KR102042224B1 - Double sided tape having excellent impact resistance - Google Patents

Abstract

Disclosed is a double-sided tape having excellent impact resistance, and more particularly, a substrate layer, a buffer layer formed on one surface of the substrate layer and formed on an upper surface and a lower surface of the substrate layer on which the buffer layer is formed. It consists of an adhesive layer.
The double-sided tape having the above structure is excellent in adhesive force, and a buffer layer made of acryl foam is formed to exhibit excellent impact resistance.

Description

Double sided tape with excellent impact resistance {DOUBLE SIDED TAPE HAVING EXCELLENT IMPACT RESISTANCE}

The present disclosure relates to a double-sided tape having excellent impact resistance, and more particularly, to a double-sided tape having excellent impact resistance as well as excellent adhesive strength and waterproof performance, and having a buffer layer made of acrylic foam having excellent impact resistance.

Double-sided adhesive tape is mainly used for assembling electronic devices equipped with an image display device or an input device. Specifically, a cover panel for protecting the surface of the electronic device is attached to the touch panel module or the display panel module, or touched. Double-sided adhesive tape is used to bond the panel module and the display panel module.

Conventionally, a double-sided adhesive tape is punched into a shape of a picture frame or the like and used to be disposed around the display screen. In recent years, the opening area has been increased due to the miniaturization of electronic devices and the large screen of the display screen. The joint fixing part around the display screen is narrowing. For this reason, the adhesive area of adhesive tape is decreasing year by year, and as adhesive area becomes narrow, further excellent adhesive performance is calculated | required.

In addition, recently, as the thickness of portable electronic devices such as smartphones and digital cameras is becoming thinner, the thickness of double-sided adhesive tapes is becoming thinner, and in addition to adhesive performance, as consumer demand for waterproof performance of portable electronic devices increases, In order to secure a competitive advantage in the market, the development of double-sided tape with waterproof performance is being made.

However, in the case of the conventionally developed double-sided adhesive tape, the waterproof performance of the adhesive layer formed on the double-sided adhesive tape is usually maintained, but when an impact is applied from the outside, there is a problem in that the adhesive layer is cracked and the waterproof performance is lost. .

Korea Patent Registration No. 10-1527184 (2015.06.02) Korean Patent Publication No. 10-2015-0126588 (2015.11.12)

Disclosed is to provide a double-sided tape having excellent impact resistance, as well as excellent adhesion and waterproof performance, and a buffer layer made of acrylic foam is formed to exhibit excellent impact resistance.

As an example, the contents of the present disclosure may include a base layer, a buffer layer formed on one surface of the base layer, and an adhesive layer formed on upper and lower surfaces of the base layer on which the buffer layer is formed. The double-sided tape excellent in impact resistance is described.

Preferably, the base layer is made of one selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, and polyimide, and may be formed to a thickness of 12 to 100 micrometers.

More preferably, the buffer layer may be formed to a thickness of 50 to 300 micrometers.

More preferably, the acrylic foam may be prepared by mixing and foaming 100 to 350 parts by weight of water, 100 to 350 parts by weight of water, 3 to 4 parts by weight of foaming agent, 1 to 3 parts by weight of filler and 2 to 4 parts by weight of curing agent. .

Even more preferably, the acrylic emulsion may be composed of a solid content of at least 30% by weight.

Even more preferably, the pressure-sensitive adhesive layer is made of an acrylic pressure-sensitive adhesive, it may be formed to a thickness of 50 to 100 micrometers.

As described above, the double-sided tape having excellent impact resistance not only has excellent adhesion and waterproof performance, but also provides a double-sided tape showing excellent impact resistance by forming a buffer layer made of acrylic foam.

1 is an exploded perspective view showing a double-sided tape having excellent impact resistance disclosed.

In the following, preferred embodiments of the present invention and the physical properties of each component will be described in detail, which is intended to explain in detail enough to be able to easily carry out the invention by one of ordinary skill in the art, This does not mean that the technical spirit and scope of the present invention is limited.

The double-coated tape having excellent impact resistance is formed on the base layer 10, one surface of the base layer 10, and a buffer layer 20 made of acrylic foam and an upper surface of the base layer 10 on which the buffer layer 20 is formed. And an adhesive layer 30 formed on the lower surface.

The base layer 10 is a layer of a double-sided tape having excellent impact resistance and is made of a thickness of 12 to 100 micrometers. The double-sided tape having excellent impact resistance exhibits a certain shape and is not easily deformed by external force. It also plays a role of preventing water and giving waterproof performance to double-sided tape.

