阅读说明：本技术 一种泡棉双面胶带及其制造方法 (Foam double-sided adhesive tape and manufacturing method thereof ) 是由 滕超 王国伟 李言 潘扬扬 于 2018-09-05 设计创作，主要内容包括：一种泡棉双面胶带,包括：离型材料；复合在所述离型材料上的第一压敏胶层；复合在所述第一压敏胶层上的泡棉层；复合在所述泡棉层上的第二压敏胶层；所述第一压敏胶层和第二压敏胶层中至少有一层为可移除性压敏胶层；所述可移除性压敏胶层由包括以下组分的原料制备而成：热塑性弹性体40重量份～60重量份；增粘树脂40重量份～60重量份；增强剂10重量份～20重量份；软化剂10重量份～25重量份；抗氧剂0.2重量份～5重量份；填料0.1重量份～5重量份。本发明提供的泡棉双面胶带采用特定结构,实现良好的相互作用,具有优异的粘接性能、耐环测性能、遮光性能、缓冲性能和抗剪切力性能,且具有拉伸可移除的易重工特性,特别适用于大尺寸液晶显示模组的装配。(A foam double-sided tape comprising: a release material; the first pressure-sensitive adhesive layer is compounded on the release material; the foam layer is compounded on the first pressure-sensitive adhesive layer; the second pressure-sensitive adhesive layer is compounded on the foam layer; at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer; the removable pressure-sensitive adhesive layer is prepared from the following raw materials: 40 to 60 parts by weight of a thermoplastic elastomer; 40-60 parts of tackifying resin; 10-20 parts of reinforcing agent; 10-25 parts by weight of a softener; 0.2 to 5 weight portions of antioxidant; 0.1 to 5 parts by weight of a filler. The foam double-sided tape provided by the invention adopts a specific structure, realizes good interaction, has excellent bonding performance, ring-measuring resistance, shading performance, buffering performance and shearing resistance, has the characteristics of being removable in stretching and easy to rework, and is particularly suitable for assembling large-size liquid crystal display modules.)

1. A foam double-sided tape comprising:

a release material;

the first pressure-sensitive adhesive layer is compounded on the release material;

the foam layer is compounded on the first pressure-sensitive adhesive layer;

the second pressure-sensitive adhesive layer is compounded on the foam layer;

at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer;

the removable pressure-sensitive adhesive layer is prepared from the following raw materials:

40 to 60 parts by weight of a thermoplastic elastomer;

40-60 parts of tackifying resin;

10-20 parts of reinforcing agent;

10-25 parts by weight of a softener;

0.2 to 5 weight portions of antioxidant;

0.1 to 5 parts by weight of a filler.

2. The foam double-sided tape according to claim 1, wherein the foam layer is selected from PU foam, PE foam, PP foam, EVA foam, acrylic foam or silicone foam;

the thickness of the foam layer is 100-5000 microns, and the density is 0.001g/cm³～1g/cm³。

3. The foam double-sided tape according to claim 1, wherein the thickness of the removable pressure-sensitive adhesive layer is 10 to 500 μm, 180 ° peel force >10N/25mm, tensile strength is 2 to 20MPa, and elongation at break is 200 to 2000%.

4. The foam double-sided tape according to claim 1, wherein the thermoplastic elastomer is selected from one or more of styrene block copolymer, polyolefin block copolymer, acrylic block copolymer, polyisobutylene, thermoplastic polyurethane, butyl rubber and ethylene propylene diene monomer.

5. The foam double-sided tape according to claim 1, wherein the reinforcing agent is selected from one or more of polystyrene, polyphenylene oxide, polyethylene terephthalate and polybutylene terephthalate.

6. The foam double-sided tape according to claim 1, wherein the softener is one or more selected from mineral oil, liquid rubber and synthetic plasticizers of dibasic acid esters.

7. The foam double-sided tape according to any one of claims 1 to 6, further comprising:

the film layer is arranged between the foam layer and the first pressure-sensitive adhesive layer;

the thickness of the thin film layer is 2-200 mu m.

8. A preparation method of the foam double-sided tape as claimed in any one of claims 1 to 6, comprising the following steps:

a) uniformly mixing a thermoplastic elastomer and a reinforcing agent in a solvent, and then sequentially adding tackifying resin, a softening agent, an antioxidant and a filler for mixing to obtain an adhesive dispersion liquid; then coating the adhesive dispersion liquid on a release material and drying to obtain a removable pressure-sensitive adhesive layer with one surface compounded with the release material;

b) attaching a first pressure-sensitive adhesive layer with one surface compounded with a release material to one surface of the foam layer, then attaching a second adhesive pressure-sensitive adhesive layer with one surface compounded with the release material to the other surface of the foam layer, removing the release material on the second adhesive pressure-sensitive adhesive layer, and then rolling to obtain the foam double-sided adhesive tape; at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer.

9. The method according to claim 8, wherein the step b) of attaching the foam layer further comprises:

and (3) performing primary coating or corona treatment on the surface to be adhered of the foam layer.

