Protective glue and method for manufacturing seamless display unit

Abstract

The embodiment of the invention provides protective glue and a method for manufacturing a seamless display unit. The protective glue comprises the following components in percentage by weight: 60 to 95 percent of urethane acrylate oligomer, 3 to 40 percent of monomer, 1.5 to 8 percent of photoinitiator, 0 to 8 percent of coloring agent and 0.5 to 5 percent of additive. In addition, the invention also discloses a method for manufacturing the seamless display unit through the protection glue. The protective glue provided by the embodiment of the invention can form a thin and uniform protective glue layer on a substrate, and can effectively and accurately form a connection conductive pattern in a laser forming process.

Description

Technical Field

[0001] The present disclosure relates to a protective adhesive and a method for manufacturing a seamless display unit using the protective adhesive. Background Art

[0002] Due to the development of technology, consumers' demand for displays is increasing day by day. In order to provide better visual effects, optical seamless light-emitting diode (LED) splicing technology is used to manufacture displays. However, the existing optical seamless LED splicing technology still cannot completely eliminate the physical seams or black edges between panels, and thus cannot achieve true optical seamless splicing.

[0003] In view of this, how to develop a truly optically seamless spliced display is an urgent problem in this field. Summary of the Invention

[0004] Embodiments of the present disclosure provide a protective adhesive, which includes 60% to 95% by weight of a polyurethane acrylate oligomer, 3% to 40% by weight of a monomer, 1.5% to 8% by weight of a photoinitiator, 0% to 8% by weight of a colorant, and 0.5% to 5% by weight of an additive.

[0005] In some embodiments, the monomer includes a benzene ring functional group, a heterocyclic functional group, an epoxy functional group, a polycarbonate functional group, an amino functional group, or a combination thereof.

[0006] In some embodiments, the photoinitiator includes (2,4,6-trimethylbenzoyl) diphenylphosphine oxide, 1-hydroxy-cyclohexyl-phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropyl thioxanthone (2,4 isomer mixture), ethyl 4-dimethylaminobenzoate, benzoin dimethyl ether, 2-methyl-1-[4-methylthiophenyl]-2-morpholine, 4-chlorobenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, benzophenone, isooctyl 4-dimethylaminobenzoate, 2,4-diethyl xanthone, or a combination thereof.

[0007] In some embodiments, the additive includes an adhesion promoter, a leveling agent, a plasticizer, an antifoaming agent, a stabilizer, or a combination thereof.

[0008] In some embodiments, the viscosity range of the protective adhesive is between 35000 and 3500 centipoises.

[0009] The present disclosure provides a method for manufacturing a seamless display unit, including the following steps. Provide a substrate, and the substrate has a first surface, a second surface opposite to the first surface, and a side surface connecting the first surface and the second surface, and the first surface includes a first conductive circuit. Form a second conductive circuit on the second surface of the substrate, and the second conductive circuit is opposite to the first conductive circuit. Form a conductive layer on a part of the substrate, and the conductive layer extends from a part of the first surface to the side surface and covers a part of the second surface. Form a circuit protection glue layer on the conductive layer, and the circuit protection glue layer extends from the first surface to the side surface and covers the second surface. By laser forming technology, form a connection circuit pattern on the circuit protection glue layer, and a first part of the conductive layer is covered by the connection circuit pattern of the circuit protection glue layer after the laser forming technology, and a second part of the conductive layer is exposed by the connection circuit pattern of the circuit protection glue layer after the laser forming technology. Remove the second part of the conductive layer. Remove the remaining circuit protection glue layer, and the first part of the conductive layer is retained to form a connection conductive circuit connecting the first conductive circuit and the second conductive circuit on the first surface, the side surface and the second surface of the substrate.

[0010] In some embodiments, the remaining circuit protection glue layer is removed by immersing the substrate with the remaining circuit protection glue layer in a stripping agent for 5 to 30 minutes.

[0011] In some embodiments, the thickness of the circuit protection glue layer formed on the side surface is 1.5 to 2 times the thickness of the circuit protection glue layer formed on the first surface and the second surface.

[0012] In some embodiments, before forming the conductive layer on the substrate, the following steps are included. Form a substrate protection glue layer on the first surface, the second surface and the side surface of the substrate. By chamfering process, form a first chamfered surface between the first surface and the side surface of the substrate, and form a second chamfered surface between the second surface and the side surface of the substrate, where the first chamfered surface connects the first surface and the side surface, and the second chamfered surface connects the second surface and the side surface.

