KR102386047B1 - Polyimide film and copper-clad laminate - Google Patents

Abstract

[Problem] To provide a polyimide film capable of reducing dimensional change during high-temperature processing, and a copper-clad laminate using the same.
[Solutions] A polyimide film having a thermoplastic polyimide layer on at least one of the non-thermoplastic polyimide layers, wherein (i) the coefficient of thermal expansion is within the range of 10 to 30 ppm/K; (ii) the glass transition temperature of the thermoplastic polyimide is within the range of 200°C or higher and 350°C or lower; (iii) the value of in-plane retardation (RO) is within the range of 5 nm or more and 50 nm or less; (iv) The deviation (ΔRO) of RO in the width direction (TD direction) satisfies 10 nm or less.

Description

POLYIMIDE FILM AND COPPER-CLAD LAMINATE

The present invention relates to a polyimide film and a copper clad laminate.

In recent years, with the progress of miniaturization, weight reduction, and space saving of electronic devices, the demand for flexible printed circuit boards (FPCs) that are thin, light, flexible, and have excellent durability even after repeated bending is increasing. . Since FPC can be mounted in a three-dimensional and high-density even in a limited space, its use is being expanded to parts such as wiring, cables, and connectors of movable parts of electronic devices such as HDDs, DVDs, and mobile phones, for example.

FPC is manufactured by etching the copper layer of the copper clad laminate (CCL) and processing the wiring. Rolled copper foil is widely used as a material of a copper layer for FPC which is continuously bent or bent by 180 degrees in a mobile phone or a smart phone. For example, in Patent Document 1, a proposal is made in which the bending resistance of a copper clad laminate manufactured using rolled copper foil is prescribed by the number of bending resistance. In addition, in Patent Document 2, a copper-clad laminate using a rolled copper foil defined by glossiness and number of bending is proposed.

In the photolithography process or FPC mounting process for the copper-clad laminate, various processes such as bonding, cutting, exposure, and etching are performed based on the alignment marks installed on the copper-clad laminate. Machining precision in these processes becomes important for maintaining the reliability of electronic devices equipped with FPCs. However, since the copper clad laminate has a structure in which a copper layer and a resin layer having different coefficients of thermal expansion are laminated, stress is generated between the layers due to the difference in the coefficients of thermal expansion of the copper layer and the resin layer. This stress is released when a part or all of the copper layer is etched to form wiring, thereby causing expansion and contraction, and changing the dimensions of the wiring pattern. Therefore, a dimensional change occurs in the final stage of FPC, which causes a defective connection between wirings or between wirings and terminals, thereby reducing the reliability and yield of the circuit board. Therefore, dimensional stability is a very important characteristic for a copper clad laminate as a circuit board material. However, in Patent Document 1 and Patent Document 2, the dimensional stability of the copper-clad laminate is not considered at all.

As a method for producing a polyimide film, a method of orienting polyimide molecular chains to exhibit in-plane birefringence by simultaneously or sequentially performing uniaxial stretching and thermal imidization on a self-supporting gel film of polyamic acid is known. there is. At this time, in order to control retardation, conditions, such as a uniaxial stretching operation and the temperature increase rate at the time of thermal imidation, a final curing temperature, and a load, are controlled with high precision. For example, in patent document 3, the technique of controlling retardation by uniaxial stretching heating a polyimide film is proposed.

Japanese Patent Laid-Open No. 2014-15674 (claims, etc.) Japanese Patent Laid-Open No. 2014-11451 (Scope of Claims, etc.) Japanese Patent Laid-Open No. 2000-356713 (claims, etc.)

A first object of the present invention is to provide a polyimide film capable of reducing dimensional change during high-temperature processing, and a copper-clad laminate using the same. A second object of the present invention is to provide a polyimide film capable of realizing high dimensional stability precision and stably producing even in a heating environment above the glass transition temperature of the thermoplastic polyimide, and a copper-clad laminate using the same.

MEANS TO SOLVE THE PROBLEM The present inventors discovered that the said subject was solvable by controlling in-plane retardation of a polyimide film, as a result of earnestly examining, and came to complete this invention.

That is, the polyimide film of this invention is a polyimide film which has a thermoplastic polyimide layer which consists of a thermoplastic polyimide on at least one of the non-thermoplastic polyimide layer which consists of a non-thermoplastic polyimide. The polyimide film of the present invention has the following conditions (i) to (iv);

(i) the coefficient of thermal expansion is within the range of 10 ~ 30ppm / K;

(ii) the glass transition temperature of the thermoplastic polyimide is in the range of 200 °C or more and 350 °C or less;

(iii) the value of in-plane retardation (RO) exists in the range of 5 nm or more and 50 nm or less;

(iv) It is characterized in that it satisfies that the deviation (ΔRO) of the in-plane retardation RO in the width direction (TD direction) is 10 nm or less.

20 nm or less may be sufficient as the change amount of in-plane retardation (RO) in the polyimide film of this invention before and behind pressurization for a pressure of 340 MPa/m<2>, and 15 minutes of holding time under the environment of temperature 360 degreeC.

In the polyimide film of the present invention, the non-thermoplastic polyimide includes a tetracarboxylic acid residue and a diamine residue, the tetracarboxylic acid residue and the diamine residue are both aromatic groups, and the aromatic group is a biphenyltetrayl group or a biphenyl group. It contains a lene group, and 40 mol part or more of the said biphenyltetrayl group or a biphenylene group may be sufficient with respect to a total of 100 mol part of the said tetracarboxylic acid residue and a diamine residue.

In the polyimide film of the present invention, the thermoplastic polyimide includes a tetracarboxylic acid residue and a diamine residue, the tetracarboxylic acid residue and the diamine residue are both aromatic groups, and the aromatic group is a biphenyltetrayl group or a biphenyl group. It contains a lene group, and the said biphenyltetrayl group or a biphenylene group may exist in the range of 30 mol part or more and 80 mol part or less with respect to a total of 100 mol part of the said tetracarboxylic acid residue and a diamine residue.

The polyimide film of the present invention is a tetracarboxylic acid derived from an anhydride of 3,3',4,4'-biphenyltetracarboxylic acid based on 100 parts by mole of the total tetracarboxylic acid residues contained in the non-thermoplastic polyimide. The acid residue may exist in the range of 20 mol part or more and 70 mol part or less.

The polyimide film of the present invention contains tetracarboxyl derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride based on 100 parts by mole of the total tetracarboxylic acid residues contained in the thermoplastic polyimide. The acid residue may be 40 molar parts or more.

In the polyimide film of the present invention, 20 mol parts or more of the diamine residues represented by the following general formula (1) may be 20 mol parts or more with respect to 100 mol parts of all the diamine residues contained in the non-thermoplastic polyimide.

[Wherein, R ₁ and R ₂ independently represent an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or an alkenyl group having 2 to 3 carbon atoms which may be substituted with a halogen atom or a phenyl group.]

In the polyimide film of the present invention, the diamine residue represented by the following general formula (2) may be in the range of 3 mole parts or more and 60 mole parts or less with respect to 100 mole parts of all the diamine residues contained in the thermoplastic polyimide.

[Wherein, R ₃ and R ₄ independently represent an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or an alkenyl group which may be substituted with a halogen atom or a phenyl group.]

The copper-clad laminate of the present invention is a copper-clad laminate including an insulating layer and a copper layer on at least one surface of the insulating layer. And, the copper-clad laminate of the present invention has a thermoplastic polyimide layer in which the insulating layer is in contact with the surface of the copper layer, and a non-thermoplastic polyimide layer indirectly laminated,

The insulating layer is characterized in that it consists of any one of the polyimide films above.

In the copper-clad laminate of the present invention, both the amount of dimensional change in the longitudinal direction (MD direction) and the amount of dimensional change in the width direction (TD direction) before and after etching the copper layer may be 2% or less.

The polyimide film of the present invention is excellent in dimensional stability even when the amount of retardation change is suppressed even in a high temperature and high pressure environment, for example, even when thermocompression bonding with copper foil at a high temperature. Therefore, by using the polyimide film of this invention, the time in the manufacturing process of a copper clad laminated board can be shortened, and it is excellent in production stability. In particular, even when a wide polyimide film is processed by a roll-to-roll process and copper foil is laminated to produce a copper-clad laminate, the dimensional change rate is low in the entire width of the film and the dimensional stability is obtained from the copper-clad laminate. The FPC can be made capable of high-density mounting. Therefore, by using the polyimide film of the present invention and a copper-clad laminate using the same as an FPC material, it is possible to improve the reliability and yield of the circuit board.

1 is a perspective view showing a schematic configuration of a copper-clad laminate and a test piece used in an evaluation method for evaluating dimensional stability of a copper-clad laminate according to an embodiment of the present invention.
It is a figure explaining the mark position in a test piece.
3 is a partially enlarged view of the central region of the test piece.
4 is a partially enlarged view of a corner region of a test piece.
It is a figure explaining the dimensional change amount of the space|interval of a hole and a hole.
It is a figure used for description of the evaluation sample in an Example.
It is a figure used for description of preparation of the evaluation sample in an Example.

Next, embodiment of this invention is described, referring drawings suitably.

<Polyimide film>

The polyimide film of this embodiment has a thermoplastic polyimide layer in at least one of a non-thermoplastic polyimide layer. That is, the thermoplastic polyimide layer is formed on one or both surfaces of the non-thermoplastic polyimide layer. For example, in the case of a copper-clad laminate composed of the polyimide film and copper layer of the present embodiment, the copper layer is laminated on the surface of the thermoplastic polyimide layer.

Here, the non-thermoplastic polyimide is generally a polyimide that does not show softening or adhesiveness even when heated, but in the present invention, the storage modulus at 30°C measured using a dynamic viscoelasticity measuring device (DMA) is 1.0×10 It is ⁹ Pa or more and refers to the polyimide whose storage modulus in 360 degreeC is 1.0x10< ⁸ >Pa or more. In addition, the thermoplastic polyimide is generally a polyimide whose glass transition temperature (Tg) can be clearly confirmed, but in the present invention, the storage modulus at 30° C. measured using DMA is 1.0×10 ⁹ Pa or more, , refers to a polyimide having a storage modulus of less than 1.0×10 ⁸ Pa at 360°C.

The polyimide film of the present embodiment may be a film (sheet) or may be a film in a state of being laminated on a base material such as a resin sheet such as a copper foil, a glass plate, a polyimide film, a polyamide film, or a polyester film.

The polyimide film of the present embodiment has a coefficient of thermal expansion (CTE) of 10 ppm/K or more and 30 ppm/K or less in order to prevent occurrence of warpage or a decrease in dimensional stability when applied as an insulating layer of a circuit board, for example. It is important that it exists in the range, Preferably the inside of the range of 10 ppm/K or more and 25 ppm/K or less is good. If CTE is less than 10 ppm/K or exceeds 30 ppm/K, warpage may occur or dimensional stability will fall. Further, in the polyimide film of this embodiment, the CTE of the polyimide film is more preferably within the range of ±5 ppm/K or less with respect to the CTE of the copper layer made of copper foil or the like, and the inside of the range of ±2 ppm/K or less is the most desirable.

The polyimide film of this embodiment WHEREIN: The thickness of a polyimide film can be set to the thickness within a predetermined range according to the purpose of use. It is preferable to exist in the range of 8-50 micrometers, for example, and, as for the thickness of a polyimide film, it is more preferable to exist in the range of 11-26 micrometers. If the thickness of the polyimide film does not satisfy the lower limit, problems such as electrical insulation cannot be guaranteed or handling in the manufacturing process is difficult due to a decrease in handling properties may occur. On the other hand, when the thickness of the polyimide film exceeds the upper limit, it is necessary to control the manufacturing conditions with high precision in order to control the in-plane retardation (RO), and problems such as a decrease in productivity occur.

The polyimide film of this embodiment WHEREIN: The non-thermoplastic polyimide layer comprises the polyimide layer of low thermal expansibility, and the thermoplastic polyimide layer comprises the polyimide layer of high thermal expansibility. Here, the low thermal expansion polyimide layer preferably has a coefficient of thermal expansion (CTE) within the range of 1 ppm/K or more and 25 ppm/K or less, more preferably 3 ppm/K or more and 25 ppm/K or less. . Further, the polyimide layer having high thermal expansibility has a CTE of preferably 35 ppm/K or more, more preferably 35 ppm/K or more and 80 ppm/K or less, still more preferably 35 ppm/K or more and 70 ppm/K or less. polyimide layer. A polyimide layer can be set as the polyimide layer which has a desired CTE by changing suitably the combination of the raw material used, thickness, and drying/hardening conditions.

