility of acid dianhydride in the organic solvent is poor, the organic solvent in which the diamine is dissolved It is preferable to disperse the acid dianhydride therein because the reaction proceeds uniformly.

  The reaction apparatus is preferably equipped with a temperature adjusting apparatus for controlling the reaction temperature, and the reaction solution temperature is preferably 60 ° C. or less, and more preferably 40 ° C. or less in terms of controlling the reaction.

  The organic solvent used for the polyamic acid polymerization is not particularly limited as long as the polyamic acid is dissolved and the polyamic acid polymerization reaction proceeds. For example, ureas such as tetramethylurea and N, N-dimethylethylurea are used. , Dimethyl sulfoxide, diphenyl sulfone, sulfoxide such as tetramethyl sulfone or sulfones, N, N-dimethylacetamide (DMAc), N, N-dimethylformamide (DMF), N, N′-diethylacetamide, N-methyl- Amides such as 2-pyrrolidone (NMP), γ-butyllactone, hexamethylphosphoric triamide, aprotic solvents such as phosphorylamides, alkyl halides such as chloroform and methylene chloride, aromatics such as benzene and toluene Group hydrocarbons, phenol, Examples include phenols such as resol, and ethers such as dimethyl ether, diethyl ether, and p-cresol methyl ether. Usually, these solvents are used alone, but two or more kinds are appropriately used in combination as necessary. Also good. Of these, amides such as DMF, DMAc and NMP are preferably used. Moreover, the organic solvent which can fully melt | dissolve the polyimide resin finally obtained is preferable.

  The weight% of the polyamic acid in the polyamic acid solution is preferably 5 to 50% by weight, and preferably 10 to 40% by weight in the organic solvent, from the viewpoint of handleability.

  Reaction molar ratio of acid dianhydrides and diamines used for polyamic acid polymerization (total number of moles of acid dianhydride used / total number of moles of diamine used) is 0.9 or more and 1.5 or less In the polyimide resin obtained from the polyamic acid solution, more preferably 0.95 or more and 1.3 or less, and particularly preferably 0.98 or more and 1.2 or less. It is preferable for reducing unreacted acid dianhydride and diamine.

(2) Imidization of polyamic acid A method for imidizing polyamic acid is described. Various known methods can be used as a method for imidizing the polyamic acid. For example, a thermal imidation method that thermally dehydrates and closes a ring or a chemical imidization method that uses a dehydrating agent can be used.

  The thermal imidization method is generally performed by adding an azeotropic solvent such as toluene azeotropically with water generated during the imidation reaction to the polyamic acid solution and then heating. In the thermal imidization method, an imidization accelerator can be used in combination.

  In general, the chemical imidization method is preferable in that the imidization reaction proceeds more easily than the thermal imidization method, the decomposition of the polyamic acid during heating is suppressed, and imidization can be performed.

In the chemical imidization method, it is preferable to use an imidization accelerator in that the reaction is completed in a short time.
As the imidization accelerator, various tertiary amines can be used. In particular, a polyimide resin having a high imidation ratio such as heterocyclic tertiary amines such as pyridine, 3-methyl-pyridine, quinoline, and isoquinoline. Is preferable in that it is obtained.

  Examples of the dehydrating agent used in the chemical imidization method include aliphatic acid anhydrides such as acetic anhydride and aromatic acid anhydrides. It is preferable to use acetic anhydride from the viewpoint that it is suitable for the precipitation step of the polyimide resin.

  The addition amount of the imidization accelerator relative to the polyamic acid is 0.5 to 5, more preferably 1 to 5, and more preferably 2 to 4 in terms of a molar ratio of the imidization accelerator / amide group in the polyamic acid. It is preferable to use it. If the molar ratio of the imidization accelerator / amide group in the polyamic acid is too small, imidation may not proceed sufficiently. On the other hand, if it is too large, although it depends on the poor solvent used in the precipitation of the polyimide resin powder, it tends to reduce the imidization rate.