[0013] In some embodiments, the circuit protection glue layer extends from the first surface to the first chamfered surface and the side surface, and extends to the second chamfered surface and covers the second surface. Description of the Drawings

[0014] In order to make the objectives, features, advantages and embodiments of the present disclosure more obvious and understandable, the detailed description of the accompanying drawings is as follows:

[0015] Figure 1 is a top view schematic diagram of one stage of the method for manufacturing a seamless display unit according to some embodiments of the present disclosure.

[0016] Figure 2A is according to some embodiments of the present disclosure Figure 1 cross-sectional view of the AA' cross-sectional line.

[0017] Figure 2B is the cross-sectional view of the BB’ cross-sectional line according to some embodiments of the present disclosure. Figure 1 of the seamless display unit.

[0018] Figure 3 is a top view schematic diagram of the chamfering process in the method of manufacturing a seamless display unit according to some embodiments of the present disclosure.

[0019] Figure 4 and Figure 5 is according to some embodiments of the present disclosure Figure 3 is the cross-sectional view of the AA’ cross-sectional line.

[0020] Figure 6 is a top view schematic diagram of the process of forming a conductive layer in the method of manufacturing a seamless display unit according to some embodiments of the present disclosure.

[0021] Figure 7 is according to some embodiments of the present disclosure Figure 6 is the cross-sectional view of the AA’ cross-sectional line.

[0022] Figure 8 is a top view schematic diagram of the process of forming a protective glue layer in the method of manufacturing a seamless display unit according to some embodiments of the present disclosure.

[0023] Figure 9 is according to some embodiments of the present disclosure Figure 8 is the cross-sectional view of the AA’ cross-sectional line.

[0024] Figure 10 is a top view schematic diagram of the laser forming process in the method of manufacturing a seamless display unit according to some embodiments of the present disclosure.

[0025] Figure 11 is according to some embodiments of the present disclosure Figure 10 is the cross-sectional view of the BB’ cross-sectional line.

[0026] Figure 12 is a top view schematic diagram of the process of removing the second part of the conductive layer in the method of manufacturing a seamless display unit according to some embodiments of the present disclosure.

[0027] Figure 13A is according to some embodiments of the present disclosure Figure 12 is the cross-sectional view of the AA’ cross-sectional line.

[0028] Figure 13B is according to some embodiments of the present disclosure Figure 12 is the cross-sectional view of the BB’ cross-sectional line.

[0029] Figure 14It is a top view schematic diagram of removing a protective glue layer in a method for manufacturing a seamless display unit according to some embodiments of the present disclosure.

[0030] Figure 15A It is according to some embodiments of the present disclosure Figure 14 Cross-sectional view of the AA’ cross-sectional line.

[0031] Figure 15B It is according to some embodiments of the present disclosure Figure 14 Cross-sectional view of the BB’ cross-sectional line.

[0032]

Description of Main Element Symbols

[0033] 100: Seamless display unit 102: Substrate

[0034] 104A: First side / front side 104B: Second side / front side

[0035] 106: Side surface 108A: First chamfered surface

[0036] 108B: Second chamfered surface 110: First conductive circuit

[0037] 120: Second conductive circuit 130: Protective glue layer

[0038] 140: Conductive layer 142: First part

[0039] 144: Second part 150: Protective glue layer

[0040] 160: Connection circuit pattern 162: Connection conductive circuit

[0041] AA’, BB’: Cross-sectional lines T1, T2: Thickness

[0042] P1: First position P2: Second position

[0043] W1: Width W2: Spacing Detailed Embodiments

[0044] The spirit of the present disclosure will be clearly described below with reference to the accompanying drawings and detailed description. After any person with ordinary knowledge in the relevant technical field understands the preferred embodiments of the present disclosure, the techniques taught by the present disclosure can be changed and modified without departing from the spirit and scope of the present disclosure.

[0045] In addition, relative terms, such as "lower" and "upper", are used to describe the relationship of one element to another element shown in the figures in the text. Relative terms are understood to be used to describe different orientations of the device other than those depicted in the figures. For example, if the device in one figure is flipped, an element that was originally described as being on the "lower" side of other elements will be oriented on the "upper" side of other elements. The exemplary term "lower", depending on the specific orientation of the figure, can include both the "lower" and "upper" orientations. Similarly, if the device in the figure is flipped, an element that was originally described as being "below" or "beneath" other elements will be oriented "above" other elements. The exemplary terms "below" or "beneath" can include both the "above" and "above" orientations.

