CN112708371A

CN112708371A - Shielding adhesive tape and preparation method thereof

Info

Publication number: CN112708371A
Application number: CN202011637661.7A
Authority: CN
Inventors: 袁勇; 杨慧达
Original assignee: Suzhou Deyou New Material Technology Co ltd
Current assignee: Suzhou Deyou New Material Technology Co ltd
Priority date: 2020-12-31
Filing date: 2020-12-31
Publication date: 2021-04-27

Abstract

The invention discloses a shielding adhesive tape and a preparation method thereof. The shielding tape includes: the adhesive comprises a substrate layer and a release material layer, wherein the substrate layer comprises a conductive layer and an insulating thin film layer, and a first adhesive layer is arranged between the conductive layer and the insulating thin film layer; from the type material layer with the substrate layer be provided with the second adhesive layer between the insulating film layer, the second adhesive layer has insulating nature. The shielding adhesive tape combines the conductive shielding adhesive tape and the insulating PET single-sided adhesive tape, the substrate part is made into a whole, the insulating surface is combined with the anti-warping insulating adhesive, the problem of insulativity of the adhesive surface during edge covering is solved, the whole design of the substrate gives enough thickness space for the adhesive, and the adhesive property of the adhesive is fully exerted.

Description

Shielding adhesive tape and preparation method thereof

Technical Field

The invention relates to the field of adhesive tapes, in particular to a shielding adhesive tape and a preparation method thereof.

Background

With the continuous development of the technology level, 3C products such as notebook computers, GPS, IPAD and mobile phones have become an indispensable part of people's daily life, and they bring convenience to our life and also pose hidden dangers to people's health. These electronic products emit high frequency electromagnetic waves when used, and if a human body is exposed to strong electromagnetic waves for a long time, the health of the body is affected, and even cancer lesions are induced. In addition, as the working field environment of modern electronic products is increasingly complex, and many electronic products are complex systems with a mixture of digital and analog systems, the damage of electromagnetic radiation from the outside of the products and electromagnetic interference between internal systems, transmission channels and internal components to various useful information of the products has seriously threatened the stability, reliability and safety of the products, so that the prevention of electromagnetic interference has become one of the more and more focuses of people.

The adhesive tape is one of tools commonly used for fixing and shielding in daily life and work, and can be classified into a high-temperature adhesive tape, a double-sided adhesive tape, a shielding adhesive tape, a special adhesive tape, a pressure-sensitive adhesive tape, a die-cutting adhesive tape and the like according to functions. The shielding adhesive tape has the advantages of electromagnetic shielding, shading, part bonding and fixing, humidity and heat resistance and the like, and can effectively manage electromagnetic waves, light sources, conductivity and the like of electronic equipment. The shielding adhesive tape generally comprises a release layer, a substrate layer and an adhesive layer, is of a multilayer structure, and is reasonably balanced in bonding performance, shielding performance, ESD (electro-static discharge) resistance and the like, so that the problem of manufacturing the shielding adhesive tape is solved.

In some special display panels, an ITO layer on an ITO Glass section at the edge of the panel cannot be completely sealed due to a coating process, and when the edge-covered adhesive tape is a tape with good conductivity, the problem of short circuit can occur.

The scheme that the insulating single-sided adhesive tape is attached to the conductive adhesive surface of the conductive adhesive tape is generally adopted for solving the problems at the present stage, but the thickness is increased due to the fact that multiple layers of adhesive tapes are attached (the shielding adhesive tape and the black PET single-sided adhesive tape), and the thickness of each layer of adhesive tape can only be reduced to meet the requirement of the total thickness due to the limitation of the total thickness, so that the laminated structure is weak in anti-warping performance, and the problem of adhesive tape bonding failure is easy to. If the traditional shielding adhesive tape base material is directly coated with the insulating adhesive, the adhesive has certain fluidity, so that a sharp object pierces the adhesive layer to cause a short circuit problem.

Disclosure of Invention

In order to overcome the defects in the prior art, an embodiment of the present invention provides a shielding tape, including:

the adhesive comprises a base material layer, a first adhesive layer and a second adhesive layer, wherein the base material layer comprises a conductive layer and an insulating film layer;

from type material layer, from type material layer with the substrate layer be provided with second adhesive layer between the insulating film layer, second adhesive layer has insulating nature.

