KR102244481B1 - Water blocking tape having excellent restoring force to deformation - Google Patents

Abstract

The present invention relates to a waterproof tape having excellent restoring force to deformation. The waterproof tape may include a base layer, and foamed adhesive layers formed on the upper and lower surfaces of the base layer. The foamed adhesive layers may include an acrylic resin polymer and an acid additive having a hydroxyl group (-OH) or a carboxyl group (-COOH) at both ends, respectively, and may respectively have a thickness of 35 to 135 micrometers.

Description

Waterproof tape with excellent deformation resilience {WATER BLOCKING TAPE HAVING EXCELLENT RESTORING FORCE TO DEFORMATION}

The disclosed contents relate to a waterproof tape having excellent deformation resilience, and more particularly, to a waterproof tape having excellent deformation resilience by including a modified foam adhesive layer as well as having impact resistance and waterproof function.

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

Conventionally, double-sided adhesive tape is used by being punched into a shape such as a picture frame and disposed around a display screen. Recently, the opening area has been increased due to the miniaturization of electronic devices and the enlargement of the display screen. The joint and fixed portions around the display screen are becoming narrower. For this reason, the adhesive area of the adhesive tape is decreasing year by year, and further excellent adhesive performance is required as the adhesive area becomes narrower.

In addition, in recent years, as the thickness of portable electronic devices such as smartphones and digital cameras gradually decreases, the thickness of double-sided adhesive tapes is becoming thinner. In order to secure a competitive advantage in the market, the development of double-sided tapes 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. .

Korean Patent Registration No. 10-1527184 Korean Patent Publication No. 10-2015-0126588

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The disclosed content is to provide a waterproof tape having not only impact resistance and waterproof function, but also excellent deformation and resilience.

As an embodiment, the content of this disclosure includes a base layer, and a foamed adhesive layer formed on an upper surface and a lower surface of the base layer, wherein each of the foamed adhesive layers is an acrylic resin polymer, and a hydroxyl group ( -OH) or an acid additive having a carboxyl group (-COOH), and the foamed adhesive layer is described for a waterproof tape having a thickness of 35 to 135 micrometers and excellent in deformation resilience.

Preferably, the base layer may include polyethylene terephthalate (PET), and may be formed to a thickness of 9 to 75 micrometers.

More preferably, the base layer may be formed to a thickness of 15 to 40 micrometers, the foamed adhesive layer may be formed to a thickness of 40 to 110 micrometers, respectively, and the waterproof tape having excellent deformation restoring power is a total It may be formed to a thickness of 100 to 300 micrometers.

More preferably, the foamed adhesive layer may be made of 100 parts by weight of an acrylic resin polymer, 0.1 to 3.0 parts by weight of a foaming agent, 0.5 to 1.5 parts by weight of a curing agent, 0.5 to 1.5 parts by weight of an acid additive, and 100 parts by weight of a solvent.

Even more preferably, the acid additive may include at least one selected from the group consisting of adipic acid, succinic acid, polytetramethylene glycol, polyester polyol, and polycarbonate polyol.

Even more preferably, the curing agent may include a toluene diisocyanate curing agent and/or an isophorone diisocyanate curing agent.

Even more preferably, the acrylic resin polymer is 50 parts by weight of N-butyl acrylate, 40 parts by weight of 2-ethylhexyl acrylate, 5 parts by weight of methyl acrylate, 3 parts by weight of cyclohexyl methacrylate, and 2 parts by weight of acrylic acid. It may be made, and the weight average molecular weight may be 400,000 to 900,000.

Even more preferably, the solvent may include at least one of methyl ethyl ketone, toluene, ethyl acetate, isopropyl alcohol, and xylene.

The waterproof tape as described above may not only have impact resistance and waterproof function, but also have excellent deformation and resilience.

1 is a cross-sectional view for explaining a waterproof tape having excellent deformation restoring force disclosed.
2 and 3 are schematic diagrams showing a method of measuring the deformation restoring force of a waterproof tape manufactured through the disclosed Examples and Comparative Examples.

Hereinafter, a preferred embodiment of the present invention and the physical properties of each component will be described in detail, but this is for explaining in detail enough that one of ordinary skill in the art can easily carry out the invention, This does not mean that the technical spirit and scope of the present invention are limited.

Waterproof tape with excellent deformation resilience

Referring to FIG. 1, the waterproof tape having excellent deformation restoring power may include a base layer 10 and a foam adhesive layer 30 formed on an upper surface and a lower surface thereof, respectively.

The base layer 10 may include polyethylene terephthalate (PET) as a base layer of the disclosed waterproof tape having excellent deformation restoring power, and may be formed to a thickness of 15 to 40 micrometers.