[0046] As used herein, the terms "comprising", "including", "having", "containing", etc. are open-ended terms, meaning including but not limited to.

[0047] Embodiments of the present disclosure provide a protective glue. The protective glue includes a polyurethane acrylate oligomer in a weight percentage of 60% to 95%, a monomer in a weight percentage of 3% to 40%, a photoinitiator in a weight percentage of 1.5% to 8%, a colorant in a weight percentage of 0% to 1%, and an additive in a weight percentage of 0.5% to 1%. In some embodiments, the weight percentage of the polyurethane acrylate oligomer is 75% to 90% or 70% to 85%. In some embodiments, the weight percentage of the monomer is 8% to 35% or 20% to 35%. In some embodiments, the weight percentage of the colorant is 0% to 6%.

[0048] Furthermore, the polyurethane acrylate oligomer is a photocurable oligomer. The polyurethane acrylate oligomer is a transparent and clear viscous liquid, and has excellent adhesion to glass, metal (such as aluminum alloy), or silicon chips, etc. In addition, the cured polyurethane acrylate oligomer has good flexibility and mechanical abrasion resistance.

[0049] The monomer includes a benzene ring functional group, a heterocyclic functional group, an epoxy functional group, a polycarbonate functional group, an amino functional group, or a combination thereof. The monomer having a heterocyclic functional group can adjust the curing rate, flexibility, and hardness of the protective glue. The monomer having an epoxy functional group can make the protective glue acid-resistant, for example, enabling the protective glue to withstand a 2% hydrofluoric acid aqueous solution for 5 to 15 minutes. The monomer having a polycarbonate functional group can make the protective glue alkali-resistant, for example, enabling the protective glue to withstand 5% potassium hydroxide (KOH) and 5% sodium hydroxide (NaOH). Further, the protective glue containing an amino functional group monomer and a polycarbonate functional group monomer can be more resistant to metal etchants [such as titanium (Ti) or copper (Cu) etchants], and thus, the protective glue can be applied to the temporary coating of circuits.

[0050] The photoinitiator includes (2,4,6-trimethylbenzoyl) diphenylphosphine oxide, 1-hydroxy-cyclohexyl-phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropyl thioxanthone (2,4 isomer mixture), ethyl 4-dimethylaminobenzoate, benzoin dimethyl ether, 2-methyl-1-[4-methylthiophenyl]-2-morpholine, 4-chlorobenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, benzophenone, isooctyl 4-dimethylaminobenzoate, 2,4-diethylxanthone, or a combination thereof.

[0051] The colorant is a blue pigment solution or a pink pigment solution.

[0052] In the embodiment where the colorant is a blue pigment solution, since the adhesion of the protective glue of this embodiment to the substrate (such as a glass substrate) is good at this time, it is not easy to fall off even after being ground by a grindstone. Therefore, the protective glue of this embodiment can be applied to the processes of removing sharp corners at the edge of the substrate and side grinding. In this embodiment, the curing conditions of the protective glue are 600 to 1000 mJ / cm 2 ultraviolet light irradiation for 3 to 5 seconds. Additionally, in this embodiment, the protective glue attached to the substrate can be removed by immersing the substrate with the protective glue in a stripper for 5 to 30 minutes.

[0053] In the embodiment where the colorant is a pink pigment solution, since the leveling property of the protective glue of this embodiment is good at this time, therefore, the protective glue of this embodiment can be used for precision processing in the micron scale. In some embodiments, the curing conditions of the protective glue are greater than 1000 mJ / cm 2 , 600 to 1000 mJ / cm 2 or 800 to 1000 mJ / cm 2 ultraviolet light irradiation. In some embodiments, the curing time of the protective glue is 3 to 5 seconds. In some embodiments, the protective glue can be removed from the substrate by a stripper, for example, by immersing the substrate with the protective glue in a stripper for 5 to 30 minutes to remove the protective glue.