Further, the substrate layer is including setting up the black printing ink layer and the matte oil layer of conducting layer opposite side, the black printing ink layer is located the conducting layer with between the matte oil layer.

Further, the thickness of the base material layer is 12-50 microns, the thickness of the second adhesive layer is 8-50 microns, the thickness of the release material layer is 25-50 microns, and the total thickness of the shielding adhesive tape is 45-150 microns.

Further, the thickness of the matte oil layer in the substrate layer is 2-5 microns, the thickness of the black ink layer is 2-5 microns, the thickness of the conducting layer is 5-20 microns, the thickness of the first adhesive layer is 1-5 microns, and the thickness of the insulating film layer is 2-15 microns.

Further, the second adhesive layer includes a polyacrylate polymer, a tackifying resin, a curing agent, and carbon black.

Further, the polyacrylate polymer comprises methacrylic acid, n-butyl acrylate, hydroxyethyl acrylate, styrene and a silane coupling agent, wherein the silane coupling agent is vinyl triethoxysilane;

the tackifying resin comprises one or more of rosin glyceride, terpene resin, terpene phenolic resin and petroleum resin.

Further, the polyacrylate polymer comprises: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 85-95 parts of ethyl acetate;

10 parts of tackifying resin;

0.9 part of a curing agent;

and 2 parts of carbon black.

Furthermore, the polyacrylate polymer has a molecular weight Mw of 100-120 ten thousand, a molecular weight distribution PDI of 6-10, a glass transition temperature Tg of-40 to-20 ℃, and a rotational viscosity of 10000-20000 cps.

Furthermore, the tackifying resin adopts rosin glyceride with a softening point of 90-110 ℃ and terpene phenol resin with a softening point of 120-150 ℃.

The invention also comprises a preparation method of the shielding adhesive tape, which comprises the following steps:

coating a first adhesive layer between the conductive layer and the insulating film layer;

printing a black ink layer on the other side of the conducting layer, and printing a matte oil layer on the outer side surface of the black ink layer to obtain a substrate layer;

drying, curing and molding the substrate layer;

and coating a second adhesive layer on the release material layer, and laminating the insulation film layer on the substrate layer after drying and drying to form the shielding adhesive tape.

The invention has the following beneficial effects:

the shielding adhesive tape combines the conductive shielding adhesive tape and the insulating PET single-sided adhesive tape, the substrate part is made into a whole, the insulating surface is combined with the anti-warping insulating adhesive, the problem of insulativity of the adhesive surface during edge covering is solved, the whole design of the substrate gives enough thickness space for the adhesive, and the adhesive property of the adhesive is fully exerted. The method for producing the shielding adhesive tape has simple steps.

In order to make the aforementioned and other objects, features and advantages of the invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic view of a shield tape in an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious 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.

In the description of the present invention, it should be noted that the terms "upper", "lower", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature.

The present invention will be described in detail below with reference to the accompanying drawings and examples.

Referring to fig. 1, an embodiment of the present application discloses a shielding tape, which includes a substrate layer 30 and a release material layer 10. The substrate layer 30 includes a conductive layer 33 and an insulating film layer 31, and a first adhesive layer 32 is disposed between the conductive layer 33 and the insulating film layer 31.

From the type material layer 10 with the substrate layer 30 be provided with second adhesive layer 20 between the insulating film layer 31, second adhesive layer 20 has insulating properties.

The shielding adhesive tape combines the conductive shielding adhesive tape and the insulating PET single-sided adhesive tape, the base material part is made into a whole, the insulating surface is combined with the anti-warping insulating adhesive, the problem of insulativity of the adhesive surface during edge covering is solved, the whole design of the base material gives enough thickness space for the adhesive, and the adhesive property of the adhesive is fully exerted.

The substrate layer 30 further comprises a black ink layer 34 and a matte oil layer 35 which are arranged on the other side of the conducting layer 33, and the black ink layer 34 is located between the conducting layer 33 and the matte oil layer 35.

The thickness of the substrate layer 30 is 12-50 microns, the thickness of the second adhesive layer 20 is 8-50 microns, the thickness of the release material layer 10 is 25-50 microns, and the total thickness of the shielding adhesive tape is 45-150 microns. The matte oil layer 35 in the substrate layer 30 is 2-5 microns thick, the black ink layer 34 is 2-5 microns thick, the conducting layer 33 is 5-20 microns thick, the first adhesive layer 32 is 1-5 microns thick, and the insulating film layer 31 is 2-15 microns thick.

