CN114250042B

CN114250042B - Electron beam treated anti-warp pressure sensitive adhesive tape and application thereof

Info

Publication number: CN114250042B
Application number: CN202011019754.3A
Authority: CN
Inventors: 檀梅; 阮明珠; 陆枫; G·马茨
Original assignee: Tesa SE
Current assignee: Tesa SE
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2024-03-26
Anticipated expiration: 2040-09-24
Also published as: CN114250042A

Abstract

The invention relates to an electron beam treated anti-warp pressure sensitive adhesive tape and application thereof. Specifically, disclosed is a pressure-sensitive adhesive tape which can realize excellent warp resistance, adhesive property, cohesive property and quick adhesion at a remarkably thin thickness without foaming and without using microspheres. The anti-warp pressure-sensitive adhesive tape is particularly suitable for bonding irregularly shaped surfaces (e.g., curved surfaces).

Description

Electron beam treated anti-warp pressure sensitive adhesive tape and application thereof

Technical Field

The invention relates to the chemical field, in particular to an electron beam treated anti-tilting pressure sensitive adhesive tape and application thereof.

Background

Although various adhesive tapes exist in the prior art, with the increasing complexity of the surface shape of the substrates to be bonded, significantly higher demands are placed on the adhesion and anti-lifting (AR) properties of the adhesive tapes.

CN109666418A discloses an adhesive composition for forming an adhesive tape by electron beam treatment comprising a pressure sensitive adhesive tape of microspheres, but the AR performance of the adhesive tape is still not very ideal and it is difficult to meet the market demand.

Based on this, there is an urgent need in the art to develop a pressure-sensitive adhesive tape having both excellent adhesion and AR properties.

Disclosure of Invention

The object of the present invention is to provide a pressure-sensitive adhesive tape having both excellent adhesion and AR properties, which also has the characteristics of high cohesion and rapid adhesion.

In a first aspect of the present invention, there is provided a warp-resistant pressure-sensitive adhesive tape comprising at least one layer of an adhesive composition having a thickness of 3 to 150 μm.

In another preferred embodiment, the adhesive composition layer has a thickness of 3 to 50 μm.

In another preferred embodiment, the anti-warp pressure sensitive adhesive tape comprises a layer of adhesive composition.

In another preferred example, the anti-warp pressure-sensitive adhesive tape comprises:

1) A first adhesive composition layer;

2) An intermediate substrate layer; and

3) A second adhesive composition layer;

the intermediate substrate layer is positioned between the first adhesive composition layer and the second adhesive composition layer;

the thickness of the first adhesive composition layer and the second adhesive composition layer are the same or different and are independently 3-80 μm.

In another preferred embodiment, the thickness of the intermediate substrate layer is 0.5-100 μm.

In another preferred embodiment, the adhesive composition layer is prepared by coating, drying and electron beam treatment of a self-adhesive composition consisting of:

a) Based on vinylaromatic block copolymers;

b) A tackifying resin;

c) An antioxidant; and

d) An organic solvent.

In another preferred embodiment, the thickness of the first adhesive composition layer is 3-50 μm; and/or

The thickness of the second adhesive composition layer is 3-50 μm.

In another preferred embodiment, the adhesive composition layer has a density of 800-1500kg/m ³ 。

In another preferred embodiment, the lower limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 3. 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16.

In another preferred embodiment, the lower limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 3. 4, 5, 6, 7, 8, 9, 10.

In another preferred embodiment, the lower limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 3. 4, 5, 6, 7.

In another preferred embodiment, the upper limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 10. 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 78, 79, 80, 81, 82, 83, 84 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150.

In another preferred embodiment, the upper limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 10. 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75.

In another preferred embodiment, the upper limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 10. 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50.

In another preferred embodiment, the upper limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 10. 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40.

In another preferred embodiment, the upper limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 10. 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30.

In another preferred embodiment, the upper limit (unit: μm) of the thickness of the adhesive composition layer is selected from the group consisting of: 10. 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25.

In another preferred embodiment, the two outer surfaces of the AR pressure sensitive adhesive tapes each optionally contain a release film.

In another preferred embodiment, the release film is made of a material selected from the group consisting of: PET, glassine paper and PE composite paper.

In another preferred embodiment, the thickness of the release film is 20-200 μm, preferably 30-100 μm.

In another preferred embodiment, the AR pressure-sensitive adhesive tape comprises a layer of adhesive composition and release films on either side of the layer of adhesive composition.

In another preferred example, the AR pressure sensitive adhesive tape sequentially comprises:

0) A first release film;

1) A first adhesive composition layer;

2) An intermediate substrate layer;

3) A second adhesive composition layer; and

4) And a second release film.

In another preferred embodiment, the thickness of the intermediate substrate layer is 1-60um, preferably 2-40um.

In another preferred embodiment, the material of the intermediate substrate layer is selected from the group consisting of: PET, PVC, paper (e.g., bao Mianzhi tissue paper), nonwoven, PI, PE, PP, PU.

In another preferred embodiment, the thickness of the first adhesive composition layer is in the same range as the thickness of the adhesive composition layer.

In another preferred embodiment, the thickness of the second adhesive composition layer is in the same range as the thickness of the adhesive composition layer.

In another preferred embodiment, the material and thickness of the first release film and the material and thickness of the second release film are the same as the material and thickness range of the release film.

In another preferred embodiment, the vinylaromatic-based block copolymer has the following features:

1) Comprising at least one polymer block A formed mainly by polymerization of vinylaromatic compounds;

2) And at least one polymer block B formed mainly by polymerization of conjugated dienes, wherein the proportion of 1, 2-bonded conjugated dienes in the B block is less than 30% by weight, preferably less than 20% by weight.

In another preferred embodiment, the vinylaromatic block copolymer is ase:Sub>A mixture of linear block copolymers, for example in particular ase:Sub>A mixture of diblock copolymers (ase:Sub>A-B) and triblock copolymers (ase:Sub>A-B-ase:Sub>A), wherein the vinylaromatic block copolymer preferably has ase:Sub>A content of diblock copolymers of from 30 to 60% by weight, preferably from 40 to 60% by weight, for example from more than 51.5 to 55% by weight.

In another preferred embodiment, the vinyl aromatic block copolymer is a block copolymer of a monomer a selected from the group a and a monomer B selected from the group B, the group a being selected from the group consisting of: styrene, alpha-methylstyrene, other styrene derivatives, or combinations thereof, said group B being selected from the group consisting of: butadiene, isoprene, ethylbutadiene, phenylbutadiene, pentadiene, ethylhexadiene, dimethylbutadiene, α -farnesene, β -farnesene, or combinations thereof.

In another preferred example, in the vinyl aromatic block copolymer, the monomer a is polymerized to obtain a block a, the monomer B is polymerized to obtain a block B, and the vinyl aromatic block copolymer has a structure selected from the group consisting of: a-B-A, A-B, or a combination thereof.

In another preferred embodiment, the vinylaromatic block copolymer has from 10 to 85wt% diblock, preferably from 15 to 80wt%.