When the thickness of the base layer 10 is less than 12 micrometers, the double-sided tape may be easily deformed or cracked due to impact or tensile force on the outside, and if the thickness of the base layer 10 exceeds 100 micrometers The thickness of the double-sided tape is excessively increased, making it unsuitable for electronic devices that are miniaturized and thinned.

In addition, the base layer 10 is preferably made of a resin having a relatively low price and excellent mechanical properties such as polyethylene terephthalate, polyethylene naphthalate and polyimide.

The buffer layer 20 is formed of a thickness of 50 to 300 micrometers on one surface of the substrate layer 10 and made of acrylic foam, and serves to improve impact resistance on the double-sided tape having excellent impact resistance.

The acrylic foam is prepared by mixing and foaming 100 to 350 parts by weight of water, 100 to 350 parts by weight of water, 3 to 4 parts by weight of foaming agent, 1 to 3 parts by weight of filler, and 2 to 4 parts by weight of curing agent, and more specifically, acrylic emulsion. 100 parts by weight, 100 to 350 parts by weight of water, 3 to 4 parts by weight of foaming agent, 1 to 3 parts by weight of filler and 2 to 4 parts by weight of curing agent were added to a mechanical stirrer and stirred at a speed of 1500 to 2500 rpm at a temperature of 35 to 45 ° C. However, the stirrer is preferably to use a bubble generating stirrer to generate bubbles.

When the agitator is stirred using the bubble-generating stirrer, bubbles are formed in the acrylic resin to physically expand the foam, and when the foamed foam is formed on one surface of the base layer 10 through a comma coating method, a curing agent is formed. Curing due to the progress is provided to the buffer layer (20).

At this time, the acrylic emulsion is preferably used that the content of the solid content of 30% by weight or more, if the content of the acrylic emulsion solid content of 30% by weight or more, the buffer layer 20 in the process of configuring the buffer layer 20 made of acrylic foam It is easy to adjust the thickness of the drying time is reduced because the productivity of the double-sided tape can be improved.

The blowing agent contains 3 to 4 parts by weight and serves to foam the acrylic emulsion. When the content of the blowing agent is less than 3 parts by weight, the foamability of the acrylic emulsion is lowered, and when the content of the blowing agent exceeds 4 parts by weight. The foaming degree of the acrylic emulsion may be excessively improved, and thus the mechanical properties of the buffer layer may be reduced.

In this case, the foaming agent is not particularly limited as long as the foaming agent can foam the acrylic emulsion, and any foaming agent may be used, but is preferably made of hydrocarbon.

In addition, the filler contains 1 to 3 parts by weight and serves to improve the mechanical properties of the acrylic foam constituting the buffer 20, the above effect is insignificant if the content of the filler is less than 1 part by weight, When the content of the filler exceeds 3 parts by weight, the effect is not greatly improved, increasing the manufacturing cost and lowering the elasticity of the acrylic foam.

At this time, the filler is made of talc, calcium carbonate, silicon nitride, silicon oxide, aluminum oxide, aluminum hydroxide, magnesium oxide, magnesium hydroxide, calcium oxide, calcium hydroxide, carbon black, carbon fiber, antimony oxide, antimony pentoxide, zirconia and zinc oxide It is preferably made of one or more selected from the group.

In addition, the curing agent contains 2 to 4 parts by weight, and improves the efficiency of the acrylic foam manufacturing process by improving the rate of curing after the foam is foamed, serves to provide an excellent acrylic foam stability.

At this time, it is preferable that the said hardening agent consists of isocyanate.

When the thickness of the buffer layer 20 is less than 50 micrometers, the impact resistance of the double-sided tape having improved impact resistance is lowered. When the thickness of the buffer layer 20 exceeds 300 micrometers, the thickness of the double-sided tape is excessively increased. It is not suitable for electronic devices that are miniaturized and thinned.

The pressure-sensitive adhesive layer 30 is formed with a thickness of 50 to 100 micrometers on the upper and lower surfaces of the base layer 10 on which the buffer layer 20 is formed and is made of an acrylic pressure-sensitive adhesive having a weight average molecular weight of 800000 to 900000. Since the acrylic pressure-sensitive adhesive having the weight average molecular weight exhibits excellent adhesive performance, it provides a double-sided tape having excellent adhesive performance.

If the thickness of the adhesive layer 30 is less than 50 micrometers, the adhesive performance and impact resistance is lowered. If the thickness of the adhesive layer 30 exceeds 100 micrometers, the adhesive performance of the double-sided tape is not greatly improved. The thickness is excessively increased, making it unsuitable for electronic devices that are miniaturized and thinned.