Specifically, the release material layer 10 is a PET release film. The conductive layer 33 in the substrate layer 30 is made of metal foil, preferably aluminum foil. The first adhesive layer 32 is made of a pressure sensitive adhesive.

The second adhesive layer 20 includes a polyacrylate polymer, a tackifying resin, a curing agent, and carbon black. Preferably, the polyacrylate polymer comprises methacrylic acid, n-butyl acrylate, hydroxyethyl acrylate, styrene and a silane coupling agent, wherein the silane coupling agent is vinyl triethoxysilane. The tackifying resin comprises one or more of rosin glyceride, terpene resin, terpene phenolic resin and petroleum resin.

The polyacrylate polymer comprises: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyltriethoxysilane, 0.3 part of azobisisobutyronitrile and 85-95 parts of ethyl acetate. 10 parts of tackifying resin. 0.9 part of curing agent. And 2 parts of carbon black.

The polyacrylate polymer has a molecular weight Mw of 100-120 ten thousand, a molecular weight distribution PDI of 6-10, a glass transition temperature Tg of-40 to-20 ℃, and a rotational viscosity of 10000-20000 cps. The solid content of the second adhesive layer prepared by the mass part is 31-51%.

Preferably, the molecular weight Mw is 110 ten thousand and the glass transition temperature Tg is-35 ℃. The rotational viscosity was 17000 cps. The solids content was 50.21%.

Preferably, the tackifying resin adopts rosin glyceride with a softening point of 90-110 ℃ and terpene phenol resin with a softening point of 120-150 ℃.

The second adhesive layer 20 of the masking tape is added with a silane coupling agent, preferably, vinyltriethoxysilane.

The principle of action of the vinyltriethoxysilane is that the vinyltriethoxysilane has two groups per se; the first group can be combined with a macromolecular main chain material of a polyacrylate adhesive; the second group has strong affinity with the adhered object, so that a strong chemical bond is formed on the adhesive interface, and the adhesive strength is greatly improved.

The first group in the vinyl triethoxysilane and the vinyl bond of the acrylate monomer are subjected to free radical polymerization reaction, so that the silane coupling agent directly becomes a part of a macromolecular main chain, and the problem of the migration of the silane coupling agent is avoided.

The second group in the vinyltriethoxysilane endows the acrylate adhesive with the characteristics of a silane coupling agent, so that the adhesive property of the polyacrylate adhesive to the surfaces of plastics, steel plates, glass and the like can be improved, and the adhesive strength, water resistance, weather resistance and the like of the plastics, the steel plates, the glass and the like can be improved.

Compared with the prior art, the embodiment has the following advantages: the defect that the composite adhesive tape is easy to warp reversely due to the fact that the thickness of the shielding adhesive tape is increased due to the fact that the black PET single-sided adhesive tape is compounded with the shielding adhesive tape can be avoided; an insulating film layer is arranged between the conducting layer and the second adhesive layer in the shielding adhesive tape, so that the problem of short circuit caused by the fact that the second adhesive layer is punctured can be avoided.

The shielding adhesive tape in the application has good adhesion with plastics, glass and the like, can also control the overall thickness and ensure the insulating property of the adhesive surface.

The embodiment of the application also comprises a preparation method of the shielding adhesive tape, which comprises the following steps:

drying, curing and molding the substrate layer;

The preparation method of the second adhesive layer comprises the following steps: methacrylic acid, n-butyl acrylate, hydroxyethyl acrylate, styrene and a silane coupling agent are firstly added, azo-bis-isobutyronitrile, a solvent (ethyl acetate) and other free radicals are added for polymerization to form a polyacrylate polymer, and tackifying resin, a curing agent, carbon black, the solvent (ethyl acetate) and the like are added into the polyacrylate polymer for mixing, so that the second adhesive layer is prepared. The amount of solvent added to the polyacrylate polymer can be adjusted to control viscosity and solids content, thereby facilitating coating.

Compared with the prior art, the preparation method in the embodiment has the following advantages: the method for producing and preparing the shielding adhesive tape has simple steps, the conductive shielding adhesive tape and the insulating PET single-sided adhesive tape are combined, the base material part is made into a whole, the insulating surface is combined with the anti-warping insulating adhesive, the problem of the insulativity of the adhesive surface during edge covering is solved, the sufficient thickness space of the adhesive is provided by the whole design of the base material, and the adhesive property of the adhesive is fully exerted.