[0054] The additives include adhesion promoters, leveling agents, plasticizers, defoamers, stabilizers, or a combination thereof. In some embodiments, the viscosity range of the protective glue is between 35000 and 3500 centipoises (cps). In some embodiments, the viscosity range of the protective glue is between 35000 and 7500 cps. The additives can adjust the viscosity and leveling properties of the protective glue, so that the protective glue has excellent leveling properties, and then form a thin and uniform protective glue layer on the substrate to be processed.

[0055] The protective glue obtained through the foregoing formula has excellent leveling property, and has good adhesion to glass, aluminum alloy, silicon wafer, etc., and the cured protective glue can resist acids and alkalis. In addition, the cured protective glue layer does not absorb water or expand, and has good dimensional stability. Therefore, the protective glue disclosed herein can be used as a temporary coating for protecting substrates or metal circuits.

[0056] Due to the various characteristics of the above protective glue, another object of the present disclosure is to provide a method for manufacturing a seamless display unit. The method for manufacturing a seamless display unit according to the present disclosure uses the protective glue of the embodiments of the present disclosure as a temporary coating for protecting substrates and / or circuits, avoiding damage to the substrates and / or circuits due to subsequent processes of forming circuits, and being able to form conductive circuits on the side of a seamless display unit (such as Figure 14 the seamless display unit 100) that connect the conductive circuits on the front and back of the display unit, and being able to reduce the gaps between display units, thereby developing a seamless splicing display device. The method for manufacturing a seamless display unit will be described below with various drawings and various embodiments.

[0057] Please refer to Figure 1 、 Figure 2A and Figure 2B , Figure 1 is a top view schematic diagram of one stage of the method for manufacturing a seamless display unit according to some embodiments of the present disclosure; Figure 2A is according to some embodiments of the present disclosure Figure 1 cross-sectional view taken along the section line AA'; Figure 2B is according to some embodiments of the present disclosure Figure 1 cross-sectional view taken along the section line BB'.

[0058] First, a substrate 102 having a first conductive circuit 110 is provided. As shown in Figure 2A and Figure 2B , the substrate 102 has a first surface (or front surface) 104A, a second surface (or back surface) 104B opposite to the first surface 104A, and a side surface 106 connecting the first surface 104A and the second surface 104B. In addition, as shown in Figure 2A , the first surface 104A of the substrate 102 includes a first conductive circuit 110, the second surface 104B of the substrate 102 includes a second conductive circuit 120, and the second conductive circuit 120 is formed opposite to the first conductive circuit 110.

[0059] Next, please refer to Figures 3 to 5 , Figure 3 is a top view schematic diagram of the chamfering process in the method for manufacturing a seamless display unit according to some embodiments of the present disclosure, Figure 4 and Figure 5 are cross-sectional views taken along the section line AA' of Figure 3 according to some embodiments of the present disclosure.

[0060] As Figure 3 and Figure 4 shown, a protective adhesive layer 130 is formed on the first surface 104A, the second surface 104B, and the side surface 106 of the substrate 102. The protective adhesive layer 130 has good adhesion to the substrate 102 and is not easily debonded after being ground by an abrasive stone. Therefore, the protective adhesive layer 130 can be applied to protect the substrate 102 in the chamfering process. In some embodiments, the protective adhesive layer 130 can be formed on the substrate 102 by processes such as spin coating, spray coating, screen printing, roller coating, or dipping.

[0061] As Figure 5 shown, through the chamfering process, a first chamfered surface 108A is formed between the first surface 104A and the side surface 106 of the substrate 102, and a second chamfered surface 108B is formed between the second surface 104B and the side surface 106 of the substrate 102. In some embodiments, after the first chamfered surface 108A and the second chamfered surface 108B are formed, the substrate 102 having the remaining protective adhesive layer 130 is immersed in a stripping agent for 5 to 30 minutes to remove the remaining protective adhesive layer 130 on the substrate 102.

[0062] Next, please refer to Figure 6 and Figure 7 , Figure 6 is a top view schematic diagram of forming a conductive layer 140 in a method of manufacturing a seamless display unit according to some embodiments of the present disclosure, Figure 7 is according to some embodiments of the present disclosure Figure 6 cross-sectional view of the AA' cross-sectional line.