If the thickness of the base layer 10 is less than 15 micrometers, the waterproof tape may be easily deformed or cracked due to external impact or tensile force, and may not be restored from the deformation or crack. When the thickness of the base layer 10 exceeds 40 micrometers, the thickness of the waterproof tape is excessively increased, and thus it may not be suitable for electronic devices that are miniaturized and thinned.

The foamed adhesive layer 30 may be formed on the upper and lower surfaces of the base layer 10, respectively, and may be formed of a foamed acrylic adhesive.

In exemplary embodiments, the foamed adhesive layer 30 may be formed by drying and foaming the modified adhesive layer 20 at a high temperature (170° C.).

At this time, the modified adhesive layer 20 may be formed to a thickness of 50 to 75 micrometers. More preferably, the modified adhesive layer 20 may be formed to a thickness of 70 micrometers.

The modified adhesive layer 20 includes 100 parts by weight of an acrylic resin polymer, 0.5 to 3.0 parts by weight of a foaming agent, 0.5 to 1.5 parts by weight of an acid additive having a hydroxy group (-OH) or a carboxyl group (-COOH) at both ends, and 0.5 to 0.5 parts by weight of an additive. It may consist of 1.5 parts by weight and 100 parts by weight of the solvent.

The acrylic resin polymer may be composed of 50 parts by weight of N-butyl acrylate, 40 parts by weight of 2-ethylhexyl acrylate, 5 parts by weight of methyl acrylate, 3 parts by weight of cyclohexyl methacrylate, and 2 parts by weight of acrylic acid, a weight average The molecular weight may be 400,000 to 900,000. More preferably, the weight average molecular weight of the acrylic resin polymer may be 600,000.

The curing agent may include at least one selected from the group consisting of a toluene diisocyanate curing agent, an epoxy curing agent, an isophorone diisocyanate curing agent, a xylene diisocyanate curing agent, and an aziridine curing agent.

The acid additive is an acid additive having a hydroxy group (-OH) or carboxyl group (-COOH) at both ends, and from the group consisting of adipic acid, succinic acid, polytetramethylene glycol, polyester polyol and polycarbonate polyol It may include at least one selected.

When the acid additive is added in an amount of 0.5 to 1.5 parts by weight based on 100 parts by weight of the acrylic resin polymer, it is possible to increase the deformation recovery force through a loose crosslinking structure. If it is less than 0.5 parts by weight, the effect may be insignificant, and if it exceeds 1.5 parts by weight, the shock absorption rate may be lowered.

The solvent may include at least one of methyl ethyl ketone, toluene, ethyl acetate, isopropyl alcohol, and xylene.

In example embodiments, the foamed adhesive layer 30 may be formed by drying the modified adhesive layer 20 at 170° C. and foaming.

On the other hand, the foamed adhesive layer 30 formed by foaming the modified adhesive layer 20 may be formed to a thickness greater than the thickness of the modified adhesive layer 20, for example, a thickness of 60 to 90 micrometers. More preferably, the foamed adhesive layer 30 may be formed to a thickness of 85 micrometers.

At this time, if the thickness of the foamed adhesive layer 30 is less than 60 micrometers, the adhesive performance and impact resistance may be deteriorated, and if the thickness exceeds 90 micrometers, the adhesive performance is not significantly improved and the thickness of the waterproof tape is reduced. Due to excessive increase, it may not be suitable for electronic devices that are miniaturized and thinned.

In one embodiment, the foamed adhesive layer 30 may further include air bubbles compared to the modified adhesive layer 20.

In one embodiment, the waterproof tape having excellent deformation restoring power comprises a base layer 10 having a thickness of 25 to 30 micrometers, and foam adhesive layers 30 having a thickness of 85 to 87 micrometers each formed on the upper and lower surfaces thereof. It may include, and may have a total thickness of 195 to 205 micrometers.

Manufacturing method of waterproof tape with excellent deformation resilience

Hereinafter, a method of manufacturing a waterproof tape having excellent deformation resilience will be described by way of example.

<Example 1>

After forming the base layer 10 containing polyethylene terephthalate (PET) to a thickness of 25 micrometers, 50 parts by weight of N-butyl acrylate, 40 parts by weight of 2-ethylhexyl acrylate, methylacrylic on the upper surface thereof 5 parts by weight of a rate, 3 parts by weight of cyclohexyl methacrylate and 0.5 parts by weight of adipic acid are polymerized, and 100 parts by weight of an acrylic resin polymer having a weight average molecular weight of 600,000, 1 part by weight of a blowing agent (SDI, MSH-320), Modified adhesive layer by coating a mixture consisting of 1 part by weight of a curing agent (0.5 parts by weight of toluene diisocyanate and 0.5 parts by weight of isophorone diisocyanate) and 100 parts by weight of a solvent (methyl ethyl ketone) to a thickness of 75 micrometers by comma coating method (20) was formed. Thereafter, the modified adhesive layer 20 was secondarily dried and foamed at 170° C. to form a foamed adhesive layer 30 of 85 micrometers.