The components and parts by mass of the second adhesive layer of the masking tape of the comparative example and example, and the other structural layers in the masking tape will be exemplified below. In addition, the polyacrylate polymer in the second adhesive layer in the comparative example did not contain a silane coupling agent, while the polyacrylate polymer in the second adhesive layer in the example contained a silane coupling agent.

Comparative example

The second adhesive layer comprises 100 parts of polyacrylate polymer, 0.9 part of polyisocyanate curing agent, 2 parts of carbon black and 60 parts of ethyl acetate. Specifically, the polyacrylate polymer comprises the following components in parts by weight: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 0.3 part of azobisisobutyronitrile and 92 parts of ethyl acetate. The solid content of the polyacrylate polymer is 50.22%, the molecular weight Mw is 100-120 ten thousand, the glass transition temperature Tg is-40 to-20 ℃, the rotational viscosity is 10000-20000 cps, and the molecular weight distribution PDI is 6-10.

Example one

The second adhesive layer comprises 100 parts of polyacrylate polymer, 0.9 part of polyisocyanate curing agent, 2 parts of carbon black and 60 parts of ethyl acetate. Specifically, the polyacrylate polymer comprises the following components in parts by mass: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 95 parts of ethyl acetate. The solid content of the polyacrylate polymer is 50.21%, the molecular weight Mw is 100-120 ten thousand, the glass transition temperature Tg is-40 to-20 ℃, the rotational viscosity is 10000-20000 cps, and the molecular weight distribution PDI is 6-10.

Example two

The second adhesive layer comprises 100 parts of polyacrylate polymer, 10 parts of tackifying resin, 0.9 part of polyisocyanate curing agent, 2 parts of carbon black and 85 parts of ethyl acetate. Specifically, the polyacrylate polymer comprises the following components in parts by mass: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 95 parts of ethyl acetate. The composition and properties of the polyacrylate polymer in example two were the same as in example one. Wherein the tackifying resin comprises 10 parts of rosin glyceride.

EXAMPLE III

The second adhesive layer comprises 100 parts of polyacrylate polymer, 10 parts of tackifying resin, 0.9 part of polyisocyanate curing agent, 2 parts of carbon black and 85 parts of ethyl acetate. Specifically, the polyacrylate polymer comprises the following components in parts by mass: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 95 parts of ethyl acetate. The composition and properties of the polyacrylate polymer in example three were the same as those in example one. Wherein the tackifying resin comprises 7 parts of rosin glyceride and 3 parts of terpene resin.

Example four

The second adhesive layer comprises 100 parts of polyacrylate polymer, 10 parts of tackifying resin, 0.9 part of polyisocyanate curing agent, 2 parts of carbon black and 85 parts of ethyl acetate. Specifically, the polyacrylate polymer comprises the following components in parts by mass: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 95 parts of ethyl acetate. The composition and properties of the polyacrylate polymer in example four were the same as those in example one. Wherein the tackifying resin comprises 5 parts of rosin glyceride and 5 parts of terpene resin.

EXAMPLE five

The second adhesive layer comprises 100 parts of polyacrylate polymer, 10 parts of tackifying resin, 0.9 part of polyisocyanate curing agent, 2 parts of carbon black and 85 parts of ethyl acetate. Specifically, the polyacrylate polymer comprises the following components in parts by mass: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 95 parts of ethyl acetate. The composition and properties of the polyacrylate polymer in example five were the same as in example one. Wherein the tackifying resin comprises 3 parts of rosin glyceride and 7 parts of terpene resin.

EXAMPLE six

The second adhesive layer comprises 100 parts of polyacrylate polymer, 10 parts of tackifying resin, 0.9 part of polyisocyanate curing agent, 2 parts of carbon black and 85 parts of ethyl acetate. Specifically, the polyacrylate polymer comprises the following components in parts by mass: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 95 parts of ethyl acetate. The composition and properties of the polyacrylate polymer in example six were the same as in example one. Wherein, the tackifying resin comprises 10 parts of terpene resin.

In summary, the compositions of the second adhesive layer in the masking tape of the first to sixth examples and the comparative example are as shown in table 1 below

TABLE 1

The resulting masking tape was prepared for the following tests:

(I) adhesive force

1. Instrumentation and equipment

A tensile testing machine: a constant-speed tensile type tensile testing machine with a tensile speed of 300mm/min was equipped with a recorder measuring 10 kg.

