Scratch resistant optical films and method for producing same

• US 5,635,278 A
• Filed: 02/03/1995
• Issued: 06/03/1997
• Est. Priority Date: 02/03/1995
• Status: Expired due to Term

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Williams, Todd R.
• Primary Examiner(s): LONEY, DONALD J
• Application Number:
  US08/382,982
• Time in Patent Office: 851 Days
• Field of Search: 428/167, 428/172, 428/141, 428/409, 428/419, 428/423.1, 428/424.2, 428/425.1, 428/425.6, 428/474.4, 428/475.2, 428/479.3, 428/480, 428/481
• US Class Current: 428/172
• CPC Class Codes: B29D 11/00 Producing optical elements, e.g. lenses or prisms grinding or polishing of optical elements B24B; constructional form of optical elements G02B; optical parts of spectacles G02C7/00
• CPC Class Codes: B29K 2995/0087 Wear resistance
• CPC Class Codes: C09K 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: G02B 1/105 Protective coatings
• CPC Class Codes: G02B 1/111 using layers comprising organic materials
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: G02B 5/0215 the surface having a regular structure
• CPC Class Codes: G02B 5/0231 the surface having microprismatic or micropyramidal shape macroscopic prism arrays G02B5/045
• CPC Class Codes: G02B 5/0268 characterized by the fabrication or manufacturing method
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/2457 Parallel ribs and/or grooves
• CPC Class Codes: Y10T 428/24612 Composite web or sheet
• CPC Class Codes: Y10T 428/31 Surface property or characteristic of web, sheet or block
• CPC Class Codes: Y10T 428/31533 Of polythioether
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31573 Next to addition polymer of ethylenically unsaturated monomer
• CPC Class Codes: Y10T 428/31591 Next to cellulosic
• CPC Class Codes: Y10T 428/31601 Quartz or glass
• CPC Class Codes: Y10T 428/31725 : Of polyamide
• CPC Class Codes: Y10T 428/31736 : Next to polyester
• CPC Class Codes: Y10T 428/31779 : Next to cellulosic
• CPC Class Codes: Y10T 428/31786 : Of polyester [e.g., alkyd, etc.]
• CPC Class Codes: Y10T 428/3179 : Next to cellulosic

Abstract

A film that exhibits increased scratch resistant characteristics. The film is formed from a layer of crosslinkable oligomeric resin composition on a base. The film is made by: forming the layer of crosslinkable oligomeric resin composition on the base, and curing the resin composition to an extent that the film exhibits a haze decrease of less than or equal to 60 percent after abrading according to the ASTM D-968-81 procedure using 200 milliliters of sand. Preferably, the layer has a microstructure of alternating tips and grooves. Such films are useful in backlit displays which are useful in computers and the like.

Claims

1. An article comprising:

a base; and

a layer formed from a crosslinkable oligomeric resin composition on the base, and wherein the layer exhibits a haze increase of less than or equal to 60 percent after the layer is abraded according to ASTM D-968-81 procedure using 200 milliliters of sand.

2. The article of claim 1 wherein the layer comprises a microstructure of alternating tips and grooves.

3. The article of claim 2 wherein the tips have an included angle in the approximate range of 70°

to 120°

.

4. The article of claim 1 wherein the layer comprises a flat film and has a haze increase of less than or equal to 30 percent after the microstructure is abrasion tested according to the ASTM D-968-81 procedure using 200 milliliters of sand.

5. The article of claim 1 wherein the microstructure bearing article exhibits a haze increase of less than 40 after the microstructure is abrasion tested according to the ASTM D-968-81 procedure using 200 milliliters of sand.

6. The article of claim 1 wherein the cured crosslinkable oligomeric resin composition exhibits an elongation at break of greater than 50 percent when the resin composition is evaluated according to ASTM D-882-91 procedure.

7. The article of claim 1 wherein the crosslinkable oligomeric resin composition forms a polymer having a tensile modulus of less than 6.8×

10⁸ pascals when evaluated according to ASTM D-882-91 procedure.

8. The article of claim 1 wherein the base is selected from the group consisting of polyethylene terephthalate, polycarbonate, cellulose acetate butyrate, cellulose acetate propionate, polyether sulfone, polymethyl methacrylate, polyurethane, polyester, polyvinyl chloride, glass, or combinations thereof.

9. The article of claim 1 wherein the crosslinkable oligomeric resin composition comprises at least one resin selected from the group consisting of acrylate or thioacrylate terminated polythioether oligomer, acrylated liquid polysulfide oligomer, polyether based urethane acrylate oligomer, polyester based urethane acrylate oligomer, iso-octyl acrylate, N-iso butoxymethyl methacrylamide, N-vinyl caprolactam, hexandiol diacrylate, or combinations thereof.

10. The article of claim 1 and further including a crosslinking agent.

11. The article of claim 1 and further including a photoinitiator.

12. The article of claim 11 wherein the photoinitiator is approximately 1 percent by weight of the crosslinkable oligomeric resin composition.

13. The article of claim 1 wherein the base has a sputter etched surface adjacent the alternating tips and grooves.