Next, substantially the same material as the mixture contained in the modified adhesive layer 20 on the lower surface of the base layer 10, that is, 100 parts by weight of the acrylic resin polymer, 1 part by weight of a foaming agent (SDI MSH-320), Modified adhesive layer by coating a mixture consisting of 1 part by weight of a curing agent (0.5 parts by weight of toluene diisocyanate and 0.5 parts by weight of isophorone diisocyanate) and 100 parts by weight of a solvent (methyl ethyl ketone) to a thickness of 75 micrometers by comma coating method (20) was formed, and the modified adhesive layer 20 was secondarily dried and foamed at 170° C. to form a foamed adhesive layer 30 of 85 micrometers.

<Example 2>

A waterproof tape having excellent deformation resilience was prepared in the same manner as in Example 1, except that 0.5 parts by weight of adipic acid contained in the additive was applied in 1 part by weight.

<Example 3>

In the same manner as in Example 2, except that 0.5 parts by weight of adipic acid contained in the additive was substituted with 1 part by weight of succinic acid, a waterproof tape having excellent deformation recovery power was prepared.

<Example 4>

A waterproof tape having excellent deformation resilience was prepared in the same manner as in Example 2, except that 0.5 parts by weight of adipic acid contained in the additive was substituted with 1 part by weight of polytetramethylene glycol (weight average molecular weight 2,000).

<Example 5>

A waterproof tape having excellent deformation resilience was prepared in the same manner as in Example 2, except that 0.5 parts by weight of adipic acid contained in the additive was substituted with 1 part by weight of a polyester polyol (weight average molecular weight of 1,000).

<Example 6>

A waterproof tape having excellent deformation resilience was prepared in the same manner as in Example 2, except that 0.5 parts by weight of adipic acid contained in the additive was substituted with 1 part by weight of a polycarbonate polyol (weight average molecular weight of 2,000).

<Example 7>

A waterproof tape having excellent deformation resilience was prepared in the same manner as in Example 2, except that 0.5 parts by weight of toluene diisocyanate and 0.5 parts by weight of isophorone diisocyanate contained in the additive were replaced with 1 part by weight of toluene diisocyanate.

<Example 8>

In the same manner as in Example 2, a waterproof tape having excellent deformation resilience was prepared, except that 1 part by weight of the foaming agent contained in the additive was substituted with 1 part by weight of hollow fine particles (SDI's MFL-7).

<Comparative Example 1>

A waterproof tape was prepared in the same manner as in Example 7 except for excluding 0.5 parts by weight of adipic acid contained in the additive.

<Comparative Example 2>

A waterproof tape was prepared in the same manner as in Example 1, except that 1 part by weight of toluene diisocyanate contained in the curing agent was substituted with 1 part by weight of isophorone diisocyanate.

<Comparative Example 3>

A waterproof tape was prepared in the same manner as in Example 1, except that 0.5 parts by weight of adipic acid contained in the additive was applied in 10 parts by weight.

Evaluation of characteristics of waterproof tape with excellent deformation resilience

<Evaluation of deformation resilience>

2 and 3, the waterproof tape 200 having excellent deformation resilience was cut into 25 mm wide by 10 mm long, laminated to a polyethylene terephthalate film 300 of 100 micrometers, and then cut to become 25 mm wide by 100 mm long. The sample was prepared. Using a 2kg ± 100g Roller, the cut on a SUS304 substrate 100 with a width of 50mm x a length of 120mm x a thickness of 0.8mm, a waterproof tape 200 having excellent deformation restoring power, was compressed to a portion 10mm away from the end of the SUS304 substrate 100. The prepared sample was subjected to a load for 30 seconds at a rate of 10 mm/min at a load of 1 kg to 6 kg, respectively, using a tensile tester (TA instrument), and then allowed to stand at room temperature for 5 minutes. Using a ruler with a scale interval of 0.5 mm, the pushed (restored) distance of the sample was measured. At this time, the starting point for measuring the pushed (restored) distance of the sample is denoted by 400, and the measurement direction of the pushed (restored) distance of the sample is denoted by 500.

<Adhesion and residue evaluation>

Samples to which Examples 1 to 7 and Comparative Examples 1 to 3 were applied were cut into 25 mm wide by 200 mm long and evaluated according to ASTM D3330 standard. After evaluating the adhesion, it was checked whether or not there was an adhesive residue on the adherend, and then marked as none or occurrence.