  The addition amount of the dehydrating agent relative to the polyamic acid is preferably used so that the molar ratio of dehydrating agent / amide group in the polyamic acid is 1.2 to 4.0. If the amount of the dehydrating agent is less than 1.2 in terms of the molar ratio of the dehydrating agent / amide group in the polyamic acid, imidation may not proceed sufficiently. Conversely, the molar ratio of the dehydrating agent / amide acid in the polyamic acid If it is larger than 4, it may cause a decrease in molecular weight or coloring.

(3) Extraction of polyimide resin The precipitation method of imide resin is described. As a method for precipitating the polyimide resin from the solution containing the polyimide resin obtained as described in (1) and (2) above, various known methods can be selected. For example, polyimide resin, dehydrating agent, imidization promotion The polyimide resin can be obtained in a solid state by introducing a polyimide resin solution containing an agent or the like into the poor solvent of the polyimide resin, or by introducing the poor solvent into the polyimide resin solution. As a method of adding the poor solvent to the polyimide resin solution, there are a method of adding it in droplets or a method of adding it in a thread form, but there is no particular limitation as long as the polyimide resin is precipitated in the poor solvent. . The shape at the time of precipitation can be deposited in various forms such as a thread, a powder, and a flake. Further, these can be used after being pulverized if necessary.

  The poor solvent of the polyimide resin used in the present invention is not particularly limited, but is preferably mixed with a reaction solvent used as a solvent for dissolving the polyimide resin, for example, water, methyl alcohol, ethyl alcohol, isopropyl alcohol, Examples include ethylene glycol, triethylene glycol, 2-butyl alcohol, 2-propyl alcohol, 2-hexyl alcohol, cyclopentyl alcohol, cyclohexyl alcohol, phenol, and t-butyl alcohol. Among the above alcohols, secondary or tertiary alcohols such as isopropyl alcohol, 2-butyl alcohol, 2-pentyl alcohol, phenol, cyclopentyl alcohol, cyclohexyl alcohol, and t-butyl alcohol increase the imidization ratio of the resulting polyimide resin. From the viewpoint of stabilization, 2-propyl alcohol is more preferable. The amount of the poor solvent is preferably extracted in an amount of 2 times or more, more preferably 3 times or more of the polyimide resin solution.

  By simply depositing and separating the polyimide resin from the polyimide resin solution, it may be difficult to obtain a polyimide resin having a desired shape (a shape that is easily dissolved in an organic solvent) after drying. This is because the polyimide resin contains a large amount of reaction solvent. By washing the polyimide resin with the poor solvent, a desired polyimide resin containing almost no reaction solvent can be obtained.

  The method for drying the solidified resin solidified in the present invention may be vacuum drying or hot air drying. However, when used for optical purposes, coloring at the time of drying may be a problem, so it is desirable to carry out at 150 ° C. or lower.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited only to these Examples.

(Synthesis Example 1) Synthesis of dimethylcyclobutanetetracarboxylic anhydride (DMCBDA) Citraconic anhydride (305.1 g) and ethyl acetate (2.7 L) were charged into a reactor (3 L), and the mixture was stirred under an argon atmosphere. Then, it cooled to 8 degreeC and made it react with a high pressure mercury lamp (400W) for 8.5 hours, and the yellow cloudy solution was obtained. After removing the solvent of the yellow cloudy solution under reduced pressure (bath temperature 40 ° C.), the solid was washed with toluene (300 mL) for 1 hour, and a solid was obtained by filtration. The obtained solid was washed twice with toluene (100 mL) and dried under reduced pressure (room temperature, overnight) to obtain a crude DMCBDA (106.1 g. The obtained DMCBDA crude (106.1 g) was added to the reactor. Acetic anhydride (550 mL) was charged and dissolved in an argon atmosphere at 130 ° C., and then cooled to 5 ° C. After standing at 0 to 5 ° C. for 2 hours, the precipitated solid was filtered, acetic anhydride (25 mL), toluene The solid was washed with (100 mL), and the obtained solid was dried under reduced pressure (40 ° C., overnight) to obtain a DMCBDA solid (63.6 g) having two methyl groups in the cyclobutane ring.