Technical Field

The invention relates to the technical field of adhesive tape production, in particular to a foam double-sided adhesive tape and a manufacturing method thereof.

Background

The foam cotton double-sided adhesive tape is a double-sided adhesive tape which takes foam cotton as a base material and is coated with pressure-sensitive adhesives of the same or different types on two sides, has the characteristics of excellent sealing performance, good rebound resilience, good buffering performance, strong adhesive force and the like, and has wide application in the fields of household appliances, instruments, automobile industry, battery industry and the like. The foam comprises various polymer foaming materials such as PU foam, PE foam, PP foam, EVA foam, acrylic foam, organic silicon foam and the like according to different materials.

In the field of large-size liquid crystal display, the foam double-sided adhesive is particularly applied to bonding between a liquid crystal display module and a backlight module due to the excellent performance of the foam double-sided adhesive. In recent years, as technical features in the field of large-sized liquid crystal displays are being developed toward weight reduction, high resolution, wide viewing angle, high brightness, high aperture ratio, no frame, and the like, higher demands are being made on the performance of adhesive materials. However, the foam double-sided adhesive in the prior art has the defects of adhesion performance, ring-testing resistance, buffering performance, shearing resistance, shading performance, easy removal and rework performance and the like, and the application of the foam double-sided adhesive in module assembly of large-size liquid crystal display equipment is limited.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a foam double-sided tape and a method for manufacturing the same, wherein the foam double-sided tape has excellent adhesion, buffering, light shielding and anti-shearing properties, and has stretch removability, and is particularly suitable for assembling large-sized liquid crystal display modules.

The invention provides a foam double-sided tape, which comprises:

a release material;

the first pressure-sensitive adhesive layer is compounded on the release material;

the foam layer is compounded on the first pressure-sensitive adhesive layer;

the second pressure-sensitive adhesive layer is compounded on the foam layer;

at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer;

the removable pressure-sensitive adhesive layer is prepared from the following raw materials:

40 to 60 parts by weight of a thermoplastic elastomer;

40-60 parts of tackifying resin;

10-20 parts of reinforcing agent;

10-25 parts by weight of a softener;

0.2 to 5 weight portions of antioxidant;

0.1 to 5 parts by weight of a filler.

Preferably, the foam layer is selected from PU foam, PE foam, PP foam, EVA foam, acrylic acid foam or organic silicon foam;

the thickness of the foam layer is 100-5000 microns, and the density is 0.001g/cm³～1g/cm³。

Preferably, the thickness of the removable pressure sensitive adhesive layer is 10 to 500 μm, the 180 DEG peel force is greater than 10N/25mm, the tensile strength is 2 to 20MPa, and the elongation at break is 200 to 2000%.

Preferably, the thermoplastic elastomer is selected from one or more of styrene block copolymers, polyolefin block copolymers, acrylic block copolymers, polyisobutylene, thermoplastic polyurethane, butyl rubber, and ethylene propylene diene monomer rubber.

Preferably, the reinforcing agent is selected from one or more of polystyrene, polyphenylene oxide, polyethylene terephthalate and polybutylene terephthalate.

Preferably, the softening agent is selected from one or more of mineral oil, liquid rubber and synthetic plasticizers of dibasic esters.

Preferably, the method further comprises the following steps:

the film layer is arranged between the foam layer and the first pressure-sensitive adhesive layer;

the thickness of the thin film layer is 2-200 mu m.

The invention also provides a preparation method of the foam double-sided tape, which comprises the following steps:

a) uniformly mixing a thermoplastic elastomer and a reinforcing agent in a solvent, and then sequentially adding tackifying resin, a softening agent, an antioxidant and a filler for mixing to obtain an adhesive dispersion liquid; then coating the adhesive dispersion liquid on a release material and drying to obtain a removable pressure-sensitive adhesive layer with one surface compounded with the release material;

b) attaching a first pressure-sensitive adhesive layer with one surface compounded with a release material to one surface of the foam layer, then attaching a second adhesive pressure-sensitive adhesive layer with one surface compounded with the release material to the other surface of the foam layer, removing the release material on the second adhesive pressure-sensitive adhesive layer, and then rolling to obtain the foam double-sided adhesive tape; at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer.

Preferably, the foam layer in step b) further comprises, before being attached:

and (3) performing primary coating or corona treatment on the surface to be adhered of the foam layer.

