JP2002332407A - Aromatic polysulfone resin solution, film using the same and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aromatic polysulfone resin solution composition having excellent solution stability without causing gelation. SOLUTION: [1] This aromatic polysulfone resin solution composition comprises (A) an aromatic polysulfone resin, (B) an amide solvent and (C) at least one solvent selected from hydrocarbons, ethers and acetals and the contents of (A) is 10-50 wt.% and the weight ratio (B)/(C) is 1.0<=B/C<=25. [2] The aromatic polysulfone resin solution comprises (A) the aromatic polysulfone resin, (B) the amide solvent and (D) the solvent selected from ketones and esters and the contents of (A) is 10-50 wt.% and the weight ratio (B)/(D) is 2<=B/D<=25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an aromatic polysulfone resin solution composition, a film obtained by using the solution composition, and a method for producing the same.

[0002]

2. Description of the Related Art Aromatic polysulfone resin films are excellent in various properties such as mechanical strength, electrical properties, transparency, heat resistance, chemical resistance, and flame retardancy. And retardation films. The aromatic polysulfone resin film can be produced by a casting method. The method disclosed in the following patent publication is known. JP-A-7-24858 discloses a method for producing a polysulfone resin film from an acetophenone solution or an N-methylpyrrolidone solution of a polysulfone resin by a solution casting method. JP-A-7-300559 discloses a method for producing a cast film of aromatic polyethersulfone having excellent surface properties, transparency, and homogeneity by using 1,3-dioxolan. I have. When producing an aromatic polysulfone resin film by a casting method, if the viscosity of the aromatic polysulfone resin solution for casting is low, an orange peel caused by convection on a film in a wet state in an initial state of drying is generated. And the surface smoothness is reduced. In order to solve this problem, it is necessary to increase the viscosity of the aromatic polysulfone resin solution and increase the viscosity.However, when the viscosity is increased, gelation occurs and the storage stability of the aromatic polysulfone resin solution decreases. there were.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an aromatic polysulfone resin solution composition which does not cause gelation and has excellent solution stability.

[0004]

The present inventors have conducted intensive studies to find an aromatic polysulfone resin solution composition which does not have the above-mentioned problems. As a result, the poor solvent of the aromatic polysulfone resin was added to the amide solvent. Alternatively, they have found that a composition in which a specific solvent selected from non-solvents is blended in a specific amount has excellent solution stability without generation of a gelling component, and has completed the present invention.

That is, the present invention provides the following [1] to
This is related to [4]. [1] An aromatic polysulfone resin solution composition containing an aromatic polysulfone resin (A), an amide solvent (B), at least one solvent (C) selected from hydrocarbons, ethers, and acetals. The content of (A) is 10% by weight to 50% by weight, and the weight ratio (B) / (C) of (B) and (C) is 1.0 ≦ B / C ≦ 25. An aromatic polysulfone resin solution composition, comprising: [2] Aromatic polysulfone resin (A), amide solvent (B), solvent (D) selected from ketones and esters
An aromatic polysulfone resin solution composition comprising: (A) having a content of 10% by weight to 50% by weight, and a weight ratio (B) / (D) of (B) and (D). ) Is 2 ≦
An aromatic polysulfone resin solution composition, wherein B / D ≦ 25. [3] An aromatic polysulfone resin film obtained using the solution composition according to [1] or [2]. [4] The method for producing the aromatic polysulfone resin film according to the above [3].

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The aromatic polysulfone resin used in the present invention is a resin containing a repeating structural unit represented by the following general formula (I). Further, the aromatic polysulfone resin may be a resin containing at least one of a structure represented by the following general formula (II) or a structure represented by the following general formula (III); It may be a random copolymer or an alternating copolymer containing a repeating structural unit represented by the formula (III).

[0007] (I) (In the formula (I), R ₁ represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a phenyl group or a halogen atom, and p is an integer of 0 to 4) Each R ₁ on the same or different nuclei may be different from each other, and each p may be different from each other.)

[0008] (II) (wherein, R ₁ represents the same as described above, p is an integer of 0 to 4. m and n each represent an average number of repeating structural units;
m and n are positive numbers from 0.1 to 100. Each R ₁ on the same or different nuclei may be different from each other. Each p may be different from each other. X has 1 to 20 carbon atoms
Represents an organic group, a carbonyl group, a divalent sulfur atom or a divalent oxygen atom. )

[0009] (III) (wherein, R ₁ represents the same as above, p is an integer of 0 to 4. q is an integer of 1 to 5. m and n indicate the average number of repeating structural units.) , M, and n are positive numbers from 0.1 to 100. Each R ₁ on the same or different nucleus may be different from each other, each p may be different from each other, and each q may be different from each other May be.)