(Example 1)
(1-1) Formation of Polyamic Acid A stirrer with a polytetrafluoroethylene seal stopper, a 300 mL glass separable flask equipped with a nitrogen inlet tube, and a reactor equipped with four blades as a stirring blade To produce a polyamic acid.

  In the above separable flask, 1.97 g (17.22 mmol) of trans-1,4-diaminocyclohexane (CHDA) and 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl (TFMB) 12 were added. .87 g (40.2 mmol) was added, 70.0 g of dehydrated N, N-dimethylformamide (DMF) was charged as a polymerization solvent and stirred, and then TDA (3,4-dicarboxytetralin-1 -17.234 g (57.0 mmol) of succinic dianhydride, manufactured by Shin Nippon Rika Co., Ltd., trade name Rikagit TDA-100) was added and stirred at a water temperature of 25 ° C. It was stirred at room temperature for 60 hours to obtain polyamic acid. In addition, the preparation density | concentration of the aliphatic diamine compound and aliphatic tetracarboxylic dianhydride in this reaction solution was 30 weight% with respect to all the reaction liquids.

(1-2) Imidization of polyamic acid After adding 14.56 g of DMF to the above solution, 21.38 g of 3-methyl-pyridine as an imidization catalyst (molar ratio of imidization accelerator / amide group in polyamic acid) = 2.0) was added and completely dispersed. In the dispersed solution, 14.063 g of acetic anhydride (molar ratio of dehydrating agent / amide in polyamic acid = 1.2) was added and stirred, heated at 100 ° C. for 20 minutes, and then returned to room temperature. Stirring was performed for 4 hours.

(1-3) Extraction of polyimide resin 300 ml of poor solvent 2-propyl alcohol was dropped into a polyimide resin solution from a dropping funnel having a hole diameter of about 5 mm into a polyimide resin solution stirred with a stirring blade for 200 revolutions or more. did. After dropping, the stirring blade was lowered to 100 revolutions and stirred for 20 minutes. After stirring, the rotation was stopped and the resin solid content was allowed to settle, and then the solvent was filtered. Further, the remaining resin solid component was washed with 300 ml of 2-propyl alcohol to remove dimethylformamide and 3-methyl-pyridine. After carrying out washing 5 times, it was dried by heating to 100 ° C. with a vacuum drying device and taken out as a polyimide resin.

(Evaluation methods)
(Chromatic dispersion of retardation value)
The obtained polyimide resin is dissolved in DMF to prepare a polyimide resin solution containing 25% by weight of polyimide resin, and a polyimide resin solution film having a uniform film thickness on a pineapple cover glass (35 × 50 mm). After coating, it was dried at 90 ° C. for 20 minutes and further dried at 200 ° C. for 20 minutes.

  This coated sample is measured for wavelength dispersion of phase difference by automatic birefringence meter KOBRA-wR manufactured by Oji Scientific Instruments, and Re (450) and Re (550) are calculated based on the measured value by the program attached to the device. did.

  Table 2 shows the retardation value Re (λ) when incident from an oblique direction (incident angle 40 °).

(Birefringence)
The birefringence (Δn) in the present invention is a value represented by Formula 1 when the in-plane refractive index of the polyimide layer is nx and ny and the refractive index in the thickness direction is nz.
Δn = [(nx + ny) / 2] −nx Equation 1
Birefringence is measured by using Kobra-WR to measure the phase difference of light incident at an angle of 40 ° when the vertical direction of the polyimide layer is 0 °. Kobra-RE (Prince measurement) The birefringence (Δn) was calculated from the refractive index obtained in (1).

(Molecular weight)
The weight average molecular weight (Mw) was evaluated under the following conditions. The evaluation results are shown in Table 2.