The invention provides a foam double-sided tape, which comprises: a release material; the first pressure-sensitive adhesive layer is compounded on the release material; the foam layer is compounded on the first pressure-sensitive adhesive layer; the second pressure-sensitive adhesive layer is compounded on the foam layer; at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer; the removable pressure-sensitive adhesive layer is prepared from the following raw materials: 40 to 60 parts by weight of a thermoplastic elastomer; 40-60 parts of tackifying resin; 10-20 parts of reinforcing agent; 10-25 parts by weight of a softener; 0.2 to 5 weight portions of antioxidant; 0.1 to 5 parts by weight of a filler. Compared with the prior art, the foam double-sided adhesive tape provided by the invention adopts a specific structure, realizes good interaction, fully exerts excellent stress buffering performance and interface filling performance of a foam layer on one hand, and improves bonding performance and endows a product with a tensile removable characteristic through a removable pressure-sensitive adhesive layer with specific content of components on the other hand; the foam double-sided tape provided by the invention has excellent bonding performance, ring-testing resistance, buffering performance, shading performance and shearing resistance, has the characteristics of being removable in stretching and easy to rework, and is particularly suitable for assembling large-size liquid crystal display modules. Experimental results show that the foam double-sided adhesive tape provided by the invention has good adhesiveness, high adhesive force on various surfaces such as glass, PC, stainless steel, ABS and the like, long-term stable adhesion, good curved surface resistance and anti-warping property, and good die cutting property; the adhesive has high initial adhesion and peeling force, high cohesive energy and excellent reworking performance, and can be removed from various surfaces without traces by simple lateral stretching; meanwhile, the liquid crystal display panel has good interface filling performance, so that the pasting interface has a good light blocking effect, is excellent in shading performance, and is particularly suitable for module assembly of large-size liquid crystal display equipment.

In addition, the preparation method provided by the invention can ensure that each layer has higher interlayer binding force, so that interlayer separation cannot occur in the manufacturing and subsequent product use processes; and the process is simple, easy to operate and suitable for large-scale industrial production.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a foam double-sided tape, which comprises:

a release material;

the first pressure-sensitive adhesive layer is compounded on the release material;

the foam layer is compounded on the first pressure-sensitive adhesive layer;

the second pressure-sensitive adhesive layer is compounded on the foam layer;

at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer;

the removable pressure-sensitive adhesive layer is prepared from the following raw materials:

40 to 60 parts by weight of a thermoplastic elastomer;

40-60 parts of tackifying resin;

10-20 parts of reinforcing agent;

10-25 parts by weight of a softener;

0.2 to 5 weight portions of antioxidant;

0.1 to 5 parts by weight of a filler.

In the invention, the foam double-sided tape comprises four layers from top to bottom: release material, first pressure sensitive adhesive layer, bubble cotton layer and second pressure sensitive adhesive layer.

In the invention, the release material is preferably release paper or release film; in a preferred embodiment of the present invention, the release material is a double silicon release paper/film. The source of the release material is not particularly limited in the present invention, and commercially available products known to those skilled in the art may be used. In the present invention, the thickness of the release material is preferably 50 μm to 200 μm, and more preferably 100 μm to 120 μm; the ratio of the release force of the light and heavy release surfaces of the release material is preferably 1: (1.5-5); the residual adhesion of the release material is preferably greater than 80%.

In the invention, the first pressure-sensitive adhesive layer is compounded on the release material. In a preferred embodiment of the present invention, the first pressure-sensitive adhesive layer is a removable (rubber) pressure-sensitive adhesive layer; the removable pressure-sensitive adhesive layer is prepared from the following raw materials:

40 to 60 parts by weight of a thermoplastic elastomer;

40-60 parts of tackifying resin;

10-20 parts of reinforcing agent;

10-25 parts by weight of a softener;

0.2 to 5 weight portions of antioxidant;

0.1 to 5 parts by weight of a filler.

In the present invention, the thermoplastic elastomer is preferably selected from one or more of styrene block copolymers, polyolefin block copolymers, acrylic block copolymers, polyisobutylene, thermoplastic polyurethane, butyl rubber, and ethylene propylene diene monomer, more preferably styrene block copolymers; the styrene block copolymer is preferably selected from one or more of styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene/butylene-styrene block copolymer (SEBS), and styrene-ethylene/propylene-styrene block copolymer (SEPS), and more preferably is styrene-isoprene-styrene block copolymer (SIS) and/or styrene-ethylene/propylene-styrene block copolymer (SEPS). The source of the thermoplastic elastomer is not particularly limited in the present invention, and commercially available and self-made products of the above-mentioned styrene block copolymer, polyolefin block copolymer, acrylic block copolymer, polyisobutylene, thermoplastic polyurethane, butyl rubber and ethylene propylene diene rubber, which are well known to those skilled in the art, may be used. In the present invention, the second pressure-sensitive adhesive layer includes 40 to 60 parts by weight of the thermoplastic elastomer, preferably 50 to 55 parts by weight.

In the present invention, the tackifying resin is preferably selected from one or more of terpene resins, rosin resins and petroleum resins, and more preferably terpene resins and/or rosin resins. The source of the tackifier resin is not particularly limited in the present invention, and commercially available products of the above terpene resin, rosin resin and petroleum resin, which are well known to those skilled in the art, may be used. In the present invention, the second pressure-sensitive adhesive layer includes 40 to 60 parts by weight of a tackifying resin, preferably 40 to 45 parts by weight.