Here, examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a t-butyl group and a cyclohexyl group. In addition, carbon number 2-10
Examples of the alkenyl group include, for example, ethynyl group, iso
-Propenyl group and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. As the organic group having 1 to 20 carbon atoms,
Examples thereof include a saturated aliphatic alkylene group such as an isopropylidene group, an ethylidene group, and a methylene group, an unsaturated aliphatic alkylene group such as an ethynylene group, and an aromatic alkylene group such as a xylylene group and a phenylmethylene group.

When the aromatic polysulfone resin used in the present invention contains a structure represented by (II) or (III), (m / m + n) is preferably 0.5 or more, More preferably, it is 8 or more. Also, (II
Q in the structure of I) is preferably 1 or 2,
More preferably, it is 2.

In the present invention, a resin having a structure comprising a repeating structural unit represented by (I) and a resin having a structure represented by (II) are preferably used, and more preferably a resin having a repeating structure represented by (I). A resin containing a unit structure is used. Above all, those in which all p's are 0, that is, a resin containing a structure composed of a repeating structural unit represented by the following formula is more preferable, and contains 80 mol% or more of the repeating structural unit represented by the following formula per one molecular chain. Resins are particularly preferred.

The aromatic polysulfone resin used in the present invention preferably has a reduced viscosity of 0.60 to 1.0 dl / g, more preferably 0.60 to 0.90.
dl / g, and more preferably 0.70 to 0.80.
dl / g. If the resin is less than 0.60 dl / g, it tends to be difficult to obtain a stable aromatic polysulfone resin solution composition suitable for casting, and if it exceeds 1.0 dl / g, a uniform solution is prepared. It ’s difficult,
Filtration and defoaming are difficult, and the appearance of the film tends to be problematic. Here, the reduced viscosity is 100 cm ³ of N,
1 aromatic polysulfone in N-dimethylformamide
g, and the viscosity of this solution was measured at 25 ° C. using an Ostwald viscometer.

As a method for producing the aromatic polysulfone resin, a known method can be employed. Further, a commercially available aromatic polysulfone resin may be used as it is. As commercially available aromatic polysulfone resins, for example,
SUMIKA EXCEL PES7 (trade name) of Sumitomo Chemical Co., Ltd.
Those comprising the above structural unit (I) such as 600P, AM
Examples include those composed of the above structural units (I) and (II) such as UCOLP-1700 (trade name of OCO).
The terminal structure is determined according to the method for producing each resin, and is not particularly limited. For example, -Cl,
—OH, —OR (R is an alkyl group) and the like.

Next, the solvent used in the present invention will be described. The amide solvent (B) is a good solvent for the aromatic polysulfone resin. Examples of the amide solvent (B) include N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethyl. Acetamide and the like can be mentioned, and N, N-dimethylformamide is preferably used. These solvents may be used alone or in combination of two or more. In addition, the amide solvents include:
Sulfoxides such as dimethyl sulfoxide; phenols such as cresol; halogenated carbons such as methylene chloride; esters such as γ-butyrolactone may be added for use.

The solvent (C) selected from hydrocarbons, ethers and acetals, and the solvent (D) selected from ketones and esters are poor solvents or non-solvents for aromatic polysulfone resins. By adding a solvent or a non-solvent, the storage stability of the solution composition of the aromatic polysulfone resin can be further improved, and the solution viscosity at the same concentration decreases as compared with the case where a good solvent is used alone. Therefore, high solid differentiation can be achieved, which is very advantageous in practical use.

Examples of the hydrocarbons include hexane,
2-methylpentane, 2,2-dimethylbutane, 2,3
-Dibutylbutane, heptane, octane, benzene, toluene, xylene, ethylbenzene, cumene, cyclohexane, methylcyclohexane, ethylcyclohexane, cyclohexene, etc., of which cyclohexane and toluene are preferred, and toluene is more preferred.

