CN114828603A

CN114828603A - Electromagnetic shielding film

Info

Publication number: CN114828603A
Application number: CN202210185841.9A
Authority: CN
Inventors: 夏厚君; 杨晓明
Original assignee: Zhejiang Ouren New Materials Co ltd
Current assignee: Zhejiang Ouren New Materials Co ltd
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2022-07-29
Also published as: CN114716929A; CN112143394B; CN112143394A; CN115260932A; WO2020258699A1; CN115260932B

Abstract

The invention discloses an electromagnetic shielding film which comprises a black ink layer, a base material layer and an adhesive layer, wherein the black ink layer and the adhesive layer are respectively positioned on the upper surface and the lower surface of the base material layer; the black ink layer is obtained by drying black ink, and the black ink comprises the following components in parts by weight: the light absorption material comprises water-based polyurethane, carbon black, 1' -methylene tri (4-isocyanic acid) benzene, sodium silicate, carboxymethyl cellulose, sodium tripolyphosphate, polyethyleneimine, octadecyl dimethyl benzyl ammonium chloride, a light absorption agent, a coupling agent, chitosan and deionized water. The electromagnetic shielding film has fingerprint resistance, fingerprint traces can not be left after the electromagnetic shielding film is used for many times in various environments, the corrosion of fingerprint sweat stains to the adhesive tape can be avoided, and the cleaning difficulty is greatly reduced.

Description

Electromagnetic shielding film

Technical Field

The invention belongs to the technical field of adhesive tapes, and particularly relates to an electromagnetic shielding film.

Background

The electromagnetic shielding film is a transparent shielding material capable of blocking electromagnetic wave penetration, preventing electromagnetic radiation, protecting electronic components and resisting electromagnetic interference, and the requirements on the electromagnetic shielding film are continuously improved along with the continuous development of electronic products in recent years. The wireless charging technology mainly comprises three main categories of magnetic induction wireless charging, magnetic resonance wireless charging and radio frequency wireless charging, and along with popularization of the wireless charging technology, a plurality of products applying the magnetic induction wireless charging technology emerge in the market. In order to obtain higher charging efficiency and reduce or eliminate the influence of an electromagnetic field on the mobile phone during charging, an electromagnetic shielding film is required for shielding. The electromagnetic shielding film is used for isolating the influence of an electromagnetic field on the mobile phone, preventing materials such as metal and the like from absorbing the electromagnetic wave emitted by the transmitting terminal equipment and generating a magnetic field in the opposite direction. In the wireless charging receiving end of the mobile phone, if the electromagnetic shielding film is not arranged, the wireless charging equipment cannot complete short-distance charging work. The electromagnetic shielding film needs to be fixed on the interference source through an adhesive tape. At present, the film does not have anti-fingerprint performance, and the residual fingerprint traces after multiple uses not only affect the appearance, but also have certain influence on the performance of the film material.

Disclosure of Invention

The invention aims to provide an electromagnetic shielding film which has fingerprint resistance, does not leave fingerprint traces after being used for many times in various environments, and can avoid the corrosion of fingerprint sweat stains on the adhesive tape.

In order to achieve the purpose, the invention adopts the technical scheme that: an electromagnetic shielding film comprises a black ink layer, a base material layer and an adhesive layer, wherein the black ink layer and the adhesive layer are respectively positioned on the upper surface and the lower surface of the base material layer, and a release layer is arranged on one side, opposite to the base material layer, of the adhesive layer;

the black ink layer is obtained by drying black ink, and the black ink comprises the following components in parts by weight: 60 parts of waterborne polyurethane, 1 part of carbon black, 1.5 parts of 1, 1' -methylene tri (4-isocyanic acid) benzene, 1.5 parts of sodium silicate, 1.2 parts of carboxymethyl cellulose, 0.1 part of sodium tripolyphosphate, 1 part of polyethyleneimine, 2 parts of octadecyl dimethyl benzyl ammonium chloride, 2 parts of a light absorbent, 1 part of a coupling agent, 0.8 part of chitosan and 18 parts of deionized water.

The technical scheme of further improvement in the technical scheme is as follows:

1. in the above scheme, the light absorbent is selected from nano Al/Al ₂ O ₃ A core-shell material.

