METHODS FOR UNIFORM ADHESIVE BONDLINE CONTROL FOR 3D COLD FORMED CURVED LAMINATE

Abstract

Embodiments of this disclosure pertains to methods for controlling adhesive bondline while cold-bending a glass substrate. The method includes forming a frame to define a viewing area at least partially surrounded by the frame; shaping the frame to include at least one curvature; positioning a spacer proximate the frame, the spacer comprising: a border area; and a protrusion extending from the border area; engaging the border area of the spacer with the frame to insert the protrusion through the viewing area, wherein the protrusion extends beyond the frame a first distance; positioning an adhesive between the frame and the glass substrate alongside the protrusion to control the bondline; engaging a glass substrate with the adhesive and the protrusion to cold form the glass substrate to the shape of the frame; and securing the glass substrate to the spacer to hold the frame against the adhesive to maintain the bondline.

Claims

1. A method for controlling adhesive bondline while cold forming a curved decorated or non-decorated glass substrate, the method comprising: positioning a spacer proximate a frame comprising a viewing area at least partially surrounded by the frame and at least one curvature, the spacer comprising: a border area; and a protrusion extending from the border area; engaging the border area of the spacer with the frame to insert the protrusion through the viewing area, wherein the protrusion extends beyond the frame a first distance; positioning an adhesive between the frame and the decorated or non-decorated glass substrate alongside the protrusion to control the bondline; engaging a decorated or non-decorated glass substrate with the adhesive and the protrusion to cold form the glass substrate to the shape of the frame; and one or both of vacuum forming and mechanically securing the decorated or non-decorated glass substrate to the spacer to hold the frame against the adhesive to maintain the bondline.

2. The method of claim 1, further comprising one or both of maintaining the first distance constant across the at least one curvature and the border area using the protrusion and maintaining a width of the adhesive constant along the border area by engaging the frame with the protrusion along the viewing area.

3. (canceled)

4. The method of claim 1, further comprising detachably coupling a spacer to the frame, wherein detachably coupling the spacer to the frame comprises coupling the spacer to the frame with removable fasteners.

5. (canceled)

6. The method of claim 1, wherein mechanically securing the glass substrate to the spacer comprises mechanically securing the glass substrate to the spacer by one or both of vacuum forming and mechanical clamping.

7. (canceled)

8. (canceled)

9. (canceled)

10. (canceled)

11. (canceled)

12. The method of claim 6, wherein mechanically securing the decorated or non-decorated glass substrate to the spacer comprises clamping together the spacer and the backing layer.

13. The method of claim 6, wherein mechanically securing the decorated or non-decorated glass substrate to the frame comprises clamping together the frame and the glass substrate without a backing layer.

14. (canceled)

15. The method of claim 1, wherein the spacer is formed of a non-stick material.

16. (canceled)

17. (canceled)

18. (canceled)

19. (canceled)

20. (canceled)

21. The method of claim 1, further comprising: curing the adhesive; and removing the spacer from the frame.

22. The method of claim 21, further comprising curing the adhesive either at RT, with actinic radiation or by thermal means.

23. A method for controlling adhesive bondline while cold forming a curved decorated or non-decorated glass substrate, the method comprising: positioning a glass substrate proximate a frame comprising a viewing area at least partially surrounded by the frame and at least one curvature; applying a spacer or gap controlling material along a perimeter of the glass substrate or a perimeter of the frame, the spacer or gap controlling material having a first height; positioning a structural adhesive between frame and the glass substrate such that the spacer or gap controlling material controls the bondline; engaging the glass substrate, the frame and the spacer or gap controlling material to cold form the glass substrate to the shape of the frame; and one or both of vacuum forming and mechanically securing the glass substrate to the frame to hold the frame against the structural adhesive to maintain the bondline.

24. The method of claim 23, wherein in one embodiment the spacer or gap controlling material is a curable adhesive bead.

25. The method of claim 23, further comprising maintaining the first distance constant across the at least one curvature and the viewing area using the adhesive bead.

26. The method of claim 23, wherein mechanically securing the glass substrate to the frame comprises mechanically securing the glass substrate to the frame by one or both of vacuum forming and mechanical clamping.