Examples of ether / acetals include petroleum ether, diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, dihexyl ether, ethyl vinyl ether, butyl vinyl ether, anisole, phenetole, butyl phenyl ether, pentyl phenyl ether, methoxy Toluene, benzyl ethyl ether, diphenyl ether,
Dibenzyl ether, veratol, propylene oxide, 1,2-epoxybutane, dioxane, trioxane, furan, 2-methylfuran, tetrahydrofuran,
Tetrahydropyran, zioner, 1,2-dimethoxyethane, 1,2-diethoxyethane, 1,2-, dibutoxyethane, diethylene glycol dimethyl ether,
Examples thereof include diethylene glycol diethyl ether, diethylene glycol dibutyl ether, glycerin ether, methylal, and acetal. Of these, methylal is preferred.

Examples of the ketones include acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, isophorone, camphor and the like. Of these, acetone and cyclopentanone are preferred. , Acetone is more preferred. Examples of the esters include methyl formate, ethyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, and the like. Of these, ethyl acetate is preferred.

The weight ratio of the amide solvent (B) to the solvent (C) selected from hydrocarbons and ethers / acetals (B /
C) is 0.8 ≦ B / C ≦ 25, preferably 1.0
≦ B / C ≦ 19, more preferably 1.5 ≦ B / C ≦ 10. When the weight ratio (B / C) is less than 0.8, the solution stability and the solubility of the aromatic polysulfone resin are significantly reduced. Also,
If the weight ratio (B / C) exceeds 25, it is difficult to increase the drying speed.

The weight ratio (B / D) of the solvent (D) selected from ketones and esters is 2.0 ≦ B / D ≦ 25, preferably 3 ≦ B / D ≦ 19. Preferably 3 ≦
B / D ≦ 10. When the weight ratio (B / D) is less than 2.0, the solution stability and the solubility of the aromatic polysulfone resin are significantly reduced. If the weight ratio (B / D) exceeds 25, it is difficult to increase the drying speed.

The concentration of the aromatic polysulfone resin (A) in the solution composition of the present invention is from 10% by weight to 50% by weight, preferably from 20% by weight to 40% by weight.
When the concentration is less than 10% by weight, since the effective concentration is low, an orange peel due to convection occurs in the film particularly at an early stage of drying, particularly in a thick film, and the surface smoothness is reduced.
On the other hand, if it exceeds 50% by weight, the solution composition may gel during storage due to crystallization of the aromatic polysulfone resin and the like, resulting in inferior stability. Poor sex.

The method for producing the solution is not particularly limited.
The solvent may be added to the resin, or the resin may be added to the solvent. In order to increase the dissolution rate, it is preferable to use a powder as the form of the resin, but there is no particular limitation.

The solution of the present invention may contain various additives such as a leveling agent and a plasticizer, if necessary. As the leveling agent, acryl-based, silicone-based, and fluorine-based agents can be used. As a plasticizer,
Those which have good compatibility with the aromatic polysulfone resin, do not cause phase separation or bleed-out, and do not cause coloring are preferred. For example, phthalic acid-based, phosphoric acid-based, adipic acid-based, citric acid-based, and glycolic acid-based plasticizers are exemplified, and butylbenzyl phthalate, tricresyl phosphate, and methylphthalylethyl glycolate are preferably used.

The aromatic polysulfone resin film of the present invention and a method for producing the same will be described. The film is
(1) The aromatic polysulfone resin solution composition of the present invention is cast on a support to form a casting film containing a solvent (hereinafter sometimes referred to as a casting step), and then (2) the casting film By evaporating the solvent (hereinafter sometimes referred to as a drying step).

The casting step is a step of forming a casting film containing a solvent on a support. In this step, the aromatic polysulfone resin composition solution of the present invention is a comma coater,
It is common to use a lip coater, a doctor blade coater, a bar coater, a roll coater, or the like to cast the film on a support such as an endless band or a drum. It is preferable that a metal such as stainless steel subjected to mirror finishing, a resin film such as polyethylene terephthalate, glass or the like be used for the support, but it is not particularly limited.

The drying step is a step of evaporating the solvent from the cast film to form an aromatic polysulfone resin film. The solvent is preferably evaporated by heating in order to improve the efficiency of the evaporation. The heating may be performed at a constant temperature, but it is preferable to change the heating over several stages from the viewpoint of economy and smoothness of the film surface.

The amount of the residual solvent in the dried aromatic polysulfone resin film is preferably 5% by weight or less, more preferably 1% by weight or less, further preferably 0.5% by weight or less. When the amount of the residual solvent is large, not only the glass transition temperature (Tg) of the aromatic polysulfone resin film is remarkably lowered, but when heat is applied in post-processing, dimensional change, curl, and moisture absorption tend to be caused. In addition, residual solvents also tend to adversely affect peripheral parts of the film in practical use.