In the present invention, the reinforcing agent is preferably selected from one or more of polystyrene, polyphenylene ether, polyethylene terephthalate and polybutylene terephthalate, and more preferably polystyrene and/or polyphenylene ether. The source of the reinforcing agent in the present invention is not particularly limited, and commercially available products of the above-mentioned polystyrene, polyphenylene ether, polyethylene terephthalate and polybutylene terephthalate, which are well known to those skilled in the art, can be used. In the present invention, the second pressure-sensitive adhesive layer includes 10 to 20 parts by weight of a reinforcing agent, preferably 15 to 20 parts by weight.

In the invention, the reinforcing agent has good compatibility with the thermoplastic elastomer, particularly the reinforcing agent represented by polystyrene and polyphenyl ether has good compatibility with the hard chain segment of the styrene block copolymer, and the bonding force between the hard chain segments can be improved, so that the cohesive force and the tensile strength of the pressure-sensitive adhesive layer are improved, and the pressure-sensitive adhesive layer has the characteristic of being capable of being stretched and removed. In addition, the enhancement of the cohesive energy also improves the temperature resistance of the pressure-sensitive adhesive layer.

In the present invention, the softener is preferably one or more selected from the group consisting of mineral oil, liquid rubber, and synthetic plasticizers of dibasic esters, more preferably mineral oil; the mineral oil is preferably selected from one or more of paraffin oil, naphthenic oil and aromatic oil, more preferably naphthenic oil and/or aromatic oil; the liquid rubber is preferably selected from one or more of low molecular weight polyisobutylene, polybutene and liquid polyisodibutene. The source of the softener is not particularly limited in the present invention, and commercially available products and self-products using the above synthetic plasticizers of mineral oil, liquid rubber and dibasic ester, which are well known to those skilled in the art, can be used. In the present invention, the second pressure-sensitive adhesive layer includes 10 to 25 parts by weight of a softening agent, preferably 20 parts by weight.

In the present invention, the antioxidant is preferably selected from one or more of phenol antioxidants, aniline antioxidants, sulfur compound antioxidants and benzimidazole antioxidants, and more preferably phenol antioxidants; the phenolic antioxidant is preferably a phenolic antioxidant having a large steric hindrance, and the present invention is not particularly limited thereto. The source of the antioxidant in the present invention is not particularly limited, and commercially available products of the above phenol type antioxidant, aniline type antioxidant, sulfur compound type antioxidant and benzimidazole type antioxidant, which are well known to those skilled in the art, may be used. In the present invention, the second pressure-sensitive adhesive layer includes 0.2 to 5 parts by weight of an antioxidant, preferably 0.5 to 2 parts by weight.

In the present invention, the filler is preferably selected from one or more of carbon black, black paste or black ink, and more preferably carbon black. The source of the filler in the present invention is not particularly limited, and any commercially available product of the above-mentioned carbon black, black paste or black ink known to those skilled in the art may be used. In the present invention, the second pressure-sensitive adhesive layer includes 0.1 to 5 parts by weight of a filler, preferably 0.5 to 3 parts by weight; the use amount of the filler is too small, the black dyeing effect of the pressure-sensitive adhesive is insufficient, and the light shading property of the adhesive layer is insufficient; the use of an excessive amount of the filler may affect the adhesive force and initial tack of the pressure-sensitive adhesive.

In the present invention, the thickness of the removable pressure-sensitive adhesive layer is preferably 10 to 500 μm, more preferably 50 to 200 μm; the 180 ° peel force of the removable pressure sensitive adhesive layer is preferably >10N/25 mm; the tensile strength of the removable pressure-sensitive adhesive layer is preferably 2MPa to 20MPa, and more preferably 8MPa to 15 MPa; the elongation at break of the removable pressure-sensitive adhesive layer is preferably 200% to 2000%, more preferably 1000% to 1500%.

In the invention, the removable pressure-sensitive adhesive layer adopts specific content of components, has higher initial adhesion and stripping force, simultaneously has higher cohesive energy, and can be removed from various surfaces without traces by simple lateral stretching, thereby endowing the adhesive tape with excellent reworking performance.

In other preferred embodiments of the present invention, the first pressure-sensitive adhesive layer is preferably selected from a rubber-based pressure-sensitive adhesive layer or an acrylic pressure-sensitive adhesive layer, more preferably an acrylic pressure-sensitive adhesive layer; in a preferred embodiment, the first pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer and is prepared by acrylic glue well known to those skilled in the art; the thickness of the acrylic pressure-sensitive adhesive layer is preferably 10 to 200 μm, and more preferably 40 to 100 μm; the 180 ° peel force of the acrylic pressure sensitive adhesive layer is preferably >10N/25mm, more preferably >15N/25 mm.

In the invention, the foam layer is compounded on the first pressure-sensitive adhesive layer. In the invention, the foam layer is preferably selected from high polymer foam materials such as PU foam, PE foam, PP foam, EVA foam, acrylic foam or organic silicon foam, and more preferably PU foam. In a preferred embodiment of the invention, the foam layer is preferably a commercially available PU closed cell foam, which is black in color; the black PU foam layer with high resilience is used as a base material, so that the adhesive tape has excellent stress buffering performance and interface filling performance; the good stress buffering performance ensures the long-term stability and the shock resistance buffering performance of bonding, and the good interface filling performance ensures that the bonding interface has good light ray blocking effect.

