Layer-specific energy distribution delamination

• US 9,409,383 B2
• Filed: 03/20/2009
• Issued: 08/09/2016
• Est. Priority Date: 12/22/2008
• Status: Expired due to Fees

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Feinstein, Casey J., Grespan, Silvio, Sung, Kuo-Hua, Zhong, John Z., Youngs, Lynn
• Primary Examiner(s): EFTA, ALEX B
• Application Number:
  US12/408,636
• Publication Number:
  US 20100154992A1
• Time in Patent Office: 2,699 Days
• Field of Search: 156/701, 156/711, 156/712, 156/714, 156/717, 156/752, 156/753, 156/761, 156/762, 156/765, 156/710, 156/750, 156/919
• US Class Current: 1/1
• CPC Class Codes: B23K 26/00 Working by laser beam, e.g. welding, cutting or boring
• CPC Class Codes: B23K 26/06 Shaping the laser beam, e.g. by masks or multi-focusing
• CPC Class Codes: B23K 26/0604 by a combination of beams
• CPC Class Codes: B23K 26/50 Working by transmitting the laser beam through or within the workpiece
• CPC Class Codes: B23K 26/57 the laser beam entering a face of the workpiece from which it is transmitted through the workpiece material to work on a different workpiece face, e.g. for effecting removal, fusion splicing, modifying or reforming
• CPC Class Codes: B26D 1/547 having a wire-like cutting member endless wire B26D1/46; severing using a heated wire B26F3/12
• CPC Class Codes: B26D 2001/0013 consisting of a reciprocating or endless band
• CPC Class Codes: B26D 2001/006 the cutting blade having a special shape, e.g. a special outline, serrations
• CPC Class Codes: B26D 3/28 Splitting layers from work; Mutually separating layers by cutting B26D3/30 takes precedence; Recovery of plastics or other constituents of waste material containing plastics B29B17/00
• CPC Class Codes: B26D 3/282 by peeling-off
• CPC Class Codes: B26D 7/086 by vibrating, e.g. ultrasonically
• CPC Class Codes: B26D 7/10 by heating with Laser B23K26/00; severing by heating B26F
• CPC Class Codes: B32B 2038/045 Slitting
• CPC Class Codes: B32B 2310/022 Electrical resistance
• CPC Class Codes: B32B 2310/028 using vibration, e.g. sonic or ultrasonic
• CPC Class Codes: B32B 2310/0806 using electromagnetic radiation
• CPC Class Codes: B32B 2310/0825 using IR radiation
• CPC Class Codes: B32B 2310/0843 using laser
• CPC Class Codes: B32B 2310/0862 using microwave
• CPC Class Codes: B32B 2457/20 Displays, e.g. liquid crystal displays, plasma displays
• CPC Class Codes: B32B 37/12 : characterised by using adhesives
• CPC Class Codes: B32B 37/16 : with all layers existing as coherent layers before laminating
• CPC Class Codes: B32B 37/18 : involving the assembly of discrete sheets or panels only
• 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 38/16 : Drying; Softening; Cleaning
• CPC Class Codes: B32B 43/006 : Delaminating
• CPC Class Codes: B32B 7/12 : using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: G02F 1/1309 : Repairing; Testing
• CPC Class Codes: G02F 1/133308 : Support structures for LCD panels, e.g. frames or bezels
• CPC Class Codes: G02F 1/13338 : Input devices, e.g. touch panels
• CPC Class Codes: G06F 2200/1634 : Integrated protective display lid, e.g. for touch-sensitive display in handheld computer
• CPC Class Codes: G06F 2200/1635 : Stackable modules
• CPC Class Codes: G06F 3/03547 : Touch pads, in which fingers can move on a surface
• CPC Class Codes: Y10T 156/1153 : Temperature change for delamination [e.g., heating during delaminating, etc.]
• CPC Class Codes: Y10T 156/1158 : Electromagnetic radiation applied to work for delamination [e.g., microwave, uv, ir, etc.]
• CPC Class Codes: Y10T 156/1184 : Piercing layer during delaminating [e.g., cutting, etc.]
• CPC Class Codes: Y10T 156/1911 : Heating or cooling delaminating means [e.g., melting means, freezing means, etc.]
• CPC Class Codes: Y10T 156/1917 : Electromagnetic radiation delaminating means [e.g., microwave, uv, ir, etc.]
• CPC Class Codes: Y10T 156/1967 : Cutting delaminating means

Abstract

Delamination of a laminated multilayer stack is provided by generating a layer-specific energy distribution in the stack during delamination. A localized energy transferrer can generate localized heating, cooling heating, cooling, or other form of energy absorption or transmission, in a bonding layer of a multilayer stack. Localized energy transfer can include thermal energy transfer, such as heating and/or cooling, acoustic energy transfer, such as applying ultrasonic energy, electromagnetic energy transfer, such as applying laser light, directed microwaves, etc. Localized energy transfer can generate a layer-specific energy distribution that can weaken the bonding layer while reducing damage to other layers of the stack.

Claims

1. A method of delaminating a multilayer laminated stack of overlapping layers, the method comprising:

obtaining the multilayer laminated stack including a first layer having a first surface that extends substantially over the first layer, a second layer having a second surface that extends substantially over the second layer, and a bonding layer that bonds the first layer to the second layer, wherein the multilayer laminated stack is formed by laminating the first layer to the second layer using the bonding layer, wherein the first layer comprises a touch sensor layer and the second layer comprises a display layer;

applying energy to a first portion of the bonding layer such that a concentration of the energy is greater in the bonding layer than a concentration of energy in the first and second layers, the bonding layer extending substantially throughout the area of overlap of the first and second surfaces, wherein the energy weakens the bonding layer at the first portion, the first portion being disposed between respective portions of the first and second surfaces;

applying a heat sink to the multilayer laminated stack to remove thermal energy from one or more of the first layer or the second layer; and

breaking the weakened bonding layer at the first portion between the respective portions of the first and second surfaces.

