Safety glazing containing support for attachment of labels

• US 4,218,500 A
• Filed: 10/18/1978
• Issued: 08/19/1980
• Est. Priority Date: 02/12/1976
• Status: Expired due to Term

• Current Assignee: Saint-Gobain Isover (Compagnie De Saint-Gobain)
• Original Assignee: Saint-Gobain Isover (Compagnie De Saint-Gobain)
• Inventors: Radisch, Helmer
• Primary Examiner(s): McCamish, Marion
• Application Number:
  US05/952,234
• Time in Patent Office: 671 Days
• Field of Search: 428/35, 428/78, 428/210, 428/417, 428/425, 428/430, 428/431, 428/435, 428/436, 428/437, 428/439, 428/441, 428/442, 156/285, 156/299
• US Class Current: 428/78
• CPC Class Codes: B32B 17/10064 comprising at least two glass sheets, only one of which being an outer layer
• CPC Class Codes: B32B 17/10339 Specific parts of the laminated safety glass or glazing being colored or tinted tinted glass sheet B32B17/1011; tinted interlayer B32B17/10651
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: B32B 2307/412 Transparent
• CPC Class Codes: B32B 2307/584 Scratch resistance
• CPC Class Codes: B32B 2307/762 Self-repairing, self-healing
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: Y10T 156/1092 All laminae planar and face to face
• CPC Class Codes: Y10T 428/24926 including ceramic, glass, porcelain or quartz layer
• CPC Class Codes: Y10T 428/31525 Next to glass or quartz
• CPC Class Codes: Y10T 428/31554 Next to second layer of polyamidoester
• CPC Class Codes: Y10T 428/31576 Ester monomer type [polyvinylacetate, etc.]
• CPC Class Codes: Y10T 428/3158 Halide monomer type [polyvinyl chloride, etc.]
• CPC Class Codes: Y10T 428/31616 Next to polyester [e.g., alkyd]
• CPC Class Codes: Y10T 428/3162 Cross-linked polyester [e.g., glycerol maleate-styrene, etc.]
• CPC Class Codes: Y10T 428/31623 Next to polyamide or polyimide
• CPC Class Codes: Y10T 428/31627 Next to aldehyde or ketone condensation product
• CPC Class Codes: Y10T 428/3163 Next to acetal of polymerized unsaturated alcohol [e.g., formal butyral, etc.]
• CPC Class Codes: Y10T 428/31638 Cellulosic ester
• CPC Class Codes: Y10T 428/31645 Next to addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31649 : Ester, halide or nitrile of addition polymer

Abstract

The invention relates to safety glass comprising a silicate glass layer and a coating of an elastic material forming a protective layer on at least one side of said glass layer. The coated side has a delineated area formed of a relatively hard, scratch-resistant material to which a label may be removably attached. Thus, when the label is removed, the protective layer is not damaged.

Claims

1. In a safety windshield comprising a safety glass laminate of a plurality of solid glass sheets and an adherent transparent inner layer of polyvinylbutyral and having bonded to at least one outer glass sheet of said laminate, an adherent solid transparent layer of polyurethane, the improvement which comprises adhesively attaching to said self-healing polyurethane layer, a hard scratch-resistant plastic layer having surface dimensions of about 0.1 to about 1% of the total surface area of the self-healing layer and curing the adhesive at a temperature above about 100°

C. and a pressure above about 3 bars greater than atmospheric pressure.

2. The safety windshield of claim 1 wherein the self-healing polyurethane comprises (A) a film of polyurethane of three-dimensional network having self-healing and anti-lacerative properties and joined to (B) a film of polyurethane of linear chains having the ability to adhere to glass or plastic.

3. The safety windshield according to claim 2 wherein the polyurethane layer is a pre-formed sheet prepared by casting a monomeric mixture of (A) a polyether having a molecular weight of about 450 and obtained by the condensation of 1,2-propylene oxide with 2,2-bis(hydroxymethyl)1-butanol and having about 10.5 to about 12% free OH groups and (B) a biuret of 1,6-hexanediisocyanate containing about 21 to about 22% of free NCO groups, onto a glass plate and polymerizing the mixture under the influence of heat to form a solid thermoset polyurethane film and thereafter casting onto the previously formed thermoset polyurethane film a monomeric mixture comprising (A) a linear polyether having a mean molecular weight of about 2,000 and prepared from 1,2 propanediol and 1,2 propylene oxide and having about 1.6 to about 1.8% free OH groups and (B) 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanade having about 37.5% free NCO groups, to form a thermoplastic polyurethane film which adheres tightly to the underlying film of thermoset polyurethane.

