Cover removal tab for optical products

• US 7,147,358 B2
• Filed: 12/31/2003
• Issued: 12/12/2006
• Est. Priority Date: 12/31/2003
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Freking, Anthony J., Lu, Ashok, Feng, Ren Hua, Fei, John
• Primary Examiner(s): Husar, Stephen
• Assistant Examiner(s): Neils, Peggy A.
• Application Number:
  US10/750,553
• Publication Number:
  US 20050146881A1
• Time in Patent Office: 1,077 Days
• Field of Search: 362/330, 362/339, 362/618, 362/619, 362/620, 428/1.1, 428/172, 156/250, 156/268, 156/270, 156/267, 156/344, 156/584
• US Class Current: 362/618
• CPC Class Codes: B32B 2037/268 Release layers
• CPC Class Codes: B32B 2307/418 Refractive
• CPC Class Codes: B32B 2457/20 Displays, e.g. liquid crystal displays, plasma displays
• CPC Class Codes: B32B 38/0004 Cutting, tearing or severing, e.g. bursting; Cutter details cutting in general B26D; laminating combined with punching or perforating B32B38/04; removing all or part of the layers B32B38/10; cutting in combination with laying up and registration B32B38/185 takes precedence
• CPC Class Codes: B32B 7/06 permitting easy separation
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: G02B 5/12 Reflex reflectors
• CPC Class Codes: Y10T 156/1132 Using vacuum directly against work during delaminating
• CPC Class Codes: Y10T 428/24612 Composite web or sheet

Abstract

An optical product comprised of an optical film and a protective cover has a cover removal tab attached along one edge. The cover removal tab allows the protective cover to be easily and efficiently removed from the optical film. In addition, there is no imprint of the cover removal tab on the optical film when multiple optical products are stacked or rolled up for storage, the protective cover remains the same size as the optical film, adding the cover removal tab to the optical product only requires a one punch-head converting machine, and there is minimal waste of material and time to add the cover removal tab.

Claims

1. A method of making an optical product, the method comprising:

providing an optical film sheet having a first surface and a second surface, the first surface having an array of prism elements;

laminating a protective cover sheet to the first surface of the optical film sheet to form a web;

cutting the web to form the optical product, comprised of an optical film and a protective cover, with a cover removal tab; and

cutting essentially only the optical film sheet of the web between the optical product and the cover removal tab so that the cover removal tab remains connected to the optical product by the protective cover.

2. The method of claim 1 and further comprising:

laminating a transfer tape to the second surface of the optical film sheet; and

wherein the transfer tape is cut concurrently with the web.

3. The method of claim 1 wherein the web is carried by a liner that is cut concurrently with essentially only the optical film sheet of the web.

4. The method of claim 1 wherein the optical film is a turning film.

5. The method of claim 1 wherein the optical film is a multilayer optical film.

6. The method of claim 1 wherein the optical film is a light directing film.

7. A method of making an optical product, the method comprising:

cutting essentially only an optical film sheet of a web comprised of the optical film sheet and a protective cover sheet with a first die shaped to divide an optical film and a removal tab; and

cutting the web with a second die having a shape of the optical film with the removal tab.

8. The method of claim 7 wherein the first die and the second die cut in opposite directions.

9. The method of claim 7 and further comprising:

attaching the web to a liner.

10. A method of making an optical product, the method comprising:

laminating a protective cover sheet to an optical film sheet to form a web;

severing the web to form the optical product, comprised of a protective cover and an optical film, with a removal tab; and

severing, between the optical product and the removal tab, the optical film so that the removal tab remains connected to the optical product by the protective cover.

11. The method of claim 10 wherein removing the removal tab from the optical product also removes the protective cover from the optical film.

12. The method of claim 10 wherein the optical film is a light directing film having prism elements that have apex angles of about 90°

.

13. The method of claim 10 wherein the optical film is a turning film.

14. The method of claim 10 wherein the optical film is a multilayer optical film.

15. An optical product with a removal tab comprising:

a protective cover stacked on an optical film, the protective cover being continuous between the optical product and the removal tab, the optical film being discontinuous between the optical product and the removal tab such that the removal tab is connected to the optical product by the protective cover.

16. The optical product with a removal tab of claim 15 and further comprising:

a transfer tape stacked underneath the optical film.

17. The optical product with a removal tab of claim 15 wherein the protective cover and the optical film have perimeters of equal size and shape, the perimeters being aligned.

18. The optical product with a removal tab of claim 15 wherein the optical film is a light directing film with prism elements having apex angles of about 90°

.

19. The optical product with a removal tab of claim 15 wherein the optical film is a turning film.

20. The optical product with a removal tab of claim 15 wherein the optical film is a multilayer optical film.

21. An optical product with a removal tab comprising:

an optical product comprised of a layer of protective cover stacked on a layer of optical film, the layers having aligned edges;

a tab comprised of the layers and attached to an edge of the product such that the layer of protective cover is continuous between the product and the tab; and

a cut in the layer of optical film, the cut dividing the product and the tab such that the optical film is discontinuous between the product and the tab.

22. The optical product with a removal tab of claim 21 wherein the optical product is shaped for use in an optical display.

23. The optical product with a removal tab of claim 21 wherein the tab and the layer of protective cover of the optical product are removable from the layer of optical film of the product.