A pressing device: the steel roller coated with rubber on the surface weighs 2kg, is provided with a handle and can reciprocate.

Test panel: PC and GLASS clean test plates (150 mm long, 50mm wide, 1mm thick) were wiped clean with absolute ethanol.

2. Extraction of test piece

A test piece 25mm wide and about 200mm long was cut out.

The non-test side was peeled off the release film and laminated with 0.025mm PET film.

3. Test environmental conditions

The test environment can keep 23 + -2 deg.C and 65 + -5% RH standard state.

4. Test procedure

Attaching the cut test piece to the middle part of the test plate along the longitudinal direction of the test plate, then slowly reciprocating the test piece for three times by using a pressing device for rolling, and placing the test piece for 20 minutes under the state of the standard experimental environment; the test plate is arranged on a tensile testing machine, the lower bending angle of the test piece is 180 degrees, and the test piece is fixed on the chuck on the upper part; peeling was carried out at a speed of 300mm/min, the peeling length was 100mm or more, and the strength was automatically recorded on a recording paper. The same samples were tested in parallel twice.

5. Calculation of results

The average value is read within the range recorded on the recording paper.

(II) holding power

1. Instrumentation and equipment

A dryer: a circulating air dryer capable of maintaining 40 + -2 deg.C was placed with the test surface of the test plate vertical, and a load of 1kg was hung on the lower end of the test piece.

Test panel: test panels (PC, 60mm long, 50mm wide, 1mm thick) were wiped clean with alcohol longitudinally.

2. Cutting of test pieces

A test piece 25mm wide and about 70mm long was cut out.

The non-test side needs to be stripped off the release film layer and compounded with 0.025mm PET film.

3. Test procedure

At the position of the test plate close to the edge, the test piece and the steel plate are effectively attached to the area of 2 with the size of 25 multiplied by 25mm, and then the test piece and the steel plate are repeatedly rolled for three times by a pressing device; the initial joint of the tape and the test board was marked with a thick surface using an oil pen. The test was carried out by placing the plate in a circulating air dryer capable of maintaining a temperature of 80. + -. 2 ℃ and starting to hang a 1000. + -.10 g weight after 20 minutes. After 1h, the distance of displacement is read or the time for dropping the test piece is recorded.

4. Calculation of results

The holding force is the distance of the test piece from the origin after 1 hour, and has a unit of 0.1 mm. When the test piece fell from the test plate, the time of the fall was recorded in min.

(III) constant load

1. Instrumentation and equipment

A dryer: a circulating air dryer capable of maintaining a temperature of 50 + -2 ℃ was placed so that the test surface of the test plate was horizontal, and a load of 50g was applied to the lower end of the test piece.

Test panel: test pieces (SUS304, length 150mm, width 50mm, thickness 1.5mm) were wiped clean with absolute alcohol.

2. Cutting of test pieces

A test piece 20mm wide and 200mm long was cut out.

3. Test procedure

The test piece is adhered with a thickness of 20X 50mm at the position of the test board close to the edge²Area, then rolling and pressing the steel plate once again and again by a pressing device, and standing for 2 hours; the initial joint of the tape and the test board was marked with a thick surface using an oil pen. The test was carried out by placing the plate in a circulating air dryer capable of maintaining a temperature of 50. + -. 2 ℃ and hanging a weight of 50 g. After 1h, read the distance from the origin or record the time at which the test piece was dropped.

4. Calculation of results

The displacement unit is 0.1 mm. When the test piece fell from the test plate, the time of the fall was recorded in min.

(IV) reworkability

For SUS304 mirror surface, SGLC (hot galvanizing aluminum alloy plate) and GLASS, the length of a sample is 150mm, the edge is covered and adhered (the width of each edge is 3 mm), the adhered sample is put into a 50 ℃ oven to be dried for 4h, the whole strip is peeled off at an angle of 180 degrees by hand after being taken out and thermally peeled off and cooled for 1h at normal temperature, and whether the standard is up to the standard is observed: the residual glue area is less than 30%, the ink layer does not fall off, and other abnormalities do not exist.