27. (canceled)

28. (canceled)

29. (canceled)

30. (canceled)

31. (canceled)

32. The method of claim 23, wherein the curable spacer material is applied to the frame, the decorated or non-decorated glass substrate.

33. (canceled)

34. The method of claim 23, wherein the structural adhesive is applied to the frame, the decorated or non-decorated glass substrate.

35. (canceled)

36. (canceled)

37. (canceled)

38. The method of claim 23, further comprising controlling a height of the adhesive bead by controlling volumetric flow of adhesive.

39. (canceled)

40. The method of claim 23, wherein the curable spacer material comprises an epoxy, a polyurethane, an acrylate, a silane modified polymer or a silicone, and the structural adhesive comprises an epoxy, a polyurethane, an acrylate, a silane modified polymer or a silicone.

41. The method of claim 23, wherein the spacer or gap controlling material is segmented or continuous.

42. (canceled)

43. (canceled)

44. The method of claim 23, further comprising curing the structural adhesive.

44. The method of claim 44, further comprising curing the structural adhesive to cold form the curved glass laminate.

45. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIGS. 1A, B and C are front, back and side views of the spacers inserted in an opening of a frame, according to one or more embodiments.

[0015] FIG. 2 is a part with Teflon® spacers, guides, and glass bonded to frame before clamping, according to one or more embodiments.

[0016] FIG. 3 is the part of FIG. 2 after clamping;

[0017] FIG. 4 shows an adhesive bead being dispensed by Robotic adhesive dispenser, according to one or more embodiments.

[0018] FIG. 5 shows a cover material with a I mm adhesive bead dispensed along the periphery of the part and in the central region for adhesive, according to one or more embodiments.

DETAILED DESCRIPTION

[0019] Reference will now be made in detail to various embodiments.

[0020] In the proposed disclosure, two approaches have been identified to achieve a uniform adhesive bondline control in a 3D cold formed curved laminate. The 1.sup.st approach includes using spacer(s), more specifically, a spacer is inserted from the vehicle mounting side of the frame into the display window opening of the frame and is temporarily attached to the frame using easy-to-remove screws. Adhesive is applied either onto the curved frame or the flat cover glass (CG) using an adhesive dispenser (manual or pneumatic dispensing applicator or robotic dispensing equipment). The CG is placed on a vacuum chuck and the frame-Teflon® spacer assembly is aligned onto the CG. The height of the Teflon® insert above the frame surface acts as a physical stop as it keeps the CG a specified distance off the frame surface. A negative (or inverse) chuck with a flat plate bolted on top holds the entire laminate together. This assembly is held in place under vacuum till the handling strength of the adhesive (minutes to few hours duration depending on the adhesive) is reached. The width of the adhesive bondline is controlled as the adhesive path remains between the edge of the CG in the laminate and the outside edge of the Teflon® insert spacer. Thus, the Teflon® insert helps control a uniform bondline (width and height) and the Teflon® spacer is removed after the adhesive is cured. It is advisable to keep the curved laminate clamped till full-cure of the adhesive (hours to days duration depending on the adhesive) is reached.

[0021] An alternative process can be considered for increased throughput: Teflon® spacer is inserted from the vehicle mounting side of the frame into the display window opening of the frame and is temporarily attached to the frame using easy-to-remove screws. The height of the Teflon® insert above the frame surface acts as a physical stop as it keeps the CG a specified distance off the frame surface. Teflon® guides are attached to the frame corners to assist with the alignment of the CG to the frame in the laminate. After the CG has been aligned to frame-Teflon® spacer assembly, an inverse frame (made of Teflon®, plastic or non-stick coated metal) is placed on top of the CG and the entire assembly is clamped together.

[0022] In another variation: Instead of the inverse frame, a sectioned-frame approach is used. Here, Curved clamp plate with flat ends (made of Teflon, plastic or non-stick coated metal) is placed over the curved region(s) of the CG surface. This Curved clamp plate, designed to account for the adhesive height and bend radius at the curvature, applies uniformly distributed downward pressure and helps prevent any adhesive non-uniformity in the curved region(s) of the laminate. The Curved clamp plate can be secured to the frame along the edge using clamps. Further, to minimize any adhesive distortion over the flat display area of the CG, a flat 1-7 mm sheet/thin plate (made of Teflon®, plastic or non-stick coated metal) can be placed which is then be secured to the frame along the edge using clamps. In yet another variation, instead of the flat sheet or thin plate, channels (made of Teflon®, plastic or non-stick coated metal) can be placed along the side/edges of the display window to clamp the flat display surface to the frame.