2. In the scheme, the coupling agent is selected from a coupling agent KH-580.

3. In the scheme, the base material layer is a 2-4 mu m PET polyester film.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

according to the electromagnetic shielding film, the polyethyleneimine and the octadecyl dimethyl benzyl ammonium chloride are added into the waterborne polyurethane, the carbon black and the 1, 1' -methylene tris (4-isocyanic acid) benzene, so that the fingerprint-proof adhesive tape has fingerprint-proof performance, fingerprint traces cannot be remained after repeated use in various environments, and the corrosion of fingerprint sweat stains to the adhesive tape can be avoided; meanwhile, the anti-stain performance of the anti-fingerprint adhesive tape is enhanced, namely stain on the adhesive tape can be easily wiped off without residue after being left for a period of time in a high-temperature and high-humidity environment, so that the attachment of stains is reduced, and the cleaning difficulty is greatly reduced.

Drawings

Fig. 1 is a schematic structural view of an electromagnetic shielding film according to the present invention.

In the above drawings: 1. a black ink layer; 2. a substrate layer; 3. an adhesive layer; 4. and a release layer.

Detailed Description

In the description of this patent, it is noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention; the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; furthermore, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "coupled" are to be construed broadly and encompass, for example, both fixed and removable coupling as well as integral coupling; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The meaning of the above terms in this patent may be specifically understood by those of ordinary skill in the art.

The invention is further described below with reference to the following examples:

example (b): an electromagnetic shielding film comprises a black ink layer 1, a base material layer 2 and an adhesive layer 3, wherein the black ink layer 1 and the adhesive layer 3 are respectively positioned on the upper surface and the lower surface of the base material layer 2, and a release layer 4 is arranged on one side, opposite to the base material layer 2, of the adhesive layer 3;

the black ink layer 1 is obtained by drying black ink, and the black ink comprises the following components in parts by weight: 60 parts of waterborne polyurethane, 1 part of carbon black, 1.5 parts of 1, 1' -methylene tri (4-isocyanic acid) benzene, 1.5 parts of sodium silicate, 1.2 parts of carboxymethyl cellulose, 0.1 part of sodium tripolyphosphate, 1 part of polyethyleneimine, 2 parts of octadecyl dimethyl benzyl ammonium chloride, 2 parts of a light absorbent, 1 part of a coupling agent, 0.8 part of chitosan and 18 parts of deionized water.

The light absorbing agent is selected from nano Al/Al ₂ O ₃ The core-shell material, the coupling agent is selected from a coupling agent KH-580.

The preparation method of the electromagnetic shielding film comprises the following steps: adding 60-80 parts of waterborne polyurethane, 15-25 parts of deionized water, 1-5 parts of 1, 1' -methylene tri (4-isocyanic acid) benzene, 0.01-0.03 part of sodium tripolyphosphate, 1-5 parts of carbon black, 1-1.5 parts of sodium silicate, 1-5 parts of polyethyleneimine, 0.5-2 parts of octadecyl dimethyl benzyl ammonium chloride, 0.5-1.5 parts of coupling agent, 1-1.5 parts of carboxymethyl cellulose, 2-4 parts of light absorbent and 0.5-1 part of chitosan into a high-speed stirring dispersing agent for stirring, and uniformly mixing to obtain black ink;

and coating the black ink on the substrate layer 2, and drying to obtain the electromagnetic shielding film.

Comparative examples 1 to 2: an electromagnetic shielding film comprises a black ink layer 1, a base material layer 2 and an adhesive layer 3, wherein the black ink layer 1 and the adhesive layer 3 are respectively positioned on the upper surface and the lower surface of the base material layer 2, and a release layer 4 is arranged on one side, opposite to the base material layer 2, of the adhesive layer 3;

the black ink layer 1 is obtained by drying black ink, and the black ink comprises the following components in parts by weight, as shown in table 2:

TABLE 1

Components	Comparative example 1	Comparative example 2
			Aqueous polyurethane	60 portions of	80 portions
Carbon black	1 part of	5 portions of
			1, 1' -methine tris (4-isocyanato) benzene	1.8 parts of	2 portions of
Sodium silicate	1.5 parts of	1.2 parts of
			Carboxymethyl cellulose	1.2 parts of	1.5 parts of
Sodium tripolyphosphate	0.1 part	0.2 part
			Polyethylene imine	-	5 portions of
Octadecyl dimethyl benzyl ammonium chloride	2 portions of	-
			Light absorber	2.5 parts of	3 portions of
Coupling agent	0.8 portion of	0.5 portion
			Chitosan	0.8 portion of	0.6 part
Deionized water	18 portions of	20 portions of

Comparative example the procedure is as in example.