In another preferred embodiment, the vinyl aromatic block copolymer has a content of block A of from 10 to 60% by weight, preferably from 20 to 50% by weight, more preferably from 30 to 40% by weight.

In another preferred embodiment, the proportion of 1, 2-bonded conjugated diene in the block B of the vinylaromatic block copolymer is from 5 to 30% by weight, preferably from 8 to 20% by weight, more preferably from 10 to 15% by weight.

In another preferred embodiment, the tackifying resin is selected from the group consisting of: solid alpha-pinene, beta-pinene, delta-limonene, or combinations thereof.

In another preferred embodiment, the antioxidant is selected from the group consisting of: irganox168, irganox1010, irganox1076, or a combination thereof.

In another preferred embodiment, the organic solvent is selected from the group consisting of: methylcyclohexane, gasoline, toluene, acetone, ethyl acetate, petroleum ether, or combinations thereof.

In another preferred embodiment, the self-adhesive composition consists of:

a) 40 to 60 parts by weight (preferably 45 to 55 parts by weight, more preferably 48 to 53 parts by weight) based on the vinylaromatic block copolymer;

b) 40-60 parts by weight of tackifying resin (preferably 45-55 parts by weight, more preferably 48-52 parts by weight);

c) 0.5 to 3 parts by weight of an antioxidant (preferably 0.7 to 2 parts by weight, more preferably 0.9 to 1.5 parts by weight); and

d) 100 to 300 parts by weight of an organic solvent (preferably 120 to 280 parts by weight, more preferably 140 to 260 parts by weight).

In another preferred embodiment, the drying is performed at 80-150 ℃, preferably 90-120 ℃, more preferably 95-110 ℃.

In another preferred embodiment, the drying treatment time is 5-30min, preferably 10-25min, more preferably 12-20min.

In another preferred embodiment, the electron beam treatment is performed with an acceleration voltage of 100-180keV, preferably 120-160keV, more preferably 140-160keV.

In another preferred embodiment, the electron beam treatment is performed at a dose of 60-150kGy, preferably 70-140kGy, more preferably 80-130kGy, most preferably 100kGy.

In another preferred embodiment, the AR pressure sensitive adhesive tape is unfoamed.

In another preferred embodiment, the thickness of the first adhesive composition layer is 3-40 μm (preferably 4-30 μm, more preferably 5-25 μm); and/or

The thickness of the second adhesive composition layer is 3 to 40 μm (preferably 4 to 30 μm, more preferably 5 to 25 μm).

In another preferred embodiment, the adhesive composition layer has a density of 850-1200kg/m ³ Preferably 900-1100kg/m ³ 。

In a second aspect of the invention, there is provided an adhesive assembly comprising:

i) A first component;

ii) the anti-lifting pressure sensitive adhesive tape according to the first aspect of the invention;

iii) A second component;

the warp-resistant pressure-sensitive adhesive tape is used for bonding the first member and the second member.

In another preferred example, the surface to be bonded of the first member is an irregularly shaped surface; and/or

The surface to be bonded of the second member is an irregularly shaped surface.

In another preferred embodiment, the materials of the first and second parts may be the same or different, each independently selected from the group including but not limited to: PC, PI, steel.

In another preferred embodiment, the material of the first part is selected from the group consisting of: PVC, PET, aluminum.

In another preferred embodiment, the material of the second part is selected from the group consisting of: PBT, PEEK, PP.

In another preferred embodiment, the irregularly shaped surface is selected from the group consisting of, but not limited to: curved surface, 90 degrees right angle bending surface.

In another preferred embodiment, the surface to be bonded of the first component and/or the surface to be bonded of the second component is independently a regular plane.

In another preferred embodiment, the regular planar surfaces are optionally subjected to an internal or external force, respectively, after being adhered by the anti-warp pressure sensitive adhesive tape.

In another preferred embodiment, the first component and the second component are each independently selected from the group consisting of: electronic components (e.g., cell phone components, antenna assemblies, PCBs, FPCs (flexible circuit boards), electronics housings (e.g., cell phone housings, cell phone frames, cell phone rear covers).

It is understood that within the scope of the present invention, the above-described technical features of the present invention and technical features specifically described below (e.g., in the examples) may be combined with each other to constitute new or preferred technical solutions. And are limited to a space, and are not described in detail herein.

Drawings

FIG. 1 is a schematic representation of the static peel test AR performance of the present invention.

FIG. 2 is a schematic diagram of an edge wrapping (AR) test of the present invention.

FIG. 3 is a schematic diagram of the name plate (AR) test of the present invention.

FIG. 4 is a schematic view of a single layer adhesive tape of the present invention, wherein 1 is an adhesive composition layer and 2 and 3 are release films.

FIG. 5 is a schematic view of a double-layered adhesive tape of the present invention, wherein 1 is an adhesive composition layer, 2 is a release film, and 3 is an intermediate substrate layer.

FIG. 6 is a schematic illustration of an adhesive performance test of the present invention.

FIG. 7 is a schematic representation of the cohesive performance test of the present invention.

Detailed Description

The present inventors have conducted long and intensive studies to obtain an ultra-thin pressure-sensitive adhesive tape having excellent AR properties, which also has excellent adhesion, high cohesion and rapid adhesion characteristics, by optimizing the formulation of the adhesive composition (without using foaming and/or microspheres) and optimizing the electron beam treatment process. On this basis, the inventors completed the present invention.

Electron beam processing

A system from ELECTRON CROSSLINKING AB (Halmstad, sweden) may be used with an acceleration voltage of 150keV (matching the desired penetration depth and product density if required) and a suitable dose of e.g. 10 to 120kGy. Typically, the layer of self-adhesive composition is subjected to electron irradiation from both sides (i.e. symmetrically) to ensure uniform curing. This is advantageous in particular in the case of a layer of self-adhesive composition to be irradiated having a relatively large thickness. For example, in the case of a thin sample having a thickness of 50 μm, one-sided irradiation may be performed. Preferably, the liner is removed from the appropriate side prior to irradiation, in particular in order to avoid radiation losses and liner damage. The effect of the latter may in particular be that the liner can no longer be pulled off from the layer of self-adhesive composition after irradiation. The irradiation operation may be accomplished in-line or in one step during the preparation process, with appropriate technical design.

The invention therefore also relates to a process for preparing a pressure-sensitive adhesive tape as defined above, in which a self-adhesive composition is processed from solution into layers, and the layers are optionally subjected to electron irradiation. The method can be performed without using a crosslinking accelerator, which reduces the production cost and complexity of the pressure sensitive tape of the present invention.

AR Property (anti-roll Property)

When the tape is applied to a curved surface (i.e., curved surface), there is a need for the tape to resist lifting for the purpose of sufficient adhesion. Since the curved surface is intended to return to a flat surface (a low energy state), there is an internal force inside the adhesive tape (i.e., an internal force returning from the curved surface to the flat surface) to debond the adhesive tape from the surface of the substrate to be bonded, which requires the adhesive tape to have excellent anti-lifting properties, otherwise the adhesive tape will not bond the substrate to be bonded for a long period of time.

The anti-warp properties of the tape are often required in the bonding of curved surfaces, such as curved screens, flexible circuit board (FPC) bonding, antenna bonding, etc.

