KR101947723B1 - Adhesive with improved heat-resistance & adhesive strength, a method of manufacturing the same - Google Patents

Abstract

The present invention relates to a pressure-sensitive adhesive improved in heat resistance and adhesion and a method for producing the pressure-sensitive adhesive, and more particularly, to a pressure-sensitive adhesive improved in environment-friendly heat resistance and adhesive strength,
The present invention provides a method for producing a synthetic polymer, comprising the steps of: preparing a synthetic polymer by adding silica or silane at a weight ratio of 8 to 9.5: 0.5 to 2 to a styrene-based elastomer without adding an organic solvent; A second step of adding 2 to 8 parts by weight of a reaction initiator to 100 parts by weight of the synthetic polymer to prepare a first product; A third step of preparing a secondary product by adding 80 to 120 parts by weight of a tackifier to 100 parts by weight of the primary product; Based on 100 parts by weight of the second product by the addition section 1-4 weight adhesion promoter fourth step of producing a third-order products; including, but, in the first step, a styrene-based elastomer in a state filled with nitrogen (N ₂₎ gas Which is obtained by mixing silica or silane while stirring the silica or silane, and a process for producing the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a pressure-sensitive adhesive having improved heat resistance and adhesive strength, and a method of manufacturing the pressure-

The present invention relates to a pressure-sensitive adhesive improved in heat resistance and adhesion and a method for producing the pressure-sensitive adhesive, and more particularly, to a pressure-sensitive adhesive improved in environment-friendly heat resistance and adhesive strength,

In general, materials used to bond two objects together are called adhesives, and oily adhesives are mainly used.

However, when the oil-based adhesive is used, the solvent contained in the oil-based adhesive is discharged into the air, thereby causing the symptoms such as headache, bronchial irritation, cough, itching, dizziness, fatigue and concentration deterioration. , But it is not yet quickly replaced.

In other words, due to the pollution caused by organic compounds and various environmental harmful substances generated in the place where the conventional oil-based adhesive is used, many attempts have been made to replace them, but it is possible to replace the heat resistance and strong adhesive force It means that there is no adhesive.

On the one hand, water-based adhesives appeared to replace volatile adhesive agents. However, since water-based adhesives have a high heat-resistant temperature, they are weak in cohesion and weak in adhesion, and the mediator of the crosslinking reaction is water. There is a disadvantage that metal is often rusted when it is used for metal bonding.

Although the water-based adhesive may have a simple adhesive property, it does not possess a strong adhesive force, a heat-resistant temperature and a heat-retaining ability, and thus has a technical limitation.

Unlike these adhesives, the pressure sensitive adhesives can be adhered to two objects, which is reusable. However, it has a disadvantage in that heat resistance and adhesiveness are weak.

The styrene-based elastomer is mainly used for producing the pressure-sensitive adhesive. In order to secure the fluidity at the temperature at which the styrene-based elastomer is not carbonized, process oil or chromogein has been added. However, As it is designated as a substance causing environmental pollution such as pollution, pollution, and emission.

In addition, since the conventional pressure sensitive adhesive is directly applied on the adherend, it is difficult to apply the pressure sensitive adhesive when it is applied in a liquid phase and to apply the hardener separately.

Accordingly, it is urgent to develop a pressure-sensitive adhesive technology that not only has an adhesive strength as an oil-based adhesive but also is environmentally friendly, has a shortened working time, convenience, cost reduction, excellent adhesive property and compatibility.

Korean Patent Registration No. 10-0297587, May 23, 2001.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above problems, and it is an object of the present invention to provide a pressure-sensitive adhesive having improved heat resistance and adhesive strength while maintaining a heat-

According to an aspect of the present invention, there is provided a method for producing a synthetic polymer, comprising the steps of: preparing a synthetic polymer by adding silica or silane at a weight ratio of 8 to 9.5: 0.5 to 2 to a styrene elastomer without adding an organic solvent; A second step of adding 2 to 8 parts by weight of a reaction initiator to 100 parts by weight of the synthetic polymer to prepare a first product; A third step of preparing a secondary product by adding 80 to 120 parts by weight of a tackifier to 100 parts by weight of the primary product; And a fourth step of adding 1 to 4 parts by weight of an adhesion promoter to 100 parts by weight of the secondary product to prepare a tertiary product. In the first step, the nitrogen (N ₂ ) And the silica or the silane is mixed with the styrene-based elastomer while stirring. The present invention also provides a method for producing a pressure-sensitive adhesive having improved heat resistance and adhesion.