4. In a safety windshield comprising at least one glass sheet having bonded thereto a scratch-resistant layer of self-healing polyurethane formed by curing a sheet of a liquid composition containing (1) a polyglycol ether resulting from the condensation of propylene oxide with trimethylolpropane and having about 10.5 to 12% free hydroxyls and (2) a biuret of 1,6-hexamethylene diisocyanate having about 21 to 22% isocyanate groups, the weight ratio of said biuret to said polyglycol ether being about 0.9 to 1.1;

the improvement which comprises a label support of hard scratch-resistant plastic material, of generally rectangular dimensions such that the surface area of the label support is about 0.1 to about 1% of the total area of one side of the windshield, adhesively affixed to the polyurethane layer with a layer of thermohardening adhesive.

5. A safety windshield according to claim 4 wherein the label support is made of polycarbonate, polyester or hard polyvinyl chloride.

6. A safety windshield according to claim 4 wherein the adhesive is a thermosetting aliphatic polyester polyurethane.

7. A safety windshield comprising at least one glass sheet having bonded thereto a soft plastic outer layer of self-healing polyurethane formed by curing a sheet of a liquid composition containing (1) a polyglycol ether resulting from the condensation of propylene oxide with trimethylolpropane and having about 10.5 to 12% free hydroxyls and (2) a biuret of 1,6-hexamethylene diisocyanate having about 21 to 22% isocyanate groups, the weight ratio of said biuret to said polyglycol ether being about 0.9 to 1.1;

and a label support of hard scratch-resistant plastic material bonded to the outer side of the soft plastic layer of self-healing polyurethane with a layer of adhesive material capable of withstanding peeling forces greater than the force necessary to rupture the underlying soft polyurethane such that the soft plastic is not disturbed when a label attached to the label support is removed, and said label support covering an area of about 0.1 to about 1% of the total surface area of the outer side of the self-healing polyurethane layer.

8. A safety windshield according to claim 7 wherein the label support is adhesively affixed to the polyurethane layer with a layer of thermohardening adhesive.

9. A laminated window comprising a substrate of at least one glass or plastic sheet having bonded thereto a soft plastic outer layer of self-healing polyurethane having a modulus of elasticity below 2,000 daN/cm² and an elongation to rupture in excess of 60% with less than 2% plastic deformation and formed by curing a sheet of a liquid composition containing (1) a polyglycol ether resulting from the condensation of propylene oxide with trimethylolpropane and having about 10.5 to 12% free hydroxyls and (2) a biuret of 1,6-hexamethylene diisocyanate having about 21 to 22% isocyanate groups, the weight ratio of said biuret to said polyglycol ether being about 0.9 to 1.1;

and a label support of hard scratch-resistant material bonded to the outer side of the soft plastic outer layer of self-healing polyurethane with a layer of adhesive material which is cured with heat and pressure, said label support covering an area of about 0.1 to 1% of the total surface area of the self-healing polyurethane layer.

10. A laminated window comprising a substrate of at least one glass or plastic sheet having bonded thereto a soft plastic outer layer of self-healing polyurethane having a modulus of elasticity below 2,000 daN/cm² and an elongation to rupture in excess of 60% with less than 2% plastic deformation;

and having a label support of hard scratch-resistant material bonded to the outer side of the soft plastic outer layer of self-healing polyurethane with a layer of thermohardening adhesive material which is cured with heat and pressure, said label support covering an area of about 0.1 to 1% of the total outer surface area of the self-healing polyurethane layer.

11. A method for making laminated safety glass windshields having at least one outer surface thereof coated with a self-healing anti-lacerative sheet of polyurethane with at least one delineated area suitable for removably affixing labels thereto without damaging said polyurethane layer which comprises superimposing a sheet of glass or glass composite and a sheet of the self-healing polyurethane to be joined to the glass, and a sheet of hard plastic, of rectangular dimensions and a surface area of about 0.1 to 1.0% of the total surface area of the polyurethane layer, with an adhesive coating or layer between the hard plastic label support and the polyurethane sheet, said label support located in a delineated area of the polyurethane sheet which is convenient for label attachment;

and subjecting the entire assembly to the action of heat and pressure in an autoclave in order to produce a finished laminate having an outer surface of self-healing polyurethane with a hard plastic label support affixed to said polyurethane surface.

12. A method according to claim 11 wherein the autoclave step is carried out at a temperature between about 100°

C. and about 140°

C. and a pressure between about 3 bars and about 15 bars above atmospheric pressure.

13. A method according to claim 12 wherein the laminate with label support attached is heated to a temperature between about 50°

C. and about 100°

C. and calandered prior to treatment in an autoclave.

14. A method according to claim 13 wherein the autoclaving is carried out at about 135°

C. and about 6 bars above atmospheric pressure for about one hour.

15. A laminated safety glass windshield having a hard plastic label support affixed thereto made in accordance with the method of any one of claims 11 to 14.