Method for bonding silicone elastomers to metal substrates

• US 4,348,426 A
• Filed: 06/22/1981
• Issued: 09/07/1982
• Est. Priority Date: 06/22/1981
• Status: Expired due to Term

• Current Assignee: Lord Corporation (Parker-Hannifin Corporation)
• Original Assignee: Lord Corporation (Parker-Hannifin Corporation)
• Inventors: Blenner, Donald R., Boenig, Herman V., Auerbach, Robert A.
• Primary Examiner(s): Lawrence, Evan K.
• Application Number:
  US06/276,216
• Time in Patent Office: 442 Days
• Field of Search: 427/38, 427/41, 427/39, 148/6.15 Z, 148/6.15 R, 204/192 E
• US Class Current: 427/535
• CPC Class Codes: B05D 2530/00 Rubber or the like
• CPC Class Codes: B05D 3/142 Pretreatment
• CPC Class Codes: B05D 7/16 using synthetic lacquers or varnishes
• CPC Class Codes: C08G 77/00 Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
• CPC Class Codes: C09D 4/00 Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16

Abstract

Adhesion of silicone elastomers to metal substrates, especially zinc phosphatized metal substrates, is significantly improved by exposing the substrate to a glow discharge plasma selected from the group consisting of at least one inert gas, at least one organosilicon compound or a combination thereof, prior to the application of any adhesive materials to such substrates.

Claims

1. A method for bonding vulcanizable silicone elastomer compositions to phosphatized metal substrates comprising:

(a) exposing to a first glow discharge plasma of a gaseous medium consisting essentially of at least one non-reactive gas at least one phosphatized metal element;

(b) applying over at least one plasma-exposed surface of said phosphatized metal element an adhesive composition suitable for bonding silicone elastomers to metal;

(c) contacting said adhesively-coated surface of said plasma-exposed phosphatized metal element with a vulcanizable silicone elastomer composition; and

(d) subjecting the resultant assembly to conditions sufficient to vulcanize said elastomer and cure said adhesive.

2. A method according to claim 1 wherein said non-reactive gas is selected from the group consisting of helium, nitrogen, neon, argon, krypton and xenon.

3. A method according to claim 1 wherein said at least one non-reactive gas comprises argon.

4. A method according to claim 1 for bonding vulcanizable silicone elastomer compositions to phosphatized metal substrates comprising:

after said exposing to a first plasma of at least one non-reactive gas at least one phosphatized metal element and prior to said applying of said adhesive;

(a) exposing said first plasma-exposed phosphatized metal element to a second glow discharge plasma of a gaseous medium consisting essentially of at least one vaporized silazane monomeric compound having the formula ##STR2## wherein each R can be the same or different, and each is individually selected from the group consisting of hydrogen, halogen, saturated or unsaturated aliphatic and haloaliphatic radical having from one to 8 carbon atoms, saturated and unsaturated cycloaliphatic and halocycloaliphatic radical having 5, 6 or 7 ring carbon atoms and aromatic and haloaromatic radical having 6 or 10 nuclear carbon atoms.

5. A method according to claim 4 wherein said at least one silazane compound comprises hexamethyl disilazane.

6. A method according to claim 4 wherein said at least one non-reactive gas is selected from the group consisting of helium, nitrogen, neon, argon, krypton and kenon.

7. A method according to claim 4 wherein said at least one non-reactive gas comprises argon.

8. A method according to claim 5 wherein said at least one non-reactive gas is selected from the group consisting of helium, nitrogen, neon, argon, krypton and xenon.

9. A method according to claim 5 wherein said at least one non-reactive gas comprises argon.