US4639344A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing formed articles of aromatic polyamide-imide resin
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1984-06-06
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Granted: 1987-01-27
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Expires: 2004-06-06
Abstract
Abstract In a process for producing a formed article of aromatic polyamide-imide resin by compression-molding at the temperature lower than the melting temperature of the resin, the improvement which comprises subjecting the resin, prior to the molding, to heat treatment in an oxygen-containing gas under conditions satisfying the following equation logt>/=a1+a2T+a3T2+a4T3, wherein a1=2.5841, a2=-8.4926x10-3, a3=6.9984x10-6, and a4=-2.0449x10-8; t and T represent the heat-treatment time in hour and the heat-treatment temperature in DEG C., respectively; and 200 DEG C.</=T</=400 DEG C.
Inventors
- 👤 Katsuji Ueno
- 👤 Kenji Nagaoka
- 👤 Akira Miyashita
- 👤 Satoshi Ebisu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:39
CPC Classifications
C; C08; C08J; C08J3/00; B; B29; B29B; B29B13/00; B29B13/02; B29B13/021; B29C; B29C43/00; B29C43/003; C08J2379/00; C08J2379/04; C08J2379/08; Y; Y10; Y10S; Y10S264/00; Y10S264/65; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
112 words
In a process for producing a formed articles of aromatic polyamide-imide resin by compression-molding at a temperature lower than the melting temperature of the resin, said aromatic polyamide-imide resin comprising a substantially single recurring unit represented by the formula ##STR12## the improvement which comprises subjecting the resin, prior to molding, to heat treatment in an oxygen-containing gas under conditions satisfying the following equation logt≧a.sub.1 +a.sub.2 T+a.sub.3 T.sup.2 +a.sub.4 T.sup.3, wherein a 1 =2.5841, a 2 =-8.4926×10 -3 , a 3 =6.9984×10 -6 , and a N/ =-2.0449×10 -8 ; t represents the lower limit for the heat-treatment time in hours and T represents the heat-treatment temperature in °C.; and 200° C.≦T≦400° C.
Claim 2
Dependent Claim
112 words
In a process for producing a formed articles of aromatic polyamide-imide resin by compression-molding at a temperature lower than the melting temperature of the resin, said aromatic polyamide-imide resin comprising a substantially single recurring unit represented by the formula ##STR12## the improvement which comprises subjecting the resin, prior to molding, to heat treatment in an oxygen-containing gas under conditions satisfying the following equation logt≧a.sub.1 +a.sub.2 T+a.sub.3 T.sup.2 +a.sub.4 T.sup.3, wherein a 1 =2.5841, a 2 =-8.4926×10 -3 , a 3 =6.9984×10 -6 , and a N/ =-2.0449×10 -8 ; t represents the lower limit for the heat-treatment time in hours and T represents the heat-treatment temperature in °C.; and 200° C.≦T≦400° C.
Claim 3
Dependent Claim
94 words
A process for producing a formed article of aromatic polyamide-imide resin according to claim 1, wherein the heat treatment is conducted under conditions satisfying the equation a.sub.1 +a.sub.2 T+a.sub.3 T.sup.2 +a.sub.4 T.sup.3 ≦logt≦b.sub.1 +b.sub.2 T+b.sub.3 T.sup.2 +b.sub.4 T.sup.3, wherein a 1 =2.5841, a 2 =-8.4926×10 -3 , a 3 =6.9984×10 -6 , a 4 =-2.0449×10 -8 , b 1 =13.7803, b 2 =-0.12268, b 3 =4.3932×10 -4 , and b 4 =-5.5711×10 -7 ; t and T represent the heat-treatment time in hour and the heat-treatment temperature in °C., respectively; and 200° C.≦T≦400° C.
Claim 4
Dependent Claim
24 words
A process for producing a formed article of aromatic polyamide-imide resin according to claim 1, wherein the heat-treatment temperature is 280° to 390° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-26 | 1990-07-28 | 1991-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-26 | 1994-07-28 | 1995-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-26 | 1998-07-28 | 1999-01-27 | $7700.00 | Window Closed / Lapsed |