Preferably, the styrene elastomer in the first step is at least one of styrene-isoprene-styrene (SIS), styrene-butadiene-styrene (SBS), and styrene-ethylene-butylene-styrene .

Preferably, in the second step, at least one of at least one of LPO, benzoyl peroxide (BPO) and azobisisobutyronitrile (AIBN) is reacted at 175 to 185 캜. And an initiator is added to the reaction mixture.

Preferably, in the third step, at least one tackifier of C5 petroleum resin, C9 petroleum resin, C5 / C9 copolymer resin, phenol resin, hydrogenated resin, terpene resin and rosin ester resin is added at 140 to 160 ° C And the reaction is carried out.

In order to achieve the above object, the present invention also provides a pressure-sensitive adhesive improved in heat resistance and adhesion, which is produced by the above-described production method.

The present invention has the following effects.

First, since the existing oil-based adhesive needs to be directly applied by hand, the product is likely to be contaminated, which requires a wide working space, requires a drying time and a curing time, Since the drying process is not necessary, a wide work space is not required and the bonding speed is also fast.

Secondly, the existing oil-based adhesive is not easy to store because it hardens when exposed to air, while the pressure-sensitive adhesive of the present invention is used as a finished product, so it is easy to store, and the cost is reduced through automation of the production line It has an effect of increasing productivity.

Thirdly, the environmentally harmful substances are harmful to existing oil-based adhesives, while the environmentally harmful substances are harmless to the human body since the environmentally harmful substances are not used in the pressure-sensitive adhesive of the present invention.

Fourthly, different pressure sensitive adhesives have to be applied to each substrate material, but the pressure sensitive adhesive of the present invention is capable of producing various products based on compatibility with various substrates.

1 shows the adhesion theory.
Figure 2 shows the physical properties of the adhesive tape.
3 is a graph showing the effect on the physical properties of the pressure-sensitive adhesive according to the crosslinking density.
4 is a flowchart according to a preferred embodiment of the present invention;
5 is a product example according to a preferred embodiment of the present invention.
6 is a photograph of heat resistance test according to a preferred embodiment of the present invention.

Prior to describing the present invention, Fig. 1 is an adhesion theory. Referring to FIG. 1, it can be seen that the adhesive tape is a chemical bonding, a physical bonding, and a mechanical bonding.

That is, the chemical bonding (primary bonding) shown in FIG. 1- (a) is a method in which a chemical reaction occurs on the surface between the adherend and the pressure sensitive adhesive and is bonded by chemical bonding. (Secondary bonding) is a method in which the adhesive is pulled together by an attractive force between molecules due to an intermolecular force at the interface between the adherend and the adhesive, and the mechanical coupling (anchor effect) shown in FIG. It is the way in which the adhesive is infiltrated and the two are joined together like a nail on a tree.

The adhesive strength of the adhesive tape is determined by the following characteristics: (1) the properties of the adhesive itself (classified as a soft adhesive and a hard adhesive according to physical properties, or classified by the type of adhesive according to chemical composition) , ③ surface energy, ④ surface texture (roughness of surface), ⑤ contamination degree of adhered material, ⑥ organic solvent, moisture, ultraviolet ray, ⑦ plasticizer transition (soft PVC, rubber), ⑧ out-gassing (polycarbonate) And dispersion.

Figure 2 shows the physical properties of the adhesive tape. As shown in FIG. 2, the physical properties of the adhesive tape include key strength, initial tack, adhesion, and cohesion.

First, the throwing force refers to the bonding strength between the substrate (support) and the pressure-sensitive adhesive.

Second, initial adhesion refers to wettability with the adherend, which is also referred to as surface adhesion. That is, easiness in attaching a pressure-sensitive adhesive to a substrate or an adherend.

Third, the adhesive force refers to the peel strength, which refers to the bonding force at the interface between the adherend and the adhesive. Adhesive force is a standard for adhesion on the adherend, and depends on the magnitude of the viscoelastic change energy of the adhesive.

Fourth, the cohesive force refers to the shear strength or the internal strength of the material, which means the force to which the adhesive itself intends to coalesce. Such cohesion may vary depending on crosslinking, molecular weight, and the like.