Note that the anti-lifting property is different from peel strength (peel adhesion), so that simple high adhesion is not sufficient.

AR performance test method

The method comprises the following steps: static stripping (Static peel)

The test schematic is shown in fig. 1, and the relevant test parameters are shown in table 1:

TABLE 1

The adhesive tape was cut into strips 20mm wide and then attached to a 25 μm transparent PET reinforcing film to prepare test pieces, which were uniformly attached to a PC board, and rolled 5 back and forth at a speed of 10m/min by a 4Kg steel roll. The PC board was then fixed in an oven at 70 degrees celsius with the tape facing down. After the tape head is perforated, a weight of 50 g is hung, the position of the tape head at the beginning of the test is recorded, and the sliding distance of the tape is recorded after 4 hours. The shorter the distance of the slip, the better the static peel test effect of the tape.

Determination criteria: the sliding distance is less than 5mm and is grade A, the sliding distance is grade B between 5 and 15 mm, and the sliding distance is grade C when more than 15 mm.

The second method is as follows: edge wrapping test (Edge pointing)

The test schematic is shown in fig. 2, and the relevant test parameters are shown in table 2:

TABLE 2

The tape was applied to 125 μm PI film, cut to 100 x 34.4mm, then 100mm x 4.4mm was applied to PC board, and the remaining tape portion was folded and applied to the side and the other side of PC after the rolling conditions as indicated above. The rest part area is 100mm 30mm, and then the rest part area is rolled back and forth for 5 back and forth through a rubber roller of 2 Kg. The prepared sample was placed in an oven at 85 ℃ and 85% rh, taking care that the tape and the portion of the PC board adhered did not contact the oven. And after three days, observing whether the attached adhesive tape is tilted, and if not, passing.

And a third method: nameplate test (Name plate)

The test schematic is shown in fig. 3, and the relevant test parameters are shown in table 3:

TABLE 3 Table 3

The tape was attached to 150mm x 20mm aluminum plate and the excess was trimmed. The parts were attached to the middle part of the PC board, rolled under the rolling conditions shown above, and allowed to stand at room temperature for one day. And then secured to the clamp as shown in fig. 3. The bending included angle of the two sides of the clamp is 30 degrees. The height of the aluminum plate cocked was measured after one day at 60 ℃,90% rh. The smaller the tilting height is, the better the bending-resistant effect of the adhesive tape is.

Determination criteria: the tilting height is less than 10 mm and is grade A; between 10 and 20 millimeters, class B; a rating of C greater than 20 mm.

Regarding the above three test methods, the test standard is gradually improved from the first method to the third method, and the adhesive tape passing through the first method, the second method and the third method simultaneously has excellent AR performance.

Pressure-sensitive adhesive tape

The vinyl aromatic based block copolymers can be crosslinked in the elastomeric block by electron beam. The proportion of 1, 2-bonded diene in the elastomer block is currently greater than 30% by weight, since the 1, 2-bonded diene units (referred to as vinyl groups) are known to the person skilled in the art to be more reactive. Thus, it is generally difficult to induce crosslinking of elastomeric blocks having a low proportion of 1, 2-bonded dienes.

The vinyl aromatic-based block copolymer:

containing at least one polymer block A formed mainly by polymerization of vinylaromatic compounds, and

at the same time, at least one polymer block B formed mainly by polymerization of conjugated dienes, wherein the proportion of 1, 2-bonded conjugated dienes in the B blocks is less than 30% by weight, preferably less than 20% by weight (determinable, for example, by 1H NMR).

According to the invention, what is generally meant by a self-adhesive composition "based on a vinylaromatic block copolymer" is that the polymer assumes the function of the elastomeric component in the self-adhesive composition. Preferably, the polymer is provided as the sole elastomeric component in the self-adhesive composition, or in any case to the extent of at least 50% by weight, based on the total content of all elastomeric components.

According to the invention, the polymer block A of the vinylaromatic block copolymer is formed mainly by polymerization of vinylaromatic compounds. This means that the block A generally originates from the polymerization in which more than 50% by weight of the monomers used are vinylaromatic compounds, which means that the proportion of vinylaromatic compounds in the polymerization is more than 50% by weight. Preferably, the polymer block A generally derives from the polymerization of the vinyl aromatic compound alone, the monomers used therein.

According to the invention, the polymer block B of the vinylaromatic block copolymer is formed mainly by polymerization of conjugated dienes. This means that the block B generally results from a polymerization in which more than 50% by weight of the monomers used are conjugated dienes, which means that the proportion of conjugated dienes in the polymerization is more than 50% by weight. Preferably, the polymer block B results from the polymerization in which the monomers used are only conjugated dienes.

In addition, the proportion of 1, 2-bonded conjugated dienes in the B blocks is less than 30% by weight, preferably less than 20% by weight, more preferably less than 15% by weight and in particular about 10% by weight. The proportion of 1, 2-bonded conjugated diene in the B block means the weight proportion of conjugated diene polymerized by 1,2 addition (as opposed to 1,4 addition), based on the total monomer composition used to prepare the polymer block B. The 1,2 addition of the conjugated diene produces vinyl side groups in the polymer block B, while the 1,4 addition of the conjugated diene produces vinyl functional groups in the backbone of the polymer block B. Thus, 1,2 addition of a conjugated diene means that the diene functionality is polymerized at the C1 and C2 or at the C3 and C4 positions (e.g., in the case of isoprene as the conjugated diene), rather than the 1,4 addition of a conjugated diene in which the diene functionality is polymerized at the C1 and C4 positions.

The self-adhesive composition is a Pressure Sensitive Adhesive (PSA). Within the scope of this document, the terms "self-adhesive" and "pressure-sensitive adhesive" are used synonymously in this respect.

Pressure-sensitive adhesive compositions are in particular those polymer compositions which, if appropriate by suitable addition of further components, for example tackifying resins, are permanently tacky and adhesive at the use temperature (unless otherwise specified, at room temperature) and adhere on contact with a plurality of surfaces, and in particular adhere immediately (have a so-called "tack" [ tack or touch-tack ]). Even at the use temperature, it is capable of sufficiently wetting the substrate to be bonded without activation by solvent or heat (but typically by the influence of greater or lesser pressure) so that a sufficient adhesive interaction is formed between the composition and the substrate. Essential influencing parameters in this respect include pressure and contact time. The excellent properties of pressure-sensitive adhesive compositions are derived in particular from their viscoelastic properties. For example, weakly or strongly adhering adhesive compositions can be prepared; and adhesive compositions that can be bonded only once and permanently so that the bond does not separate without damaging the adhesive and/or the substrate, or can be easily separated again and, if appropriate, the bonded adhesive composition can be repeated.

The pressure-sensitive adhesive compositions can in principle be prepared based on polymers of different chemical nature. Pressure sensitive adhesive properties are affected by the following factors: including the nature and proportion of the monomers used in the polymerization of the underlying polymer of the pressure sensitive adhesive composition, its average molar mass and molar mass distribution, and the nature and amount of additives of the pressure sensitive adhesive composition such as tackifying resins, plasticizers, and the like.