Moreover, in the polyimide film of this embodiment, it is good that the thickness ratio (non-thermoplastic polyimide layer/thermoplastic polyimide layer) of a non-thermoplastic polyimide layer and a thermoplastic polyimide layer exists in the range of 1.5-6.0. If the value of this ratio does not satisfy 1.5, the non-thermoplastic polyimide layer with respect to the entire polyimide film becomes thin, so the variation in in-plane retardation (RO) tends to become large. If the value exceeds 6.0, the thermoplastic polyimide layer becomes thin because the polyimide The adhesion reliability of a mid film and a copper layer falls easily. Control of this in-plane retardation (RO) correlates with the resin composition of each polyimide layer which comprises a polyimide film, and its thickness. As the thickness of the thermoplastic polyimide layer, which is a resin composition imparted with adhesiveness, that is, high thermal expansibility or softening, increases, the RO value of the polyimide film is greatly affected. Then, the ratio of the thickness of a non-thermoplastic polyimide layer is made large, the ratio of the thickness of a thermoplastic polyimide layer is made small, and the value of RO of a polyimide film and its dispersion|variation are made small.

The polyimide film of this embodiment WHEREIN: The polyimide which comprises a thermoplastic polyimide layer can improve adhesiveness with a copper layer. Such a thermoplastic polyimide has a glass transition temperature in the range of 200°C or more and 350°C or less, preferably 200°C or more and 320°C or less.

From the viewpoint of further expressing the effect of improving the dimensional accuracy of the polyimide film of the present embodiment, the polyimide film of the present embodiment has a film width in the range of 490 mm or more and 1,100 mm or less, and has an elongated length of 20 m or more. it is preferable When the polyimide film of this embodiment is manufactured continuously, the effect of invention becomes especially remarkable, so that the width direction (it is also mentioned TD direction hereafter) is a wide film. In addition, after the polyimide film of this embodiment is continuously manufactured, the film slit to any fixed value in the longitudinal direction (hereinafter also referred to as MD direction) and TD direction of a long polyimide film is also included.

The polyimide film of the present embodiment has an in-plane retardation (RO) of 5 nm or more and 50 nm or less, preferably 5 nm or more and 20 nm or less, More preferably 5 nm or more and 15 nm or less is within the scope of In addition, the deviation (ΔRO) of RO in the TD direction is 10 nm or less, preferably 5 nm or less, more preferably 3 nm or less, and by being controlled within this range, the dimensional accuracy is particularly accurate even for a film having a thickness of 25 µm or more. is set to be high.

The polyimide film of this embodiment, Preferably, the change amount of in-plane retardation (RO) in the environment of temperature 360 degreeC, pressure 340 MPa/m<2>, before and behind pressurization for 15 minutes of holding time is 20 nm or less, More preferably is 10 nm or less, more preferably 5 nm or less. As for the polyimide film of this embodiment, even if it is a temperature exceeding the glass transition temperature of the polyimide which comprises a thermoplastic polyimide layer, the change amount of RO is controlled below the said upper limit. Therefore, since RO does not change easily also before and after the process of bonding the polyimide film of this embodiment and copper foil by thermal lamination, for example, it becomes a polyimide film excellent in dimensional stability.

Moreover, it is preferable to exist in the range of 3.0-10.0 GPa, and, as for the tensile modulus of elasticity of the polyimide film of this embodiment, it is more preferable to exist in the range of 4.5-8.0 GPa. When the tensile modulus of elasticity of the polyimide film satisfies 3.0 GPa, the strength of the polyimide itself is lowered, so that handling problems such as tearing of the film may occur when processing the copper clad laminate into a circuit board. Conversely, when the tensile modulus of elasticity of the polyimide film exceeds 10.0 GPa, as a result of the increase in the bending rigidity of the copper-clad laminate, the bending stress applied to the copper wiring when the copper-clad laminate is bent increases and the bending resistance decreases. By setting the tensile modulus of elasticity of the polyimide film within the above range, the strength and flexibility of the polyimide film are ensured.

As a form of the manufacturing method of the polyimide film of this embodiment, for example, [1] A method of manufacturing a polyimide film by applying and drying a solution of polyamic acid to a supporting substrate and then imidizing it, [2] supporting substrate After apply|coating and drying the solution of polyamic acid, there exists a method of peeling the gel film of polyamic acid from a support base material, imidating it, and manufacturing a polyimide film. In addition, since the polyimide film of this embodiment is a polyimide film which consists of a polyimide layer of multiple layers, as a form of the manufacturing method, for example, [3] Applying|coating and drying a polyamic acid solution to a support base material is Method of imidization after repeating multiple times (hereinafter, casting method), [4] Method of imidization after coating and drying in a state in which polyamic acid is simultaneously laminated in multiple layers by multilayer extrusion (hereinafter referred to as multilayer extrusion method) ) and the like are exemplified.

The method of said [1], for example, following process (1a) - process (1c);

(1a) applying a solution of polyamic acid to a supporting substrate and drying;

(1b) forming a polyimide layer by heat-treating polyamic acid to imidize it on a supporting substrate;

(1c) The process of obtaining a polyimide film by isolate|separating a support base material and a polyimide layer can be included.

The method of said [2] includes, for example, the following steps (2a) to (2c);

(2a) applying a solution of polyamic acid to a supporting substrate and drying;

(2b) separating the support substrate and the polyamic acid gel film;

(2c) heat-treating the gel film of polyamic acid to imidize it, and it may include the process of obtaining a polyimide film.

In the method of [3], in the method of [1] or [2], the step (1a) or the step (2a) is repeated a plurality of times to form a polyamic acid laminate structure on the supporting substrate. Except for the above, it can be carried out in the same manner as in the method of [1] or [2].

In the method of [4], in the step (1a) of the method of [1] or the step (2a) of the method [2], the laminated structure of polyamic acid is simultaneously applied by multilayer extrusion and dried Except for the above, it can be carried out in the same manner as in the method of [1] or [2].

The polyimide film produced in the present invention preferably completes imidization of the polyamic acid on the supporting substrate. Since the resin layer of polyamic acid is imidated in the state fixed to the support base material, the expansion-contraction change of the polyimide layer in the imidation process can be suppressed, and the thickness and dimensional accuracy of a polyimide film can be maintained.

However, the polyimide film in which imidization of polyamic acid has been completed on the support substrate is generated when tension is applied to the polyimide film when separating the polyimide film from the support substrate, or when peeling using, for example, a knife edge. The polyimide film is stretched by stress or the like to the polyimide film. Therefore, it becomes easy to generate|occur|produce the dispersion|variation in in-plane retardation (RO) of a polyimide film, and especially, the dispersion|variation in RO becomes remarkable, so that a film width is 490 mm or more polyimide film. The polyimide film of this embodiment makes it easy to form an ordered structure in any of the polyimide constituting the non-thermoplastic polyimide layer and the thermoplastic polyimide layer, thereby dispersing the stress required for peeling to each layer of the polyimide film, thereby reducing RO can be controlled

In addition, in-plane retardation (RO) may be controlled by separating the polyamic acid gel film on the supporting substrate and imidizing the polyamic acid gel film simultaneously or continuously with uniaxial stretching or biaxial stretching. . At this time, in order to control RO more precisely and highly, it is preferable to adjust conditions, such as a temperature increase rate at the time of extending|stretching operation and imidation, completion temperature of imidation, a load, etc. suitably.

(Non-thermoplastic polyimide)

The polyimide film of this embodiment WHEREIN: It is preferable that a non-thermoplastic polyimide contains a tetracarboxylic-acid residue and a diamine residue, these are all aromatic groups, and it is preferable that a biphenyltetrayl group or a biphenylene group is included. Here, the biphenyltetrayl group or the biphenylene group is the same as the diphenyl skeleton, for example, a substituent such as a halogen atom, an alkyl group, an alkoxy group, or an alkenyl group may be bonded to a biphenyltetrayl group or a biphenylene group. From the viewpoint of reducing the amount of change in in-plane retardation (RO) in a high-temperature environment, for example, the number of carbon atoms of a substituent such as an alkyl group, an alkoxy group, or an alkenyl group is more preferably within the range of 1 to 3.

In addition, in this invention, a tetracarboxylic-acid residue shows that it is a tetravalent group derived from tetracarboxylic dianhydride, and a diamine residue shows that it is a divalent group derived from a diamine compound. In addition, although a diamine compound is a compound which has two amino groups, the hydrogen atom in each amino group may be substituted by arbitrary substituents.

Although both the tetracarboxylic acid residue and the diamine residue contained in a non-thermoplastic polyimide are aromatic groups, the change amount of in-plane retardation (RO) in a high temperature environment of a polyimide film can be made small by making it into an aromatic group. In addition, with respect to 100 mol parts in total of the tetracarboxylic acid residue and the diamine residue, preferably the biphenyltetrayl group or the biphenylene group is 40 mol parts or more, more preferably 50 mol parts or more, so that the biphenyltetrayl group or biphenyl group is While making it easy to form the ordered structure by a ren group, and making small the change amount of RO in the high temperature environment of a polyimide film, the dispersion|variation in RO can be suppressed.

In addition, as a tetracarboxylic acid residue contained in a non-thermoplastic polyimide, 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), 2,2',3,3', for example A tetracarboxylic acid residue derived from -biphenyltetracarboxylic dianhydride or the like is preferably exemplified. Among these, a tetracarboxylic acid residue derived from BPDA (hereinafter also referred to as a BPDA residue) is particularly preferable because it tends to form an ordered structure and can reduce the amount of change in in-plane retardation (RO) in a high-temperature environment. In addition, although the BPDA residue can impart self-supporting properties of the gel film as polyamic acid of the polyimide precursor, it tends to increase the CTE after imidization. From this point of view, the BPDA residue is preferably within the range of 20 to 70 mole parts, more preferably within the range of 20 to 60 mole parts with respect to 100 mole parts of all tetracarboxylic acid residues contained in the non-thermoplastic polyimide.

As a tetracarboxylic acid residue other than the said BPDA residue contained in a non-thermoplastic polyimide, the tetracarboxylic-acid residue derived from pyromellitic dianhydride (PMDA) (henceforth a PMDA residue) is illustrated preferably. The PMDA residue is preferably in the range of 0 to 60 mole parts, more preferably in the range of 0 to 50 mole parts, with respect to 100 mole parts of all the tetracarboxylic acid residues contained in the non-thermoplastic polyimide. The PMDA residue is optional, but it is a residue that plays a role in controlling the coefficient of thermal expansion and controlling the glass transition temperature.

Examples of other tetracarboxylic acid residues include 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 2,3',3,4 '-Biphenyltetracarboxylic dianhydride, 2,2',3,3'-, 2,3,3',4'- or 3,3',4,4'-benzophenonetetracarboxylic dianhydride Water, 2,3',3,4'-diphenylethertetracarboxylic dianhydride, bis(2,3-dicarboxyphenyl)ether dianhydride, 3,3'',4,4''-, 2 ,3,3'',4''- or 2,2'',3,3''-p-terphenyltetracarboxylic dianhydride, 2,2-bis(2,3- or 3,4- Dicarboxyphenyl)-propane dianhydride, bis(2,3- or 3,4-dicarboxyphenyl)methane dianhydride, bis(2,3- or 3,4-dicarboxyphenyl)sulfone dianhydride, 1,1 -bis(2,3- or 3,4-dicarboxyphenyl)ethane dianhydride, 1,2,7,8-, 1,2,6,7- or 1,2,9,10-phenanthrene-tetra Carboxylic acid dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)tetrafluoropropane dianhydride, 2,3,5,6 -Cyclohexane dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxyl Acid dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6- or 2,7- Dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-(or 1,4,5,8-)tetrachloronaphthalene-1,4,5,8-( or 2,3,6,7-)tetracarboxylic dianhydride, 2,3,8,9-, 3,4,9,10-, 4,5,10,11- or 5,6,11; 12-perylene-tetracarboxylic dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine -2,3,4,5-tetracarboxylic dianhydride, thiophene-2,3,4,5-tetracarboxylic dianhydride, 4,4'-bis(2,3-dicarboxyphenoxy) Diphenylmethane dianhydride The tetracarboxylic acid residue derived from aromatic tetracarboxylic dianhydride, such as these is illustrated.

In the tetracarboxylic acid residue contained in the non-thermoplastic polyimide, 2,3',3,4'-diphenylethertetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic The tetracarboxylic acid residues derived from the tetracarboxylic dianhydride of acid dianhydride, 4,4'-oxydiphthalic anhydride and 2,3',3,4'-diphenyltetracarboxylic dianhydride are non-thermoplastic. To 100 mol parts of all the tetracarboxylic acid residues contained in a polyimide, Preferably it is 20 mol part or less, More preferably, 15 mol part or less is good. When these tetracarboxylic acid residues exceed 20 mol parts with respect to all the tetracarboxylic acid residues contained in a non-thermoplastic polyimide, the orientation of a molecule|numerator will fall and control of in-plane retardation (RO) becomes difficult.