Hereinafter, the physical properties of the double-sided tape manufactured by the method of manufacturing the double-sided tape excellent impact resistance and the manufacturing method disclosed will be described with reference to the embodiment.

<Example 1>

A substrate layer was prepared from a 50 micron-thick polyethylene terephthalate film, 100 parts by weight of an acrylic emulsion, 100 parts by weight of water, 3.5 parts by weight of a blowing agent (hydrocarbon), and 2 parts of a filler (silicon oxide) on the upper surface of the substrate layer. 3 parts by weight of the curing agent (isocyanate) and then mixed into a mechanical stirrer and foamed for 40 minutes at a speed of 2000 rpm at a temperature of 40 ℃ to apply a foam prepared by a comma coating method to a thickness of 50 micrometers to form a buffer layer In addition, an adhesive layer was formed by applying an acrylic adhesive having a weight average molecular weight of 850000 to a thickness of 75 micrometers on the upper and lower surfaces of the substrate layer on which the buffer layer was formed, thereby preparing a double-sided tape having excellent impact resistance.

<Example 2>

Proceed in the same manner as in Example 1, the thickness of the buffer layer was formed to 100 micrometers to prepare a double-sided tape excellent in impact resistance.

<Example 3>

Proceed in the same manner as in Example 1, the thickness of the buffer layer was formed to 200 micrometers to prepare a double-sided tape excellent in impact resistance.

<Example 4>

Proceed in the same manner as in Example 1, the thickness of the buffer layer was formed to 300 micrometers to prepare a double-sided tape excellent in impact resistance.

Comparative Example 1

A substrate layer is made of a polyethylene terephthalate film having a thickness of 50 micrometers, and a buffer layer composed of 100 parts by weight of polyurethane and 16 parts by weight of a filler (polymethylmethacrylate having a particle size of 30 micrometers) on the upper surface of the substrate layer. Was formed to a thickness of 50 micrometers, and the adhesive layer was formed by applying an acrylic adhesive having a weight average molecular weight of 850000 to a thickness of 75 micrometers on the upper and lower surfaces of the base layer on which the buffer layer was formed to form an adhesive layer. A double sided tape was prepared.

The shock absorption rate of the double-sided tape having excellent impact resistance prepared through Examples 1 to 4 and Comparative Example 1 is shown in Table 1 below.

{However, the shock absorption rate is the steel plate and the SUS plate in sequence on the impact amount measuring sensor, and after the double-sided tape prepared in Examples 1 to 4 and Comparative Example 1 to the size of 10cm × 10cm in length and then the specimen It was attached to the upper surface of the SUS plate, and after dropping the 16g steel ball to the upper surface of the specimen at a height of 100cm was used to check the value of the impact amount measuring sensor.

At this time, the impact absorption rate was calculated by the impact amount on the SUS plate without the specimen and the impact amount on the SUS plate attached to the specimen, respectively, the calculation method is as follows.

Impact Absorption Rate (%) = (Suspension of SUS Plate without Specimen-SUS Plate Impact with Specimen) / SUS Plate Impact with No Specimen × 100}

TABLE 1

As shown in Table 1 above, it can be seen that the double-sided tape prepared through the disclosed Examples 1 to 4 has a superior shock absorption rate compared to the double-sided tape prepared through Comparative Example 1.

In particular, even when comparing Example 1 and Comparative Example 1 in which the same thickness buffer layer was formed, it can be seen that the shock absorption of Example 1 using acrylic foam as the buffer layer was superior to Comparative Example 1 using polyurethane as the buffer layer. .

Therefore, the double-sided tape having excellent impact resistance as described above not only has excellent adhesion and waterproof performance, but also has a buffer layer made of acrylic foam, thereby exhibiting excellent impact resistance.

10; Substrate layer
20; Buffer layer
30; Adhesive layer

Claims (6)

A substrate layer formed of one selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate and polyimide, and having a thickness of 12 to 100 micrometers;
A buffer layer formed on one surface of the base layer and made of acryl foam and having a thickness of 50 to 300 micrometers; And
And a pressure-sensitive adhesive layer formed on the upper and lower surfaces of the base layer on which the buffer layer is formed.
The acrylic foam is prepared by mixing and foaming 100 to 350 parts by weight of water, 3 to 4 parts by weight of foaming agent, 1 to 3 parts by weight of filler and 2 to 4 parts by weight of curing agent to 100 parts by weight of an acrylic emulsion having a solid content of 50% by weight or more. ,
The pressure-sensitive adhesive layer is made of an acrylic pressure-sensitive adhesive, a double-sided tape having excellent impact resistance, characterized in that formed in a thickness of 50 to 100 micrometers.





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