<Evaluation of impact resistance and separation surface condition>

A waterproof tape having excellent deformation resilience was cut into 48 mm wide by 48 mm long, and then 47.3 mm wide by 47.3 mm long, and a sample with a thickness of 0.7 mm was prepared in a shape that maintains a square shape. Thereafter, a sample was attached on an aluminum (Al) plate of 60 mm in width X 60 mm in length X 6.5 mm in thickness, and then a glass plate of 50 mm in width X 50 mm in length X 2.8 mm in thickness was attached to prepare a sample. The prepared sample was allowed to stand at 24° C. for 30 minutes and then freely dropped by 1.5 m. The aluminum plate and the glass plate were repeatedly dropped until separated. At this time, the number of times of separation was indicated, and no indication was made for the specimens that were cleanly separated from the adherend. Specimens with adhesive residue left on the adherend were marked as Delamination.

<Waterproof function evaluation>

The waterproof tape having excellent deformation resilience was cut into 48 mm in width X 48 mm in length, and then 47.3 mm in width X 47.3 mm in length, and a sample having a thickness of 0.7 mm was prepared in a shape that maintains a square shape. Then, the sample was attached on a polycarbonate (PC) plate having the same size as a 60 mm wide x 60 mm x 6.5 mm thick magnesium (Mg) plate, and then a 50 mm x 50 mm x 2.8 mm thick glass plate was attached. The prepared sample was allowed to stand at 24° C. for 72 hours, and then placed in a water bath filled with 2 m of water, and after 144 hours, the sample was collected to check the presence/absence of leakage. Samples without leakage were marked as Pass and leaked samples were marked as NG.

The results for the above-described evaluations are shown in Table 1 below.

<Table 1>

As shown in Table 1, since the waterproof tapes manufactured through the disclosed Examples 1 to 8 exhibit superior deformation and resilience compared to the waterproof tapes manufactured through Comparative Examples 1 to 3, the shape can be maintained even after impact. Able to know.

In addition, it was confirmed that the waterproof tape manufactured through the disclosed Examples 1 to 8 has improved adhesion and impact resistance compared to the waterproof tape manufactured through Comparative Examples 1 to 3, and no residue was generated, and the waterproof function was also maintained. It was confirmed to be.

Accordingly, the disclosed waterproof tape having excellent deformation recovery power not only has impact resistance and waterproof function, but also has excellent deformation recovery power by including a modified adhesive layer.

10; Base layer
20; Modified adhesive layer
30; Foam adhesive layer
100; SUS304 adherend
200; Waterproof tape with excellent deformation resilience
300; Polyethylene terephthalate film
400; The starting point for measuring the push (recovery) distance of the deformation resilience evaluation
500; Measurement direction of the push (recovery) distance of the deformation resilience evaluation

Claims (8)

Base layer; And
It includes a foamed adhesive layer formed on the upper and lower surfaces of the base layer,
Each of the foamed adhesive layer includes 100 parts by weight of an acrylic resin polymer, 0.1 to 3.0 parts by weight of a foaming agent, 0.5 to 1.5 parts by weight of a curing agent, and 0.5 to 1.5 of an acid additive having a hydroxy group (-OH) or carboxyl group (-COOH) at both ends A waterproof tape consisting of 100 parts by weight and 100 parts by weight of a solvent, and having a thickness of 35 to 135 micrometers and excellent deformation resilience.
The method according to claim 1,
The base layer includes polyethylene terephthalate (PET), and is a waterproof tape having excellent deformation resilience, characterized in that it is formed to a thickness of 9 to 75 micrometers.
The method according to claim 2,
The base layer is formed to a thickness of 15 to 40 micrometers,
The foamed adhesive layer is formed to a thickness of 40 to 110 micrometers, respectively, and is formed to a total thickness of 100 to 300 micrometers, waterproof tape having excellent deformation resilience.
delete The method according to claim 1,
The acid additive is a waterproof tape having excellent deformation resilience, characterized in that it contains at least one selected from the group consisting of adipic acid, succinic acid, polytetramethylene glycol, polyester polyol, and polycarbonate polyol.
The method according to claim 1,
The curing agent is a waterproof tape having excellent deformation resilience, characterized in that it comprises at least one of a toluene diisocyanate curing agent and an isophorone diisocyanate curing agent.
The method according to claim 1,
The acrylic resin polymer is composed of 50 parts by weight of N-butyl acrylate, 40 parts by weight of 2-ethylhexyl acrylate, 5 parts by weight of methyl acrylate, 3 parts by weight of cyclohexyl methacrylate, and 2 parts by weight of acrylic acid,
A waterproof tape having excellent deformation resilience, characterized in that the weight average molecular weight is 400,000 to 900,000.
The method according to claim 1,
The solvent is a waterproof tape having excellent deformation resilience, characterized in that it contains at least one of methyl ethyl ketone, toluene, ethyl acetate, isopropyl alcohol, and xylene.

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