The polyimide film of this embodiment WHEREIN: As a diamine residue contained in a non-thermoplastic polyimide, the diamine residue represented, for example by following General formula (1) is illustrated preferably.

In the formula (1), R ₁ and R _{2 each} independently represent an alkyl group having 1 to 3 carbon atoms which may be substituted with a halogen atom or a phenyl group, an alkoxy group having 1 to 3 carbon atoms, or an alkenyl group having 2 to 3 carbon atoms. .

The diamine residue represented by General formula (1) tends to form an ordered structure, and can suppress the change amount of in-plane retardation (RO) especially in a high-temperature environment advantageously. From this point of view, the diamine residue represented by the general formula (1) is preferably 20 mole parts or more, more preferably 50 mole parts or more, still more preferably 20 mole parts or more, with respect to 100 mole parts of all the diamine residues contained in the non-thermoplastic polyimide. I like the range of 60-90 molar parts.

Preferred specific examples of the diamine residue represented by the general formula (1) include 2,2'-dimethyl-4,4'-diaminobiphenyl (m-TB), 2,2'-diethyl-4,4'-dia Minobiphenyl (m-EB), 2,2'-diethoxy-4,4'-diaminobiphenyl (m-EOB), 2,2'-dipropoxy-4,4'-diaminobiphenyl (m-POB), 2,2'-n-propyl-4,4'-diaminobiphenyl (m-NPB), 2,2'-divinyl-4,4'-diaminobiphenyl (VAB) and diamine residues derived from diamine compounds such as 4,4'-diaminobiphenyl and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB). Among these, in particular, 2,2'-dimethyl-4,4'-diaminobiphenyl (m-TB) tends to form an ordered structure and can reduce the amount of change in in-plane retardation (RO) in a high-temperature environment. desirable.

As diamine residues other than the diamine residues represented by the general formula (1), diamine residues derived from p-phenylenediamine (p-PDA), m-phenylenediamine (m-PDA), etc. are preferably exemplified, and more Preferably, a diamine residue derived from p-PDA (hereinafter also referred to as a PDA residue) is preferred. The PDA residue is preferably in the range of 0 to 80 parts by mole, more preferably in the range of 0 to 50 parts by mole with respect to 100 parts by mole of all the tetracarboxylic acid residues contained in the non-thermoplastic polyimide. The PDA residue is optional, but it is a residue that plays a role in controlling the coefficient of thermal expansion and controlling the glass transition temperature.

In addition, in order to improve elongation and bending resistance when a polyimide film is used, the non-thermoplastic polyimide is at least one selected from the group consisting of diamine residues represented by the following general formulas (3) to (5). It is preferred to include a diamine residue of

In the formula (3), R ₅ and R ₆ each independently represents a hydrogen atom, or an alkyl group, alkoxy group or alkenyl group which may be substituted with a halogen atom or a halogen atom having 1 to 4 carbon atoms, and X is independently —O -, -S-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -CO-, -COO-, -SO ₂ -, -NH- or -NHCO- The divalent group used is represented, and m and n represent the integers of 1-4 independently.

In the formula (4), R ₅ , R ₆ and R ₇ each independently represents a hydrogen atom, or an alkyl group, alkoxy group or alkenyl group which may be substituted with a halogen atom or a halogen atom having 1 to 4 carbon atoms, and X is independently as -O-, -S-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -CO-, -COO-, -SO ₂ -, -NH- or -NHCO - represents a divalent group selected from, m, n and o independently represent an integer of 1-4.

In the formula (5), R ₅ , R ₆ , R ₇ and R ₈ each independently represent a hydrogen atom or an alkyl group, an alkoxy group or an alkenyl group which may be substituted with a halogen atom or a halogen atom having 1 to 4 carbon atoms, X ₁ and X ₂ are each independently a single bond, -O-, -S-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -CO-, -COO-, -SO ₂ represents a divalent group selected from -, -NH- or -NHCO-, except when both of X ₁ and X ₂ are a single bond, and m, n, o and p are independently 1 Represents an integer of ~4.

Since the diamine residue represented by General formula (3) - General formula (5) has a flexible site|part, it can provide flexibility to a polyimide film. Here, since the diamine residues represented by the general formulas (4) and (5) have three or four benzene rings, in order to suppress an increase in the coefficient of thermal expansion (CTE), the terminal group bonded to the benzene ring is at the para position. it is preferable In addition, from the viewpoint of suppressing an increase in the coefficient of thermal expansion (CTE) while imparting flexibility to the polyimide film, the diamine residues represented by the general formulas (3) to (5) are all diamine residues contained in the non-thermoplastic polyimide. With respect to 100 molar parts of, Preferably it is in the range of 10-40 molar parts, More preferably, it is good in the range of 10-30 molar parts. Elongation at the time of setting it as a film that the diamine residue represented by General formula (3) - General formula (5) is less than 10 mol part will fall, and falls, such as bending resistance, will generate|occur|produce. On the other hand, when it exceeds 40 molar parts, the orientation of a molecule|numerator will fall and it will become difficult to reduce CTE.

In the general formula (3), preferred examples of the groups R ₅ and R ₆ include an alkyl group optionally substituted with a hydrogen atom or a halogen atom having 1 to 4 carbon atoms, or an alkoxy group or alkenyl group having 1 to 3 carbon atoms. Moreover, in General formula (3), as a preferable example of the coupling group X, -O-, -S-, -CH ₂ -, -CH(CH ₃ )-, -SO ₂ -, or -CO- can be illustrated. As a preferable specific example of the diamine residue represented by General formula (3), 4,4'- diaminodiphenyl ether (4,4'-DAPE), 3,3'- diamino diphenyl ether, 3,4'-dia minodiphenyl ether, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 3 , 3'-diaminodiphenylpropane, 3,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 3,4'- Diaminodiphenyl sulfide, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 3 Diamine residues derived from diamine compounds such as ,3'-diaminobenzophenone are exemplified.

In the general formula (4), preferred examples of the groups R ₅ , R ₆ and R ₇ include an alkyl group optionally substituted with a hydrogen atom or a halogen atom having 1 to 4 carbon atoms, an alkoxy group having 1 to 3 carbon atoms or an alkenyl group. can Moreover, as a preferable example of the coupling group X in General formula (4), -O-, -S-, -CH ₂ -, -CH(CH ₃ )-, -SO ₂ -, or -CO- can be illustrated. As a preferable specific example of the diamine residue represented by general formula (4), 1, 3-bis (4-aminophenoxy) benzene (TPE-R), 1, 4-bis (4-aminophenoxy) benzene (TPE-) Q), bis(4-aminophenoxy)-2,5-di-tert-butylbenzene (DTBAB), 4,4-bis(4-aminophenoxy)benzophenone (BAPK), 1,3-bis[ Diamine residues derived from diamine compounds such as 2-(4-aminophenyl)-2-propyl]benzene and 1,4-bis[2-(4-aminophenyl)-2-propyl]benzene are exemplified.

In the general formula (5), preferred examples of the groups R ₅ , R ₆ , R ₇ and R ₈ include an alkyl group optionally substituted with a hydrogen atom or a halogen atom having 1 to 4 carbon atoms, or an alkoxy group or alkenyl group having 1 to 3 carbon atoms. can be exemplified. Moreover, as a preferable example of linking group X ₁ and X ₂ in general formula (5), a single bond, -O-, -S-, -CH ₂ -, -CH(CH ₃ )-, -SO ₂ -, or -CO- can be exemplified. However, from a viewpoint of providing a bending site|part, it shall exclude the case where both coupling groups X ₁ and X ₂ are single bonds. Preferred specific examples of the diamine residue represented by the general formula (5) include 4,4'-bis(4-aminophenoxy)biphenyl (BAPB), 2,2'-bis[4-(4-aminophenoxy)phenyl Derived from diamine compounds such as ]propane (BAPP), 2,2'-bis[4-(4-aminophenoxy)phenyl]ether (BAPE), and bis[4-(4-aminophenoxy)phenyl]sulfone Diamine residues are exemplified.

Examples of other diamine residues include 2,2-bis-[4-(3-aminophenoxy)phenyl]propane, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(3) -Aminophenoxy)biphenyl, bis[1-(3-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(3-aminophenoxy)phenyl] Ether, bis[4-(3-aminophenoxy)benzophenone, 9,9-bis[4-(3-aminophenoxy)phenyl]fluorene, 2,2-bis-[4-(4-aminophenoxy) Si) phenyl] hexafluoropropane, 2,2-bis- [4- (3-aminophenoxy) phenyl] hexafluoropropane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4 ,4'-methylenedi-o-toluidine, 4,4'-methylenedi-2,6-xylidine, 4,4'-methylene-2,6-diethylaniline, 3,3'-diaminodi Phenylethane, 3,3'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 3,3''-diamino-p-terphenyl, 4,4'-[1,4-phenylenebis ( 1-methylethylidene)]bisaniline, 4,4'-[1,3-phenylenebis(1-methylethylidene)]bisaniline, bis(p-aminocyclohexyl)methane, bis(p- β-amino-t-butylphenyl)ether, bis(p-β-methyl-δ-aminopentyl)benzene, p-bis(2-methyl-4-aminopentyl)benzene, p-bis(1,1-dimethyl) -5-Aminopentyl)benzene, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,4-bis(β-amino-t-butyl)toluene, 2,4-diaminotoluene, m- xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine, p-xylylenediamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2, Diamine residues derived from aromatic amine compounds such as 5-diamino-1,3,4-oxadiazole and piperazine are exemplified.

In the non-thermoplastic polyimide, thermal expansion coefficient, storage modulus of elasticity, tensile modulus of elasticity by selecting the types of the tetracarboxylic acid residues and diamine residues, and the molar ratios in the case of applying two or more types of tetracarboxylic acid residues or diamine residues You can control your back. Further, in the case of having a plurality of structural units of polyimide in a non-thermoplastic polyimide, it may exist as a block or may exist randomly, but it is preferable to exist randomly from a viewpoint of suppressing the dispersion|variation in in-plane retardation (RO). .

(thermoplastic polyimide)

The polyimide film of this embodiment WHEREIN: It is preferable that a thermoplastic polyimide contains a tetracarboxylic-acid residue and a diamine residue, these are all aromatic groups, and it is preferable that a biphenyltetrayl group or a biphenylene group is included. Here, in the biphenyltetrayl group or biphenylene group, for example, a substituent such as a halogen atom, an alkyl group, an alkoxy group, or an alkenyl group may be bonded to a biphenyltetrayl group or a biphenylene group, but in particular, in-plane retardation ( From a viewpoint of suppression of the change amount of RO), for example, it is preferable to make carbon number of substituents, such as an alkyl group, an alkoxy group, an alkenyl group, into 1-3 range.

Although both the tetracarboxylic acid residue and the diamine residue contained in a thermoplastic polyimide are aromatic groups, the change amount of in-plane retardation (RO) in the high temperature environment of a polyimide film can be suppressed by setting it as an aromatic group. Moreover, let the biphenyltetrayl group or a biphenylene group be in the range of 30 mol part or more and 80 mol part or less with respect to a total of 100 mol part of a tetracarboxylic-acid residue and a diamine residue. When the biphenyltetrayl group or the biphenylene group is less than 30 mol parts, the formation of an ordered structure by the biphenyltetrayl group or the biphenylene group becomes difficult, and the amount of change in RO in the high-temperature environment of the polyimide film increases. On the other hand, when the biphenyltetrayl group or the biphenylene group exceeds 80 mol parts, the thermoplasticity is impaired.

Further, examples of the tetracarboxylic acid residue contained in the thermoplastic polyimide include BPDA, 2,3',3,4'-biphenyltetracarboxylic dianhydride, and 2,2',3,3'-bi A tetracarboxylic acid residue derived from phenyltetracarboxylic dianhydride or the like is preferably exemplified. Among these, a BPDA residue is particularly preferable because it tends to form an ordered structure and can suppress the amount of change in in-plane retardation (RO) in a high-temperature environment. Therefore, the BPDA residue is preferably 40 mol parts or more, more preferably 50 mol parts or more with respect to 100 mol parts of all tetracarboxylic acid residues contained in the thermoplastic polyimide.