[0063] As Figure 6 shown, the conductive layer 140 is formed on a part of the substrate 102, and this part of the substrate 102 is located on the side where the first conductive circuit 110 and the second conductive circuit 120 are provided. Further, as shown in Figure 7 shown, the conductive layer 140 extends from a part of the first surface 104A provided with the first conductive circuit 110 to the first chamfered surface 108A, the side surface 106, and the second chamfered surface 108B, and covers a part of the second surface 104B having the second conductive circuit 120. In some embodiments, the material of the conductive layer 140 is copper. In some embodiments, the conductive layer 140 is formed on this part of the substrate 102 by a copper plating process.

[0064] In addition, since the conductive layer 140 is formed to connect the first conductive circuit 110 and the second conductive circuit 120, therefore, as Figure 7As shown, the conductive layer 140 can cover between the first position P1 and the second position P2 of the first surface 104A and the second surface 104B. Although, Figure 7 only a part of the first conductive circuit 110 and the second conductive circuit 120 are connected by the conductive layer 140, but the present disclosure is not limited thereto.

[0065] Further, please refer to Figure 8 and Figure 9 , Figure 8 is a top view schematic diagram of forming the protective adhesive layer 150 in the method of manufacturing a seamless display unit according to some embodiments of the present disclosure, Figure 9 is according to some embodiments of the present disclosure Figure 8 cross-sectional view of the AA' cross-sectional line.

[0066] As Figure 8 shown, the protective adhesive layer 150 is formed on the conductive layer 140, the first conductive circuit 110 (if not completely covered by the conductive layer 140), the second conductive circuit 120 (if not completely covered by the conductive layer 140), and the substrate 102. And, as Figure 9 shown, the protective adhesive layer 150 extends from the first surface 104A of the substrate 102 to the first chamfered surface 108A and the side surface 106, and extends to the second chamfered surface 108B and covers the second surface 104B.

[0067] In addition, the thickness T2 of the protective adhesive layer 150 formed on the first surface 104A and the second surface 104B of the substrate 102 is less than the thickness T1 of the protective adhesive layer 150 formed on the side surface 106 of the substrate 102. In some embodiments, the thickness T1 of the protective adhesive layer 150 formed on the side surface 106 of the substrate 102 is 1.5 to 2 times the thickness T2 of the protective adhesive layer 150 formed on the first surface 104A and the second surface 104B. In some embodiments, the thickness T2 of the protective adhesive layer 150 formed on the first surface 104A and the second surface 104B of the substrate 102 is 2 to 3 micrometers (μm), and the thickness T1 of the protective adhesive layer 150 formed on the side surface 106 of the substrate 102 is 3 to 5 μm.

[0068] In some embodiments, the protective adhesive layer 150 can be formed on the substrate 102 by processes such as spin coating, screen printing, transfer printing, roller coating, or dipping. In some embodiments, the viscosity of the protective adhesive layer 150 is 35,000 to 7,500 cps. In some embodiments, the viscosity of the protective adhesive layer 150 is 3,500 cps. In some embodiments, the curing condition of the protective adhesive layer 150 is greater than 1000 mJ / cm 2。In some embodiments, the curing condition of the protective glue layer 150 is 800 to 1000 mJ / cm 2 。In some embodiments, the curing condition of the protective glue layer 150 is 600 mJ / cm 2 。In some embodiments, the curing condition of the protective glue layer 150 is 3 to 5 seconds.

[0069] Next, please refer to Figure 10 and Figure 11 , Figure 10 is a top view schematic diagram of the laser forming process in the method for manufacturing a seamless display unit according to some embodiments of the present disclosure, Figure 11 is according to some embodiments of the present disclosure Figure 10 cross-sectional view of the BB' cross-sectional line.

[0070] As Figure 10 shown, through the laser forming technology, the connection circuit pattern 160 is formed on the protective glue layer 150. The first part 142 of the conductive layer 140 (please refer to Figure 13A ) is still covered by the connection circuit pattern 160 of the protective glue layer 150 after the laser forming technology, while the second part 144 of the conductive layer 140 is exposed to the connection circuit pattern 160 of the protective glue layer 150 after the laser forming technology. It is worth mentioning that, due to the excellent leveling property of the protective glue used in the protective glue layer 150, therefore, a thin and uniform protective glue layer 150 can be formed on the substrate 102, and then when forming the connection circuit pattern 160 of the protective glue layer 150 in the laser forming process, it can be achieved in one step. Accordingly, through the thin and uniform protective glue layer 150, damage to the substrate or / and metal lines can be avoided in the laser forming process.