In order to achieve viscoelastic properties, the monomers on which the underlying polymer of the pressure-sensitive adhesive composition is based and any other components present in the pressure-sensitive adhesive composition are specifically selected such that the glass transition temperature of the pressure-sensitive adhesive composition (according to DIN 53765) is below the use temperature (i.e., typically below room temperature).

In some cases, it may be advantageous to expand and/or alter the temperature range at which the polymer composition has pressure sensitive adhesive properties by suitable cohesive enhancing means, such as crosslinking reactions (formation of bridges between macromolecules to form linkages). Thus, the application range of the pressure-sensitive adhesive composition can be optimized by setting between fluidity and cohesion of the composition.

The pressure-sensitive adhesive composition has a permanent pressure-sensitive adhesion at room temperature, i.e. a sufficiently low viscosity and a high touch tack, such that it wets the surface of the corresponding adhesive substrate even at low contact pressures. The bondability of the adhesive composition is based on its adhesive properties, while the re-separability is based on its cohesive properties.

The vinylaromatic block copolymer used is preferably at least one synthetic rubber in the form of ase:Sub>A block copolymer having the structure A-B, A-B-A, (A-B) n, (A-B) n X or (A-B-A) n X,

wherein the method comprises the steps of

The A blocks are independently polymers formed by polymerization of at least one vinylaromatic compound,

the B blocks are independently polymers formed by polymerization of conjugated dienes having from 4 to 18 carbon atoms,

x is a radical of a coupling reagent or initiator, and

-n is an integer not less than 2.

More preferably, all of the synthetic rubbers in the layer of the self-adhesive composition of the invention are block copolymers having the structure A-B, A-B-A, (A-B) n, (A-B) n X or (A-B-A) n X as described above. Thus, the self-adhesive composition layer of the present invention may further comprise a mixture of various block copolymers having the above-described structure.

Thus, suitable block copolymers (vinyl aromatic block copolymers) comprise one or more rubbery blocks B (soft blocks) and one or more glassy blocks a (hard blocks). More preferably, at least one of the synthetic rubbers in the layer of the self-adhesive composition of the invention is ase:Sub>A block copolymer having ase:Sub>A structure of A-B, A-B-A, (A-B) 2X, (A-B) 3X or (A-B) 4X, wherein the above meanings apply to A, B and X. Most preferably, all the synthetic rubbers in the layer of the self-adhesive composition of the invention are block copolymers having the structure A-B, A-B-A, (A-B) 2X, (A-B) 3X or (A-B) 4X, wherein the above meanings apply to A, B and X. More particularly, the synthetic rubber in the layer of the self-adhesive composition of the present invention is ase:Sub>A mixture of block copolymers having ase:Sub>A structure of A-B, A-B-A, (A-B) 2X, (A-B) 3X or (A-B) 4X, preferably comprising at least diblock copolymer A-B and/or triblock copolymer A-B-A and/or (A-B) 2X.

Also advantageous are mixtures of diblock and triblock copolymers and (A-B) n or (A-B) n X block copolymers, where n is not less than 3.

Also advantageous are mixtures of diblock and multiblock copolymers and (A-B) n or (A-B) n X block copolymers, where n is not less than 3.

Particularly preferred are mixtures of linear block copolymers, for example in particular mixtures of diblock copolymers (A-B) and triblock copolymers (A-B-A). For example, two vinyl aromatic block copolymers having different weight ratios of diblock copolymer (A-B) and triblock copolymer (A-B-A) may be used. More preferably, the self-adhesive composition of the invention is based on styrene block copolymers; for example, the block copolymer of the self-adhesive composition has polystyrene end blocks.

Thus, the vinylaromatic block copolymers used may be, for example, a combination of diblock copolymers A-B with the other block copolymers mentioned. The ratio of diblock copolymer may be used to adjust the adaptive properties of the self-adhesive composition and its adhesive strength. Preferably, the content of diblock copolymer of the vinylaromatic block copolymer used according to the invention is from 0% to 70% by weight, more preferably from 15% to 65% by weight, more preferably from 30% to 60% by weight, and in particular from 40% to 60% by weight, for example from greater than 51.5% to 55% by weight. The higher proportion of diblock copolymer in the vinylaromatic block copolymer results in a significant decrease in the cohesion of the adhesive composition.

Commercially available block copolymer types typically have a combination of polymers of different structures. For example, kraton D1101 according to the manufacturer is nominally a linear polystyrene-polybutadiene triblock copolymer (The Global Connection forPolymer and Compound Solution-Product and Application Guide, kratonPerformance Polymers, 2011) containing 16 wt% diblock copolymer. In contrast, kraton D1118 is a different polystyrene-polybutadiene block copolymer containing 78 wt.% of diblock copolymer.

The block copolymers resulting from the A and B blocks may contain the same or different B blocks. The block copolymer may have ase:Sub>A linear ase:Sub>A-B-ase:Sub>A structure. Radial forms of block copolymers and radial and linear multiblock copolymers may also be used. The other component present may be an a-B diblock copolymer. All of the above polymers may be used alone or in combination with each other.

In the vinylaromatic block copolymers used according to the invention, in particular for example styrene block copolymers, the proportion of the vinylaromatic compounds, for example in particular polystyrene, is preferably at least 12% by weight, more preferably at least 18% by weight, and particularly preferably at least 25% by weight, and likewise preferably at most 45% by weight, and more preferably at most 35% by weight.

In addition to the preferred polystyrene blocks, the vinylaromatic compounds used may also be polymer blocks based on other aromatic-containing homopolymers and copolymers, preferably C8 to C12 aromatics, having a glass transition temperature of greater than 75℃such as, for example, alpha-methylstyrene-containing aromatic blocks. In addition, the same or different A blocks may also be present.

Preferably, the vinyl aromatic compounds used to form the a block include styrene, alpha-methylstyrene and/or other styrene derivatives. Thus, the a block may be in the form of a homopolymer or a copolymer. More preferably, the a block is polystyrene.

Preferred conjugated dienes as monomers for the soft block B are in particular selected from butadiene, isoprene, ethylbutadiene, phenylbutadiene, pentadiene, hexadiene, ethylhexadiene, dimethylbutadiene, α -farnesene and β -farnesene, and any mixtures of these monomers. The B block may also be in the form of a homopolymer or copolymer. Butadiene, isoprene or mixtures thereof are particularly preferred. In particular, butadiene is used. Polybutadiene has better aging characteristics than polyisoprene.

The a blocks in the context of the present invention are also referred to as "hard blocks". Accordingly, the B block is also referred to as a "soft block" or "elastomeric block". This is reflected in the invention in the selection of the blocks according to their glass transition temperature (at least 25℃for the A blocks, in particular at least 50℃and not more than 25℃for the B blocks, preferably not more than-25℃and in particular not more than-50 ℃).

In general, even when no vinylaromatic block copolymer is involved, the block structure as described above can be described as a "hard block-soft block structure".

The proportion of vinylaromatic block copolymers, such as in particular styrene block copolymers, is in total at least 35% by weight. Too low a proportion of vinylaromatic block copolymer results in a relatively low cohesion of the pressure-sensitive adhesive composition, preferably based on the entire self-adhesive composition layer.