In the present invention, the thickness of the foam layer is preferably 100 to 5000 μm, more preferably 500 to 800 μm; the density of the foam layer is preferably 0.001g/cm³～1g/cm³More preferably 0.01g/cm³～0.7g/cm³. In a preferred embodiment of the invention, the foam layer has a compression set<3 percent; the compression ratio of the foam is preferably large>30 percent; the foam expansion ratio of the foam layer is preferably 2-100, more preferably 3-50, and even more preferably 3-5; when the foaming multiple is less than 3, the buffering performance is deteriorated, and the stress relieving effect and the interface filling performance are not sufficient; when the foaming ratio is more than 5, the cohesive strength is poor, the shearing resistance is weakened, and the foam is easy to tear in the using process.

In the present invention, the foam double-sided tape preferably further comprises:

and the thin film layer is arranged between the foam layer and the first pressure-sensitive adhesive layer. In the present invention, the film layer is preferably a PET layer; the PET layer is compounded on the first pressure-sensitive adhesive layer, and the foam layer is compounded on the other surface of the first pressure-sensitive adhesive layer, so that the effect of supporting the foam layer is mainly achieved, and the dimensional stability and the tensile strength of the foam layer can be improved. In a preferred embodiment of the present invention, the film layer is preferably an ultra-thin PET film, which is black in color; the ultra-thin PET film is introduced during the production of the foam layer, and is sold as a commodity together with the foam layer as a whole, to which the present invention is not particularly limited. In the present invention, the thickness of the thin film layer is preferably 2 μm to 200 μm, and more preferably 5 μm to 15 μm.

In the invention, the second pressure-sensitive adhesive layer is compounded on the foam layer. In the present invention, at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer. In a preferred embodiment of the present invention, the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer are both removable pressure-sensitive adhesive layers. In another preferred embodiment of the present invention, the first pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer, and the second pressure-sensitive adhesive layer is selected from a rubber-based pressure-sensitive adhesive layer or an acrylic pressure-sensitive adhesive layer. In another preferred embodiment of the present invention, the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer is selected from a rubber-based pressure-sensitive adhesive layer or an acrylic pressure-sensitive adhesive layer.

In a preferred embodiment of the present invention, the second pressure-sensitive adhesive layer is a removable (rubber) pressure-sensitive adhesive layer; the removable pressure-sensitive adhesive layer is prepared from the following raw materials:

40 to 60 parts by weight of a thermoplastic elastomer;

40-60 parts of tackifying resin;

10-20 parts of reinforcing agent;

10-25 parts by weight of a softener;

0.2 to 5 weight portions of antioxidant;

0.1 to 5 parts by weight of a filler.

In the present invention, the thermoplastic elastomer is preferably selected from one or more of styrene block copolymers, polyolefin block copolymers, acrylic block copolymers, polyisobutylene, thermoplastic polyurethane, butyl rubber, and ethylene propylene diene monomer, more preferably styrene block copolymers; the styrene block copolymer is preferably selected from one or more of styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene/butylene-styrene block copolymer (SEBS), and styrene-ethylene/propylene-styrene block copolymer (SEPS), and more preferably is styrene-isoprene-styrene block copolymer (SIS) and/or styrene-ethylene/propylene-styrene block copolymer (SEPS). The source of the thermoplastic elastomer is not particularly limited in the present invention, and commercially available and self-made products of the above-mentioned styrene block copolymer, polyolefin block copolymer, acrylic block copolymer, polyisobutylene, thermoplastic polyurethane, butyl rubber and ethylene propylene diene rubber, which are well known to those skilled in the art, may be used. In the present invention, the second pressure-sensitive adhesive layer includes 40 to 60 parts by weight of the thermoplastic elastomer, preferably 50 to 55 parts by weight.

In the present invention, the tackifying resin is preferably selected from one or more of terpene resins, rosin resins and petroleum resins, and more preferably terpene resins and/or rosin resins. The source of the tackifier resin is not particularly limited in the present invention, and commercially available products of the above terpene resin, rosin resin and petroleum resin, which are well known to those skilled in the art, may be used. In the present invention, the second pressure-sensitive adhesive layer includes 40 to 60 parts by weight of a tackifying resin, preferably 40 to 45 parts by weight.

In the present invention, the reinforcing agent is preferably selected from one or more of polystyrene, polyphenylene ether, polyethylene terephthalate and polybutylene terephthalate, and more preferably polystyrene and/or polyphenylene ether. The source of the reinforcing agent in the present invention is not particularly limited, and commercially available products of the above-mentioned polystyrene, polyphenylene ether, polyethylene terephthalate and polybutylene terephthalate, which are well known to those skilled in the art, can be used. In the present invention, the second pressure-sensitive adhesive layer includes 10 to 20 parts by weight of a reinforcing agent, preferably 15 to 20 parts by weight.

