US3892889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for stabilizing moldings of high molecular weight thermo-plastic polycarbonates
Assignee: Bayer AG
•
Filing: 1973-02-28
•
Granted: 1975-07-01
•
Expires: 1993-02-28
Abstract
Abstract Articles of high molecular weight thermoplastic polycarbonates having high resistance to ultraviolet radiation while retaining good mechanical properties prepared by applying to the surface of the articles a liquid mixture containing 2 - 20 percent by weight of an ultraviolet absorber in a mixture of 10 to 80 parts by weight of one or more aliphatic C1 - C3 halogenohydrocarbons, 20 to 80 parts by weight of one or more lower aliphatic C1 - C4 alcohols, which may be halogen-substituted, and 0 to 25 parts by weight of water. The mixtures are applied to the polycarbonate at room temperature and subsequently dried at 70* - 100*C.
Inventors
- 👤 Wolfgang Cohnen
- 👤 Gunter Peilstocker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:13
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/04; C08J7/06; C08J7/065; B; B01; B01D; B01D53/00; B01D53/26; C08J2369/00
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
161 words
IN THE PROCESS FOR THE PRODUCTION OF MOLDINGS OF HIGH MOLECULAR WEIGHT THERMOPLASTIC POLYCARBONATES OF BIVALENT PHENOLS HAVING DISPERSED TO A DEPT OF FROM ABOUT 5 TO ABOUT 30 U FROM THE SURFACE, FROM ABOUT 2 TO ABOUT 30 GRAMS PER SQUARE METER OF SURFACE OF AN ULTRAVIOLENT ABSORBER, THE SURFACE BEING SEALED, WHEREIN 150 TO 300 CC/M2 OF MOLDING SURFACE) OF A STABLIZER SOLUTION ARE APPLIED TO THE MOLDING SURFACE AND THE MOLDING SURFACE THEREAFTER DRIED, THE IMPROVEMENT COMPRISING EMPLOYING AS THE STABLIZER SOLUTION A SOLUTION COMPRISING A. A LIQUID , MIXTURE COMPRISING 10-80 PARTS BY WEIGHT OF AN ALIPHATIC C1-C3 HALOGENOHYDROCARBON, 20-80 PARTS BY WEIGHT OF A LOWER ALIPHATIC C1-C4 ALCOHOL AND 0-25 PARTS BY WEIGHT OF WATER, AND B. 2-20M PARTS BY WEIGHT BASED ON THE WEIGHT OF THE LIQUID MIXTURE, OF AN ULTRAVIOLET ABSORBED FOR POLYCARBONATES SELECTED FROM THE GROUP CONSISTING OF BENZOPHENONE DERIIVATIVES, BENZOTRAZOLE DERIVATIVES, CROTONIC ACID ESTERS, ACRYLIC ACID ESTERS ANDMIXTURES OF THREE ULTRAVIOLET ABSORBERS.
Claim 2
Dependent Claim
161 words
IN THE PROCESS FOR THE PRODUCTION OF MOLDINGS OF HIGH MOLECULAR WEIGHT THERMOPLASTIC POLYCARBONATES OF BIVALENT PHENOLS HAVING DISPERSED TO A DEPT OF FROM ABOUT 5 TO ABOUT 30 U FROM THE SURFACE, FROM ABOUT 2 TO ABOUT 30 GRAMS PER SQUARE METER OF SURFACE OF AN ULTRAVIOLENT ABSORBER, THE SURFACE BEING SEALED, WHEREIN 150 TO 300 CC/M2 OF MOLDING SURFACE) OF A STABLIZER SOLUTION ARE APPLIED TO THE MOLDING SURFACE AND THE MOLDING SURFACE THEREAFTER DRIED, THE IMPROVEMENT COMPRISING EMPLOYING AS THE STABLIZER SOLUTION A SOLUTION COMPRISING A. A LIQUID , MIXTURE COMPRISING 10-80 PARTS BY WEIGHT OF AN ALIPHATIC C1-C3 HALOGENOHYDROCARBON, 20-80 PARTS BY WEIGHT OF A LOWER ALIPHATIC C1-C4 ALCOHOL AND 0-25 PARTS BY WEIGHT OF WATER, AND B. 2-20M PARTS BY WEIGHT BASED ON THE WEIGHT OF THE LIQUID MIXTURE, OF AN ULTRAVIOLET ABSORBED FOR POLYCARBONATES SELECTED FROM THE GROUP CONSISTING OF BENZOPHENONE DERIIVATIVES, BENZOTRAZOLE DERIVATIVES, CROTONIC ACID ESTERS, ACRYLIC ACID ESTERS ANDMIXTURES OF THREE ULTRAVIOLET ABSORBERS.
Claim 3
Dependent Claim
42 words
The process of claim 1 wherein the stabilizer solution is applied to the molding surface of the polycarbonate by dipping the moldings into the stabilizer solution for 5 to about 60 seconds and allowing excess solution to drip off prior to drying.
Claim 4
Dependent Claim
11 words
The process of claim 1 wherein the halogenohydrocarbon is a chlorohydrocarbon.