The maximum proportion of vinylaromatic block copolymers, such as in particular styrene block copolymers, is in total at most 75% by weight, preferably at most 65% by weight, further preferably at most 55% by weight, based on the total self-adhesive composition. Too high a proportion of vinylaromatic block copolymer in turn results in little or no pressure sensitive adhesion in the pressure sensitive adhesive composition.

Thus, the proportion of vinylaromatic block copolymers (e.g. in particular styrene block copolymers) is preferably at least 35% by weight in total and at the same time at most 75% by weight, more preferably at most 65% by weight, most preferably at most 55% by weight, in particular based on the total self-adhesive composition.

Pressure sensitive adhesion of the self-adhesive composition can be achieved by the addition of a tackifying resin that is miscible with the elastomer. In addition to the at least one vinylaromatic block copolymer, the self-adhesive composition generally comprises at least one tackifying resin in order to increase the adhesion in a desired manner. The tackifying resin should be compatible with the elastomeric blocks of the block copolymer.

As generally understood by those skilled in the art, "tackifying resin" is understood to mean a low molecular weight oligomeric or polymeric resin that increases the adhesion (tack, inherent tackiness) of the pressure sensitive adhesive composition as compared to an otherwise identical pressure sensitive adhesive composition without any tackifying resin.

Preferably, the tackifying resin selected to the extent of at least 75% by weight (based on total resin content) is a resin having a DACP (diacetone alcohol cloud point) of greater than 0 ℃, preferably greater than 10 ℃, especially greater than 30 ℃, and a softening temperature (rings and spheres) of not less than 70 ℃, preferably not less than 100 ℃. More preferably, the tackifying resins mentioned at the same time have a DACP value of not more than 45 ℃ if no isoprene block is present in the elastomeric phase, or of not more than 60 ℃ if an isoprene block is present in the elastomeric phase. More preferably, the softening temperature of the mentioned tackifying resin is not more than 150 ℃. More preferably, the tackifying resin comprises at least 75 wt% (based on total resin content) of a hydrocarbon resin or terpene resin or mixtures thereof.

Tackifiers which can be advantageously used in pressure-sensitive adhesive compositions have been found to be particularly nonpolar hydrocarbon resins, such as hydrogenated and unhydrogenated polymers of dicyclopentadiene, unhydrogenated, partially, selectively or fully hydrogenated hydrocarbon resins based on C5, C5/C9 or C9 monomer streams, and polyterpene resins based on alpha-pinene and/or beta-pinene and/or delta-limonene. The above tackifying resins may be used alone or in combination. A room temperature solid resin or a liquid resin may be used. Tackifying resins in hydrogenated or non-hydrogenated form (which also contain oxygen) may optionally and preferably be used in the adhesive composition in a maximum proportion of up to 25% based on the total mass of the resin, for example rosin and/or rosin esters and/or terpene-phenolic resins.

Hydrogenated hydrocarbon resins are particularly suitable for use in the present invention because the absence of double bonds means that crosslinking cannot be broken.

However, in addition, unhydrogenated resins can also be used, especially when crosslinking accelerators such as multifunctional acrylates are used. It is particularly preferred to use terpene resins based on α -pinene (Piccolyte a series from Pinova, dercolyte a series from DRT) because these ensure very high adhesion in addition to high cohesion even at high temperatures. However, other unhydrogenated hydrocarbon resins, unhydrogenated analogs of the above hydrogenated resins can also be used.

In a preferred embodiment, from 20 to 60 wt% of at least one tackifying resin is present in the self-adhesive composition layer, based on the total weight of the self-adhesive composition layer, preferably from 30 to 50 wt% of at least one tackifying resin, based on the total weight of the self-adhesive composition layer.

To stabilize pressure sensitive adhesives against aging, primary antioxidants such as sterically hindered phenols, secondary (secondary) antioxidants such as phosphites or thioethers, and/or carbon radical scavengers are generally added. Since the vinylaromatic block copolymers used according to the invention have a small proportion of 1, 2-bonded conjugated dienes in the B blocks, the pressure-sensitive adhesive tapes according to the invention are relatively stable to aging even without the addition of aging stabilizers. However, the aging stability can be further improved by adding an aging stabilizer. However, it should be considered that aging stabilizers increase process complexity and have a tendency to migrate or have a plasticizing effect.

The release liner of the present invention preferably has a good balance between strength and flexibility. First, its strength is to counteract excessive stretching or stretching of the tape during processing and application; secondly, it should also be flexible enough to be able to apply the tape together with the release liner, even in the form of a curve without folds. Preferably, the release liner is additionally dimensionally stable at elevated temperatures. This enables, inter alia, the release liner to be coated directly with the pressure-sensitive adhesive treated by the hot-melt method after the treatment without any disadvantageous changes in the shape of the release liner, which means that such release liners can be coated directly. Such release liners for use on pressure sensitive adhesives are, for example, release liners comprising the following layers:

An external silicone release layer (SR),

a layer (POL) containing in each layer a total of at least 50% by weight of one or more polyolefins, in each case based on the total weight of the layer,

wherein the layer (POL) contains at least 60 wt% polypropylene, based on the total weight of the layer (POL), and

-an outer layer (PER) containing at least 80 wt% of polyethylene, based on the total weight of the layer (PER), wherein the layer (PER) is bonded to the next layer in the release liner structure by means of an adhesive.

Preferably, the release liner is additionally provided with a gripping aid and can be pulled away from the adhesive without difficulty. For example, one or more gripping ears (e.g., made of PET/PE composite or aluminum/PET/PE composite) may optionally be heat welded to the release liner of the present invention. The liner can then be pulled away from the pressure sensitive adhesive without difficulty, without damaging the composite of the grip tab and liner or the layer composite of the liner.

If the diblock content in the elastomeric component is below 50%, it is also possible to obtain a product, in particular a transfer tape, which can be separated again by stretching, substantially without residues from the adhesive joints or from the surface. For the prior art on products which are re-separable by stretching, reference is made to WO2017/064167A1 and the documents cited therein.

Application of

The double-sided adhesive tape can be applied to curved surface lamination, bending surface lamination or plane lamination, and the material always has tilting stress. Such as FPC bonding in the handset, 5G antenna bonding, 3D back cover curved surface bonding, etc.

Compared with the prior art, the invention has the following main advantages:

(1) The pressure-sensitive adhesive tape has excellent adhesive property, AR property, cohesive property and quick adhesive property, is a pressure-sensitive adhesive tape with excellent comprehensive properties, and is particularly suitable for substrates to be adhered in complex shapes;

(2) The pressure-sensitive adhesive tape of the present invention does not require a subsequent curing treatment since a separate crosslinking accelerator is not used;

(3) Compared with the traditional polyacrylate pressure-sensitive adhesive tape with AR performance, the pressure-sensitive adhesive tape has poor adhesive performance on non-polar adherends, and has excellent adhesive performance on polar and non-polar adherends.

(4) Compared with the traditional polyacrylate pressure-sensitive adhesive with AR performance, the adhesive has the capability of rapid wetting, is easy to activate and is beneficial to die cutting processing.

