Process for producing a transparent polyurethane film with energy-absorbing and antifogging properties

• US 5,116,442 A
• Filed: 11/30/1990
• Issued: 05/26/1992
• Est. Priority Date: 05/20/1988
• Status: Expired due to Fees

• Current Assignee: Saint-Gobain Vitrage
• Original Assignee: Saint-Gobain Vitrage
• Inventors: Bravet, Jean-Louis M., Daude, Gerard M.
• Primary Examiner(s): Lowe, James
• Application Number:
  US07/620,197
• Time in Patent Office: 543 Days
• Field of Search: 264/171, 264/129, 264/216, 427/161, 427/165, 427/169, 427/389.7, 427/407.2, 427/407.1, 427/163, 427/164, 156/99, 156/280
• US Class Current: 156/99
• CPC Class Codes: B32B 17/10018 comprising only one glass sheet
• CPC Class Codes: B32B 17/1077 containing polyurethane
• CPC Class Codes: C08G 18/4837 and other oxyalkylene units
• CPC Class Codes: C08G 18/5072 containing sulfur
• CPC Class Codes: C08J 2375/04 Polyurethanes
• CPC Class Codes: C08J 2433/00 Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
• CPC Class Codes: C08J 7/0427 with only one layer of a composition containing a polymer binder with more layers C08J7/042
• CPC Class Codes: C08J 7/046 Forming abrasion-resistant coatings; Forming surface-hardening coatings
• CPC Class Codes: C08J 7/054 Forming anti-misting or drip-proofing coatings
• CPC Class Codes: C08J 7/056 Forming hydrophilic coatings
• CPC Class Codes: Y10T 428/31 Surface property or characteristic of web, sheet or block
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31583 Nitrile monomer type [polyacrylonitrile, etc.]
• CPC Class Codes: Y10T 428/31601 Quartz or glass

Abstract

A polyurethane film of excellent optical quality is prepared by applying to a substrate, by reactive casting or reactive spraying, a reaction mixture of an isocyanate component and a polyol component containing at least one long difunctional polyol having a molecular weight between 500 and 10,000, containing at least partial ethylene oxide segments, with the percentage by weight of ethylene oxide segments relative to the total weight of the polyurethane being greater than 20%, at least one short diol as chain extender, with the ratio of free NCO groups of the isocyanate component to free OH groups of the polyol component being between 1.5 and 2; and contacting a surface of said applied material intended to face toward the outside of the safety glass with a surface treatment compound of an acrylic derivative or isocyanate having a functionality greater than 2.

Claims

1. A process of producing a transparent polyurethane film of high optical quality which is a useful component of safety glass as an external film, having energy-absorbing properties and whose scratch-resistance and abrasion resistance is improved by surface treatment, which comprises:

applying to a substrate a surface treatment compound of an acrylic derivative or isocyanate having a functionality greater than 2 in the form of a thin coating;

thereafter applying onto the surface of said thin coating, for the formation of a polyurethane film by reactive casting or reactive spraying, a reaction mixture of an isocyanate component and a polyol component containing at least one long difunctional polyol having a molecular weight between 500 and 10,000, containing at least partial ethylene oxide segments, with the percentage by weight of ethylene oxide segments relative to the total weight of the polyurethane being greater than 20%, at least one short diol as chain extender, with the ratio of free NCO groups of the isocyanate component to free OH groups of the polyol component ranging from 1.5 to 2;

polymerizing the materials of the applied reaction mixture and the surface treatment compound; and

removing the polymerized polyurethane layer and the attached polymerized surface material from said substrate.

2. The process of claim 1, wherein said substrate is initially coated with a release agent before being coated with said treatment compound.

5. The process of claim 1 or 3, wherein the long polyol having ethylene oxide segments has a molecular weight between 1000 and 3000.

6. The process of claim 1, wherein NCO/OH ratio of the reactive mixture ranges from 1.7 to 1.9.

7. The process of claim 1 or 3, wherein the long polyol with ethylene oxide segments is a copolymer having ethylene oxide segments and propylene oxide segments.

8. The process of claim 1 or 3 wherein the content of ethylene oxide segments in the long polyol is greater than 40% by weight.

9. The process of claim 8, wherein the long polyol is a sulfonated polyetherpolyol.

11. The process of claim 1 or 3, wherein the surface treatment compound is selected from the group consisting of acrylate monomer and methacrylate monomer, polyacrylates and polymethacrylates of low molecular weight, acrylic polymers having free hydroxyl groups, isocyanates having a functionality greater than 2, isocyanate biurets, isocyanurates, and trimeric triisocyanates.

12. The process of claim 11, wherein the triisocyanate is selected from the group consisting of biuret, the isocyanurate, and the trimer of hexamethylenediisocyanate.

13. The process of claim 11, wherein said thickness is less than 10 microns.

14. The process of claim 1 or 3, wherein the coated film of the treatment compound has a thickness less than 20 microns.

3. A process of producing a transparent polyurethane film of high optical quality which is a useful component of safety glass as an external film, having energy-absorbing properties and whose scratch-resistance and abrasion resistance is improved by surface treatment, which comprises:

applying onto an exposed surface of a substrate, by reactive casting or reactive spraying, a reaction mixture of an isocyanate component and a polyol component containing at least one long difunctional polyol having a molecular weight between 500 and 10,000, containing at least partial ethylene oxide segments, with the percentage by weight of ethylene oxide segments relative to the total weight of the polyurethane being greater than 20%, at least one short diol as chain extender, with the ratio of free NCO groups of the isocyanate component to free OH groups of the polyol component ranging from 1.5 to 2;

polymerizing the materials of the applied reaction mixture;

removing the polymerized polyurethane layer from said substrate;

combining the polymerized layer with a pane of glass or plastic material;

contacting the exposed surface of the polymerized polyurethane layer intended to face toward the outside of said safety glass with a surface treatment compound of an acrylic derivative or isocyanate having a functionality greater than 2; and

polymerizing the suface treatment compound.

4. The process of claim 3, wherein the contact of the polyurethane film surface with the surface treatment coumpound is conducted by a soaking operation.

10. The process of claim 3, wherein the polyol having a functionality greater than 2 is a hydrophilic triol.