（実施例２）
ジアミンの割合をＣＨＤＡ：ＴＦＭＢ＝５０．０％：５０．０％として、ＣＨＤＡ３．５６ｇ（３１．２ミリモル）、ＴＦＭＢ９．９８ｇ（３１．２ミリモル）、ＴＤＡ１８．７１ｇ（６２．０ミリモル）用いること以外は実施例１と同様にして製造した。

(Example 2)
CHDA 3.56 g (31.2 mmol), TFMB 9.98 g (31.2 mmol), TDA 18.71 g (62.0 mmol) are used with the ratio of diamine being CHDA: TFMB = 50.0%: 50.0%. Except for this, it was produced in the same manner as in Example 1.

  Evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 2.

(Example 3)
(3-1) Formation of polyamic acid A stirrer with a polytetrafluoroethylene seal stopper, a 300 mL glass separable flask equipped with a nitrogen inlet tube, and a reactor equipped with four blades as a stirring blade To produce a polyamic acid.

  In the above separable flask, 0.91 g (8.0 mmol) of trans-1,4-diaminocyclohexane (CHDA) and 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl (TFMB) 10 .13 g (31.6 mmol) was added, and 46.7 g of dehydrated N, N-dimethylformamide (DMF) was charged as a polymerization solvent and stirred, and then bicyclo [2,2,2] -octane- was added to this solution. 1.00 g (4.0 mmol) of 2,3,5,6-tetracarboxylic dianhydride (BTA-H) and 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride (DMCBDA) 7.98 g (35.6 mmol) was added, and the mixture was stirred in a 25 ° C. water bath. It was stirred for 146 hours to obtain polyamic acid. In addition, the preparation density | concentration of the aliphatic diamine compound and aliphatic tetracarboxylic dianhydride in this reaction solution was 30 weight% with respect to all the reaction liquids.

(3-2) Imidization of polyamic acid After adding 11.1 g of DMF to the above solution, 12.5 g of pyridine as an imidization catalyst (molar ratio of imidization accelerator / amide group in polyamic acid = 2.0) And 9.7 g of acetic anhydride (dehydrating agent / molar ratio of amide groups in polyamic acid = 1.2) were added and stirred, and the mixture was stirred at room temperature for 4 hours.

(3-3) Extraction of polyimide resin 300 mL of 2-propyl alcohol was dropped into the polyimide resin solution from the dropping funnel into the polyimide resin solution stirred with a stirring blade for 200 revolutions or more. After dropping, the stirring blade was lowered to 100 revolutions and stirred for 20 minutes. After stirring, the rotation was stopped and the resin solid content was allowed to settle, and then the solvent was filtered. Further, the remaining resin solid component was washed five times with 300 mL of 2-propyl alcohol, and then dried by heating to 100 ° C. with a vacuum dryer, and taken out as a polyimide resin.

(Evaluation methods)
(Chromatic dispersion of retardation value)
The obtained polyimide resin is dissolved in cyclopentanone to prepare a polyimide resin solution containing 15% by weight of the polyimide resin, and the polyimide resin solution having a uniform film thickness on a pineapple cover glass (35 × 50 mm). After coating as a film, it was dried at 130 ° C. for 60 minutes.
The coated sample was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

(Birefringence)
Evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 2.

(Molecular weight)
Evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 2.

Example 4
As the diamine, 1.60 g (7.6 mmol) of 4,4′-diaminodicyclohexylmethane (DCHM) and 9.76 g (30.5 mmol) of TFMB were used, and 0.97 g (3. 9 mmol), and DMCBDA 7.70 g (34.3 mmol) synthesized in Synthesis Example 1 was used, and the polyamic acid was formed (stirred) for 116 hours. Evaluation was performed in the same manner as in Example 3. The evaluation results are shown in Table 2.

(Example 5)
11.71 g (36.6 mmol) of TFMB was used as the diamine, 0.92 g (3.7 mmol) of BTA-H was used as the acid dianhydride, and 7.39 g (33.0 mmol) of DMCBDA synthesized in Synthesis Example 1 was used. This was produced in the same manner as in Example 3 except that the formation time (stirring) of the polyamic acid was changed to 293 hours. Evaluation was performed in the same manner as in Example 3. The evaluation results are shown in Table 2.