[0023] The above processes produce higher throughput as it does not limit the number of parts made using the vacuum chuck. The clamps are kept on till full-cure of the adhesive (hours to days duration depending on the adhesive) is reached.

[0024] FIGS. 1A, B and C are front, back and side views of the spacers inserted in an opening of a frame. In FIG. 1C, the alignment guides to align the cover glass CG on top of the frame is shown.

[0025] FIG. 2 shows a spacer, guides, and glass bonded to frame before clamping.

[0026] FIG. 3 shows the spacer, guides and glass bonded to the frame after clamping.

[0027] The 1.sup.st uniform bondline approach requires that the display lamination process is done after the cold-bending process as the spacer is inserted in the display window opening of the frame.

[0028] When the display is laminated to the cover material, there is no opening accessable. Accordingly, in such embodiments, the different approach is needed to achieve a uniform bondline control. In one or more embodiments, n the 2.sup.nd approach, using a robotic dispenser a precise adhesive volume is laid down in the form of an adhesive bead [as a line (single pass or multiple passes to achieve desired height) or dots or other patterns] along the perimeter of the display window area as well as in the curved region(s). The adhesive bead is then cured using UV or thermal means to form a cured adhesive bead. The cured adhesive bead acts as a height control and determines the height of the structural adhesive in the 3D Cold formed curve laminate. The adhesive used for the adhesive bead must be chemically compatible with the structural adhesive. The adhesive bead can be laid down either on the flat CG or on the curved frame. Structural adhesive is dispensed onto either the flat GG or curved frame and the flat GG is then cold bent to the curved frame. The height of the adhesive bead determines the final adhesive bondline height in the 3D curved laminate. The uniform width of the adhesive bondline is achieved through dispensing the right volumetric amount of the structural adhesive for the given adhesive bezel width. Different adhesive materials such as Epoxy, Polyurethane, Acrylates, Silane Modified Polymers or Silicones can be used to form the adhesive bead. This adhesive bead method is already used for display lamination method, but what makes it unique in the 3D Cold bending process that the structural adhesive bezel width in 3D Cold formed laminate is very narrow, typically 5-10 mm. Hence, very precise control of the adhesive bead is needed with minimum bead width being 1 mm.

[0029] FIG. 4 shows the robotic adhesive dispenser. FIG. 5 shows the cover material with a 1 mm adhesive bead dispensed along the periphery of the part and in the central region for adhesive.

[0030] Aspect (1) of this disclosure pertains to a method for controlling adhesive bondline while cold forming a curved decorated or non-decorated glass substrate, the method comprising: forming a frame to define a viewing area at least partially surrounded by the frame; shaping the frame to include at least one curvature; positioning a spacer proximate the frame, the spacer comprising: a border area; and a protrusion extending from the border area; engaging the border area of the spacer with the frame to insert the protrusion through the viewing area, wherein the protrusion extends beyond the frame a first distance; positioning an adhesive between the frame and the decorated or non-decorated glass substrate alongside the protrusion to control the bondline; engaging a decorated or non-decorated glass substrate with the adhesive and the protrusion to cold form the glass substrate to the shape of the frame; and one or both of vacuum forming and mechanically securing the decorated or non-decorated glass substrate to the spacer to hold the frame against the adhesive to maintain the bondline.

[0031] Aspect (2) of this disclosure pertains to the method of Aspect (1), further comprising maintaining the first distance constant across the at least one curvature and the border area using the protrusion.

[0032] Aspect (3) of this disclosure pertains to the method of Aspect (1) or Aspect (2), further comprising maintaining a width of the adhesive constant along the border area by engaging the frame with the protrusion along the viewing area.

[0033] Aspect (4) of this disclosure pertains to the method of any one of Aspects (1) through (3), further comprising detachably coupling a spacer to the frame.

[0034] Aspect (5) of this disclosure pertains to the method of Aspect (4), wherein detachably coupling the spacer to the frame comprises coupling the spacer to the frame with removable fasteners.