As a tetracarboxylic-acid residue other than the said BPDA residue contained in a thermoplastic polyimide, a PMDA residue is illustrated preferably. The PMDA residue is preferably in the range of 0 to 60 parts by mole, more preferably in the range of 0 to 50 parts by mole with respect to 100 parts by mole of all the tetracarboxylic acid residues contained in the thermoplastic polyimide. The PMDA residue is optional, but it is a residue that plays a role in controlling the coefficient of thermal expansion and controlling the glass transition temperature.

Examples of other tetracarboxylic acid residues include 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 2,2',3,3 '-, 2,3,3',4'- or 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,3',3,4'-diphenylethertetracarboxylic acid dianhydride, bis(2,3-dicarboxyphenyl)ether dianhydride, 3,3'',4,4''-2,3,3'',4''- or 2,2'',3, 3''-p-terphenyltetracarboxylic dianhydride, 2,2-bis(2,3- or 3,4-dicarboxyphenyl)-propane dianhydride, bis(2,3- or 3,4- dicarboxyphenyl)methane dianhydride, bis(2,3- or 3,4-dicarboxyphenyl)sulfone dianhydride, 1,1-bis(2,3- or 3,4-dicarboxyphenyl)ethane dianhydride; 1,2,7,8-, 1,2,6,7- or 1,2,9,10-phenanthrene-tetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride Water, 2,2-bis(3,4-dicarboxyphenyl)tetrafluoropropane dianhydride, 2,3,5,6-cyclohexane dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride Water, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6, 7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6- or 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2, 3,6,7-(or 1,4,5,8-)tetrachloronaphthalene-1,4,5,8-(or 2,3,6,7-)tetracarboxylic dianhydride, 2,3 ,8,9-, 3,4,9,10-, 4,5,10,11- or 5,6,11,12-perylene-tetracarboxylic dianhydride, cyclopentane-1,2,3 ,4-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, thiophene-2 ,3,4,5-tetracarboxylic dianhydride, 4,4'-bis(2,3-dicarboxyphenoxy) diphenylmethane dianhydride, 2,2-bis[4-(3,4-di) Carboxyphenoxy)phenyl]p and tetracarboxylic acid residues derived from aromatic tetracarboxylic acid dianhydrides such as rophan dianhydride.

The polyimide film of this embodiment WHEREIN: As a diamine residue contained in a thermoplastic polyimide, the diamine residue represented, for example by following General formula (2) is illustrated preferably.

In the formula (2), R ₃ and R ₄ independently represent an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or an alkenyl group which may be substituted with a halogen atom or a phenyl group.

The diamine residue represented by the general formula (2) tends to form an ordered structure, and in particular, it is possible to advantageously suppress the change amount of in-plane retardation (RO) in a high-temperature environment. From such a viewpoint, the diamine residue represented by the general formula (2) is preferably within the range of 3 to 60 mole parts, more preferably 5 to 40 mole parts with respect to 100 mole parts of all the diamine residues contained in the thermoplastic polyimide. range i like When the diamine residue represented by the general formula (2) is less than 3 molar parts, the formation of an ordered structure becomes difficult, the amount of change in in-plane retardation (RO) of the polyimide film under a high-temperature environment increases, and when it exceeds 60 molar parts, the thermoplasticity is impaired. .

Preferred specific examples of the diamine residue represented by the general formula (2) include 2,2'-dimethyl-4,4'-diaminobiphenyl (m-TB), 2,2'-diethyl-4,4'-dia Minobiphenyl (m-EB), 2,2'-diethoxy-4,4'-diaminobiphenyl (m-EOB), 2,2'-dipropoxy-4,4'-diaminobiphenyl (m-POB), 2,2'-n-propyl-4,4'-diaminobiphenyl (m-NPB), 2,2'-divinyl-4,4'-diaminobiphenyl (VAB) and diamine residues derived from diamine compounds such as 4,4'-diaminobiphenyl and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB). Among these, 2,2'-dimethyl-4,4'-diaminobiphenyl (m-TB) is particularly preferable because it tends to form an ordered structure and can reduce the amount of change in in-plane retardation (RO) in a high-temperature environment. Do.

Examples of the diamine residue other than the diamine residue represented by the general formula (2) include preferably diamine residues derived from p-phenylenediamine (p-PDA), m-phenylenediamine (m-PDA), etc., more preferably Preferably, a diamine residue derived from p-PDA (hereinafter also referred to as a PDA residue) is preferred. The PDA residue is preferably in the range of 3 to 60 mole parts, more preferably in the range of 5 to 40 mole parts, with respect to 100 mole parts of all the diamine residues contained in the thermoplastic polyimide. Although the PDA residue is arbitrary, since it has a rigid structure, it has an effect|action which gives an ordered structure to the whole polymer.

In addition, in order to improve the flexibility of the polyimide molecular chain and impart thermoplasticity, the thermoplastic polyimide is at least one diamine residue selected from the group consisting of diamine residues represented by the following general formulas (6) to (12). It is preferable to include

In the formulas (6) to (12), R ₉ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and the linking group A is independently -O-, -S-, -CO-, - SO-, -SO ₂ -, -COO, -CH ₂ -, -C(CH ₃ ) ₂ -, -NH- or -CONH- represents a divalent group selected from, n ₁ is independently an integer of 0-4 indicates However, in Formula (8), the thing which overlaps with Formula (7) shall be excluded, and shall exclude the thing which overlaps with Formula (9) in Formula (10). In addition, "independently" means that in one of the above formulas (6) to (12), or in two or more, a plurality of coupling groups A, a plurality of R ₉ , or a plurality of n ₁ may be the same or different. do.

The diamine residues represented by the general formulas (6) to (12) are preferably in the range of 40 to 97 mol parts with respect to 100 mol parts of all the diamine residues contained in the thermoplastic polyimide in total at least one kind. When the total amount of the diamine residues represented by the general formulas (6) to (12) is less than 40 mol parts, thermoplasticity cannot be obtained due to insufficient flexibility of the polyimide, and when it exceeds 97 mol parts, in-plane retardation of the polyimide film under a high-temperature environment The change amount of (RO) tends to increase.

The diamine residue represented by Formula (6) is an aromatic diamine residue which has two benzene rings. The diamine compound that is the source of the diamine residue represented by the formula (6) has at least one amino group directly connected to the benzene ring and the divalent linking group A at the meta position, thereby increasing the degree of freedom of the polyimide molecular chain, and has high flexibility. It is thought to contribute to the improvement of the flexibility of the polyimide molecular chain. Therefore, the thermoplasticity of a polyimide becomes high by using the diamine residue represented by Formula (6). Here, as linking group A, -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -CO-, -SO ₂ -, -S- are preferable.

Examples of the diamine residue represented by the formula (6) include 3,3'-diaminodiphenylmethane, 3,3'-diaminodiphenylpropane, 3,3'-diaminodiphenylsulfide, 3, 3'-diaminodiphenylsulfone, 3,3-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,4'-diaminodiphenylmethane, 3,4'-diaminodiphenyl Diamine residues derived from diamine compounds such as propane, 3,4'-diaminodiphenyl sulfide, 3,3'-diaminobenzophenone and (3,3'-bisamino)diphenylamine can be exemplified. .

The diamine residue represented by Formula (7) is an aromatic diamine residue which has three benzene rings. The diamine compound, which is the source of the diamine residue represented by the formula (7), has an amino group directly connected to at least one benzene ring and a divalent linking group A at the meta position, thereby increasing the degree of freedom of the polyimide molecular chain and has high flexibility It is thought to contribute to the improvement of the flexibility of the polyimide molecular chain. Therefore, the thermoplasticity of a polyimide becomes high by using the diamine residue represented by Formula (7). Here, as the linking group A, -O- is preferable.

Examples of the diamine residue represented by the formula (7) include 1,4-bis(3-aminophenoxy)benzene, 3-[4-(4-aminophenoxy)phenoxy]benzeneamine, 3-[3 -(4-aminophenoxy)phenoxy] The diamine residue derived from diamine compounds, such as benzamine, can be illustrated.

The diamine represented by Formula (8) is an aromatic diamine residue which has three benzene rings. The diamine residue represented by the formula (8) has high flexibility because the degree of freedom of the polyimide molecular chain increases because two divalent linking groups A directly linked to one benzene ring are in meta positions with each other, and the polyimide molecular chain It is thought to contribute to the improvement of the flexibility of Therefore, the thermoplasticity of a polyimide becomes high by using the diamine residue represented by Formula (8). Here, as the linking group A, -O- is preferable.

Examples of the diamine residue represented by the formula (8) include 1,3-bis(4-aminophenoxy)benzene (TPE-R), 1,3-bis(3-aminophenoxy)benzene (APB), 4,4'-[2-methyl-(1,3-phenylene)bisoxy]bisaniline, 4,4'-[4-methyl-(1,3-phenylene)bisoxy]bisaniline, 4, Diamine residues derived from diamine compounds such as 4'-[5-methyl-(1,3-phenylene)bisoxy]bisaniline can be exemplified.

The diamine residue represented by Formula (9) is an aromatic diamine residue which has four benzene rings. The diamine compound as the source of the diamine residue represented by the formula (9) has high flexibility due to the presence of an amino group directly connected to at least one benzene ring and a divalent linking group A in the meta position, and the flexibility of the polyimide molecular chain is improved is thought to contribute to Therefore, the thermoplasticity of a polyimide becomes high by using the diamine residue represented by Formula (9). Here, as linking group A, -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -SO ₂ --CO-, -CONH- are preferable.

Examples of the diamine residue represented by the formula (9) include bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(3-aminophenoxy)phenyl]propane, and bis[4-(3-aminophenoxy). )phenyl]ether, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)benzophenone, bis[4,4'-(3-aminophenoxy)]benz Diamine residues derived from diamine compounds such as anilide can be exemplified.

The diamine residue represented by Formula (10) is an aromatic diamine residue which has four benzene rings. The diamine residue represented by the formula (10) has high flexibility by increasing the degree of freedom of the polyimide molecular chain because two divalent linking groups A directly connected to at least one benzene ring are in meta positions with each other, and the polyimide molecule It is thought that it contributes to the improvement of the flexibility of a chain|strand. Therefore, the thermoplasticity of a polyimide becomes high by using the diamine residue represented by Formula (10). Here, as the linking group A, -O- is preferable.

Examples of the diamine residue represented by formula (10) include 4-[3-[4-(4-aminophenoxy)phenoxy]phenoxy]aniline, 4,4'-[oxybis(3,1-phenyleneoxy) ] A diamine residue derived from a diamine compound such as bisaniline can be exemplified.

The diamine residue represented by Formula (11) is an aromatic diamine residue which has four benzene rings. The diamine residue represented by Formula (11) has high flexibility by having at least two ether bonds, and it is thought that it contributes to the improvement of the softness|flexibility of a polyimide molecular chain. Therefore, the thermoplasticity of a polyimide becomes high by using the diamine residue represented by Formula (11). Here, as the linking group A, -C(CH ₃ ) ₂ -, -O-, -SO ₂ -, or -CO- are preferable.

Examples of the diamine residue represented by the formula (11) include 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP), bis[4-(4-aminophenoxy)phenyl]ether Examples of diamine residues derived from diamine compounds such as (BAPE), bis[4-(4-aminophenoxy)phenyl]sulfone (BAPS), and bis[4-(4-aminophenoxy)phenyl]ketone (BAPK) can do.

The diamine residue represented by Formula (12) is an aromatic diamine residue which has four benzene rings. Since the diamine residue represented by Formula (12) has a highly flexible divalent coupling group A on both sides of a diphenyl backbone, respectively, it is thought that it contributes to the improvement of the flexibility of a polyimide molecular chain. Therefore, the thermoplasticity of a polyimide becomes high by using the diamine residue represented by Formula (12). Here, as the linking group A, -O- is preferable.

Examples of the diamine residue represented by the formula (12) include a diamine residue derived from a diamine compound such as bis[4-(3-aminophenoxy)biphenyl and bis[4-(4-aminophenoxy)biphenyl). can be exemplified.

In the thermoplastic polyimide, thermal expansion coefficient, tensile modulus of elasticity, glass transition temperature You can control your back. Moreover, when it has two or more structural units of polyimide in a thermoplastic polyimide, although it may exist as a block and may exist randomly, it is preferable to exist randomly.

The inside of the range of 10,000-400,000 is preferable, for example, and, as for the weight average molecular weight of a thermoplastic polyimide, the inside of the range of 50,000-350,000 is more preferable. When the weight average molecular weight is less than 10,000, the strength of the film decreases and it tends to become brittle. On the other hand, when the weight average molecular weight exceeds 400,000, the viscosity is excessively increased, and defects such as film thickness non-uniformity and streaks tend to occur during the coating operation.