(Example 6)
TFMB9.80 (30.6 mmol) and 4,4′-diaminodiphenyl ether (ODA) 1.53 g (7.6 mmol) were used as the diamine, and BTA-H 0.97 g (3.9) was used as the acid dianhydride. Mmol) and 7.73 g (34.5 mmol) of DMCBDA synthesized in Synthesis Example 1 were used and the production (stirring) time of polyamic acid was changed to 146 hours. Evaluation was performed in the same manner as in Example 3. The evaluation results are shown in Table 2.

(Example 7)
As diamine, 9.69 g (30.3 mmol) of TFMB and 1.52 g (7.6 mmol) of ODA were used, and 3,3 ′, 4,4′-bicyclohexyltetracarboxylic dianhydride ( Example 1 except that 1.16 g (3.8 mmol) of H-BPDA) and 7.63 g (34.1 mmol) of DMCBDA synthesized in Synthesis Example 1 were used and the polyamic acid formation (stirring) time was 130 hours. 3 was produced in the same manner as in No. 3. Evaluation was performed in the same manner as in Example 3, and the birefringence was 0.056.

(Comparative Example 1)
Manufactured in the same manner as in Example 1 except that the ratio of diamine is CHDA: TFMB = 0.0%: 100.0% and TFMB 16.44 (51.3 mmol) and TDA 15.41 (51.3) are used. did.

  Evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 2.

(Comparative Example 2)
The ratio of diamine was CHDA: TFMB = 100.0%: 0.0%, CHDA 9.05 g (79.3 mmol) was used, and dehydrated N, N-dimethylformamide (DMF) 55.24 g was used as a solvent for polymerization. 14.77 g (158.5 mmol) of β-picoline was added and stirred, and then 23.80 g (79.3 mmol) of TDA was added to the solution, followed by stirring at a water temperature of 25 ° C. It was stirred at room temperature for 6 hours to obtain polyamic acid. The following operations were carried out in the same manner as in Example 1.

  Evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 2.

(Comparative Example 3)
Evaluation similar to Example 1 was performed using 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropanoic acid dianhydride (6FDA) as the acid dianhydride and TFMB as the diamine.

Method of measuring retardation value (Re (λ))

Claims (18)

The polyimide resin layer characterized by satisfy | filling following Numerical formula 1 and following Numerical formula 2.
1.00 ≦ Re (450) / Re (550) ≦ 1.05: Formula 1
(Re (λ) is a layer formed by using a polyimide resin with the horizontal plane as the reference plane, and is inclined with respect to the reference plane by 40 ° about the fast axis of the layer, while the wavelength λnm (In-plane retardation (nm) in a plane inclined by 40 ° with respect to the plane on which the layer is formed, measured by irradiating measurement light from the direction perpendicular to the reference plane.)
0.010 ≦ Δn ≦ 0.060: Formula 2
(Here, birefringence (Δn) is the refractive index in the plane inclined by 40 ° with respect to the plane on which the polyimide layer is formed in the same manner as described above, nx and ny, and the refractive index in the direction perpendicular to this plane is nz. In this case, Δn = [(nx + ny) / 2] −nx.) The polyimide resin layer according to claim 1, comprising a unit represented by the following general formula (0).

(Q includes a ring in which more than half of the carbons forming the ring are aliphatic carbons, and the carbon of Q to which the carbonyl carbon is bonded is an aliphatic carbon. P is a divalent aromatic group or aliphatic carbon. A group.) The polyimide resin layer according to claim 1 or 2, wherein the polyimide resin layer is formed by containing a unit represented by the following general formula (1) and / or a unit represented by the following general formula (2). .

(Here, R ₁ is composed of a hydrocarbon having 1 to 20 carbon atoms, the carbon to which the imide group is bonded is aliphatic carbon, and R ₂ is the carbon to which the imide group is bonded is aromatic. It is a hydrocarbon that is carbon.) The polyimide resin layer according to claim 3, wherein the general formula (2) is the following general formula (4).