3 is a graph showing the effect of the density of crosslinking on the physical properties of the pressure-sensitive adhesive. Referring to FIG. 3, it can be seen that the effect on initial tack, adhesion, and cohesion of three basic physical properties of the pressure-sensitive adhesive according to the crosslink density is shown.

As shown in FIG. 3, as the crosslinking density increases, the initial cohesive force decreases and the compatibility with the adherend decreases. As the cohesive force increases, the pressure-sensitive adhesive becomes harder, the heat-resistant temperature increases, The adhesive is broken after a certain increase.

That is, when the heat-resistant temperature is high, the crosslinking density is high and the cohesive force is increased, which means that the pressure-sensitive adhesive is not elastic and hard, which means poor compatibility with the adherend.

On the contrary, as the crosslinking density decreases, the initial cohesion increases and the compatibility with the adherend increases, but as the cohesion decreases, the pressure sensitive adhesive softens, the heat resistance decreases, and the cohesion decreases.

That is, when the heat-resistant temperature is low, the initial cohesion is increased, but the cohesion is decreased, and the pressure-sensitive adhesive is softened, and the compatibility with the adherend is good.

In this way, when one of the three major physical properties of the pressure-sensitive adhesive is changed, it is difficult to change the physical properties while maintaining the constant heat-resistance temperature. Accordingly, the present invention intends to propose a new technique for producing a pressure-sensitive adhesive having a high heat-resistant temperature while being soft and having good compatibility and high adhesive strength.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is a flowchart according to a preferred embodiment of the present invention. As shown in FIG. 4, a method of manufacturing a pressure sensitive adhesive having improved heat resistance and adhesive strength may be performed through a first step (S10), a second step (S20), a third step (S30), and a fourth step (S40) have.

First, the first step is to synthesize a synthetic polymer by mixing silica or silane at a weight ratio of 8 to 9.5: 0.5 to 2 to the styrene elastomer. (S10)

That is to say, the first step is a step of synthesizing a synthetic polymer having elasticity so that a force that can be held when the finished adhesive is adhered to the adherend is applied. First, the reactor is preheated to 165 to 175 ° C. The reason for preheating before starting the reaction is to shorten the melting time of the styrene elastomer. When the styrene elastomer is melted while stirring the styrene elastomer without preheating, the melting time is prolonged and the ineffective aspect of the process is highlighted I could.

The preheating temperature below 165 ° C was insignificant to shorten the melting time of the styrene elastomer. When the preheating temperature exceeded 175 ° C, the preheating temperature did not show any particular difference compared with the case where the preheating temperature was lower than 165 ° C. It has been found preferable to preheat to a temperature range of 165 to 175 DEG C (most preferably 170 DEG C).

The styrene-based elastomer is added to the preheated reactor and melted for 1 hour and 30 minutes to 2 hours and 30 minutes with stirring. That is, the styrene-based elastomer is put into a reactor preheated at 165 to 175 ° C and melted for 1 hour and 30 minutes to 2 hours and 30 minutes while stirring. When the mixture is stirred for less than 1 hour and 30 minutes, the styrene- Is not well reacted, and if stirring is conducted for more than 2 hours 30 minutes, the physical properties of the styrene-based elastomer may deteriorate. Therefore, it is preferable to melt while stirring for 1 hour 30 minutes to 2 hours 30 minutes.

At this time, the styrene elastomer may be at least one of styrene-isoprene-styrene (SIS), styrene-butadiene-styrene (SBS), and styrene- ethylene- Isoprene-styrene (SIS) was used.

Thereafter, silica or silane is added to the molten styrene elastomer at a weight ratio of 8 to 9.5: 0.5 to 2, followed by mixing for 20 to 40 minutes to prepare a melted synthetic polymer. Here, the silica or silane is initially in a solid state, and is polymerized with the styrene-based elastomer to complete the synthetic polymer.

The reason for adding silica or silane to the styrene elastomer is that the styrene elastomer is firmly held to improve the adhesion of the pressure-sensitive adhesive to the coated surface of the adherend.

Silicone-based silica or silane, in particular, is superior to conventional monomers in terms of (1) thermal stability, (2) adhesion retention that can be maintained for a long time after being adhered to the adherend, and (3) Since the polymer has a soft property and is excellent in compatibility with the adherends, the present invention is applied to the present invention.