[0071] In some embodiments, through the laser forming technology, the line width W1 of the connection circuit pattern 160 ranges from 5 to 30 μm, and the pitch W2 between lines of the connection circuit pattern 160 ranges from 5 to 30 μm. In some embodiments, in some embodiments, the line width W1 of the connection circuit pattern 160 is less than 10 μm, and the pitch W2 between lines of the connection circuit pattern 160 is less than 10 μm. In addition, the laser forming technology can make the error of the line width W1 and the pitch W2 between lines of the connection circuit pattern 160 less than 3 μm. Accordingly, the line boundary flatness of the connection circuit pattern 160 formed by the laser forming technology is good, and the error value is small, which can greatly improve the stability of the quality of the seamless display unit.

[0072] Furthermore, please refer to Figure 12 , Figure 13A and Figure 13B , Figure 12A top - view schematic diagram of the second part 144 of the conductive layer 140 being removed in the method of manufacturing a seamless display unit according to some embodiments of the present disclosure. Figure 13A According to some embodiments of the present disclosure Figure 12 A cross - sectional view of the AA' cross - sectional line of Figure 13B According to some embodiments of the present disclosure Figure 12 A cross - sectional view of the BB' cross - sectional line of

[0073] As Figure 12 and Figure 13B shown, the second part 144 of the conductive layer 140 is removed (please refer to Figure 11 ). In some embodiments, the second part 144 of the conductive layer 140 is removed by an etching process, for example, the second part 144 of the conductive layer 140 is removed by a metal etchant [such as a copper (Cu) etchant].

[0074] As Figure 13A shown, in the laser forming process, the connection circuit pattern 160 of the protective adhesive layer 150 covers the first part 142 of the conductive layer 140, and the protective adhesive layer 150 can withstand acids and alkalis. Therefore, after the laser forming process and the etching process of the conductive layer 140, the first part 142 of the conductive layer 140 remains on the substrate 102.

[0075] Further, please refer to Figure 14 , Figure 15A and Figure 15B , Figure 14 A top - view schematic diagram of the remaining part of the protective adhesive layer 150 being removed in the method of manufacturing the seamless display unit 100 according to some embodiments of the present disclosure. Figure 15A According to some embodiments of the present disclosure Figure 14 A cross - sectional view of the AA' cross - sectional line of Figure 15B According to some embodiments of the present disclosure Figure 14 A cross - sectional view of the BB' cross - sectional line of

[0076] As Figure 14 shown, the remaining part of the protective adhesive layer 150 on the substrate 102 is removed (please refer to Figure 12 ), that is, the seamless display unit 100 of the embodiments of the present disclosure is formed. In some embodiments, the remaining protective adhesive layer 150 is removed by immersing the substrate 102 with the remaining protective adhesive layer 150 in a stripping agent for 5 to 30 minutes.

[0077] As Figure 15AAs shown, after removing the remaining protective glue layer 150, the first part 142 of the conductive layer 140 originally covered by the protective glue layer 150 is exposed, thereby forming a connecting conductive circuit 162, and the connecting conductive circuit 162 is formed between the first surface 104A, the first guiding angle surface 108A, the side surface 106, the second guiding angle surface 108B, and the second surface 104B of the substrate 102. In other words, the connecting conductive circuit 162 connects the first conductive circuit 110, extends to the first guiding angle surface 108A, the side surface 106, the second guiding angle surface 108B, and the second surface 104B, and then connects to the second conductive circuit 120 to connect the first conductive circuit 110 and the second conductive circuit 120.

[0078] As Figure 15B shown, since the first conductive circuit 110 and the second conductive circuit 120 are not provided at the position of the BB' cross-section line of the substrate, no connecting conductive circuit 162 is formed after removing the remaining protective glue layer 150.

[0079] Furthermore, by splicing seamless display units 100 including a connecting conductive circuit 162 connecting the first conductive circuit 110 and the second conductive circuit 120 to each other, an optical seamless display device is formed.

[0080] In summary, the protective glue of the disclosed embodiment has good adhesion, excellent leveling property, and acid and alkali resistance to glass, metal, silicon chips, etc. Therefore, the protective glue of the disclosed embodiment can be used as a temporary coating for protecting the substrate or / and the circuit. In addition, the protective glue layer of the disclosed embodiment can be peeled off by a special peeling agent.