In the invention, the reinforcing agent has good compatibility with the thermoplastic elastomer, particularly the reinforcing agent represented by polystyrene and polyphenyl ether has good compatibility with the hard chain segment of the styrene block copolymer, and the bonding force between the hard chain segments can be improved, so that the cohesive force and the tensile strength of the pressure-sensitive adhesive layer are improved, and the pressure-sensitive adhesive layer has the characteristic of being capable of being stretched and removed.

In the present invention, the softener is preferably one or more selected from the group consisting of mineral oil, liquid rubber, and synthetic plasticizers of dibasic esters, more preferably mineral oil; the mineral oil is preferably selected from one or more of paraffin oil, naphthenic oil and aromatic oil, more preferably naphthenic oil and/or aromatic oil; the liquid rubber is preferably selected from one or more of low molecular weight polyisobutylene, polybutene and liquid polyisodibutene. The source of the softener is not particularly limited in the present invention, and commercially available products and self-products using the above synthetic plasticizers of mineral oil, liquid rubber and dibasic ester, which are well known to those skilled in the art, can be used. In the present invention, the second pressure-sensitive adhesive layer includes 10 to 25 parts by weight of a softening agent, preferably 20 parts by weight.

In the present invention, the antioxidant is preferably selected from one or more of phenol antioxidants, aniline antioxidants, sulfur compound antioxidants and benzimidazole antioxidants, and more preferably phenol antioxidants; the phenolic antioxidant is preferably a phenolic antioxidant having a large steric hindrance, and the present invention is not particularly limited thereto. The source of the antioxidant in the present invention is not particularly limited, and commercially available products of the above phenol type antioxidant, aniline type antioxidant, sulfur compound type antioxidant and benzimidazole type antioxidant, which are well known to those skilled in the art, may be used. In the present invention, the second pressure-sensitive adhesive layer includes 0.2 to 5 parts by weight of an antioxidant, preferably 0.5 to 2 parts by weight.

In the present invention, the filler is preferably selected from one or more of carbon black, black paste or black ink, and more preferably carbon black. The source of the filler in the present invention is not particularly limited, and any commercially available product of the above-mentioned carbon black, black paste or black ink known to those skilled in the art may be used. In the present invention, the second pressure-sensitive adhesive layer includes 0.1 to 5 parts by weight of a filler, preferably 0.5 to 3 parts by weight; the use amount of the filler is too small, the black dyeing effect of the pressure-sensitive adhesive is insufficient, and the light shading property of the adhesive layer is insufficient; the use of an excessive amount of the filler may affect the adhesive force and initial tack of the pressure-sensitive adhesive.

In the present invention, the thickness of the removable pressure-sensitive adhesive layer is preferably 10 to 500 μm, more preferably 50 to 200 μm; the 180 ° peel force of the removable pressure sensitive adhesive layer is preferably >10N/25 mm; the tensile strength of the removable pressure-sensitive adhesive layer is preferably 2MPa to 20MPa, and more preferably 8MPa to 15 MPa; the elongation at break of the removable pressure-sensitive adhesive layer is preferably 200% to 2000%, more preferably 1000% to 1500%.

In the invention, the removable pressure-sensitive adhesive layer adopts specific content of components, has higher initial adhesion and stripping force, simultaneously has higher cohesive energy, and can be removed from various surfaces without traces by simple lateral stretching, thereby endowing the adhesive tape with excellent reworking performance.

The foam double-sided adhesive tape provided by the invention adopts a specific structure, realizes good interaction, fully exerts excellent stress buffering performance and interface filling performance of a foam layer on one hand, and improves bonding performance and endows a product with a tensile removable characteristic through a removable pressure-sensitive adhesive layer with specific content of components on the other hand; the foam double-sided tape provided by the invention has excellent bonding performance, ring-testing resistance, buffering performance, shading performance and shearing resistance, has the characteristics of being removable in stretching and easy to rework, and is particularly suitable for assembling large-size liquid crystal display modules.

The invention also provides a preparation method of the foam double-sided tape, which comprises the following steps:

a) uniformly mixing a thermoplastic elastomer and a reinforcing agent in a solvent, and then sequentially adding tackifying resin, a softening agent, an antioxidant and a filler for mixing to obtain an adhesive dispersion liquid; then coating the adhesive dispersion liquid on a release material and drying to obtain a removable pressure-sensitive adhesive layer with one surface compounded with the release material;

b) attaching a first pressure-sensitive adhesive layer with one surface compounded with a release material to one surface of the foam layer, then attaching a second adhesive pressure-sensitive adhesive layer with one surface compounded with the release material to the other surface of the foam layer, removing the release material on the second adhesive pressure-sensitive adhesive layer, and then rolling to obtain the foam double-sided adhesive tape; at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer.

