CURABLE SILICONE COATING

• US 20070178321A1
• Filed: 02/01/2007
• Published: 08/02/2007
• Est. Priority Date: 02/01/2006
• Status: Abandoned Application

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Haas, Hans E.
• Application Number:
  US11/669,979
• Publication Number:
  US 20070178321A1
• Time in Patent Office: Days
• US Class Current: 428/447
• CPC Class Codes: C08G 77/16 to hydroxyl groups
• CPC Class Codes: C08L 83/04 Polysiloxanes
• CPC Class Codes: C09D 183/04 Polysiloxanes
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

A curable silicone composition is provided that includes a silanol functional silicone fluid. A crosslinker reactive with the silanol functional silicone fluid is combined with the silanol fluid to yield a capped reactive silanol fluid. The composition is provided with a propellant in an aerosol container under pressure so as to expel the capped reactive silanol fluid along with a diluent such as a nonvolatile unreactive silicone, an organic plasticizer, a volatile organic solvent, or a combination thereof. A film produced from this composition provides a plastic or rubber substrate with a high gloss finish with desirable wear properties. The inclusion of the optional diluent and the optional propellant facilitates aerosol application of the curable silicone composition as a thin film coating. An additional attribute of a curable silicone composition as described herein is that a silicone coating cures from the capped reactive silanol fluid in ambient air at 20° Celsius in 60 minutes or less and is independent of cure catalysts that contain tin, titanate, zirconate or amine. A resultant coating is applied to the sidewall of a vehicle tire as an aesthetic and protectorant.

Claims

1. A curable silicone composition comprising:

a silanol functional silicone fluid;

a crosslinker reactive with said silanol functional silicone fluid to yield a capped reactive silanol fluid;

a diluent selected from the group consisting of;

a nonvolatile unreactive silicone, an organic plasticizer, and a volatile solvent; and

a propellant capable of expelling the composition from an aerosol container.

2. The composition of claim 1 wherein said propellant is an alkane.

3. The composition of claim 1 wherein said diluent is a solvent selected from the group consisting of:

petroleum distillates liquid at 20°

C., C₁-C₂₄ aliphatic alcohols, C₆-C₂₀ aromatic alcohols, esters;

keto esters, ethers; and

combinations thereof.

4. A curable silicone composition consisting essentially of:

a silanol functional silicone fluid;

a crosslinker reactive with said silanol functional silicone fluid to yield a capped reactive silanol fluid;

an optional diluent selected from the group consisting of;

a nonvolatile silicone unreactive or organic plasticizer with said capped silanol fluid and a volatile solvent; and

an optional propellant.

5. The composition of claim 4 wherein said silanol terminated silicone fluid has a viscosity between 100 and 1,000,000 centistokes.

6. The composition of claim 4 wherein said diluent is present up to 97 total weight percent.

7. The composition of claim 4 wherein said propellant is present from 5 to 90 total weight percent.

8. The composition of claim 4 wherein said diluent comprises a polysiloxane and a solvent.

9. The composition of claim 8 wherein said solvent is selected from the group consisting of:

petroleum distillates liquid at 20°

C., C₁-C₂₄ aliphatic alcohols, C₆-C₂₀ aromatic alcohols, esters, keto esters, ethers, and combinations thereof.

10. The composition of claim 8 wherein said polysiloxane has a viscosity of from 100 centistokes to 60,000 centistokes.

11. A silicone coating comprising a cure product of a silanol fluid capped with a silane crosslinker cured in ambient air for 60 minutes or less with the proviso that said composition is independent of a condensation cure catalyst inclusive of a moiety selected from the group consisting of:

a tin atom, a titanate, a zirconate, or an amine.

12. The coating of claim 11 further comprising a nonreactive silicone diluent.

13. The coating of claim 12 wherein said silicone is present from 70 to 95 total weight percent of said coating.

14. A vehicle tire comprising:

a circular rubber substrate having a sidewall; and

a coating of claim 11 applied to the sidewall.

15. The tire of claim 14 wherein the coating is tack free.

16. The tire of claim 15 wherein the coating has a thickness of between 10 and 500 microns.