In the production method of the present invention, in order to efficiently produce an aromatic polysulfone resin film having a Tg substantially equivalent to the Tg of the aromatic polysulfone resin as a raw material, the aromatic polysulfone resin must have a Tg or more. It is preferable to include a step of heating at a temperature of

The formed aromatic polysulfone resin film is usually used after being peeled off from the support. The method of peeling is not particularly limited, but a long aromatic polysulfone resin film can be obtained by continuously peeling the film from the support. In addition, a short aromatic polysulfone resin film can be obtained by a batch method using a sheet-like support.

The aromatic polysulfone resin film manufactured in this manner is used, for example, in the field of electric insulation, H-class electric equipment, motor and generator slot liners,
It can be used for insulating materials such as interphase insulation, wrapping materials for transformers and electric wires coated with adhesives and adhesives and processed into tapes, dielectric films such as capacitors, and tube-shaped insulating materials. In the electronics-related field, it can be used for flexible printed circuit boards and their reinforcing plates, heat-resistant spacers, PCB laminates, and the like. In the acoustic-related field, it can be used for diaphragms and vibration reinforcing plates of speakers. In the information-related field, it can be used for recording tapes, disks, and glass substrate replacement films for liquid crystal displays that require dimensional stability, as well as for connection parts of retardation films and optical fibers by being stretched. In the food and medical fields,
It can be used for medical sterilization equipment and heating packs for microwave ovens and microwave ovens.

[0032]

EXAMPLES Next, the present invention will be described based on examples, but it goes without saying that the present invention is not limited by the examples. Note that the aromatic polysulfone resin, Sumika Excel PES7600P, used in the examples substantially consists of the following repeating structural units.

[Viscosity measurement] TV-2 manufactured by Tokimec Co., Ltd.
It measured at room temperature (25 degreeC) using the 0 type viscometer. still,
The measurement was performed at 6 (rpm). [Film thickness measurement] The film thickness was measured using a foil thickness gauge model 497 manufactured by Ericssen. [Measurement of Glass Transition Temperature] Using a thermal analysis system SSC / 5200 manufactured by Seiko Instruments Inc.
/ Min) at 25 ° C to 300 ° C.

Example 1 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and toluene were mixed at a weight ratio of 6: 4 to prepare a solution having a solid content of 20%. When the viscosity of this solution was measured, it was 2.47 (Pa · s). When this solution was left at 25 ° C., no sign of gelation was observed for one month or more. By adding toluene in this way, the solution viscosity was reduced and the stability was improved.

Example 2 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and toluene were mixed at a weight ratio of 6: 4 to prepare a solution having a solid concentration of 27%. When the viscosity of this solution was measured, it was 15.1 (Pa · s). When this solution was left at 25 ° C., no sign of gelation was observed for one month or more. By adding toluene in this way, the solid content concentration could be increased without significantly increasing the solution viscosity.

Example 3 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and methylal were mixed at a weight ratio of 6: 4 to prepare a solution having a solid content of 20%. When the viscosity of this solution was measured, it was 3.06 (Pa · s). Thus, by adding methylal, the solution viscosity could be reduced.

Example 4 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and methylal were mixed at a weight ratio of 6: 4 to prepare a solution having a solid concentration of 25%. When the viscosity of this solution was measured, it was 13.1 (Pa · s). By adding methylal in this way, the solid content concentration could be increased without significantly increasing the solution viscosity.

Example 5 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and ethyl acetate were mixed at a weight ratio of 8: 2 to prepare a solution having a solid content of 20%. When the viscosity of this solution was measured, it was 3.82 (Pa · s). By adding ethyl acetate in this way, the solution viscosity could be reduced.

Example 6 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and acetone were mixed at a weight ratio of 8: 2 to prepare a solution having a solid concentration of 20%. When the viscosity of this solution was measured, it was 3.60 (Pa · s). By adding acetone in this way, the solution viscosity could be reduced.

Example 7 The solution composition described in Example 2 was cast on a glass plate using an applicator having a clearance of 500 μm (manufactured by Tester Sangyo, variable clearance). This glass plate was dried under the conditions shown in Table 3 using a hot plate (pre-drying) and a ventilation oven (post-drying). The total drying time is 5
This was a time, and the drying time could be significantly reduced as compared with the case where toluene was not added. As a result, a favorable film having a thickness of 48 μm and a glass transition temperature (Tg) of 223 ° C. was obtained.