(Synthesis of non-thermoplastic polyimide and thermoplastic polyimide)

In general, polyimide can be prepared by reacting tetracarboxylic dianhydride with a diamine compound in a solvent to produce polyamic acid, and then heating and ring closure. For example, by dissolving tetracarboxylic dianhydride and a diamine compound in approximately equimolar amounts in an organic solvent and stirring at a temperature within the range of 0 to 100° C. for 30 minutes to 24 hours for polymerization reaction, polyamic acid, a precursor of polyimide, is produced is obtained In the reaction, the reaction component is dissolved so that the precursor to be produced is in the range of 5 to 30% by weight, preferably in the range of 10 to 20% by weight in the organic solvent. Examples of the organic solvent used for the polymerization reaction include N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N,N-diethylacetamide, and N-methyl-2-pi. Rollidone (NMP), 2-butanone, dimethyl sulfoxide (DMSO), hexamethylphosphoamide, N-methylcaprolactam, dimethyl sulfate, cyclohexanone, dioxane, tetrahydrofuran, diglyme, triglyme , cresol and the like are exemplified. Two or more of these solvents can be used in combination, and aromatic hydrocarbons such as xylene and toluene can also be used in combination. In addition, the amount of the organic solvent is not particularly limited, but it is preferable to adjust the amount to be used so that the concentration of the polyamic acid solution obtained by the polymerization reaction is about 5 to 30% by weight.

The synthesized polyamic acid is usually advantageously used as a reaction solvent solution, but may be concentrated, diluted or substituted with other organic solvents if necessary. In addition, polyamic acids are generally used advantageously because of their excellent solvent solubility. The viscosity of the polyamic acid solution is preferably in the range of 500 cps to 100,000 cps. When it deviates from this range, it will become easy to generate|occur|produce defects, such as thickness nonuniformity and a stripe, in a film at the time of a coating operation by a coater etc. The method for imidating the polyamic acid is not particularly limited, and for example, a heat treatment of heating over 1 to 24 hours in the above solvent at a temperature within the range of 80 to 400°C is preferably employed.

<Copper clad laminate>

The copper-clad laminate of the present embodiment includes an insulating layer and a copper layer such as copper foil on at least one surface of the insulating layer, and the insulating layer may be formed using the polyimide film of the present embodiment. Moreover, in order to improve the adhesiveness of an insulating layer and a copper layer, the layer in contact with the copper layer in an insulating layer is a thermoplastic polyimide layer. The copper layer is formed on one side or both sides of the insulating layer. That is, the copper-clad laminate of the present embodiment may be a single-sided copper-clad laminate (single-sided CCL) or a double-sided copper-clad laminate (double-sided CCL). In the case of single-sided CCL, let the copper layer laminated|stacked on the single side|surface of an insulating layer be a "first copper layer" in this invention. In the case of double-sided CCL, the copper layer laminated on one side of the insulating layer is referred to as the "first copper layer" in the present invention, and copper laminated on the surface opposite to the side on which the first copper layer is laminated in the insulating layer. Let the layer be the "second copper layer" in this invention. The copper-clad laminate of this embodiment is used as an FPC by etching a copper layer or processing a wiring circuit to form a copper wiring.

A copper-clad laminate is prepared by preparing a resin film comprising, for example, the polyimide film of the present embodiment, sputtering a metal thereto to form a seed layer, and then forming a copper layer by, for example, copper plating. It can also be prepared.

Moreover, a copper clad laminated board may be prepared by preparing the resin film comprised including the polyimide film of this embodiment, and laminating copper foil to this by methods, such as thermocompression bonding.

Further, the copper-clad laminate may be prepared by casting a coating liquid containing polyamic acid, a precursor of polyimide, on copper foil, drying it to form a coating film, and then heat-treating it to imidize it to form a polyimide layer.

(1st copper layer)

In the copper-clad laminate of the present embodiment, the copper foil used for the first copper layer (hereinafter, may be referred to as "first copper foil") is not particularly limited, and for example, a rolled copper foil may be used and electrolytic Copper foil may be sufficient.

The thickness of 1st copper foil becomes like this. Preferably it is 13 micrometers or less, More preferably, the inside of the range of 6-12 micrometers is good. When the thickness of the first copper foil exceeds 13 μm, the bending stress applied to the copper layer (or copper wiring) when the copper clad laminate (or FPC) is bent increases, so that the bending resistance decreases. Moreover, it is preferable that the lower limit of the thickness of 1st copper foil shall be 6 micrometers from a viewpoint of production stability and handling property.

Moreover, it is preferable to exist in the range of 10-35 GPa, for example, and, as for the tensile modulus of elasticity of 1st copper foil, the range of 15-25 GPa is more preferable. In this embodiment, when using a rolled copper foil as 1st copper foil, if annealed by heat processing, a softness|flexibility will become high easily. Therefore, when the tensile modulus of elasticity of copper foil does not satisfy|fill the said lower limit, the process of forming an insulating layer on elongate 1st copper foil WHEREIN: The rigidity of 1st copper foil itself will fall by heating. On the other hand, when the tensile modulus of elasticity exceeds the upper limit, a large bending stress is applied by the copper wiring when the FPC is bent, and the bending resistance thereof is lowered. Moreover, the tensile modulus of elasticity of a rolled copper foil tends to change with the heat processing conditions at the time of forming an insulating layer on copper foil, annealing process of copper foil after forming an insulating layer, etc. Accordingly, in the present embodiment, in the finally obtained copper clad laminate, the tensile modulus of elasticity of the first copper foil may be within the above range.

The first copper foil is not particularly limited, and a commercially available rolled copper foil can be used.

(second copper layer)

The 2nd copper layer is laminated|stacked on the surface on the opposite side to the 1st copper layer in an insulating layer. It does not specifically limit as copper foil (2nd copper foil) used for a 2nd copper layer, For example, a rolled copper foil may be sufficient and an electrolytic copper foil may be sufficient. Moreover, the copper foil marketed as 2nd copper foil can also be used. Moreover, you may use the thing similar to 1st copper foil as 2nd copper foil.

In the copper-clad laminate of this embodiment, the ratio of the cumulative converted dimensional change to the sum of the wiring width and the wiring spacing of the wiring pattern in the circuit board size (FPC size) of 10 mm obtained by the following evaluation method, the surface of the test piece It is preferable that the deviation within the range is ±2% or less. When the value of this deviation is ±2% or less, it means that both the amount of dimensional change in the longitudinal direction (MD direction) and the amount of dimensional change in the width direction (TD direction) before and after etching are 2% or less. If the value of this deviation exceeds ±2%, it may cause defective connections between wirings or between wirings and terminals in FPC processed from copper clad laminates, thereby reducing reliability and yield of circuit boards. Here, the evaluation method of the dimensional stability of the copper clad laminated board used in this embodiment is demonstrated, referring FIGS. 1-7. This evaluation method is equipped with the following process (1) - process (6).

(1) The process of preparing the test piece:

In this step, as shown in FIG. 1 , a test piece 10 is prepared by cutting a long copper clad laminate 100 to a predetermined length. In the following description, the longitudinal direction of the elongated copper clad laminate 100 is defined as the MD direction and the width direction is defined as the TD direction (the same applies to the test piece 10). It is preferable that the width (length in the TD direction) and the cutting interval (length in the MD direction) of the copper-clad laminate 100 are approximately equal to the test piece 10 to have a shape close to a square. Although not shown, the copper-clad laminate 100 has an insulating resin layer and a copper layer laminated on one side or both sides of the insulating resin layer.

As the copper clad laminate 100 to be subjected to this evaluation method, one prepared by any method may be used. For example, the copper-clad laminate 100 may be prepared by preparing a resin film, sputtering a metal thereon to form a seed layer, and then forming a copper layer by plating. Further, the copper-clad laminate 100 may be prepared by laminating a resin film and copper foil by a method such as thermocompression bonding. Further, the copper-clad laminate 100 may be prepared by coating a resin solution on a copper foil to form an insulating resin layer.

(2) forming a plurality of marks on the test piece:

In this step, as shown in Fig. 2, first, in the test piece 10, an imaginary square 20 having sides parallel to the MD direction and the TD direction (hereinafter, only "square 20" may be described. ) is assumed. The length of one side of the virtual square 20 may be a length corresponding to the width (length in the TD direction) of the copper clad laminate 100 . In addition, since the area of the virtual square 20 is included in the evaluation target up to the limit of the range processed by FPC when a plurality of areas are employed, it is preferable to set the area to cover the range processed by FPC. Therefore, the length of one side of the square 20 is preferably within the range of 60 to 90% of the length of the test piece 10 in the TD direction (the width of the copper clad laminate 100), and is in the range of 70 to 80%. It is more preferable to set it inside. For example, when the width (length in the TD direction) of the copper-clad laminate 100 is 250 mm, the length of one side of the virtual square 20 is preferably set within the range of 150 to 225 mm, and 175 to 200 It is more preferable to set within the range of mm.

Next, as shown in FIGS. 2-4, the center area|region 21 containing the center 20a of the virtual square 20, and the two corners which share one side of the TD direction in the square 20. A plurality of marks each including a linear arrangement are formed in the two corner regions 23a and 23b including one of the portions 20b. The mark is, for example, a round hole 30 penetrating the test piece 10 . The plurality of holes 30 are preferably formed at equal intervals. In addition, the hole 30 as a mark may be polygonal shape, such as a triangle, a rectangle, for example. In addition, the mark is not limited to a through hole as long as the position can be identified, For example, a groove|channel, a notch, etc. may be formed in the test piece 10, and the pattern printed using ink etc. may be sufficient.

<center area>

Since the center 20a of the imaginary square 20 serves as a reference of coordinates for measuring the expansion and contraction of the test piece 10, in this evaluation method, the center area 21 including the center 20a is used as the measurement target. do. In the central region 21, the positions of the plurality of holes 30 are arbitrary as long as they include a linear arrangement, for example, they may be arranged in a T-shape, an L-shape, etc., but the virtual square 20 A cross shape that can be uniformly arranged in the MD direction and the TD direction from the center 20a of the is preferred. That is, as shown in Fig. 3, it is preferable to form the plurality of holes 30 in the MD direction and the TD direction along the cross shape passing through the center 20a of the virtual square 20, and the cross section of the cross shape is It is more preferable to arrange so as to overlap the center 20a of the virtual square 20 . In this case, the holes 30 overlapping the center 20a are counted as overlapping holes 30 constituting the bidirectional arrangement of the MD direction and the TD direction.

In addition, in the central region 21, in order to accurately evaluate dimensional stability including variations in dimensional changes in the plane of the test piece 10, from the center 20a in the square 20 to the MD and TD directions. It is good to form the hole 30 over the length of each side of the square 20 at least 12.5% or more, preferably within the range of 12.5 to 32.5%, more preferably within the range of 12.5 to 25%.

<Corner area>

In the square 20, the periphery of the two corner portions 20b sharing one side in the TD direction is the easiest to expand and contract in the elongated copper clad laminate 100 as shown in FIG. It's an easy area. Therefore, in this evaluation method, both of the two corner areas 23a and 23b including one of the two corner portions 20b sharing one side in the TD direction of the square 20 are the measurement objects. .

In the corner regions 23a and 23b, the positions for forming the holes 30 are arbitrary as long as they include a linear arrangement, but for example, as shown in FIG. 20), it is preferable to form an L-shape in the MD direction and the TD direction along the two sides sandwiching the corner portion 20b. In this case, the holes 30 overlapping the corner portions 20b are counted as overlapping holes 30 constituting the arrangement in both directions in the MD direction and in the TD direction. In addition, although FIG. 4 has shown only the one corner area|region 23b, it is the same also about the other corner area|region 23a.

In the two corner regions 23a and 23b, both ends of one side in the TD direction in the square 20 (that is, the square From the corner portion (20b) of (20)) toward the central side in the MD direction, each is at least 12.5% or more, preferably within the range of 12.5 to 32.5%, more preferably 12.5 to 25% with respect to the length of one side in the MD direction. It is preferable to form the hole 30 over the range of .

In addition, in the two corner regions 23a and 23b, both ends of one side of the TD direction in the square 20 ( That is, from the corner portion 20b of the square 20) toward the center side in the TD direction, at least 12.5% or more, preferably within the range of 12.5 to 32.5%, more preferably 12.5% with respect to the length of one side in the TD direction, respectively. It is preferable to form the hole 30 over the range of ~25%.

In addition, in order to cover the inside of the surface of the test piece 10 and accurately grasp the dimensional change for each site, the arrangement range between the holes 30 at both ends arranged in a straight line in the central area 21, and the corner area In (23a, 23b), the arrangement range between the holes 30 at both ends linearly arranged in the same direction may be overlapped.