The test results are reported in table 2 below:

TABLE 2

As can be seen from the above table, the addition of the silane coupling agent and at least one of rosin glyceride and terpene resin in the examples greatly increases the adhesion of the masking tape in the examples, and has stronger affinity for SUS304 and Glass, and higher retention and constant load properties. The requirements are met in all the examples except that the standard of < 30% residual glue area for reworkability is not met in example two.

Specifically, as can be seen from the comparison between the experimental results of the comparative example and the first example, the addition of the silane coupling agent (specifically, vinyltriethoxysilane) to the polyacrylate polymer in the first example makes the adhesive tape in the first example adhere to SUS304 and Glass more strongly, has a small initial adhesion, better holding power and constant load performance, good reworking performance and no adhesive residue.

As can be seen from the comparison between the first example and the test results of the second to sixth examples, the second to sixth examples have the tackifying resin added to the second adhesive layer, so that the adhesive tapes of the second to sixth examples have stronger adhesion to SUS304 and Glass and smaller initial adhesion. The holding force of the fourth to sixth examples is better than that of the second example. The constant load of the other embodiments is equivalent to that of the first embodiment except that the constant load of the second embodiment and the constant load of the third embodiment are not the same as that of the first embodiment. The reworking performance of the adhesive tapes in the second embodiment and the third embodiment is not the same as that of the first embodiment, but the reworking performance of the adhesive tapes in the fourth embodiment and the sixth embodiment is equivalent to that of the first embodiment, and the adhesive tapes in the fourth embodiment and the third embodiment all reach the standard.

The specific components of the tackifying resins in examples two to six are different from each other, resulting in differences between the properties of the adhesive tapes in the respective examples.

From comprehensive evaluation, the performance of the adhesive tape in the first example is superior to that of the comparative example, and the performance of the adhesive tapes in the fourth to sixth examples is superior to that of the first example. The experimental results can therefore show that: the tackifying resin is added into the second adhesive layer, and the silane coupling agent is added into the polyacrylate polymer, so that the adhesive property of the adhesive tape can be improved.

The principle and the implementation mode of the invention are explained by applying specific embodiments in the invention, and the description of the embodiments is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. A masking tape, comprising:

2. The masking tape of claim 1 wherein the substrate layer further comprises a black ink layer and a matte oil layer disposed on the other side of the conductive layer, the black ink layer being disposed between the conductive layer and the matte oil layer.

3. The masking tape of claim 1, wherein the thickness of the base material layer is 12 to 50 μm, the thickness of the second adhesive layer is 8 to 50 μm, the thickness of the release material layer is 25 to 50 μm, and the total thickness of the masking tape is 45 to 150 μm.

4. The shielding tape of claim 2, wherein the thickness of the matte oil layer in the substrate layer is 2 to 5 μm, the thickness of the black ink layer is 2 to 5 μm, the thickness of the conductive layer is 5 to 20 μm, the thickness of the first adhesive layer is 1 to 5 μm, and the thickness of the insulating film layer is 2 to 15 μm.

5. The masking tape of claim 1 wherein the second adhesive layer comprises a polyacrylate polymer, a tackifying resin, a curing agent, and carbon black.

6. The masking tape of claim 5 wherein the polyacrylate polymer comprises methacrylic acid, n-butyl acrylate, hydroxyethyl acrylate, styrene, and a silane coupling agent, wherein the silane coupling agent is vinyl triethoxysilane;

7. The masking tape of claim 6, wherein the polyacrylate polymer comprises: 4 parts of methacrylic acid, 80 parts of n-butyl acrylate, 1.5 parts of hydroxyethyl acrylate, 7 parts of styrene, 3 parts of vinyl triethoxysilane, 0.3 part of azobisisobutyronitrile and 85-95 parts of ethyl acetate;

10 parts of tackifying resin;

0.9 part of a curing agent;

and 2 parts of carbon black.

8. The masking tape according to claim 5, wherein the polyacrylate polymer has a molecular weight Mw of 100 to 120 ten thousand, a molecular weight distribution PDI of 6 to 10, a glass transition temperature Tg of-40 to-20 ℃, and a rotational viscosity of 10000 to 20000 cps.

9. The masking tape of claim 6, wherein the tackifying resin is rosin glyceride with a softening point of 90-110 ℃ and terpene phenol resin with a softening point of 120-150 ℃.

10. The preparation method of the shielding adhesive tape is characterized by comprising the following steps:

drying, curing and molding the substrate layer;