2. The method of claim 1, wherein the first portion includes an exposed surface of the bonding layer, and applying the energy to the first portion includes applying a directed transmission of energy to the exposed surface of the bonding layer, while restricting the transmission of the energy to the first and second layers.

3. The method of claim 2, wherein applying the directed transmission of energy includes applying thermal energy to the exposed surface of the bonding layer.

4. The method of claim 3, wherein applying thermal energy includes applying a heated mechanical separation mechanism to the exposed surface.

5. The method of claim 1, wherein the first portion includes an exposed surface of the bonding layer, and applying energy to the first portion includes generating a directed transmission of energy from the exposed surface of the bonding layer, while restricting the transmission of the energy from the first and second layers.

6. The method of claim 5, wherein generating the directed transmission of energy includes removing thermal energy from the bonding layer through the exposed surface of the bonding layer.

7. The method of claim 6, wherein removing thermal energy includes applying a cooling mechanical separation mechanism to the exposed surface.

8. The method of claim 2, wherein applying the directed transmission of energy includes applying electromagnetic energy to the exposed surface of the bonding layer, while restricting exposure of the first and second layers to the electromagnetic energy.

9. The method of claim 8, wherein applying electromagnetic energy includes irradiating the exposed surface with one of (i) laser light, (ii) microwaves, and (iii) infrared radiation.

10. The method of claim 1, wherein the first portion includes an internal portion of the bonding layer, and applying the transmission of energy to the first portion includes focusing the energy transmission through the multilayer laminated stack, such that the energy transmission is less concentrated in each of the first and second layers than in the internal portion of the bonding layer.

11. The method of claim 2, wherein applying the directed transmission of energy includes transmitting the energy from a mechanical separator that breaks the weakened bond at the first portion of the bonding layer.

12. The method of claim 10, wherein focusing the energy transmission includes focusing a single beam of electromagnetic energy such that a focus of the beam is in the internal portion of the bonding layer.

13. The method of claim 10, wherein focusing the energy transmission includes aiming a plurality of beams of electromagnetic energy such that the beams converge in the internal portion of the bonding layer.

14. The method of claim 1, wherein the first layer comprises a cover glass layer.

15. The method of claim 1, wherein the second layer comprises a liquid crystal module (LCM) layer.

16. The method of claim 1, wherein the first layer comprises a cover glass layer and the second layer comprises a liquid crystal module (LCM) layer.

17. A method of removing a touch sensor layer from a laminated display stack of a portable mobile device, the method comprising:

obtaining the laminated display stack including the touch sensor layer having a first surface that extends substantially over the touch sensor layer, a display layer having a second surface that extends substantially over the display layer, and a bonding layer that bonds the touch sensor layer to the display layer and extends substantially throughout the area of overlap of the first and second surfaces;

applying energy to a first portion of the bonding layer to weaken the bonding layer at the first portion;

applying a heat sink to the laminated display stack to remove thermal energy from one or more of the touch sensor layer or the display layer; and

breaking the weakened bonding layer at the first portion.

18. The method of claim 17, wherein the heat sink is attached to the display layer.

19. The method of claim 17, wherein

applying energy to the first portion includes applying thermal energy to exceed a threshold temperature that weakens the bonding layer;

and

applying the heat sink maintains a temperature of the display layer below the threshold temperature.

20. The method of claim 17, wherein

applying energy to the bonding layer includes:

varying an intensity of the energy applied to the first portion over time.

21. The method of claim 17, wherein:

the applying energy to the first portion includes applying thermal energy to the bonding layer; and

applying the heat sink maintains the temperature of the display layer below a temperature that will damage the display layer.

22. A method of delaminating a laminated display stack, the method comprising:

obtaining the laminated display stack including a touch sensor layer having a first surface that extends substantially over the touch sensor layer, a display layer having a second surface that extends substantially over the display layer, and a bonding layer that bonds the touch sensor layer to the display layer and extends substantially throughout the area of overlap of the first and second surfaces;

periodically applying energy to a first portion of the bonding layer to weaken the bonding layer by switching between an on and off cycle, wherein applying the energy results in the display layer remaining below a temperature that will damage the display layer; and

breaking the weakened bonding layer at the first portion.

23. The method of claim 22, further comprising:

coupling a heat sink to the laminated display stack to remove thermal energy from one or more of;

the display layer or the touch sensor layer.

24. The method of claim 22, further wherein the energy is periodically applied using a heated cutting wire.

25. The method of claim 24, wherein breaking the bonding layer is performed using the heated cutting wire.

26. The method of claim 22, wherein:

periodically applying energy to the bonding layer raises a temperature of the bonding layer above a threshold temperature that weakens the bonding layer.

27. A method of delaminating a laminated display stack, the method comprising:

obtaining the laminated display stack including the touch sensor layer having a first surface that extends substantially over the touch sensor layer, a display layer having a second surface that extends substantially over the display layer, and a bonding layer that bonds the touch sensor layer to the display layer and extends substantially throughout the area of overlap of the first and second surfaces;

applying energy to a first portion of the bonding layer to weaken the bonding layer by focusing an energy transmission through the laminated display stack such that the energy transmission is less concentrated in each of the touch sensor and display layers than in the bonding layer; and

breaking the weakened bonding layer at the first portion.

28. The method of claim 27, wherein focusing the energy transmission includes focusing a single beam of electromagnetic energy such that a focus of the beam is within the bonding layer.

29. The method of claim 27, wherein focusing the energy transmission includes aiming a plurality of beams of electromagnetic energy such that the beams converge in the bonding layer.