Claims
- 1. A method of preparing polyamide acid useful for processing of semi-conductors from (i) at least one diamine and (ii) a tetracarboxylic acid dianhydride and a diaminocarbonamide in an inert solvent, which comprises the steps of
- (1) reacting (i) at least one diamine and (ii) at least one tetracarboxylic acid dianhydride and at least one diaminocarbonamide, at a temperature below 40.degree. C. to form a polyamide acid having a reduced viscosity above 0.5 dl/g at 30.degree. C., and
- (2) heating said polyamide acid in an inert solvent at a temperature between 50.degree. C. and 100.degree. C. to lower the viscosity of said polyamide acid whereby the reduced viscosity of said polyamide acid is more than 0.3 dl/g at 30.degree. C. and the solution viscosity of said polyamide acid in the inert solvent is 500 to 3,000 centipoises at 25.degree. C.,
- the reduced viscosity being measured by forming a 0.1 dl/g solution of said polyamide acid in dimethylsulfoxide and measuring the viscosity of the solution with a Ubbelohde's viscometer in accordance with Japanese Industrial Standard K 5400, and the solution viscosity being measured by measuring the viscosity of the solution of said polyamide acid in dimethylsulfoxide with a Brookfield type viscometer in accordance with Japanese Industrial Standard K 6901.
- 2. The method of claim 1, wherein the reaction of said diamine to form said polyamide acid is carried out until said reduced viscosity at 30.degree. C. reaches above 0.7 dl/g in the first step of said method, and wherein said polyamide acid is heated to lower the reduced viscosity to between 0.35 and 0.45 dl/g and the solution viscosity to between 800 and 1,500 centipoises at 25.degree. C. in said second step of said method.
- 3. The method of claim 2, wherein
- said diamine is selected from the group consisting of 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, benzidine, m-phenylene-diamine, p-phenylenediamine, 1,5-naphthalenediamine and 2,6-naphthalenediamine;
- said tetracarboxylic acid dianhydride is selected from the group consisting of pyromellitic acid dianhydride, 3,3'4,4'-diphenyltetracarboxylic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, cyclopentanetetracarboxylic acid dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 2,3,5,6-pyridinetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 3,4,9,10-perylenetetracarboxylic acid dianhydride and 4,4'-sulfonyldiphthalic acid dianhydride; and
- said diaminocarbonamide is selected from the group consisting of 4,4'-diaminodiphenyl ether-3-carbonamide, 3,4'-diaminodiphenyl ether-4-carbonamide, 3,4-diaminodiphenyl ether-3'-carbonamide, 3,3'-diaminodiphenyl ether-4-carbonamide, 4,4'-diaminodiphenylmethane-3-carbonamide, 3,4'-diaminodiphenylmethane-4-carbonamide, 3,4'-diaminodiphenylmethane-3'-carbonamide, 3,3'-diaminodiphenylmethane-4-carbonamide, 4,4'-diaminodiphenyl sulfone-3-carbonamide, 3,4'-diaminodiphenyl sulfone-4-carbonamide, 3,4'-diaminodiphenyl sulfone-3'-carbonamide, 3,3'-diaminodiphenyl sulfone-4-carbonamide, 4,4'-diaminodiphenyl sulfide-3-carbonamide, 3,4'-diaminodiphenyl sulfide-4-carbonamide, 3,3'-diaminodiphenyl sulfide-4-carbonamide, 3,4'-diaminodiphenyl sulfide-3'-carbonamide and 1,4-diaminobenzene-2-carbonamide.
- 4. The method of claim 2, wherein 4,4'-diaminodiphenylether, 4,4'-diaminodiphenylether-3-carbonamide, pyromellitic acid dianhydride and 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride are reacted in the reaction step (1).
- 5. The polyamide acid produced by the process of claim 2.
- 6. The polyamide acid produced by the process of claim 3.
- 7. The polyamide acid produced by the process of claim 4.
Priority Claims (1)
Number |
Date |
Country |
Kind |
53-84295 |
Jul 1978 |
JPX |
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Parent Case Info
This is a division of application Ser. No. 307,199 filed Sept. 30, 1981, now U.S. Pat. No. 4,447,596 which in turn is a continuation of Ser. No. 54,429, filed July 3, 1979, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4447596 |
Makino et al. |
May 1984 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
307199 |
Sep 1981 |
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Continuations (1)
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Number |
Date |
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Parent |
54429 |
Jul 1979 |
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