[0035] Aspect (6) of this disclosure pertains to the method of any one of Aspects (1) through (5), wherein mechanically securing the glass substrate to the spacer comprises mechanically securing the glass substrate to the spacer by one or both of vacuum forming and mechanical clamping, in which as an example, further comprises positioning a backing layer against the decorated or non-decorated glass substrate opposite the spacer.

[0036] Aspect (7) of this disclosure pertains to the method of Aspect (6), wherein the backing layer comprises an inverse frame having an inverse shape of the frame.

[0037] Aspect (8) of this disclosure pertains to the method of Aspect (7), wherein the inverse frame comprises a plurality of pieces.

[0038] Aspect (9) of this disclosure pertains to the method of Aspect (8), wherein at least one of the plurality of pieces has a shape including an inverse of the at least one curvature.

[0039] Aspect (10) of this disclosure pertains to the method of Aspect (8) or Aspect (9), wherein at least one of the plurality of pieces covers the viewing area.

[0040] Aspect (11) of this disclosure pertains to the method of any one of Aspects (6) through (10), wherein the backing layer comprises a non-stick material.

[0041] Aspect (12) of this disclosure pertains to the method of any one of Aspects (6) through (11), wherein mechanically securing the decorated or non-decorated glass substrate to the spacer comprises clamping together the spacer and the backing layer.

[0042] Aspect (13) of this disclosure pertains to the method of any one of Aspects (6) through (12), wherein mechanically securing the decorated or non-decorated glass substrate to the frame comprises clamping together the frame and the glass substrate without a backing layer.

[0043] Aspect (14) of this disclosure pertains to the method of any one of Aspects (6) through (13), further comprising attaching guides to corners of the frame to align the decorated or non-decorated glass to the frame.

[0044] Aspect (15) of this disclosure pertains to the method of any one of Aspects (1) through (14), wherein the spacer is formed of a non-stick material.

[0045] Aspect (16) of this disclosure pertains to the method of any one of Aspects (1) through (15), wherein the frame is formed of a metal and the glass substrate is formed of soda lime glass, aluminosilicate glass, borosilicate glass, boroaluminosilicate glass, alkali-containing aluminosilicate glass, alkali-containing borosilicate glass, alkali-containing boroaluminosilicate glass, polycarbonate, polyimide or acrylics.

[0046] Aspect (17) of this disclosure pertains to the method of any one of Aspects (1) through (16), wherein the adhesive is applied to the decorated or non-decorated glass substrate prior to engaging the decorated or non-decorated glass substrate with the protrusion of the spacer.

[0047] Aspect (18) of this disclosure pertains to the method of any one of Aspects (1) through (17), wherein the adhesive is applied to the frame prior to engaging the decorated or non-decorated glass substrate with the protrusion of the spacer.

[0048] Aspect (19) of this disclosure pertains to the method of any one of Aspects (1) through (18), further comprising priming the decorated or non-decorated glass at a point before the engaging.

[0049] Aspect (20) of this disclosure pertains to the method of any one of Aspects (1) through (19), further comprising applying the adhesive manually or with a robot.

[0050] Aspect (21) of this disclosure pertains to the method of any one of Aspects (1) through (20), further comprising: curing the adhesive, optionally to cold form the curved glass laminate; and removing the spacer from the frame.

[0051] Aspect (22) of this disclosure pertains to the method of Aspect (21), further comprising curing the adhesive either at RT, with actinic radiation or by thermal means.

[0052] Aspect (23) of this disclosure pertains to a method for controlling adhesive bondline while cold forming a curved decorated or non-decorated glass substrate, the method comprising: forming a frame to define a viewing area at least partially surrounded by the frame; shaping the frame to include at least one curvature; positioning a glass substrate proximate the frame; applying a spacer or gap controlling material along a perimeter of the glass substrate or a perimeter of the frame, the spacer or gap controlling material having a first height; positioning a structural adhesive between frame and the glass substrate such that the spacer or gap controlling material controls the bondline; engaging the glass substrate, the frame and the spacer or gap controlling material to cold form the glass substrate to the shape of the frame; and one or both of vacuum forming and mechanically securing the glass substrate to the frame to hold the frame against the structural adhesive to maintain the bondline.