Firstly, uniformly mixing a thermoplastic elastomer and a reinforcing agent in a solvent, and then sequentially adding tackifying resin, a softening agent, an antioxidant and a filler for mixing to obtain an adhesive dispersion liquid; and then coating the adhesive dispersion liquid on a release material for drying to obtain the removable pressure-sensitive adhesive layer with one surface compounded with the release material. In the present invention, the thermoplastic elastomer, the reinforcing agent, the tackifying resin, the softening agent, the antioxidant and the filler are the same as those described in the above technical solution, and are not described herein again.

The invention mixes the thermoplastic elastomer and the intensifier in the solvent to obtain the mixed solution. In the present invention, the solvent is preferably a non-polar solvent; such as toluene and/or xylene, well known to those skilled in the art, may be employed. In the present invention, the solvent is used to dissolve the thermoplastic elastomer and the reinforcing agent, thereby ensuring good compatibility between the thermoplastic elastomer and the reinforcing agent. In the invention, the dosage ratio of the solvent to the reinforcing agent is preferably (110-160): (10-20), more preferably (130-135): 15.

the mixing mode of the present invention is not particularly limited, and preferably specifically:

firstly, dissolving the reinforcing agent in a solvent, and then adding the thermoplastic elastomer for dissolving to obtain a mixed solution. In the present invention, the solid content of the mixed solution is preferably 20% to 50%, more preferably 30%.

After the mixed solution is obtained, tackifying resin, a softening agent, an antioxidant and a filler are sequentially added into the obtained mixed solution and mixed to obtain the adhesive dispersion liquid. In the present invention, the mixing method preferably adopts a dissolving and dispersing technical scheme well known to those skilled in the art, and the present invention is not particularly limited thereto. In the present invention, the solid content of the adhesive dispersion is preferably 40% to 60%, more preferably 50%.

After the adhesive dispersion liquid is obtained, the adhesive dispersion liquid is coated on a release material and dried to obtain the removable pressure-sensitive adhesive layer with one surface compounded with the release material. In the invention, the release material is preferably release paper or release film; in a preferred embodiment of the present invention, the release material is a double silicon release paper/film. The source of the release material is not particularly limited in the present invention, and commercially available products known to those skilled in the art may be used. In the present invention, the thickness of the release material is preferably 20 μm to 200 μm, and more preferably 100 μm to 120 μm; the ratio of the release force of the light and heavy release surfaces of the release material is preferably 1: (1.5-5); the residual adhesion of the release material is preferably greater than 80%.

The coating mode is not particularly limited in the present invention, and the technical scheme of coating on the release material, which is well known to those skilled in the art, can be adopted.

In the present invention, the drying manner is preferably a stepwise curing, in order to dry the adhesive dispersion applied on the release material to remove the solvent and achieve curing, thereby obtaining a removable pressure-sensitive adhesive layer with a specific thickness. In the present invention, the temperature of the staged curing is preferably 50 to 110 ℃. In a preferred embodiment of the present invention, the curing section temperature of the stepwise curing is 60 ℃, 80 ℃, 100 ℃, 110 ℃ and 100 ℃. The device for the segmented curing is not particularly limited, and a coater with an oven satisfying the segmented curing temperature mentioned above, which is well known to those skilled in the art, may be used.

In a preferred embodiment of the present invention, the thickness of the removable pressure sensitive adhesive layer is 50 μm, and the removable pressure sensitive adhesive layer can be obtained by one-step curing by adopting the above technical scheme. In another preferred embodiment of the present invention, the thickness of the removable pressure-sensitive adhesive layer is 100 μm, and the above-mentioned preparation process is repeated once to obtain a pressure-sensitive adhesive layer having a thickness of 50 μm, and then the pressure-sensitive adhesive layer having a thickness of 50 μm is attached to the previously obtained pressure-sensitive adhesive layer to obtain a removable pressure-sensitive adhesive layer having a thickness of 100 μm. In another preferred embodiment of the present invention, the thickness of the removable pressure-sensitive adhesive layer is 200 μm, and by repeating the above-mentioned preparation process three times, three sets of pressure-sensitive adhesive layers each having a thickness of 50 μm are obtained and then laminated with the previously obtained pressure-sensitive adhesive layer having a thickness of 50 μm to obtain a removable pressure-sensitive adhesive layer having a thickness of 200 μm.

After the removable pressure-sensitive adhesive layer with the release material compounded on one surface is obtained, the first pressure-sensitive adhesive layer with the release material compounded on one surface is attached to one surface of the foam layer, then the second pressure-sensitive adhesive layer with the release material compounded on one surface is attached to the other surface of the foam layer, the release material on the second pressure-sensitive adhesive layer is removed, and then the foam double-sided adhesive tape is rolled to obtain the foam double-sided adhesive tape; at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer.

In a preferred embodiment of the present invention, the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer; according to the invention, a first pressure-sensitive adhesive layer with one surface compounded with a release material is attached to one surface of a foam layer, then a second pressure-sensitive adhesive layer with one surface compounded with the release material is attached to the other surface of the foam layer, the release material on the second pressure-sensitive adhesive layer is removed, and then the foam double-sided adhesive tape is rolled to obtain the foam double-sided adhesive tape.