In the past, silica or silane was dissolved in an organic solvent such as toluene to prepare an adhesive. However, silica or silane was stuck to the styrene elastomer to react with no solvent, which is a reason for applying the present invention.

Accordingly, in the present invention, by reacting the styrene-based elastomer with silica or silane, the synthetic polymer can be softened and the effect of allowing it to be well impregnated to the adherend can be exhibited.

The silane may be selected from alkoxysilane, acetoxysilane, halogen silane and the like, but not limited thereto. Any silane which can firmly hold the styrene elastomer and control the adhesion of the pressure-sensitive adhesive may be used .

If the amount of the styrene-based elastomer is less than 8 parts by weight, silica or silane should be added in a large amount, so that the solid state silica or silane may take a long time to melt and the adhesive may become too sticky. Or the amount of silane to be added becomes too small, so that the polymerization reaction with the styrene-based elastomer is insufficient and the reaction initiator may not be able to perform the initiation reaction properly.

In the same sense, if the amount of silica or silane is less than 0.5 part by weight, the amount capable of reacting with the styrene elastomer is too small to soften the synthetic polymer. If the amount exceeds 2 parts by weight, the silica or silane may take a long time to melt, In addition, the high price of silica or silane leads to price competitiveness.

However, in the first step, the elasticity of the synthetic polymer can be maintained by mixing the silica or silane with the styrene elastomer while stirring the N ₂ gas 1 to 4 times.

Next, in the second step, 2 to 8 parts by weight of a reaction initiator is added to 100 parts by weight of the synthetic polymer at 175 to 185 캜 to prepare a primary product. (S20)

The second step is an important step in the present invention, and is an intermediate step for producing the pressure-sensitive adhesive using only the synthetic polymer and the tackifier without using any organic solvent or oil that generates environmentally harmful substances.

That is, the second step is to solve the problems caused by the environmentally harmful substances and heavy metals from the existing oil-based adhesives. It does not need to be dissolved with organic solvent or oil, and the synthetic polymer and lauroyl peroxide (LPO) It is possible to produce an environmentally friendly pressure sensitive adhesive which does not generate VOCs by reacting with at least one reaction initiator among benzoyl peroxide (BPO), azo isobutyronitrile (AIBN) and azobisisobutyronitrile.

In the second step, a starting reaction is initiated by introducing a small amount of a reaction initiator into a synthetic polymer in which silica or silane is mixed with the styrene-based elastomer, thereby maximizing the compatibility between the synthetic polymer and the tackifier , It is possible to secure the fluidity of the pressure-sensitive adhesive even if no organic solvent or oil is added. This is possible because the reaction initiator cleaves the high number average molecular weight of the synthesized polymer synthesized in the first step and smoothly changes the synthetic polymer structure to a line.

In other words, as a reaction initiator contributing to enhance the tensile strength and heat resistance is added to the reactor in which the synthetic polymer is formed, the polymerization reaction of the silica or silane dispersed evenly in the styrene-based elastomer starts, and the reactor containing the styrene-based elastomer The fluidity of the internal materials is improved, so that no organic solvent or oil is used in the present invention.

Particularly, in order to increase the heat-resistant temperature, the cohesive force must be controlled, which means that the viscosity should be controlled. However, it has been pointed out that the viscosity of the pressure-sensitive adhesive to be finally obtained can not be attained by increasing the heat-resistant temperature, and the viscosity of the pressure-sensitive adhesive is controlled by using only the reaction initiator without adding organic solvent or oil .

The pressure-sensitive adhesive is not elastic and hardened when the heat-resistant temperature is raised. However, in the present invention, the pressure-sensitive adhesive can be supplied with a reaction initiator so that the heat resistance temperature is maintained, do.

By using such a reaction initiator, the polymerization with the synthetic polymer can convert the circular polymer to a benzene structure having a small molecular size, thereby enhancing heat resistance, retention, and cohesion.

In addition, in the second step, it is preferable to add a reaction initiator to the synthetic polymer of the reactor at 175 ° C to 185 ° C, and if the reaction initiator is reacted at less than 175 ° C, the initiation reaction with the synthetic polymer does not occur properly , Reaction of the reaction initiator at a temperature exceeding 185 ° C causes the synthetic polymer to be deformed rather than to cause deterioration of the physical properties. Therefore, it is preferable to react the reaction initiator at 175 to 185 ° C.