Comparative example 1 light absorber selected from nano Al/Al ₂ O ₃ The core-shell material is characterized in that the coupling agent is selected from a coupling agent KH-580, the base material layer 2 is a PET layer with the thickness of 2 mu m, and the thickness of the black ink layer 1 is 1 mu m.

In comparative example 2, the light absorbing agent was selected from nano nickel powder, the coupling agent was selected from coupling agent KBM403, the base material layer 2 was a PET layer having a thickness of 2.5 μm, and the thickness of the black ink layer 1 was 1.3 μm.

The properties of the electromagnetic shielding films prepared in the above examples and comparative examples 1 to 2 are shown in table 2:

TABLE 2

The test method is as follows:

fingerprint prevention test: the appearance of the black ink layer was observed by pressing 10 times with a finger on the black ink layer, and the meanings indicated by the relevant symbols in table 2 were as follows:

o: without fingerprint

X: a fingerprint exists;

and (3) dirt resistance test: and (3) using a ZEBRA oil pen, wherein the angle between the oil pen and the surface of the film layer is about 90 degrees, applying a force of about 1N to draw 5 10mm handwriting on the surface of the film layer at a constant speed, then placing the sample in an environment with the temperature of 60 ℃ and the humidity of 95 percent for 2 hours, taking out the sample, and wiping the surface with alcohol, wherein no trace residue is left on the surface of the sample, and the sample is qualified.

As shown in the evaluation results of table 2, the electromagnetic shielding films of examples have excellent fingerprint resistance, no trace remains in the case of multiple finger presses, and the stains on the adhesive tape can be easily wiped off and do not remain in a high-temperature and high-humidity environment for a while, while comparative example 1 has relatively poor fingerprint resistance and comparative example 2 has much poor stain resistance; therefore, the anti-fingerprint performance is improved, the anti-dirt performance of the electromagnetic shielding film is enhanced, namely, dirt on the adhesive tape can be easily wiped off without being left in a high-temperature and high-humidity environment for a period of time, so that the adhesion of dirt is reduced, and the cleaning difficulty is greatly reduced.

The above embodiments are only for illustrating the technical idea and features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the content of the present invention and implement the present invention, and not to limit the protection scope of the present invention by this means. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. An electromagnetic shielding film, comprising: the adhesive comprises a black ink layer (1), a base material layer (2) and an adhesive layer (3), wherein the black ink layer (1) and the adhesive layer (3) are respectively positioned on the upper surface and the lower surface of the base material layer (2), and a release layer (4) is arranged on one side, opposite to the base material layer (2), of the adhesive layer (3);

the black ink layer (1) is obtained by drying black ink, and the black ink comprises the following components in parts by weight: 60 parts of waterborne polyurethane, 1 part of carbon black, 1' -methylene tri (4-isocyanic acid) benzene 1.5 parts, 1.5 parts of sodium silicate, 1.2 parts of carboxymethyl cellulose, 0.1 part of sodium tripolyphosphate, 1 part of polyethyleneimine, 2 parts of octadecyl dimethyl benzyl ammonium chloride, 2 parts of light absorbent, 1 part of coupling agent, 0.8 part of chitosan and 18 parts of deionized water.

2. The electromagnetic shielding film according to claim 1, wherein: the light absorbing agent is selected from nano Al/Al ₂ O ₃ A core-shell material.

3. The electromagnetic shielding film according to claim 1, wherein: the coupling agent is selected from a coupling agent KH-580.

4. The electromagnetic shielding film according to any one of claims 1 to 3, wherein: the base material layer (1) is a 2-4 mu m PET polyester film.