When the mole fraction of the unit represented by the general formula (1) is represented as A and the mole fraction of the unit represented by the general formula (2) is represented as B,
0.10 ≦ A ≦ 0.50
and,
0.50 ≦ B ≦ 0.90
5 (provided that 0.6 ≦ A + B ≦ 1.0). 5. The polyimide resin layer according to claim 3, wherein: 6. The unit represented by the general formula (1), wherein R ₁ is one or more structures selected from the group represented by the general formula group (5). The polyimide resin layer described in 1.

(Wherein, X is a substituent selected from O, SO ₂ , CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , and Y in the formula is independently H, This is a substituent selected from F, Cl, Br, CF ₃ , CCl ₃ and CBr _3. ) In the unit represented by the general formula (1), the polyimide resin layer according to any one of claims 3-6, wherein R ₁ is a structure represented by the general formula (6).

When the mole fraction of the unit represented by the general formula (1) is represented as A and the mole fraction of the unit represented by the general formula (2) is represented as B,
0.15 ≦ A ≦ 0.50
and,
0.50 ≦ B ≦ 0.85
The polyimide resin layer according to claim 7, wherein: 0.65 ≦ A + B ≦ 1.0. The polyimide resin layer according to claim 1, wherein the polyimide resin layer is formed by containing a unit represented by the following general formula (7).

(R is bonded to the carbon of cyclobutane and is an independent aliphatic group or aromatic group having 1 to 12 carbon atoms. C represents a divalent aromatic group or aliphatic group.) The polyimide resin layer according to claim 9, further comprising a unit represented by the following general formula (8).

(D includes a cyclic group in which more than half of the carbons forming the ring are aliphatic carbons, and the carbon of D to which the carbonyl carbon is bonded is an aliphatic carbon, provided that a substituted or unsubstituted cyclobutane residue. (C is the same as above.)   The polyimide resin layer according to claim 9 or 10, wherein in the unit represented by the general formula (7), R is a methyl group. The polyimide resin layer according to claim 10 or 11, wherein the polyimide resin layer is formed by containing a unit represented by the following general formula (9) and a unit represented by the following general formula group (10).

(C represents a divalent aromatic group or an aliphatic group.)   Thickness is 1 micrometer or more and less than 40 micrometers, The polyimide resin layer of any one of Claims 1-12 characterized by the above-mentioned.   A laminate comprising the polyimide resin layer according to any one of claims 1 to 13 and a plastic film substrate.   A method for producing a laminate, wherein the laminate according to claim 14 is formed by applying and drying a polyimide resin layer on a plastic film substrate.   A method for producing a laminate, wherein the laminate according to claim 14 is formed by transferring a polyimide resin layer on a plastic film substrate.   An optical compensation member comprising the polyimide resin layer or laminate according to any one of claims 1 to 16. A dimethylformamide solution having a polyimide resin solid component concentration of 25% by weight was applied on a glass substrate, dried at 90 ° C. for 20 minutes, and further dried at 200 ° C. for 20 minutes. The polyimide resin characterized by satisfying the following mathematical formula 3 and the following mathematical formula 4.
1.00 ≦ Re (450) / Re (550) ≦ 1.05: Formula 3
(Re (λ) is a layer formed by using a polyimide resin with the horizontal plane as the reference plane, and is inclined with respect to the reference plane by 40 ° about the fast axis of the layer, while the wavelength λnm (In-plane retardation (nm) in a plane inclined by 40 ° with respect to the plane on which the layer is formed, measured by irradiating measurement light from the direction perpendicular to the reference plane.)
0.010 ≦ Δn ≦ 0.060: Formula 4
(Here, birefringence (Δn) is the refractive index in the plane inclined by 40 ° with respect to the plane on which the polyimide layer is formed in the same manner as described above, nx and ny, and the refractive index in the direction perpendicular to this plane is nz. In this case, Δn = [(nx + ny) / 2] −nx.)

Images