The invention will be further illustrated with reference to specific examples. It is to be understood that these examples are illustrative of the present invention and are not intended to limit the scope of the present invention. The experimental procedures, which do not address the specific conditions in the examples below, are generally carried out under conventional conditions or under conditions recommended by the manufacturer. Percentages and parts are by weight unless otherwise indicated.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In addition, any methods and materials similar or equivalent to those described herein can be used in the methods of the present invention. The preferred methods and materials described herein are presented for illustrative purposes only.

Universal test method

Thickness test:

test instrument: PEACOCK R1-205

Test conditions: 23+ -1deg.C, 50+ -5%

Density testing:

cutting a sample of a certain size (e.g. 10 cm. Times.10 cm, or 100 cm) ² ) The thickness was weighed and measured and the density was calculated by the formula. Density = weight/(thickness x area)

AR Performance: the AR performance of the pressure-sensitive adhesive tape of the present invention was characterized by the three test methods shown above;

adhesive properties: the adhesive properties of the pressure-sensitive adhesive tapes according to the invention were tested as follows:

substrate to be bonded	Steel plate/PE plate (polyethylene plate)
		Bonding area	150mm*20mm
Rolling	4kg,10m/min,5 back and forth
		Reinforced film	38 μm PVC or 25 μm PET
Test conditions	23±1℃，50±5％RH
		Test speed	300mm/min
Test unit	N/cm

The tape was tested immediately after the tape was prepared according to the above table method, three replicates were measured for each sample, and the average was taken.

The specific test process is as follows: after cutting the tape into strips 20mm wide and attaching the strips to a 25 μm transparent PET reinforcing film (38 μm PVC is used as the reinforcing film in the case of a double-sided tape base material tape), test samples were prepared, the test samples were uniformly attached to a steel plate/PE plate, and rolled 5 back and forth at a speed of 10m/min by a 4Kg steel roll. The peel test was then performed with a tensile machine at a speed of 300mm/min, as shown in FIG. 6. Peel values were recorded in N/cm.

High temperature cohesive properties: the cohesive properties of the pressure-sensitive adhesive tapes of the invention were tested as follows:

/>

the tape was sampled according to the above method and then placed in an oven at 90 c for testing, and the time in minutes when the load was dropped was recorded. Three replicates were measured for each sample, taking the median.

The specific test process is as follows: the adhesive tape is cut into strips with the width of 13mm and then is stuck to an aluminum film with the thickness of 50 mu m, two ends of the adhesive tape are trimmed, and the adhesive tape is flatly stuck to the steel plate next to scale marks on the steel plate, wherein the sticking area is 13mm by 20mm. Then, a 2Kg roller was used to roll two back and forth at a speed of 300 mm/min. The prepared sample is hung in a baking oven at 90 ℃ and is tested by loading 1 kg, and the time when the 1 kg weight falls is recorded. As shown in fig. 7.

Aging test of aging resistance：

The samples were left at 40 ℃ for one, three or six months and their aged properties were tested and compared to the initial properties, the ageing resistance was excellent if the test grade was unchanged.

General raw materials

TABLE 4 Table 4

Adhesive composition formulation

The composition of the adhesive composition used in the present invention is shown in Table 5 in parts by weight:

TABLE 5

	R1	R2	R3	R4
					D1101	173	158	218	139
D1118	337	392	382	301
					A115	490	450	400	560
Irganox168	5	3	8	2
					Irganox1010	5	7	2	8

General preparation method

Stage one: solvent and/or melt process preparation

Taking the solvent method as an example, first, 40% by weight of an adhesive solution of the prescribed formulation in each case in petrol/toluene/acetone is prepared. The weight proportions of the dissolved ingredients are each based on the dry weight of the resulting solution. The obtained mixture was then coated with a coating bar on a liner provided with a silicone release agent of a desired layer thickness, and the solvent was evaporated at 100 ℃ for 15min, thereby drying the composition layer.

The procedure of the melting method is described in CN109666418A method V2.

It is understood that in the present invention, the properties of the resulting layers of the composition are comparable in both solvent and melt processes.

Stage two: electron beam processing

Example 1 (A1 without microspheres+E-Beam treatment, A2 without microspheres+E-Beam treatment, A3 with microspheres+E-Beam treatment)

Example A1: the structure shown in fig. 4 was prepared by the above solvent method, 1 being an adhesive layer, 2 and 3 being release films. The adhesive solution adopts R1 and 1000 parts by weight of toluene and 490 parts by weight of petroleum ether as solvents, and the content of R1 is 40wt% based on the total weight of the obtained solution. The double-sided liner material was PET (polyethylene terephthalate) with a thickness of 36 μm and 50. Mu.m. The adhesive solution was coated on one side of the liner, dried to give a self-adhesive composition layer having a thickness of 50 μm, and then the self-adhesive composition layer was treated on one side with electron irradiation. The electron irradiation instrument was ELECTRON CROSSLINKING AB (Halmstad, sweden), the acceleration voltage was 150keV, and the energy was 100kGy. The density of the obtained adhesive tape A1 was 1010kg/m ³ 。

In this embodiment, the release film may be applied before or after application, in this case, a double release film, and only one release film is applied before EB, and the other release film is applied after EB.

Example A2: adhesive solution composition the same as in example A1, a non-irradiated reference sample was also prepared. The thickness is 50 μm. The density of the obtained adhesive tape A2 was 1010kg/m ³ 。

Example A3: samples were also prepared for electron beam treatment of the same parameters after microsphere foaming. The adhesive solution used consisted of: the adhesive solution adopts R1, 1000 parts by weight of toluene and 490 parts by weight of petroleum ether as solvents and 10 parts by weight of foaming microspheres according to the following weight partsThe total weight of the obtained solution was 40wt% of R1 and 10wt% of microspheres. The microsphere foaming method is to foam a layer of self-adhesive composition between two liners in an oven at 150 ℃ for 5min. The thickness of the resulting layer of self-adhesive composition was 50. Mu.m. The thickness of 50 μm is already the lower limit of the thickness of the microsphere foamed adhesive tape, and it is difficult to prepare thinner microsphere foamed adhesive tapes. The density of the obtained adhesive tape A3 was 836kg/m ³ 。

Test of examples A1 to A3

In each case, a static peel test and a binding test (name plate), namely method one and method three, respectively, were performed.

In each case, an edge taping test (i.e., method two) was performed in which the D/S tape was tape (i.e., layer of self-adhesive composition). The testing method comprises the following steps: the test area was 100 x 4.4mm, the length was 100mm, and the PI film with a thickness of 125 μm was attached to a PC board by 90 ° bending. The test environment was 85 ℃, 85% rh, 3 days. Judging the anti-tilting performance according to whether tilting and tilting height.

Judgment standard:

class a: the upper surface and the lower surface of the PI film are not tilted (namely, the upper surface and the lower surface of the PI film are not tilted at all);

b level: the lifting height is less than 2mm (namely, the lifting maximum height of the upper surface and/or the lower surface of the PI film is less than 2 mm);

c level: and (3) fully tilting (namely, no adhesive is connected between the PI film and the PC board).