Claim 5
Dependent Claim
26 words
The process of claim 1 wherein the ultraviolet absorber is selected from the group consisting of benzophenone derivatives, benzotriazole derivatives and mixtures of these ultraviolet absorbers.
Claim 6
Dependent Claim
12 words
The process of claim 4 wherein the benzophenone derivatives have the formula
Claim 7
Dependent Claim
11 words
The process of claim 5 wherein the halogenohydrocarbon is a chlorohydrocarbon.
Claim 8
Dependent Claim
26 words
The process of claim 6 whereiN the chloro hydrocarbons are selected from the group consisting of dichloromethane, trichloromethane, 1,2-dichloroethane, 1,2-dichloropropane, 1,1,2-trichloroethane and mixtures of these chlorohydrocarbons.
Claim 9
Dependent Claim
32 words
The process of claim 7 wherein the moldings are immersed in the stabilizer solution for a period of 5 to 60 seconds and thereafter dried at a temperature of 70* to 100*C.
Claim 10
Dependent Claim
30 words
The process of claim 7 wherein the stabilizer solution is applied to the surface of the molding and the molding is thereafter dried at a temperature of 70* to 100*C.
Claim 11
Dependent Claim
88 words
The process of claim 7 wherein the liquid mixture comprises 30 to 50 parts by weight of a chloro hydrocarbon selected from the group consisting of 1,2-dichloroethane and 1,1,2-trichloroethane, 45 to 50 parts by weight of a lower aliphatic C1 to C4 alcohol, and 0 to 22.5 parts by weight of water and wherein the ultraviolet absorber is 2.5 to 4.0 percent by weight based on the weight of the liquid mixture of an absorber selected from the group consisting of 2-hydroxy-4-methoxy benzophenone, 2-(2''-hydroxy-5''-methylphenyl)benzotriazole, 2-(2''-hydroxy-3'',5''-diamyl)benzotriazole and 2-(2''-hydroxy-3'',5''-ditertiary butylphenyl)benzotriazole.
Claim 12
Dependent Claim
116 words
A process for the stabilization of moldings of high molecular weight polycarbonates against simultaneous exposure to UV irradiation, heat and moisture comprising applying to the surface of the moldings 150 - 300 cc/m2 (of molding surface) of a solution comprising a. a liquid mixture comprising 10 - 80 parts by weight of an aliphatic C1 - C3 halogenohydrocarbon; 20 - 80 parts by weight of a lower aliphatic c1 - C4 alcohol and 0 - 25 parts by weight of water, and b. 2 - 20 parts by weight, based on the weight of the liquid mixture, of an ultraviolet absorber for polycarbonates, and thereafter drying the moldings at a temperature of between 70* - 100*C.
Claim 13
Dependent Claim
116 words
A process for the stabilization of moldings of high molecular weight polycarbonates against simultaneous exposure to UV irradiation, heat and moisture comprising applying to the surface of the moldings 150 - 300 cc/m2 (of molding surface) of a solution comprising a. a liquid mixture comprising 10 - 80 parts by weight of an aliphatic C1 - C3 halogenohydrocarbon; 20 - 80 parts by weight of a lower aliphatic c1 - C4 alcohol and 0 - 25 parts by weight of water, and b. 2 - 20 parts by weight, based on the weight of the liquid mixture, of an ultraviolet absorber for polycarbonates, and thereafter drying the moldings at a temperature of between 70* - 100*C.
Claim 14
Dependent Claim
118 words
A process for the stabilization of moldings of high molecular weight polycarbonates against simultaneous exposure to UV irradiation, heat and moisture comprising immersing the moldings of the polycarbonate for a period of from 5 to 60 seconds in a stabilizer solution comprising a. a liquid mixture comprising 10 - 80 parts by weight of an aliphatic C1 - C3 halogenohydrocarbon; 20 - 80 parts by weight of a lower aliphatic C1 - C4 alcohol and 0 - 25 parts by weight of water, and b. 2 - 20 parts by weight, based on the weight of the liquid mixture, of an ultraviolet absorber for polycarbonates, and thereafter drying the moldings at a temperature of from 70* to 100*C.
Claim 15
Dependent Claim
118 words
A process for the stabilization of moldings of high molecular weight polycarbonates against simultaneous exposure to UV irradiation, heat and moisture comprising immersing the moldings of the polycarbonate for a period of from 5 to 60 seconds in a stabilizer solution comprising a. a liquid mixture comprising 10 - 80 parts by weight of an aliphatic C1 - C3 halogenohydrocarbon; 20 - 80 parts by weight of a lower aliphatic C1 - C4 alcohol and 0 - 25 parts by weight of water, and b. 2 - 20 parts by weight, based on the weight of the liquid mixture, of an ultraviolet absorber for polycarbonates, and thereafter drying the moldings at a temperature of from 70* to 100*C.
Claim 16
Dependent Claim
18 words
The process of claim 12 wherein the moldings are dried at a temperature of from 90* - 95*C.
References Cited (Backward Citations)
US2976259A
Cited
US3043709A
Cited
US3309219A
Cited
US3309220A
Cited
US3519462A
Cited
US3617330A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |