# US 4,395,461 A · Method for making silicon coated polycarbonates and article obtained therefrom

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 4,395,461 A
- Document ID: US4395461A
- Status: Granted
- Kind: A
- Application number: 06/314,165
- Filed: 1981-10-23
- Granted: 1983-07-26
- Earliest claimed: 1981-10-23
- Assignees: General Electric Company
- Inventors: Ta-Yen Ching
- Web page: https://patentgrep.com/patent/US4395461A

## CPC

- C08J 7/043: Improving the adhesiveness of the coatings per se, e.g. forming primers (adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50)
- C08J 7/0427: {with only one layer of a composition containing a polymer binder (with more layers C08J7/042)}
- C08J 7/046: Forming abrasion-resistant coatings; Forming surface-hardening coatings
- C08J 2369/00: Characterised by the use of polycarbonates; Derivatives of polycarbonates
- C08J 2483/04: Polysiloxanes
- Y10T 428/31507: Of polycarbonate
- Y10T 428/31663: As siloxane, silicone or silane
- C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A method is provided for improving the weatherability of a polycarbonate substrate by initially treating the surface of the polycarbonate substrate with a solution of a hydrolyzed silylated organic U.V. screen followed by the application of a curable silicone hardcoat composition onto the treated substrate.

## Claims

### Claim 1

A method for making a composite of a polycarbonate substrate and a silicon hardcoat having improved weatherability which comprises,
(1) treating a polycarbonate substrate with a solution of the hydrolysis product of a silylated organic UV screen which has been allowed to hydrolyze for a period not exceeding about three days and curing the applied hydrolyzate on the treated substrate at a temperature of from 75.degree. C. to 150.degree. C. and
(2) applying onto the treated polycarbonate substrate a silicone hardcoat composition and thereafter heating the resulting composite to a temperature in the range of from 75.degree. C. to 150.degree. C. until the applied hardcoat composition is cured.

### Claim 2 (depends on 1)

A method in accordance with claim 1, were the silylated organic UV screen has the formula, ##STR10## where R.sup.1 is a C.sub.(1-13) monovalent hydrocarbon radical or substituted monovalent hydrocarbon radical, R.sup.2 is a C.sub.(1-8) aliphatic organic radical selected from alkyl radicals, alkyl ether radicals, alkyl ester radicals, alkyl ketone radicals, alkylene radicals and C.sub.(7-13) aralkyl radicals, Q is selected from ##STR11## Y is H or OH, Z is H, OH, OQ.sup.1 or OM, where at least one Z is OH if Y is H, M is C.sub.m H.sub.2m+1 and m is an integer equal to 1 to 18 inclusive, X is selected from ##STR12## R.sup.3 is a member selected from the class consisting of hydrogen, C.sub.(1-8) alkoxy, carboxy, halogen, hydroxy, amino, carbethoxy and D-CH.sub.2 (CH.sub.2).sub.n Si(OR.sup.2).sub.3, R.sup.4 is a member selected from the class consisting of hydrogen, halogen, hydroxy, C.sub.(1-8) alkyl and C.sub.(1-8) alkoxy, R.sup.5 is a member selected from the class consisting of hydrogen, C.sub.(1-8) alkyl, C.sub.(1-8) alkoxy and halogen, D is selected from --NH-- or O, X.sup.1 is selected from R.sup.3 or ##STR13## Y.sup.1 is R.sup.5 or --CH.sub.2 (CH.sub.2).sub.n (OR.sup.2).sub.3,
Q.sup.1 is
--CH.sub.2 (CH.sub.2).sub.n Si(R.sup.1).sub.x (OR.sup.2).sub.y,
Z.sup.1 is ##STR14## x is 0, 1 or 2, y is 1, 2 or 3, x+y is 3 and n is 0, 1 or 2, a and b are integers equal to 1 to 3 inclusive, a+b is equal to 3, and c is equal to 0 or 1.

### Claim 3 (depends on 1)

A method in accordance with claim 1, where the silicone hardcoat comprises a dispersion of colloidal silica in an aliphatic alcohol-water solution of the partial condensate of a silanol of the formula RSi(OH).sub.3, where R is selected from the group consisting of C.sub.(1-3) alkyl and C.sub.(6-13) aryl, at least 70 weight percent of the silanol being CH.sub.3 SI(OH).sub.3, said composition containing 10 to 50 weight percent solids, said solids consisting essentially of 10 to 70 weight percent colloidal silica and 30 to 90 weight percent of the partial condensate, said composition having a pH of from 3.5 to 8.0.

### Claim 4 (depends on 1)

A method in accordance with claim 1, where the silylated organic UV screen is 4-[.gamma.(triethoxysilyl)propoxy]-2-hydroxybenzophenone.

### Claim 5 (depends on 1)

A polycarbonate silicone hardcoat composite made in accordance with claim 1.