[0081] In addition, due to the good adhesion and mechanical wear resistance of the protective glue, the substrate can be protected during the guiding angle process of manufacturing the seamless display unit. In addition, due to the excellent leveling property of the protective glue, a thin and uniform protective glue layer can be formed on the substrate. Therefore, in the laser forming process, a connecting conductive pattern can be effectively and accurately formed, thereby avoiding damage to the substrate and / or the circuit caused by repeated laser. And, since the protective glue is acid and alkali resistant, the connecting conductive circuit can be prevented from being damaged by the metal etching agent during the process of removing the metal layer.

[0082] Although the present disclosure has been disclosed as above with embodiments, it is not intended to limit the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to that defined by the claims.

Claims

1. A protective glue, characterized in that, it comprises: Polyurethane acrylate oligomer, with a weight percentage of 60% to 95%; Monomer, with a weight percentage of 3% to 40%; Photoinitiator, with a weight percentage of 1.5% to 8%; Colorant, with a weight percentage of 0% to 8%; and Additive, with a weight percentage of 0.5% to 5%.

2. The protective glue according to claim 1, characterized in that, wherein the monomer comprises a benzene ring functional group, a heterocyclic functional group, an epoxy functional group, a polycarbonate functional group, an amino functional group or a combination thereof.

3. The protective glue according to claim 1, characterized in that, wherein the photoinitiator comprises (2,4,6-trimethylbenzoyl) diphenylphosphine oxide, 1-hydroxy-cyclohexyl-phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropyl thioxanthone (2,4 isomer mixture), ethyl 4-dimethylaminobenzoate, benzoin dimethyl ether, 2-methyl-1-[4-methylthiophenyl]-2-morpholine, 4-chlorobenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, benzophenone, isooctyl 4-dimethylaminobenzoate, 2,4-diethylxanthone or a combination thereof.

4. The protective glue according to claim 1, characterized in that, wherein the additive comprises an adhesion promoter, a leveling agent, a plasticizer, an antifoaming agent, a stabilizer or a combination thereof.

5. The protective glue according to claim 1, characterized in that, wherein the viscosity range of the protective glue is between 35000 and 3500 centipoises.

6. A method for manufacturing a seamless display unit, characterized in that, it comprises: Providing a substrate, wherein the substrate has a first surface, a second surface opposite to the first surface and a side surface connecting the first surface and the second surface, and the first surface comprises a first conductive circuit; Forming a second conductive circuit on the second surface of the substrate, and the second conductive circuit is opposite to the first conductive circuit; Forming a conductive layer on a part of the substrate, wherein the conductive layer extends from a part of the first surface to the side surface and covers a part of the second surface; Forming a circuit protective glue layer on the conductive layer, wherein the circuit protective glue layer extends from the first surface to the side surface and covers the second surface; Forming a connection circuit pattern on the circuit protective glue layer by laser shaping technology, wherein a first part of the conductive layer is covered by the connection circuit pattern of the circuit protective glue layer after the laser shaping technology, and a second part of the conductive layer is exposed to the connection circuit pattern of the circuit protective glue layer after the laser shaping technology; Removing the second part of the conductive layer; and Removing the remaining circuit protective glue layer, and the first part of the conductive layer is retained to form a connection conductive circuit connecting the first conductive circuit and the second conductive circuit on the first surface, the side surface and the second surface of the substrate.

7. The method according to claim 6, characterized in that, wherein the remaining circuit protective glue layer is removed by soaking the substrate with the remaining circuit protective glue layer in a stripping agent for 5 to 30 minutes.

8. The method according to claim 6, characterized in that, The thickness of the circuit protection glue layer formed on the side surface is 1.5 to 2 times the thickness of the circuit protection glue layer formed on the first surface and the second surface.

9. The method according to claim 7, characterized in that, before forming the conductive layer on the substrate, it includes: forming a substrate protection glue layer on the first surface, the second surface and the side surface of the substrate; and forming a first chamfered surface between the first surface and the side surface of the substrate and a second chamfered surface between the second surface and the side surface of the substrate through a chamfering process, wherein the first chamfered surface connects the first surface and the side surface, and the second chamfered surface connects the second surface and the side surface.

10. The method according to claim 9, characterized in that, wherein the circuit protection glue layer extends from the first surface to the first chamfered surface and the side surface, and extends to the second chamfered surface and covers the second surface.

Images