However, if the reaction initiator is added in an amount of less than 2 parts by weight based on 100 parts by weight of the synthetic polymer, it is difficult to maximize the compatibility between the synthetic polymer and the tackifier in the future. If the reaction initiator is added in an amount exceeding 8 parts by weight, It is preferable that the reaction initiator is included in an amount of 2 to 8 parts by weight based on 100 parts by weight of the synthetic polymer since residual properties are lost to deteriorate the physical properties of the finally completed pressure sensitive adhesive.

Next, in the third step, 80 to 120 parts by weight of a tackifier is added to 100 parts by weight of the primary product to prepare a secondary product.

Specifically, in the third step, the tackifier is added so that the adhesive force is exerted on the finally completed pressure-sensitive adhesive. When the reaction of the reaction initiator is completed, the temperature of the reactor is adjusted to 140 to 160 ° C, 80 to 120 parts by weight of at least one of a petroleum resin, a C9 petroleum resin, a C5 / C9 copolymer resin, a phenol resin, a hydrogenated resin, a terpene resin and a rosin ester resin was added and stirred for 30 minutes to 1 hour and 30 minutes to obtain 2 To obtain a tea product.

More specifically, 80 to 120 parts by weight of the tackifier is first added to 100 parts by weight of the primary product in the reactor adjusted to 140 to 160 ° C, and the mixture is stirred for 30 minutes to 1 hour and 30 minutes to obtain a secondary product.

After the third step, the reactor is maintained at a temperature of 140 to 160 DEG C, and 100 parts by weight of the secondary product is added with the C9 petroleum resin, C5 / C9 copolymer resin, phenol resin, hydrogenated resin, terpene resin and rosin ester resin One or more of them may be added in an amount of 2 to 8 parts by weight, and the mixture may be stirred for 20 to 40 minutes to prepare a 2a product. In this case, it is preferable to add a repacking agent other than the tackifier added in the third step.

For example, if the C5 petroleum resin is used as the tackifier in the third step, as described above, as the tackifier in the step 3a, the C9 petroleum resin excluding the C5 petroleum resin, the C5 / C9 copolymer resin, the phenol resin, , A terpene resin, and a rosin ester resin may be used.

Particularly, the reason for obtaining the secondary products and the secondary products in order is to improve the physical properties of the pressure-sensitive adhesive by making the components constituting the pressure-sensitive adhesive to react more uniformly. When the pressure-sensitive adhesive is divided and reacted, There is an effect that the reaction force is uniformly uniform.

However, in the third step, 80 to 120 parts by weight of the tackifier is added to 100 parts by weight of the primary product in a state where the N ₂ gas is filled 1 to 4 times so as to prevent oxidation of the tackifier .

Finally, in the fourth step, 1 to 4 parts by weight of an adhesion promoter is added to 100 parts by weight of the secondary product to prepare a tertiary product.

In the fourth step, the titanium-based (for example, titanium chelate) or phosphorus (for example, phosphoric acid monoalkyl (meth) acrylate) is added to 100 parts by weight of the secondary product while maintaining the temperature of the reactor, ) 1 to 4 parts by weight of an adhesion promoter is added, and after agitation is completed, natural aging is performed to complete the pressure-sensitive adhesive.

If the amount of the tackifier is less than 1 part by weight, the tackifier may exhibit insufficient adhesion. If the tackifier is more than 4 parts by weight, the tackifier may cause instability. Therefore, By weight.

The reason for natural aging after the stirring is completed is that the finished adhesive is allowed to stand at room temperature to stabilize the physical properties.

In particular, the tensile strength of the pressure sensitive adhesive is related to the surface area. Unlike the case where the ordinary hot melt type pressure sensitive adhesive has a tensile strength of 3 kgf / 25 mm, the pressure sensitive adhesive of the present invention completed through the fourth step has a 180 ° fill The test results showed a value of 5 ~ 10 kgf / 25 mm, indicating excellent adhesion.

5 is a product example according to a preferred embodiment of the present invention. Referring to FIG. 5, it can be seen that the pressure-sensitive adhesive sheet 10 can be manufactured using the pressure-sensitive adhesive of the present invention.