Specifically, at least the positions of both ends of the plurality of holes 30 arranged in the MD direction in the central region 21, and the plurality of holes ( 30), you may arrange|position so that the position of the hole 30 of the innermost (the side farthest from the corner part 20b) may overlap when it is made to move in parallel in the TD direction.

Similarly, at least among the plurality of holes 30 arranged in the TD direction within the central region 21 , the position of the hole 30 closest to the corner regions 23a and 23b, and the two corner regions 23a and 23b Among the plurality of holes 30 arranged in the TD direction, the position of the hole 30 of the innermost (the side farthest from the corner portion 20b) may be disposed so as to overlap when moved in parallel in the MD direction.

Considering the arrangement as described above, it is most reasonable to arrange the plurality of holes 30 in a cross shape in the central region 21, and the plurality of holes 30 are L in the two corner regions 23a and 23b. It makes the most sense to arrange them in a shape.

In the imaginary square 20 of the test piece 10, the range for forming the hole 30 is the size of the hole 30, the number of holes 30, and the length of the gap between the hole 30 and the hole 30. can be adjusted by

The size of the hole 30 is preferably within the range of 20% or less of the length of the interval between the hole 30 and the hole 30 in order to increase the detection accuracy of the dimensional change.

The plurality of holes 30 formed in the central region 21 and the two corner regions 23a and 23b are provided in order to accurately evaluate dimensional stability including variations in dimensional changes in the plane of the test piece 10, In each of the MD direction and the TD direction, it is preferable to include at least 11 or more linear arrays, and more preferably include 20 or more linear arrays. Here, if the number of holes 30 is n, the number of intervals between adjacent holes 30 and holes 30 to be measured in subsequent steps (3) and (5) is n-1. . The interval between the adjacent holes 30 and the holes 30 is, for example, 9 places when the number of the holes 30 is 10, and 20 places when the number of the holes 30 is 21, for example. In this case, in the MD direction and the TD direction, the number of holes 30 is preferably the same.

The distance between the hole 30 and the hole 30 is preferably 2 mm or more in order to increase the detection accuracy of the dimensional change.

(3) first measurement step:

In this step, the positions of the plurality of holes 30 are measured. And from the measurement result of the position of each hole 30, the distance L0 between the adjacent hole 30 and the hole 30 is computed. For example, if the number of holes 30 is 21, the distance L0 is calculated|required with respect to the space|interval of 20 places between the adjacent hole 30 and the hole 30. Here, the distance L0 between the adjacent hole 30 and the hole 30 is from the center 30a of the predetermined hole 30 to the center 30a of the adjacent hole 30, as shown in FIG. means distance.

The measurement of the position of the hole 30 is not specifically limited, For example, it can implement by the method of detecting the position of the hole 30 based on the image of the test piece 10. As shown in FIG.

Although the measurement of the position of the hole 30 in this process may be performed continuing to the said process (2), it is preferable to provide the process of adjusting the condition of the test piece 10 before measurement. As an example of condition adjustment of the test piece 10, a humidity control process can be illustrated. A humidity control process can be performed by leaving the test piece 10 still in a fixed environment for a fixed time (for example, 23 degreeC, 24 hours in an environment of 50 RH%).

(4) Etching process:

In this step, part or all of the copper layer of the test piece 10 is etched. In order to evaluate the dimensional stability based on reality, it is preferable that the etching is performed according to the wiring pattern of the FPC formed of the copper clad laminate 100 . When the test piece 10 is prepared from a double-sided copper clad laminate, the copper layers on both sides may be etched. In addition, in actual processing of FPC, when heat processing is involved, you may perform the process of heating the test piece 10 at arbitrary temperature after etching.

(5) second measurement step:

This step is a step of measuring the positions of the plurality of holes 30 again after the etching in (4). And from the measurement result of the position of each hole 30, as shown in FIG. 5, the distance L1 between the adjacent hole 30 and the hole 30 is computed. The position measurement of the hole 30 in this process can be performed by the method similar to the said process (3).

Although the measurement of the position of the hole 30 in this step may be performed continuously in the said process (4), it is preferable to provide the process of adjusting the condition of the test piece 10 similarly to the said process (3). In particular, when conditioning is performed in the step (3), it is preferable to perform the conditioning under the same conditions before measurement in this step as well.

(6) The process of calculating the amount of dimensional change:

In this step, as shown in Fig. 5, the difference L1-L0 between the distance L0 obtained in the first measurement step and the distance L1 obtained in the second measurement step with respect to the interval between the two holes 30 before and after etching is calculated. Calculate. And the difference L1-L0 is similarly computed with respect to 2 or more places, Preferably 10 places or more, and more preferably all, the space|interval of the hole 30 and the hole 30 arranged in the same linear shape. This difference L1-L0 is called "dimensional change amount (Δ)".

(7) The process of converting to wiring scale:

In this step, the amount of dimensional change (Δ) obtained in step (6) is converted into the scale of the wiring pattern in the FPC formed of the copper clad laminate 100, and the converted value is the sum of the wiring width and the wiring spacing of the wiring pattern. expressed as a percentage of By this process, when the copper-clad laminate 100 provided for the test is actually processed into FPC, the effect of the dimensional change of the copper-clad laminate 100 on the wiring pattern of the FPC can be easily expressed.

In this step, first, the amount of dimensional change (Δ) is converted into a scale of wiring width/wiring spacing in the wiring pattern of L/S in the FPC to be formed of the copper clad laminate 100, and the converted amount of dimensional change is accumulated to obtain the cumulative converted dimensional change. For example, with respect to the distance L0 between the two holes 30 before etching, when the wiring width and the wiring interval in the wiring pattern in the FPC to be formed are 1/Y of the distance L0, respectively, the following equation Based on this, the amount of dimensional change (Δ) is converted to the value when downsizing to a scale of 2×(1/Y) to obtain a cumulative conversion amount of dimensional change of a scale of 2×(1/Y).

Cumulative conversion dimensional change = [Σ _{i =1} ⁱ (2×Δ _i /Y)]

In the above formula, the symbol Σ _{i =1} ⁱ represents the total from 1 to i. Further, the dimensional change amount ? is determined from the distance L1 between the n-th hole 30 and the n-1 th hole 30 after etching, the n-th hole 30 and the n-th hole 30 before etching. It represents the value obtained by subtracting the distance L0 of the n-1 th hole 30 (here, n is an integer of 2 or more). For example, Δ ₁ is the amount of dimensional change in the length of the first interval (the distance between two adjacent holes 30), Δ _i is the i-th (i means a positive integer) It is the amount of dimensional change in the length of the gap.

Next, from the accumulated conversion amount of dimensional change, the position shift ratio of the wiring is calculated|required based on the following formula. The displacement ratio of the wiring is expressed as the ratio of the cumulative converted dimensional change to the sum of the wiring width (Lmm) and the wiring spacing (Smm) in the wiring pattern of the L/S to be formed.

Wiring misalignment ratio (%)={[Σ _{i =1} ⁱ (2×Δ _i /Y)/[L+S]}×100

An approximate straight line according to the FPC size is obtained by plotting the displacement ratio of the wirings of MD and TD in the FPC calculated as described above on the graph (in addition, the graph is omitted). Here, the "FPC size" means the distance between the wirings at the farthest ends of the plurality of wirings formed in the FPC. The magnitude of the inclination of the graph means the magnitude of the misalignment of the wiring, and the magnitude of the deviation of the inclination of the graph means the magnitude of the in-plane deviation of the misalignment of the wiring.

By this process, when the copper-clad laminate 100 provided for the test is actually processed into a circuit, the influence of the dimensional change of the copper-clad laminate 100 on the wiring pattern of the FPC can be easily expressed. In addition, by creating a graph of an approximate straight line, it is possible to visualize and express the size of the positional shift and the in-plane deviation of the wiring made of the copper-clad laminate 100 as the test object according to the size of the FPC.

In addition, after accumulating the amount of dimensional change (Δ) obtained in the step (6), the accumulated amount of dimensional change is the wiring width/wiring spacing in the L/S wiring pattern in the FPC to be formed with the copper-clad laminate 100 . It is also possible to convert to the scale of , and obtain the cumulative converted dimensional change. For example, the accumulated dimensional change amount ? is obtained by accumulating the dimensional change amount ? at each interval. This cumulative dimensional change amount Σ can be calculated by the following formula.

Σ=Δ ₁ +Δ ₂ +Δ ₃ +… +Δ _i =Σ _{i = 1} ⁱ Δ _i

The cumulative dimensional change amount Σ can be obtained for either one, preferably both, of the MD direction and the TD direction of the copper-clad laminate 100 . The dimensional stability of the copper-clad laminate 100 in the MD direction and the TD direction can be evaluated depending on the magnitude of the cumulative dimensional change amount Σ. Further, a scaled-up approximate straight line is obtained based on the measured value of the accumulated dimensional change amount Σ.

As described above, according to the present evaluation method, it is possible to evaluate the dimensional change of the copper-clad laminate 100 including in-plane variation with high precision by the steps (1) to (7). In addition, even in the case of employing a plurality of copper clad laminates 100, it becomes possible to individually evaluate the dimensional stability for each processing area to the FPC.

<FPC>

The copper-clad laminate of this embodiment is mainly useful as an FPC material. That is, by processing the copper layer of the copper-clad laminate of this embodiment into a pattern shape by a conventional method to form a wiring layer, the FPC which is an embodiment of the present invention can be manufactured.

[Example]

Hereinafter, an Example is shown and the characteristic of this invention is demonstrated more concretely. However, the scope of the present invention is not limited to the examples. In addition, in the following examples, various measurements and evaluation follow the following unless otherwise indicated.

[Measurement of viscosity]

The measurement of the viscosity measured the viscosity in 25 degreeC using the E-type viscometer (The Brookfield company make, brand name; DV-II+Pro). The rotation speed was set so that a torque might be 10 % - 90 %, and the value when the viscosity stabilized 2 minutes after starting a measurement was read.

[Measurement of Weight Average Molecular Weight]

The weight average molecular weight was measured by gel permeation chromatography (Tosoh Corporation make, brand name; HLC-8220GPC). Polystyrene was used as a standard material, and N,N-dimethylacetamide was used as a developing solvent.

[Measurement of glass transition temperature (Tg)]

The glass transition temperature was a polyimide film having a size of 5 mm × 20 mm, using a dynamic viscoelasticity measuring device (DMA: manufactured by UBM, trade name; E4000F) from 30°C to 400°C at a temperature increase rate of 4°C/min, frequency The measurement was performed at 11 Hz, and the temperature at which the elastic modulus change (tan δ) becomes the maximum was made into the glass transition temperature. In addition, the storage modulus at 30 ° C. measured using DMA is 1.0 x 10 ⁹ Pa or more, and the storage modulus at 360 ° C. is less than 1.0 x 10 ⁸ Pa is referred to as “thermoplastic”, and at 30 ° C. The storage modulus in the case was 1.0×10 ⁹ Pa or more, and the storage modulus at 360°C showing 1.0×10 ⁸ Pa or more was defined as “non-thermoplastic”.

[Measurement of coefficient of thermal expansion (CTE)]

A polyimide film having a size of 3 mm × 20 mm was heated from 30° C. to 265° C. at a constant temperature increase rate while applying a load of 5.0 g using a thermomechanical analyzer (manufactured by Bruker, trade name; 4000SA), and the After holding at the temperature for 10 minutes, it was cooled at a rate of 5°C/min, and the average coefficient of thermal expansion (coefficient of thermal expansion) from 250°C to 100°C was obtained.

[Measurement of surface roughness of copper foil]

The surface roughness of copper foil is AFM (Brooker AXS, brand name: Dimension Icon type SPM), probe (Brooker AXS, brand name: TESPA (NCHV), tip curvature radius 10nm, spring constant 42N/m ) was used to measure the range of 80 µm × 80 µm on the surface of the copper foil in tapping mode, and the ten-point average roughness (Rz) was obtained.

[Measurement of Peel Strength]

1) Cast side of single-sided copper clad laminate (resin coated side)

After circuit processing the copper foil of the single-sided copper clad laminate (copper foil / resin layer) to a width of 1.0 mm, the width; 8cm x length; It cut|disconnected to 4 cm, and the measurement sample 1 was prepared. The peel strength of the cast side of the measurement sample 1 is fixed to the aluminum plate with a double-sided tape by using a tensilon tester (manufactured by Toyo Seiki Seisakusho, trade name; Strograph VE-1D), and the resin layer side of the measurement sample 1 is used, The central strength when 10 mm of copper foil was peeled from the resin layer by the speed|rate of 50 mm/min of copper foil in a 90 degree direction was calculated|required. Let this value be 1A of peeling strength.