Also in each case, a high-temperature cohesion test (dimensions of test tape: length 13mm, width 20mm, measuring temperature: 90 ℃, load 1 kg) was carried out by means of a static shear test to test the life cut at a height Wen Jian. The test board is a steel board.

Judgment standard: the duration is 120min, A+ is 90-120min, A is 30-90min, B is 30-90min, and C is <30 min.

Also in each case, peel force adhesion performance tests were carried out. Samples were prepared in the same manner (area 20 mm. Times.15 cm,300mm/min peel speed) and peel force test was performed on steel and PE plates.

Judgment standard: the peel force test was A rated at greater than 8N/cm, B rated at 5-8N/cm, and C rated at less than 5N/cm.

The results are shown in Table 6 below:

TABLE 6

As can be seen from the above, the comprehensive performance of A1 is most excellent. The advantages of electron beam treatment are evident from the comparison of A1 with A2.

Furthermore, the A1 of the present invention has a remarkably excellent combination of properties compared to A3 comprising microspheres and treated with the same electron beam.

As in example A1, tapes of the composition layers of the following thicknesses were prepared and tested for properties, and the results are shown in table 7.

TABLE 7

From table 7 above, it can be seen that: even a very thin adhesive tape has good performance, the requirement is met, namely, the performance of other adhesive tapes cannot meet the AR requirement when the adhesive tape is 30 mu m, but the method provided by the invention can solve the problem, and the ultrathin adhesive tape is endowed with good AR performance.

It should be understood that the performance of the tapes of the present invention using R2, R3 and R4 instead of R1, respectively, is similar to that obtained using R1.

Example 2 (B1 irradiation dose 80kGy, B2 irradiation dose 100kGy, B3 irradiation dose 120 kGy)

In example B1, a structure as shown in FIG. 5 was prepared by the solvent method described above, wherein 1 was a self-adhesive composition layer, a single layer thickness of 13 μm,3 was a base material layer, the base material layer was a PET film 4.5 μm thick, and 2 was a double-sided release film (a release paper was used as a material, and a thickness of 70 μm). The adhesive solution adopts R1 and 1000 weight parts of methylcyclohexane and 490 weight parts of petroleum ether as solvents, and R1 contains, based on the total weight of the obtained solutionThe amount was 40wt%. After the structure shown in FIG. 5 is obtained, electron irradiation is performed on one side on the upper self-adhesive composition layer. The electron irradiation instrument was ELECTRON CROSSLINKING AB (Halmstad, sweden), the acceleration voltage was 150keV, and the energy was 80kGy. The density of the obtained adhesive tape B1 was 1007Kg/m ³ 。

Example B2 was prepared by the solvent method described above, wherein 1 was a self-adhesive composition layer, a single layer thickness of 13 μm,3 was a base material layer, the base material layer was a PET film 4.5 μm thick, and 2 was a double-sided release film (release paper, thickness of 70 μm). The adhesive solution uses R1 and 1000 parts by weight of methylcyclohexane and 490 parts by weight of petroleum ether as solvents, and the content of R1 is 40wt% based on the total weight of the obtained solution. After the structure shown in FIG. 5 is obtained, electron irradiation is performed on one side on the upper self-adhesive composition layer. The electron irradiation instrument was ELECTRON CROSSLINKING AB (Halmstad, sweden), the acceleration voltage was 150keV, and the energy was 100kGy. The density of the obtained adhesive tape B2 was 1007Kg/m ³ . Application of release film was as in example B1.

Example B3 was prepared by the solvent method described above, wherein 1 was a self-adhesive composition layer, a single layer thickness of 13 μm,3 was a base material layer, the base material layer was a PET film 4.5 μm thick, and 2 was a double-sided release film (release paper, thickness of 70 μm). The adhesive solution uses R1 and 1000 parts by weight of methylcyclohexane and 490 parts by weight of petroleum ether as solvents, and the content of R1 is 40wt% based on the total weight of the obtained solution. After the structure shown in FIG. 5 is obtained, electron irradiation is performed on one side on the upper self-adhesive composition layer. The electron irradiation instrument was ELECTRON CROSSLINKING AB (Halmstad, sweden), the acceleration voltage was 150keV, and the energy was 120kGy. The density of the obtained adhesive tape B3 was 1007Kg/m ³ . Application of release film was as in example B1.

In each case, a high temperature cohesion test (dimensions of test tape: length 13mm, width 20mm, measuring temperature: 90 ℃, load 1 kg) was carried out by means of a static shear test to test the life cut at a height of Wen Jian. The test board is a steel board.

Judgment standard: the duration is 120min, the A+ is the duration of 90-120min, the B is the duration of 30-90min, and the C is the duration of <30 min.

The peel force test and edge tapping test (i.e., method two) were likewise passed in each case.

The results are shown in Table 8 below:

TABLE 8

From the above results, it can be seen that the cohesive force of the adhesive tape is enhanced when the electron beam energy is increased. However, when the electron beam energy is too strong, the peel strength and the lifting resistance of the adhesive tape are lowered. Of course, the thickness of the sample in this example is only 30 μm, and the preferred electron beam energies for different thickness tapes are different.

As in example B1, tapes of the composition layers of the following thicknesses were prepared and tested for properties, and the results are shown in table 9.

TABLE 9

Example 3 (C1 acrylate tape + Electron Beam treatment, C2 acrylate tape + Electron Beam free treatment, tape of C3 acrylate and rubber blend + Electron Beam free treatment)

Example C1A structure as shown in FIG. 5 was prepared by the above solvent method, 1 was a self-adhesive composition layer which was an acrylic type adhesive (adhesive solution composition: 1671 parts by weight of acrylic polymer solution, 386 parts by weight of terpene resin, 328 parts by weight of toluene, 115 parts by weight of toluene as an isocyanate-based crosslinking agent), a single layer thickness of 23 μm,3 was a base material layer, an intermediate base material layer was a PET film 4.5 μm thick, and 2 was a double-sided release film (material was glassine release paper, thickness was 70 μm). The tape thickness was 50 μm. After the structure shown in fig. 5 is obtained, electron irradiation is performed on one side of the upper self-adhesive composition layer and the release paper is on the other side. The electron irradiation instrument was ELECTRON CROSSLINKING AB (Halmstad, sweden), the acceleration voltage was 150keV, and the energy was 100kGy. The density of the resulting tape C1 was 1121kg/m3.