[0053] Aspect (24) of this disclosure pertains to the method of Aspect (23), wherein in one embodiment the spacer or gap controlling material is a curable adhesive bead.

[0054] Aspect (25) of this disclosure pertains to the method of Aspect (23) or Aspect (24), further comprising maintaining the first distance constant across the at least one curvature and the viewing area using the adhesive bead.

[0055] Aspect (26) of this disclosure pertains to the method of any one of Aspects (23) through (25), wherein mechanically securing the glass substrate to the frame comprises mechanically securing the glass substrate to the frame by one or both of vacuum forming and mechanical

[0056] Aspect (27) of this disclosure pertains to the method of any one of Aspects (23) through (26), wherein the backing layer comprises an inverse frame having an inverse shape of the frame.

[0057] Aspect (28) of this disclosure pertains to the method of any one of Aspects (23) through (27), wherein the backing layer comprises a non-stick material.

[0058] Aspect (29) of this disclosure pertains to the method of any one of Aspects (23) through (28), wherein mechanically securing the decorated or non-decorated glass substrate to the frame comprises clamping together the frame and the backing layer.

[0059] Aspect (30) of this disclosure pertains to the method of any one of Aspects (23) through (29), wherein mechanically securing the decorated or non-decorated glass substrate to the frame comprises clamping together the frame and the glass substrate without a backing layer.

[0060] Aspect (31) of this disclosure pertains to the method of any one of Aspects (23) through (30), wherein the frame is formed of a metal and the glass substrate is formed of soda lime glass, aluminosilicate glass, borosilicate glass, boroaluminosilicate glass, alkali-containing aluminosilicate glass, alkali-containing borosilicate glass, alkali-containing boroaluminosilicate glass, polycarbonate, polyimide or acrylic.

[0061] Aspect (32) of this disclosure pertains to the method of any one of Aspects (23) through (31), wherein the curable spacer material is applied to the frame.

[0062] Aspect (33) of this disclosure pertains to the method of any one of Aspects (23) through (32), wherein the curable spacer material is applied to the decorated or non-decorated glass substrate.

[0063] Aspect (34) of this disclosure pertains to the method of any one of Aspects (23) through (33), wherein the structural adhesive is applied to the frame.

[0064] Aspect (35) of this disclosure pertains to the method of any one of Aspects (23) through (34), wherein the structural adhesive is applied to the decorated or non-decorated glass substrate.

[0065] Aspect (36) of this disclosure pertains to the method of any one of Aspects (23) through (35), further comprising priming the decorated or non-decorated glass at a point before the engaging.

[0066] Aspect (37) of this disclosure pertains to the method of any one of Aspects (23) through (36), further comprising applying the adhesive bead with a robot.

[0067] Aspect (38) of this disclosure pertains to the method of any one of Aspects (23) through (37), further comprising controlling a height of the adhesive bead by controlling volumetric flow of adhesive.

[0068] Aspect (39) of this disclosure pertains to the method of any one of Aspects (23) through (38), wherein the structural adhesive is chemically compatible with the spacer or gap controlling material.

[0069] Aspect (40) of this disclosure pertains to the method of any one of Aspects (23) through (39), wherein the curable spacer material comprises an epoxy, a polyurethane, an acrylate, a silane modified polymer or a silicone, and the structural adhesive comprises an epoxy, a polyurethane, an acrylate, a silane modified polymer or a silicone.

[0070] Aspect (41) of this disclosure pertains to the method of any one of Aspects (23) through (40), wherein the spacer or gap controlling material is segmented.

[0071] Aspect (42) of this disclosure pertains to the method of any one of Aspects (23) through (41), wherein the spacer or gap controlling material is continuous.

[0072] Aspect (43) of this disclosure pertains to the method of any one of Aspects (23) through (42), wherein the spacer or gap controlling material is multilayered.

[0073] Aspect (44) of this disclosure pertains to the method of any one of Aspects (23) through (42), further comprising curing the structural adhesive.

[0074] Aspect (45) of this disclosure pertains to the method of Aspect (44), further comprising curing the structural adhesive to cold form the curved glass laminate.

[0075] Aspect (46) of this disclosure pertains to the method of Aspect (45), wherein the structural adhesive is either cured at room temperature, with actinic radiation or by thermal means.

[0076] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the invention.