2) Cast side of double-sided copper clad laminate (resin coating side)

After performing circuit processing (wiring processing so that the copper foils on both sides are in the same position), the copper foils on both sides of the hot-compression bonding side and the cast side of the double-sided copper clad laminate (copper foil/resin layer/copper foil) are 0.8 mm wide, and then the width; 8cm x length; It cut|disconnected to 4 cm, and the measurement sample 2 was prepared. The peel strength of the cast side of measurement sample 2 was measured by using a tensilon tester (manufactured by Toyo Seiki Seisakusho, trade name; Strograph VE-1D), and the copper foil surface on the thermocompression bonding side of measurement sample 2 was applied to an aluminum plate with double-sided tape. It fixed and the median intensity|strength at the time of 10 mm peeling of copper foil from the copper foil and resin layer by the side of resin coating at a speed|rate of 50 mm/min in a 90 degree direction was calculated|required. Let this value be 2A of peeling strength.

[Measurement of in-plane retardation (RO)]

In-plane retardation (RO) uses a birefringence meter (manufactured by Photonic Latis, trade name; wide-range birefringence evaluation system WPA-100, measurement area; MD: 140 mm x TD: 100 mm) in the in-plane direction of a given sample. Retardation was sought. Incident angle is 0°, and the measurement wavelength is 543 nm.

[Measurement of tensile modulus]

For the tensile modulus of elasticity of copper foil, copper foil subjected to the same heat treatment process as that of copper clad laminate was applied using a vacuum oven, and temperature 23 ° C., relative humidity using a strograph R-1 manufactured by Toyo Seiki Seisakusho Co., Ltd. The value of the tensile modulus of elasticity was measured under an environment of 50%.

The symbol used for the Example and the comparative example shows the following compounds.

NTCDA: 2,3,6,7-naphthalenetetracarboxylic dianhydride

BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride

PMDA: pyromellitic dianhydride

m-TB: 2,2'-dimethyl-4,4'-diaminobiphenyl

m-EOB: 2,2'-diethoxy-4,4'-diaminobiphenyl

TPE-R: 1,3-bis(4-aminophenoxy)benzene

DAPE: 4,4'-diaminodiphenyl ether

BAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]propane

DMAc: N,N-dimethylacetamide

(Synthesis Example 1)

1146.4 parts by weight of m-TB (5.4 mol parts) and 175.4 parts by weight TPE-R (0.6 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight was added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve made it Subsequently, 706.1 parts by weight of BPDA (2.4 mol parts) and 965.4 parts by weight of NTCDA (3.6 mol parts) were added, and then, stirring was continued at room temperature for 3 hours to carry out polymerization reaction to obtain polyamic acid solution 1. The solution viscosity of polyamic acid solution 1 was 41,100 cps.

Next, on the support base material made of stainless steel, after apply|coating the polyamic-acid solution 1 uniformly so that the thickness after hardening might become about 25 micrometers, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120°C to 360°C is performed within 30 minutes, imidization is completed, and polyimide film 1 (biphenyltetrayl group and biphenylene group; 65 mol%, non-thermoplasticity, Tg; 400°C or higher, CTE ; 7.7 ppm/K) was prepared.

(Synthesis Example 2)

743.0 parts by weight of m-TB (3.5 mol parts) and 672.4 parts by weight of TPE-R (2.3 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight was added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve . Subsequently, after adding 353.1 parts by weight of BPDA (1.2 mol parts) and 1233.6 parts by weight of NTCDA (4.6 mol parts), the polymerization reaction was continued at room temperature for 3 hours to obtain a polyamic acid solution 2. The solution viscosity of polyamic acid solution 2 was 41,900 cps.

Next, after apply|coating the polyamic-acid solution 2 uniformly so that the thickness after hardening might be set to about 25 micrometers on the stainless steel support base material, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120° C. to 360° C. within 30 minutes, imidization was completed, and polyimide film 2 (biphenyltetrayl group and biphenylene group; 41 mol%, non-thermoplastic, Tg; 391° C., CTE; 19.1 ppm/K) was prepared.

(Synthesis Example 3)

1040.2 parts by weight of m-TB (4.9 mol parts) and 350.8 parts by weight of TPE-R (1.2 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight was added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve . Next, BPDA (1.8 mol parts), 643.6 parts by weight of NTCDA (2.4 mol parts) and 392.6 parts by weight of PMDA (1.8 mol parts) were added to 529.6 parts by weight, followed by polymerization reaction at room temperature for 3 hours to conduct a polymerization reaction to conduct polyamic acid solution 3 got The solution viscosity of polyamic acid solution 3 was 32,500 cps.

Next, after apply|coating the polyamic acid solution 3 uniformly so that the thickness after hardening might be set to about 25 micrometers on the support base material made of stainless steel, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120°C to 360°C was performed within 30 minutes, imidization was completed, and polyimide film 3 (biphenyltetrayl group and biphenylene group; 55 mol%, non-thermoplastic, Tg; 377°C, CTE; 14.8 ppm/K) was prepared.

(Synthesis Example 4)

552.0 parts by weight of m-TB (2.6 mol parts) and 760.9 parts by weight DAPE (3.8 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight were added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve. Subsequently, after adding 1716.3 parts by weight of NTCDA (6.4 mol parts), stirring was continued at room temperature for 3 hours to carry out polymerization reaction to obtain polyamic acid solution 4. The solution viscosity of polyamic acid solution 4 was 42,300 cps.

Next, after apply|coating the polyamic acid solution 4 uniformly so that the thickness after hardening might be set to about 25 micrometers on the support base material made from stainless steel, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120° C. to 360° C. within 30 minutes, imidization was completed, and polyimide film 4 (biphenylene group; 20 mol%, non-thermoplastic, Tg; 400° C. or higher, CTE; 32.1 ppm/K) ) was prepared.

(Synthesis Example 5)

898.7 parts by weight of m-EOB (3.3 mol parts) and 660.8 parts by weight of DAPE (3.3 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight were added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve. Next, after adding 1439.6 parts by weight of PMDA (6.6 mol parts), stirring was continued at room temperature for 3 hours, polymerization reaction was performed, and the polyamic acid solution 5 was obtained. The solution viscosity of polyamic acid solution 5 was 31,700 cps.

Next, after apply|coating the polyamic acid solution 5 uniformly so that the thickness after hardening might be set to about 25 micrometers on the support base material made of stainless steel, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120°C to 360°C is performed within 30 minutes, imidization is completed, and polyimide film 5 (biphenylene group; 25 mol%, non-thermoplastic, Tg; 376°C, CTE; 33.5 ppm/K) was prepared

(Synthesis Example 6)

63.7 parts by weight of m-TB (0.3 mol parts) and 1490.9 parts by weight of TPE-R (5.1 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight were added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve made it Next, after adding 1118.0 parts by weight of BPDA (3.8 mol parts) and 349.0 parts by weight of PMDA (1.6 mol parts), stirring was continued at room temperature for 3 hours to carry out polymerization reaction to obtain a polyamic acid solution 6. The solution viscosity of the polyamic acid solution 6 was 6,700 cps, and the weight average molecular weight was 163,400.

Next, on the support base material made of stainless steel, after apply|coating the polyamic-acid solution 6 uniformly so that the thickness after hardening might be set to about 25 micrometers, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120°C to 360°C is performed within 30 minutes, imidization is completed, and polyimide film 6 (biphenyltetrayl group and biphenylene group; 38 mol%, thermoplastic, Tg; 242°C, 30°C) Storage modulus: 4.3×10 ⁹ Pa, storage modulus of 360° C.; 1.4×10 ⁷ Pa) was prepared.

(Synthesis Example 7)

743.0 parts by weight of m-TB (3.5 mol parts) and 672.4 parts by weight of TPE-R (2.3 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight was added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve made it Subsequently, after adding 1206.3 parts by weight of BPDA (4.1 mol parts) and 370.8 parts by weight of PMDA (1.7 mol parts), stirring was continued at room temperature for 3 hours to carry out polymerization reaction to obtain a polyamic acid solution 7. The solution viscosity of the polyamic acid solution 7 was 7,200 cps, and the weight average molecular weight was 112,000.

Next, on the support base material made of stainless steel, after apply|coating the polyamic acid solution 7 uniformly so that the thickness after hardening might be set to about 25 micrometers, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120°C to 360°C is performed within 30 minutes, imidization is completed, and polyimide film 7 (biphenyltetrayl group and biphenylene group; 66 mol%, thermoplastic, Tg; 266°C, 30°C) Storage modulus: 4.3×10 ⁹ Pa, storage modulus of 360° C.; 7.1×10 ⁷ Pa) was prepared.

(Synthesis Example 8)

233.5 parts by weight of m-TB (1.1 mol parts) and 1344.7 parts by weight of TPE-R (4.6 mol parts) and DMAc in an amount such that the solid content concentration after polymerization is 15% by weight were added to the reaction tank under a nitrogen stream, and stirred at room temperature to dissolve made it Subsequently, 676.7 parts by weight of BPDA (2.3 mol parts) and 741.6 parts by weight of PMDA (3.4 mol parts) were added, and then, stirring was continued at room temperature for 3 hours to carry out polymerization reaction to obtain a polyamic acid solution 8. The solution viscosity of the polyamic acid solution 8 was 7,400 cps, and the weight average molecular weight was 163,400.

Next, on the support base material made of stainless steel, after apply|coating the polyamic acid solution 8 uniformly so that the thickness after hardening might be set to about 25 micrometers, it heat-dried at 120 degreeC, and the solvent was removed. In addition, stepwise heat treatment from 120°C to 360°C is performed within 30 minutes, imidization is completed, and polyimide film 8 (biphenyltetrayl group and biphenylene group 30 mol%, thermoplastic, Tg; 279°C, 30°C storage) Elastic modulus: 4.1×10 ⁹ Pa, storage modulus of 360° C.; 7.9×10 ⁷ Pa) was prepared.

[Example 1-1]

Continuously in a three-layer structure of the sequence of polyamic acid solution 7/polyamic acid solution 1/polyamic acid solution 7 using a multi-manifold type three-co-extrusion multilayer die on an endless belt-shaped stainless steel support substrate It was applied by extrusion and dried by heating at 130°C for 3 minutes to remove the solvent. Thereafter, stepwise heat treatment is performed from 130°C to 360°C, imidization is completed, and the thickness of the thermoplastic polyimide layer/non-thermoplastic polyimide layer/thermoplastic polyimide layer is 2.5 μm/20 μm/2.5 μm, respectively. Film 1a' was prepared. The polyimide film 1a' on the support base material was peeled by the knife edge method, and the length of the width direction prepared the elongate polyimide film 1a whose length is 1,100 mm.

<Preparation of samples for in-plane retardation (RO) evaluation>

In each of the two left and right ends (Left and Right) and the center part (Center) in the TD direction in the elongate polyimide film 1a, cut to A4 size (TD: 210 mm x MD: 297 mm), sample L1 ( Left), sample R1 (Right), and sample C1 (Center) were prepared.

<Evaluation of in-plane retardation (RO)>

In-plane retardation (RO) was measured for each of Sample L1, Sample R1, and Sample C1, respectively. Let the maximum value of the measured value of each sample be "in-plane retardation (RO)", and the difference between the maximum value and the minimum value in the measured value of in-plane retardation (RO) is "in-plane retardation in the width direction (TD direction)" Variation (ΔRO) of (RO)”. In addition, "the amount of change of in-plane retardation (RO) before and after pressurization in an environment of temperature 360° C., pressure of 340 MPa/m2, and holding time of 15 minutes" is each in-plane retardation before and after pressurization in sample C1 ( It was set as the difference of the maximum value in the measured value of RO).

In addition, the measurement area in each sample is as follows.

Sample L1: Left end region in TD direction and central region in MD direction

Sample R1: right end region in TD direction and central region in MD direction

Sample C1: central region in TD direction and MD direction

The evaluation result of the elongate polyimide film 1a is as follows.

CTE; 17ppm/K

in-plane retardation (RO); 11nm

deviation (ΔRO) of in-plane retardation (RO) in the width direction (TD direction); 1 nm

Change amount of in-plane retardation (RO) before and after pressurization in the environment of temperature 360 degreeC, pressure 340 MPa/m<2>, and holding time 15 minutes; 3nm

[Example 1-2]

Except having made the length of the width direction (TD direction) into 540 mm, it carried out similarly to Example 1-1, and prepared the elongate polyimide film 1b.

