Paint for silver film protection and method

• US 6,979,478 B1
• Filed: 08/01/2002
• Issued: 12/27/2005
• Est. Priority Date: 08/01/2002
• Status: Active Grant

• Current Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Original Assignee: Hilemn, LLC
• Inventors: DeNuccio, Ronald J.
• Primary Examiner(s): PADGETT, MARIANNE L
• Application Number:
  US10/210,678
• Time in Patent Office: 1,244 Days
• Field of Search: 427/508, 427/512, 427/514, 427/517, 427/518, 427/161, 427/164, 427/165, 427/168, 427/169, 427/404, 427/407.1, 427/407.2, 427/409, 427/410, 427/412.12, 427/417, 427/419.1, 427/419.5, 427/419.6, 427/162, 427/385.5, 427/386, 427/388.1, 427/388.3, 427/389.7
• US Class Current: 427/508
• CPC Class Codes: B05D 2203/35 Glass
• CPC Class Codes: B05D 2350/65 metal layer
• CPC Class Codes: B05D 3/067 Curing or cross-linking the coating
• CPC Class Codes: B05D 5/06 to obtain multicolour or other optical effects B05D5/02 takes precedence
• CPC Class Codes: C03C 17/38 at least one coating being a coating of an organic material
• CPC Class Codes: C08K 5/098 Metal salts of carboxylic acids
• CPC Class Codes: C09D 5/00 Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced electrically insulating plastics, resins or waxes H01B3/30; Filling pastes
• CPC Class Codes: C09D 7/63 organic
• CPC Class Codes: Y10T 428/31511 Of epoxy ether
• CPC Class Codes: Y10T 428/31515 As intermediate layer
• CPC Class Codes: Y10T 428/31518 Next to glass or quartz

Abstract

A paint and method are divulged for protecting the silver film of mirrors. The paint in its preferred embodiment includes a metal carboxylate which will contribute metal ions, namely stannous octoate for the contribution of stannous(II) ions in an amount of 0.5% or greater by weight. Alternate methods of the invention utilize an additional coating over the paint, such as an acrylic, epoxy or blend thereof which is UV curable. In another form of the paint, copper octoate is utilized in a minimum amount of 0.5% by weight for contribution of copper(II) ions.

Claims

1. A method of protecting a silver film deposited on a substrate to prevent the silver film from delaminating, comprising the steps of:

a) preparing a paint base by mixing a first cross linkable resin selected from the group consisting of;

alkyd, polyester, acrylic, epoxy and epoxy modified acrylic resins, a second cross linking resin selected from the group consisting of;

melamine-formaldehyde, urea-formaldehyde, isocyanates and amine resins, a modifying resin selected from the group consisting of epoxy and phenoxy resins and a metal carboxylate selected from the group consisting of;

octoates, tallates, rosinates, laurates, oleates, octadecanoates, neodecanoates, linoleates, naphthenoates, versatates and hexanoates;

b) applying the paint base to the silver film;

c) curing the paint base with heat to cross link the resins; and

d) contributing metal II ions from the selected metal carboxylate to the cured paint to thereby prevent the silver film from delaminating.

2. The method of claim 1 wherein preparing the paint base comprises the step of first selecting an acrylic resin, secondly selecting a melamine-formaldehyde resin, thirdly selecting an epoxy modifying resin and fourthly selecting a metal octoate.

3. The method of claim 1 wherein mixing a metal carboxylate comprises the step of mixing stannous octoate.

4. The method of claim 3 wherein mixing stannous octoate comprises the step of mixing stannous octoate in the amount of 1–

3% by weight.

5. The method of claim 1 wherein mixing a metal carboxylate comprises the step of mixing copper octoate.

6. The method of claim 5 wherein mixing copper octoate comprises the step of mixing a least 0.5% copper octoate by weight.

7. The method of claim 1 wherein applying the paint base comprises the step of painting the silver film with a paint base comprising 1% stannous octoate by weight.

8. The method of claim 1 wherein applying the paint base comprises the step of painting the silver film with a paint base comprising 0.5–

12% copper octoate by weight.

9. The method of claim 1 further comprising the step of coating the paint base with a UV curable resin.

10. The method of claim 9 further comprising the step of curing the UV curable resin using an ultraviolet light.