In the invention, the preferable preparation method of the first pressure-sensitive adhesive layer with the release material compounded on one surface is as follows:

diluting acrylic acid glue with a solvent until the viscosity is 1000 cps-5000 cps, then coating the acrylic acid glue on a heavy release profile of a release material, and drying the acrylic acid glue by an oven to obtain a first pressure-sensitive adhesive layer with one surface compounded with the release material;

more preferably:

and (3) diluting the acrylic glue with a solvent until the viscosity is 2000 cps-4000 cps, then coating the acrylic glue on a heavy release surface of a release material, and drying the acrylic glue in an oven to obtain the first pressure-sensitive adhesive layer with one surface compounded with the release material.

In the present invention, the foam double-sided tape preferably further comprises:

the film layer is arranged between the foam layer and the first pressure-sensitive adhesive layer; the first pressure-sensitive adhesive layer is attached to one surface of the thin film layer, provided with the foam layer of the thin film layer. In the present invention, the thin film layer is the same as that described in the above technical solution, and is not described herein again.

With above-mentioned first pressure sensitive adhesive layer laminating in the thin layer one of the cotton layer of bubble that is provided with the thin layer, preferably still include:

and carrying out corona treatment on one surface of the film layer of the foam layer provided with the film layer. In the present invention, the corona treatment is a technical solution for improving surface adhesion well known to those skilled in the art, and the present invention is not particularly limited thereto.

In the present invention, before the foam layer is attached, it is preferable that the foam layer further includes:

and (3) performing primary coating treatment on the surface to be adhered of the foam layer.

In the present invention, the process of the priming treatment is preferably specifically:

and diluting the bottom coating agent by using a solvent, coating the diluted bottom coating agent on the foam layer, drying and rolling to finish the bottom coating treatment process. The primer is not particularly limited, the bonding force between the removable pressure-sensitive adhesive layer and the foam layer can be enhanced, and the foam adhesive is not subjected to interlayer separation in the using process; such as acrylic polymers that can be copolymerized with acrylamide or other amine-containing alkenyl compounds well known to those skilled in the art. In the present invention, the thickness of the undercoating treatment is preferably 0.5 to 3 μm, more preferably 1 μm. According to the invention, the foam layer is subjected to primary coating treatment, so that the high interlayer bonding force between the foam layer and the removable pressure-sensitive adhesive layer is ensured, and interlayer separation cannot occur in the using process.

According to the invention, the second adhesive pressure-sensitive adhesive layer with one surface compounded with the release material is attached to the other surface of the foam layer, and the release material on the second adhesive pressure-sensitive adhesive layer is removed and then wound to obtain the foam double-sided adhesive tape.

The invention provides a foam double-sided tape, which comprises: a release material; the first pressure-sensitive adhesive layer is compounded on the release material; the foam layer is compounded on the first pressure-sensitive adhesive layer; the second pressure-sensitive adhesive layer is compounded on the foam layer; at least one of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is a removable pressure-sensitive adhesive layer; the removable pressure-sensitive adhesive layer is prepared from the following raw materials: 40 to 60 parts by weight of a thermoplastic elastomer; 40-60 parts of tackifying resin; 10-20 parts of reinforcing agent; 10-25 parts by weight of a softener; 0.2 to 5 weight portions of antioxidant; 0.1 to 5 parts by weight of a filler. Compared with the prior art, the foam double-sided adhesive tape provided by the invention adopts a specific structure, realizes good interaction, fully exerts excellent stress buffering performance and interface filling performance of a foam layer on one hand, and improves bonding performance and endows a product with a tensile removable characteristic through a removable pressure-sensitive adhesive layer with specific content of components on the other hand; the foam double-sided tape provided by the invention has excellent bonding performance, ring-testing resistance, buffering performance, shading performance and shearing resistance, has the characteristics of being removable in stretching and easy to rework, and is particularly suitable for assembling large-size liquid crystal display modules. Experimental results show that the foam double-sided adhesive tape provided by the invention has good adhesiveness, high adhesive force on various surfaces such as glass, PC, stainless steel, ABS and the like, long-term stable adhesion, good curved surface resistance and anti-warping property, and good die cutting property; the adhesive has high initial adhesion and peeling force, high cohesive energy and excellent reworking performance, and can be removed from various surfaces without traces by simple lateral stretching; meanwhile, the liquid crystal display panel has good interface filling performance, so that the pasting interface has a good light blocking effect, is excellent in shading performance, and is particularly suitable for module assembly of large-size liquid crystal display equipment.

In addition, the preparation method provided by the invention can ensure that each layer has higher interlayer binding force, so that interlayer separation cannot occur in the manufacturing and subsequent product use processes; and the process is simple, easy to operate and suitable for large-scale industrial production.

To further illustrate the present invention, the following examples are provided for illustration. The starting materials used in the following examples of the present invention are all commercially available products.