The evaluation result of the elongate polyimide film 1b is as follows.

CTE; 17ppm/K

in-plane retardation (RO); 11nm

deviation (ΔRO) of in-plane retardation (RO) in the width direction (TD direction); 1 nm

Change amount of in-plane retardation (RO) before and after pressurization in the environment of temperature 360 degreeC, pressure 340 MPa/m<2>, and holding time 15 minutes; 3nm

[Example 1-3]

Long copper foil 1 (Rolled copper foil, JX Kinzoku Co., Ltd. make, trade name; GHY5-93F-HA-V2 foil, thickness; 12 µm tensile modulus of elasticity after heat treatment; 18 GPa, length in the width direction; 540 mm) The polyamic acid solution 7 was uniformly applied to the surface of the polyamic acid so that the thickness after curing was 2.5 μm, and then the solvent was removed by heating and drying at 120° C. for 1 minute. After that, the polyamic acid solution 1 was uniformly applied to a thickness of 20 µm after curing, and then dried by heating at 120°C for 3 minutes to remove the solvent. Moreover, after apply|coating polyamic acid 7 uniformly so that the thickness after hardening might become 2.5 micrometers on it, it heat-dried at 120 degreeC for 1 minute, and the solvent was removed. Thereafter, stepwise heat treatment was performed from 130°C to 360°C to complete imidization to prepare a single-sided copper-clad laminate 1a.

The evaluation result of the elongate polyimide film prepared by etching-removing the copper foil of the single-sided copper clad laminated board 1a is as follows.

CTE; 17ppm/K

in-plane retardation (RO); 11nm

deviation (ΔRO) of in-plane retardation (RO) in the width direction (TD direction); 1 nm

Copper foil 1 was overlapped on the polyimide layer side of the single-sided copper-clad laminate 1a, and thermocompression-bonded at a temperature of 360° C. and a pressure of 340 MPa/m for 15 minutes to prepare a double-sided copper-clad laminate 1a. The in-plane retardation (RO) of the elongate polyimide film prepared by etching away the copper foil of the double-sided copper clad laminate 1a was 8 nm.

A central portion of the prepared double-sided copper-clad laminate 1a was slitted, and a long copper-clad laminate 1a' (tip width: 250 mm) was prepared as a material for evaluation of dimensional stability.

<Preparation of sample for evaluation of dimensional stability>

The copper-clad laminate 1a' was cut to a length of 250 mm in the MD direction, and MD: 250 mm x TD: 250 mm. As shown in Fig. 6, an imaginary square was assumed in the range of MD: 200 mm x TD: 200 mm in the cut copper-clad laminate. In each of the two left and right corner areas (Left and Right) each including two corner portions sharing one side in the TD direction of this virtual square, and the central area (Center) including the center of the virtual square, In the MD and TD directions, 21 holes were drilled continuously at intervals of 2.5 mm to prepare a sample for evaluation. In addition, a 0.105 mm diameter drill was used for the drilling process.

<Evaluation of dimensional stability>

Using a non-contact CNC image measuring machine (manufactured by Mitutoyo, trade name; Quick Vision QV-X404PIL-C), the positions of each hole before and after etching and removing all of the copper foil layers on both sides in the evaluation sample were measured. From the measured values, the dimensional change amount and the cumulative dimensional change amount of the distance between two adjacent holes before and after etching were calculated.

A long copper-clad laminate 1a' was prepared, and as shown in FIG. 7, samples 1 and 2 for evaluation were prepared. For each of Samples 1 and 2 for evaluation, the positions of each hole before and after etching in Center, Left, and Right were measured. From the measured value, the dimensional change amount of the distance between two adjacent holes before and after etching and the cumulative dimensional change amount of those total (20 places) were computed.

Table 1 shows the cumulative dimensional changes and deviations of MD based on the evaluation results of the copper clad laminate 1a'. In addition, in Table 1, the cumulative dimensional change rate and the cumulative dimensional change amount in Left, Center, and Right are expressed as the cumulative converted dimensional change amount converted to the assumed FPC size of 10 mm, and the deviation in the entire range of Left, Center, and Right is indicating In addition, "cumulative dimensional change rate" means the ratio (%) of the accumulated dimensional change amount with respect to the total value of the distance between two holes before etching. In addition, the numerical value of "range" in the table means the median value ± the upper and lower ranges in the entire range of Left, Center, and Right (the same in Tables 2 and 3).

From this result, for a circuit wiring board (L/S = 0.025 mm/0.0025 mm) formed with copper clad laminate 1a' as a material, it is possible to evaluate the deviation of the misalignment ratio of wiring and the rate of dimensional change in the plane of the test piece. While confirming that, it was possible to confirm that the variation in the misalignment ratio of wirings in each FPC size in the double-sided copper-clad laminate 1a of Example 1-3 was small. In addition, it was confirmed that the control of in-plane retardation is important in order to realize high dimensional stability precision of the copper clad laminate, which could not be achieved only by controlling the CTE of the polyimide film.

[Example 1-4]

Copper foil 1 was polymerized on both sides of the long polyimide film 1b prepared in Example 1-2, and thermocompression-bonded at a temperature of 360° C. and a pressure of 340 MPa/m for 15 minutes to prepare a double-sided copper-clad laminate 1b, Example It carried out similarly to 1-3, the elongate copper clad laminated board 1b' (tip width; 250 mm) was prepared, and dimensional stability was evaluated. The results are shown in Table 2.

[Comparative Example 1-1]

An elongated polyimide film 1c (thickness; 25 µm, manufactured by Kaneka Corporation, trade name; Pixio) was prepared.

The evaluation result of the elongate polyimide film 1c is as follows.

CTE; 17ppm/K

in-plane retardation (RO); 200nm

deviation (ΔRO) of in-plane retardation (RO) in the width direction (TD direction); 80nm

Change amount of in-plane retardation (RO) before and after pressurization in the environment of temperature 360 degreeC, pressure 340 MPa/m<2>, and holding time 15 minutes; 30nm

[Comparative Example 1-2]

Copper foil 1 was overlapped on both sides of the elongated polyimide film 1c, and thermocompression-bonded at a temperature of 360° C. and a pressure of 340 MPa/m for 15 minutes to prepare a double-sided copper-clad laminate 1c, in the same manner as in Example 1-3. A copper clad laminate 1c' (tip width; 250 mm) was prepared, and dimensional stability was evaluated. The results are shown in Table 3.

[Example 2-1]

A long polyimide film 2 having a length of 1,100 mm in the width direction was prepared in the same manner as in Example 1-1 except for the three-layer structure in the order of polyamic acid solution 8/polyamic acid solution 1/polyamic acid solution 8. .

The evaluation result of the elongate polyimide film 2 is as follows.

CTE; 17ppm/K

in-plane retardation (RO); 11nm

deviation (ΔRO) of in-plane retardation (RO) in the width direction (TD direction); 1 nm

Change amount of in-plane retardation (RO) before and after pressurization in the environment of temperature 360 degreeC, pressure 340 MPa/m<2>, and holding time 15 minutes; 5nm

[Example 3-1]

A long polyimide film 3 having a length of 1,100 mm in the width direction was prepared in the same manner as in Example 1-1 except for the three-layer structure in the order of polyamic acid solution 6/polyamic acid solution 2/polyamic acid solution 6. .

The evaluation result of the elongate polyimide film 3 is as follows.

CTE; 17ppm/K

in-plane retardation (RO); 17nm

deviation (ΔRO) of in-plane retardation (RO) in the width direction (TD direction); 3nm

Change amount of in-plane retardation (RO) before and after pressurization in the environment of temperature 360 degreeC, pressure 340 MPa/m<2>, and holding time 15 minutes; 7nm

[Example 4-1]

A long polyimide film 4 having a length of 1,100 mm in the width direction was prepared in the same manner as in Example 1-1 except for the three-layer structure in the order of polyamic acid solution 8/polyamic acid solution 3/polyamic acid solution 8. .

The evaluation result of the elongate polyimide film 4 is as follows.

CTE; 17ppm/K

in-plane retardation (RO); 15nm

deviation (ΔRO) of in-plane retardation (RO) in the width direction (TD direction); 2nm

Change amount of in-plane retardation (RO) before and after pressurization in the environment of temperature 360 degreeC, pressure 340 MPa/m<2>, and holding time 15 minutes; 10nm

As mentioned above, although embodiment of this invention was described in detail for the purpose of illustration, this invention is not restrict|limited to the said embodiment, and various deformation|transformation is possible.

This application claims the priority based on Japanese Patent Application No. 2016-89514 for which it applied on April 27, 2016, The whole content of the said application is used here.

10… Test piece 20... virtual square
20a… Center 20b… corner
21… central regions 23a, 23b... corner area
30… hole 100... Copper clad laminate

Claims (10)

A long polyimide film having a thermoplastic polyimide layer made of a thermoplastic polyimide on at least one of a non-thermoplastic polyimide layer made of a non-thermoplastic polyimide,
20 mol parts or more 70 of tetracarboxylic acid residues derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride with respect to 100 mol parts of all tetracarboxylic acid residues contained in the non-thermoplastic polyimide within the range of less than or equal to molar parts,
While film width exists in the range of 490 mm or more and 1100 mm or less,
The following conditions (i) to (iv);
(i) the coefficient of thermal expansion is within the range of 10 ~ 30ppm / K;
(ii) the glass transition temperature of the thermoplastic polyimide is in the range of 200 °C or more and 350 °C or less;
(iii) the value of in-plane retardation (RO) exists in the range of 5 nm or more and 50 nm or less;
(iv) A polyimide film characterized in that it satisfies that the deviation (ΔRO) of the in-plane retardation (RO) in the width direction (TD direction) is 10 nm or less. The method of claim 1,
In addition to the conditions of (i) to (iv) above,
(v) The polyimide film characterized in that it further satisfies that the amount of change in in-plane retardation (RO) before and after pressurization at a pressure of 340 MPa/m 2 and a holding time of 15 minutes is 20 nm or less in an environment of a temperature of 360°C. 3. The method of claim 1 or 2,
In addition to the conditions of (i) to (iv) above,
(vi) the non-thermoplastic polyimide includes a tetracarboxylic acid residue and a diamine residue, the tetracarboxylic acid residue and the diamine residue are both aromatic groups, and the aromatic group includes a biphenyltetrayl group or a biphenylene group and 40 mol parts or more of the biphenyltetrayl group or the biphenylene group with respect to 100 mol parts in total of the tetracarboxylic acid residue and the diamine residue. 3. The method of claim 1 or 2,
In addition to the conditions of (i) to (iv) above,
(vii) the thermoplastic polyimide includes a tetracarboxylic acid residue and a diamine residue, the tetracarboxylic acid residue and the diamine residue are both aromatic groups, and the aromatic group includes a biphenyltetrayl group or a biphenylene group; , wherein the biphenyltetrayl group or the biphenylene group is in the range of 30 mol parts or more and 80 mol parts or less with respect to 100 mol parts in total of the tetracarboxylic acid residue and the diamine residue. delete 3. The method of claim 1 or 2,
It is characterized in that the amount of tetracarboxylic acid residues derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride is 40 mole parts or more with respect to 100 mole parts of the total tetracarboxylic acid residues contained in the thermoplastic polyimide. A polyimide film made of 3. The method of claim 1 or 2,
The polyimide film characterized in that the diamine residue represented by the following general formula (1) is 20 mole parts or more with respect to 100 mole parts of all the diamine residues contained in the non-thermoplastic polyimide.

[Wherein, R ₁ and R ₂ independently represent an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or an alkenyl group having 2 to 3 carbon atoms which may be substituted with a halogen atom or a phenyl group.] 3. The method of claim 1 or 2,
The polyimide film characterized in that the diamine residue represented by the following general formula (2) is in the range of 3 mole parts or more and 60 mole parts or less with respect to 100 mole parts of all the diamine residues contained in the thermoplastic polyimide.

[Wherein, R ₃ and R ₄ independently represent an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or an alkenyl group which may be substituted with a halogen atom or a phenyl group.] A copper-clad laminate comprising an insulating layer and a copper layer on at least one surface of the insulating layer,
The insulating layer has a thermoplastic polyimide layer in contact with the surface of the copper layer, and a non-thermoplastic polyimide layer indirectly laminated,
A copper-clad laminate, characterized in that the insulating layer is made of the polyimide film according to claim 1 or 2. 10. The method of claim 9,
A copper-clad laminate, wherein both the amount of dimensional change in the longitudinal direction (MD direction) and the amount of dimensional change in the width direction (TD direction) before and after etching the copper layer are 2% or less.

Images