Comparative Example 1 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in N, N-dimethylformamide to prepare a solution having a solid content of 20%. When the viscosity of this solution was measured, it was 10.2 (Pa · s). Also,
When this solution was left at 25 ° C., it gelled in 20 days.

Comparative Example 2 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and toluene were mixed at a weight ratio of 4: 6, and an attempt was made to prepare a solution having a solid concentration of 20%. However, this solution was cloudy and was not suitable for a solution composition for casting.

Comparative Example 3 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and methylal were mixed at a weight ratio of 4: 6, and an attempt was made to prepare a solution having a solid concentration of 20%. However,
PES did not dissolve in this solvent composition.

Comparative Example 4 Trade name: Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and ethyl acetate were mixed at a weight ratio of 6: 4 to prepare a solution having a solid content of 20%. However,
This solution was cloudy and was not suitable for a solution composition for casting.

Comparative Example 5 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in a solvent in which N, N-dimethylformamide and acetone were mixed at a weight ratio of 6: 4, and an attempt was made to prepare a solution having a solid content of 20%. However, this solution gelled and was not suitable for a solution composition for casting.

Comparative Example 6 Sumika Excel PES7600P (manufactured by Sumitomo Chemical Co., Ltd., polyether sulfone, reduced viscosity 0.76d)
1 / g) was dissolved in N, N-dimethylformamide to prepare a solution having a solid content of 20%. This solution composition was cast on a glass plate using an applicator having a clearance of 500 μm (manufactured by Tester Sangyo, variable clearance). This glass plate was dried under the conditions shown in Table 3 using a hot plate (pre-drying) and a ventilation oven (post-drying). Film thickness 53 μm, glass transition temperature (Tg) 220 ° C.
The total drying time required to obtain a film of
5 minutes.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

[Table 3]

[0050]

According to the present invention, it is possible to provide an aromatic polysulfone resin solution composition which does not cause gelation and has excellent solution stability.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F071 AA64 AA88 AC02 AC07 AC10 AC12 AE19 AG36 BA02 BB02 BC01 4J002 CN031 EA036 EE016 EE036 EH036 EP016 FD206 GQ00 HA05

Claims (11)

[Claims] 1. An aromatic polysulfone resin solution composition comprising an aromatic polysulfone resin (A), an amide-based solvent (B), a solvent (C) selected from hydrocarbons and ethers / acetals. , (A) content is 10% by weight
５０50% by weight, and the weight ratio of (B) to (C) (B /
An aromatic polysulfone resin solution composition, wherein C) satisfies 0.8 ≦ B / C ≦ 25. 2. An aromatic polysulfone resin solution composition comprising an aromatic polysulfone resin (A), an amide solvent (B), a solvent (D) selected from ketones and esters, wherein (A) ) Is from 10% by weight to 50% by weight
And the weight ratio (B / D) between (B) and (D) is 2.0 ≦ B
An aromatic polysulfone resin solution composition, wherein / D ≦ 25. 3. An aromatic polysulfone resin wherein (A) contains at least 80 mol% of a repeating structural unit represented by the following structure per molecule and has a reduced viscosity of 0.60 to 1.0 dl / g. The solution composition according to claim 1, wherein: (I) (In the formula (I), R ₁ represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a phenyl group or a halogen atom, and p is an integer of 0 to 4) Each R ₁ on the same or different nuclei may be different from each other, and each p may be different from each other.) 4. The solution composition according to claim 1, wherein the amide solvent (B) is N, N-dimethylformamide. 5. The solution composition according to claim 1, wherein the hydrocarbon is toluene. 6. The solution composition according to claim 1, wherein the acetal is methylal. 7. The solution composition according to claim 2, wherein the ketone is acetone. 8. The solution composition according to claim 2, wherein the ester is ethyl acetate. 9. An aromatic polysulfone resin film obtained by using the solution composition according to claim 1. 10. The aromatic polysulfone resin solution composition according to any one of claims 1 to 8, which is cast on a support to form a cast film containing a solvent, and the solvent is evaporated from the cast film. A method for producing an aromatic polysulfone resin film. 11. The method for producing an aromatic polysulfone resin film according to claim 10, wherein the solvent is evaporated, and further heating is performed at a temperature not lower than the glass transition temperature (Tg) of the aromatic polysulfone resin.