The comparative tape 1 was an acrylic anti-rebound tape C2, the structure of which is shown in FIG. 5,1 was a self-adhesive composition layer (adhesive solution composition: 2057 parts by weight of acrylic polymer, 328 parts by weight of toluene, 115.2 parts by weight of isocyanate-based crosslinking agent toluene solution), a single layer thickness of 23 μm,3 was a base material layer, an intermediate base material layer was a 4.5 μm thick PET film, and 2 was a double-sided release film (material was a glassine release paper, thickness was 70 μm). The comparative tape 1 was not subjected to electron beam treatment. The density of the resulting tape C2 was 1121kg/m ³ 。

The comparative tape 2 was an acrylic anti-rebound tape C3 having a structure shown in FIG. 5, wherein 1 was a self-adhesive composition layer (adhesive solution composition: 401 parts by weight of acrylic polymer, 453 parts by weight of ethyl acetate, 1082 parts by weight of petroleum ether, 354 parts by weight of terpene-phenol resin, 189 parts by weight of styrene-butadiene copolymer (namely D118), 21 parts by weight of epoxy crosslinking agent and aluminum chelate crosslinking agent solution), which was an acrylic and rubber blend type adhesive, had a single layer thickness of 23 μm,3 was a base material layer, an intermediate base material layer was a PET film 4.5 μm thick, and 2 was a double-sided release film (material was a glassine release paper, thickness was 70 μm). The comparative tape 2 was not subjected to electron beam treatment. The density of the resulting tape C3 was 1100kg/m ³ 。

B4 was used as a control.

In each case, an edge tapping test (i.e., method two) is performed. The testing method comprises the following steps: test area 100 x 4.4mm,125 μm PI film was attached to a PC board at 90 ° bend. The test environment was 85 ℃, 85% rh, 3 days. Judging the anti-tilting performance according to whether tilting and tilting height.

Judgment standard: the non-tilting is grade A; the lifting height is less than 2mm and is B-grade, and the complete lifting is C-grade.

Also in each case, the adhesion performance test was carried out by the peel force. The same method was used to prepare samples (150 mm. Times.10 cm,300mm/min peel speed) and peel force test was performed on the steel sheet.

Judgment standard: the peel force test is greater than 9N/cm at A+ level, 8-9N/cm at A level, 5-8N/cm at B level, and less than 5N/cm at C level.

Also in each case, the test for rapid bonding time was passed. The test method was the same as the adhesive property test, and the peel force was evaluated immediately after the tape strips were attached to the steel plate and the PE plate, and after the tape strips were left at room temperature for 14 days.

Judgment standard: if the difference of the stripping force and the stripping force is less than 1N/cm, the grade is A, the difference is between 1N/cm and 2N/cm, the grade is B, and when the difference is more than 3N/cm, the grade is C.

Also in each case, an anti-aging test, an aging resistance, was carried out. The samples were tested after being left at 40 ℃ for 6 months, and the aged performance was evaluated to be the same as the edge tapping grade of the aged product test.

Judgment standard: if the aging edge taping and the adhesive property test are in the same grade with the performance before aging, namely the aging resistance grade is A. If the above condition cannot be satisfied, the grade B is obtained. If the aging edge taping and adhesive performance test is inferior to the performance before aging by one grade, the aging resistance is grade B; if the performance is poor by two grades, the anti-aging performance is C grade.

The results are shown in Table 10 below:

table 10

	AR Performance	High temperature cohesive force	Adhesive properties	Quick bonding	Aging resistance
						C1	B	A(110min)	C(5.0N/cm)	C	A
C2	C	A+(125min)	C(4.5N/cm)	C	C
						C3	C	C(40min)	B(7.5N/cm)	C	C
B4	A	A(112min)	A(9.0N/cm)	A	A

The above results show that B4 also has excellent peel force and aging resistance in addition to maintaining excellent Edge taping test. This is a difficult problem with the current commercially available acrylic anti-rebound tapes.

All documents mentioned in this application are incorporated by reference as if each were individually incorporated by reference. Further, it will be appreciated that various changes and modifications may be made by those skilled in the art after reading the above teachings, and such equivalents are intended to fall within the scope of the claims appended hereto.

Claims

1. A warp-resistant pressure-sensitive adhesive tape, characterized in that the warp-resistant pressure-sensitive adhesive tape comprises at least one adhesive composition layer having a thickness of 3 to 150 μm;

the adhesive composition layer is prepared by coating, drying and electron beam treatment of a self-adhesive composition consisting of the following substances:

a) 40 to 60 parts by weight of a vinylaromatic block copolymer;

b) 40-60 parts by weight of tackifying resin;

c) 0.5-3 parts by weight of an antioxidant; and

d) 100-300 parts by weight of an organic solvent;

the vinyl aromatic block copolymer is a mixture of a styrene-butadiene diblock copolymer and a styrene-butadiene-styrene triblock copolymer, wherein the content of the styrene-butadiene diblock copolymer is 15-80wt%, the content of the styrene block is 30-40wt%, and the proportion of 1, 2-bonded conjugated diene in the butadiene block is 10-15wt%;

the tackifying resin is solid alpha-pinene;

the antioxidant is selected from the group consisting of: irganox168, irganox1010, irganox1076, or a combination thereof;

the organic solvent is selected from the group consisting of: methylcyclohexane, gasoline, toluene, acetone, ethyl acetate, petroleum ether, or combinations thereof;

the adhesive composition layer has a density of 900-1500kg/m ³ ；

The irradiation dose adopted by the electron beam treatment is 80-100kGy;

the self-adhesive composition is free of microspheres;

when the static stripping method is adopted to test the anti-tilting performance of the adhesive tape, the anti-tilting performance of the adhesive tape is grade A, namely the sliding distance is less than 5mm;

when the tape is tested for the anti-tilting performance by adopting the edge-wrapping test method, the anti-tilting performance of the tape is of grade A, namely the tape does not tilt within 3 days;

When the anti-tilting performance of the adhesive tape is tested by adopting a nameplate test method, the anti-tilting performance of the adhesive tape is grade A, namely the tilting height is less than 10 mm.

2. The warp-resistant pressure-sensitive adhesive tape as claimed in claim 1, wherein the adhesive composition layer has a thickness of 3 to 50 μm.

3. The warp-resistant pressure-sensitive adhesive tape of claim 1, wherein the warp-resistant pressure-sensitive adhesive tape comprises a layer of adhesive composition.

4. The anti-warp pressure sensitive adhesive tape of claim 1, wherein the anti-warp pressure sensitive adhesive tape comprises:

1) A first adhesive composition layer;

2) An intermediate substrate layer; and

3) A second adhesive composition layer;

5. The warp-resistant pressure-sensitive adhesive tape as claimed in claim 4, wherein the thickness of the intermediate substrate layer is 0.5 to 100 μm.

6. The lift-resistant pressure-sensitive adhesive tape of claim 1,

the self-adhesive composition consists of:

a) 48 to 53 parts by weight of a vinyl aromatic block copolymer;

b) 48-52 parts by weight of tackifying resin;

c) 0.9-1.5 parts by weight of an antioxidant; and

d) 140-260 parts by weight of an organic solvent.

7. The lift-resistant pressure-sensitive adhesive tape of claim 4, wherein the first adhesive composition layer has a thickness of 3 to 50 μm; and/or

The thickness of the second adhesive composition layer is 3-50 μm.

8. The warp-resistant pressure-sensitive adhesive tape as claimed in claim 1, wherein the adhesive composition layer has a density of 900 to 1100kg/m ³ 。

9. An adhesive assembly, said assembly comprising:

i) A first component;

ii) the anti-lifting pressure sensitive adhesive tape of claim 1;

iii) A second component;

10. The bonding assembly of claim 9, wherein the surface of the first component to be bonded is an irregularly shaped surface; and/or

The surface to be bonded of the second member is an irregularly shaped surface.