(PE), aluminum, carbon fiber, polyethylene, neoprene, ethylene propylene diene monomer (EPDM), sponge, paper, polyvinyl chloride (PVC) The pressure sensitive adhesive 14 according to the present invention is applied on one of the base materials 12 of PU and the release paper 16 is formed on the pressure sensitive adhesive 14 to complete the product of the pressure sensitive adhesive sheet 10 .

6 is a photograph of heat resistance test according to a preferred embodiment of the present invention. 6 (a) is a photograph after the release paper 16 of the pressure-sensitive adhesive sheet 10 is removed and then the pressure-sensitive adhesive 14 is adhered to the adherend 20 and then exposed at 90 DEG C for 2 hours, - (b) is a photograph of the state after being exposed for 2 hours at 90 ° C in FIG. 6 (a) and then exposed to 95 ° C continuously for 1 hour and FIG. 6 (c) After 1 hour of exposure to 100 < 0 > C for 1 hour.

After the releasing paper 16 of the completed pressure-sensitive adhesive sheet 10 was removed, the pressure-sensitive adhesive 14 was adhered to the adherend 20, and the heat resistance was tested after being exposed at 90 ° C, 95 ° C, and 100 ° C, Are shown in Table 1 below.

Item
(Production speed) sample 1
(3 m / min) sample 2
(4 m / min) sample 3
(6m / min) sample 4
(8 m / min) sample 5
(10 m / min) 90 ° C
2 hour exposure pass pass pass pass pass 95 ℃
1 hour exposure pass pass pass pass pass 100 ℃
1 hour exposure pass pass pass pass pass

As shown in Table 1, when exposed at 90 ° C for 2 hours, raised at 90 ° C to 95 ° C for 1 hour, and heated to 95 ° C at 100 ° C for 1 hour, 12) between the nonwoven fabric and the adhering material 20 did not occur, and the adhesive state was also excellent and the heat resistance was satisfied.

According to the present invention, it is expected that the pressure sensitive adhesives having high heat resistance, strong adhesiveness, environment friendliness and flame retardancy can be manufactured, which is the most problematic in the domestic automobile industry and can satisfy the environmentally friendly and V1 grade flammability .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention may be embodied otherwise without departing from the spirit and scope of the invention.

Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to illustrate them, and the scope of the technical idea of the present invention is not limited by these embodiments.

The scope of protection of the present invention should be construed according to the claims, and all technical ideas within the scope of the claims should be construed as being included in the scope of the present invention.

10: Pressure sensitive adhesive sheet
12: substrate
14: Adhesive
16: release paper
20: adhered material

Claims (5)

A first step of adding a silica or a silane to a styrene elastomer at a weight ratio of 8 to 9.5: 0.5 to 2, without adding an organic solvent, to prepare a synthetic polymer;
A second step of adding 2 to 8 parts by weight of a reaction initiator to 100 parts by weight of the synthetic polymer to prepare a first product;
A third step of preparing a secondary product by adding 80 to 120 parts by weight of a tackifier to 100 parts by weight of the primary product; And
And 4) adding 1 to 4 parts by weight of an adhesion promoter to 100 parts by weight of the secondary product to prepare a tertiary product,
In the first step,
Wherein the silica or the silane is mixed with the styrene elastomer while stirring with nitrogen (N ₂ ) gas while stirring. The method according to claim 1,
The styrene-based elastomer in the first step is a styrene-
Wherein the pressure-sensitive adhesive has at least one of styrene-isoprene-styrene (SIS), styrene-butadiene-styrene (SBS), and styrene-ethylene-butylene-styrene (SEBS). The method according to claim 1,
In the second step,
Characterized in that the reaction is carried out by adding at least one reaction initiator selected from the group consisting of lauroyl peroxide (LPO), benzoyl peroxide (BPO) and azobisisobutyronitrile (AIBN) Wherein the heat resistance and the adhesive strength are improved. The method according to claim 1,
In the third step,
Wherein at least one of a C5 petroleum resin, a C9 petroleum resin, a C5 / C9 copolymer resin, a phenol resin, a hydrogenated resin, a terpene resin and a rosin ester resin is added and reacted under 140 to 160 ° C to heat resistance and adhesion Thereby producing the improved pressure-sensitive adhesive. A pressure-sensitive adhesive improved in heat resistance and adhesive strength, which is produced by the production method according to any one of claims 1 to 4.

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