APPLYING ELECTROCONDUCTIVE HEATING CIRCUITS TO GLASS

• US 3,721,594 A
• Filed: 07/20/1971
• Issued: 03/20/1973
• Est. Priority Date: 07/01/1969
• Status: Expired due to Term

• Current Assignee: Milton S. Tarnopol, Thomas P. Snyder
• Original Assignee: Milton S. Tarnopol, Thomas P. Snyder
• Inventors: Tarnopol, Milton S., Snyder, Thomas P.
• Primary Examiner(s): Fritsch, Daniel J.
• Application Number:
  US05/164,263
• Time in Patent Office: 609 Days
• Field of Search: 156/89,99,102,106 161/190,193,196,199 117/211,212,213,215,217,70,71R,124 204/15,20,38,39,40,41 219/203 65/60,106,107
• US Class Current: 156/89.17
• CPC Class Codes: B32B 17/10055 with at least one intermediate air space
• CPC Class Codes: B32B 17/10174 Coatings of a metallic or dielectric material on a constituent layer of glass or polymer
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3607 Coatings of the type glass/inorganic compound/metal
• CPC Class Codes: C03C 17/3642 the multilayer coating containing a metal layer
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: C03C 17/3655 the multilayer coating containing at least one conducting layer
• CPC Class Codes: C03C 17/3673 specially adapted for use in heating devices for rear window of vehicles
• CPC Class Codes: C03C 17/3681 the multilayer coating being used in glazing, e.g. windows or windscreens
• CPC Class Codes: C03C 17/3684 the multilayer coating being used for decoration purposes
• CPC Class Codes: C03C 17/3697 one metallic layer at least being obtained by electroless plating
• CPC Class Codes: C23C 18/1608 from pretreatment step, i.e. selective pre-treatment
• CPC Class Codes: H01B 1/00 Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
• CPC Class Codes: H05B 3/86 the heating conductors being embedded in the transparent or reflecting material H05B3/845 takes precedence
• CPC Class Codes: Y10T 428/31601 Quartz or glass
• CPC Class Codes: Y10T 428/3163 Next to acetal of polymerized unsaturated alcohol [e.g., formal butyral, etc.]
• CPC Class Codes: Y10T 428/31645 Next to addition polymer from unsaturated monomers

Abstract

Applying a decorative coating or design of electroconductive material to a glass base. When the base is transparent, the resulting article is useful as a readily heated window from which fog and ice can be readily removed on heating. A frit composition having an appropriate coefficient of expansion, an appropriate maturing temperature, and which matures into a rough, porous coating, is applied to a glass sheet surface in the circuit pattern desired, the sheet is heated and then cooled rapidly to produce a tempered glass sheet having a rough, porous frit coating conforming to the pattern desired for the electroconductive heating circuit, and a conductive metal coating is selectively deposited on the rough, porous frit by electroless plating. The frit may be sensitized by incorporating a minor amount of a sensitizing metal therein or by applying a sensitizing composition.

Claims

2. heating the coated glass sheet to an elevated temperature for sufficient time to evaporate said liquid and to fuse the frit to produce a rough, porous frit coating having a pattern conforming to that desired,

3. The method as in claim 2, wherein said sensitizing step is performed between the fusing step and the electroless plating step and comprises treating the frit-coated glass sheet with a sensitizing composition of a metal taken from the class of sensitizing metals consisting of cuprous copper, stannous tin, nickel, palladium and mixtures thereof.

4. sensitizing said rough, porous frit, and

5. The method as in claim 4, wherein said sensitizing metal is incorporated in the form of a soluble compound of said sensitizing metal.

6. The method as in claim 4, wherein said source of sensitizing metal is an organic solution of a mixture of organic compounds of at least tWo of said metals.

7. The method as in claim 4, further including the step of applying to said surface a mild, acidic, etching solution that does not harm the transparent glass base but that reacts with said frit for sufficient time to increase the number of free atoms of said sensitizing metal that is exposed but insufficient time to remove said frit completely after said rapid cooling step and before said exposure to said electroless bath.

8. The method as in claim 1, wherein said finely divided sensitized ceramic frit is applied along a series of elongated grooves previously formed along the surface area of said transparent glass sheet.

9. The method as in claim 2, wherein another glass sheet having an outline that matches that of said pattern coated glass sheet, is shaped to conform to the shape imparted to said coated glass sheet, said glass sheets are assembled on opposite surfaces of an interlayer sheet of plasticized polyvinyl butyral with the coated surface facing said interlayer sheet and said glass sheets and interlayer sheet are laminated together under heat and pressure to produce a bent transparent laminate.

10. The method as in claim 2, wherein another glass sheet having an outline matching that of said coated glass sheet, is shaped to conform to the shape imparted to said coated glass sheet and said glass sheets are laminated together under heat and pressure with a polyurethane layer therebetween to produce a bent transparent laminate.