KR20200082720A - Solvent type adhesive composition improved heat resistance, manufacturing method of the same and adhesive film including the same - Google Patents

Abstract

The present invention relates to a solvent-type rubber adhesion agent composition having an improved heat resistance, a manufacturing method thereof, and an adhesion film comprising the same. An object of the present invention is to provide the solvent-type rubber adhesion agent composition having the improved heat resistance and the manufacturing method thereof. The solvent-type rubber adhesion agent composition according to the present invention may include: 40 to 60 wt% of a styrene block copolymer; 35 to 58 wt% of a tackifying resin; and 0.05 to 5 wt% of a mixture of a heat-reactive phenol formaldehyde resin and a metal halide.

Description

SOLVENT TYPE ADHESIVE COMPOSITION IMPROVED HEAT RESISTANCE, MANUFACTURING METHOD OF THE SAME AND ADHESIVE FILM INCLUDING THE SAME}

The present invention relates to a solvent-type rubber pressure-sensitive adhesive composition and a method for manufacturing the same, and an adhesive film having improved heat resistance, including the same.

The adhesive is a material having viscoelastic properties that can be strongly adhered in a short time with a small pressure. Adhesives are widely used in the electrical and electronics industry, automotive industry, protective film industry, wood composite materials and furniture industry, civil construction industry and coating materials, etc., and the use and importance of adhesives have been highlighted in various aspects with the recent development of the industry. In particular, the adhesive industry for protective films for the surface protection of parts and finished products is mainly composed of synthetic rubber and acrylic adhesives, and is a highly import-dependent industrial sector.

The adhesive is largely classified into rubber-based, hot-melt-based, acrylic-based, and silicone-based materials. Among these, rubber-based adhesives are made of natural and synthetic rubber as raw materials, and since rubber is elastic, it is difficult to express adhesive properties by itself. For this reason, a tackifier must be added.

The synthetic rubber used in the adhesive is mainly a block copolymer (block copolymer) system is used. The block copolymer is a molecule composed of two or more components, and in the middle, there is polybutadiene or polyisoprene, and each block has a polystyrene block at the end. Since it is not compatible, the styrene block serves as a crosslinking point forming a domain. Therefore, since it exhibits higher cohesiveness than natural rubber-based adhesives, it is used as a raw material for fixing double-sided tapes, packaging tapes, and diaper tapes, and is being used as a special adhesive. Since the solubility parameters of polystyrene, polybutadiene and polyisoprene are different, the adhesive using synthetic rubber should be prepared in consideration of the compatibility between the tackifying resin and the block to be added. In general, the aromatic tackifying resin dissolves well on the styrene block, and the aliphatic tackifying resin dissolves well on the rubber.

International application PCT/JP2001/003627 proposed a tackifier obtained by polymerizing a vinyl monomer at 180 to 350°C in order to provide a pressure-sensitive adhesive composition having high adhesion and weather resistance. In addition, Korean Patent Publication No. 10-2006-0046099 proposed a method of containing a cationic surfactant and a perchlorate in a polymer for an adhesive in order to provide an adhesive composition and a film for a surface protective film having excellent antistatic properties.

In order to solve the above problems, the present invention introduces a heat-reactive phenol formaldehyde resin and a metal halide into a rubber adhesive to control the unsaturated bond of the styrene block copolymer and crosslinking between the phenol formaldehyde resin, thereby improving heat resistance. It is an object to provide a solvent-type rubber pressure-sensitive adhesive composition and a method for manufacturing the same.

In addition, an object of the present invention is to provide an adhesive film having improved heat resistance, including the solvent-type rubber adhesive composition.

Solvent-type rubber pressure-sensitive adhesive composition according to an embodiment of the present invention is 40 to 60% by weight of a styrene block copolymer; Tackifying resin 35-58% by weight; And 0.05 to 5% by weight of a mixture of a heat-reactive phenol formaldehyde resin and a metal halide.

At this time, the styrene block copolymer, styrene content of 13 to 30% by weight, diblock (diblock) content of 0 to 29% by weight of styrene-ethylene-butylene-styrene block copolymer 35 to 45% by weight; And 5-15% by weight of styrene-isoprene-styrene block copolymer having a styrene content of 10-26% by weight.

The tackifying resin is at least one selected from the group consisting of hydrogenated dicyclopentadiene-based hydrocarbon resin, C5 hydrocarbon-based resin, C9 hydrocarbon-based resin, hydrogenated rosin-based resin and acrylic resin having a softening point of 80 to 150°C. Can.

The weight ratio of the heat-reactive phenol formaldehyde resin and the metal halide may be 3: 1 to 1:3.

The heat-reactive phenol formaldehyde resin may have a structure in which a terminal portion is substituted with aldehyde, alkoxy or hydroxy while having a number of octylphenol groups.

The metal halide may be one or more selected from the group consisting of zinc oxide, zinc chloride, and magnesium oxide.

In addition, the method of manufacturing a solvent-type rubber adhesive composition according to an embodiment of the present invention is to prepare a synthetic rubber solution by dissolving a synthetic rubber styrene block copolymer and a tackifying resin in a mixed solution of an aromatic organic solvent and an alcoholic organic solvent. To do; Preparing a curing agent solution by dissolving a heat-reactive phenol formaldehyde resin in an aromatic organic solvent or an alcohol organic solvent; And mixing the synthetic rubber solution, the curing agent solution, and a metal halide to prepare a solvent-type rubber adhesive composition.

In addition, the adhesive film according to an embodiment of the present invention may include the solvent-type rubber adhesive composition.

According to an embodiment of the present invention, the solvent-type rubber adhesive composition is a styrene-based thermoplastic rubber styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene-styrene block copolymer (SIS) and the composition of the tackifying resin By introducing a heat-reactive phenol formaldehyde resin and a metal halide into the rubber adhesive having, there is an advantage that heat resistance is improved by controlling the crosslink between the styrene-isoprene-styrene block copolymer and the phenol formaldehyde resin. In addition, the solvent-type rubber pressure-sensitive adhesive composition is manufactured in a solvent type rather than a hot melt type, and thus is easy to manufacture a film having a thickness of a thin film.

1 is a view schematically showing a method of measuring a shear adhesive failure temperature (Shear Adhesion Failure Temperature, SAFT) of an adhesive film according to an embodiment of the present invention.
Figure 2 is a graph showing the results of measuring the shear adhesion failure temperature of the adhesive film according to an embodiment of the present invention.
3 is a graph showing the results of measuring the shear adhesion fracture temperature of the adhesive film according to the comparative example of the present invention.

The present invention may be variously modified and may have various forms, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific disclosure form, and it should be understood that all modifications, equivalents, and substitutes included in the spirit and scope of the present invention are included.

In describing each drawing, similar reference numerals are used for similar components. In the accompanying drawings, the dimensions of the structures are shown to be enlarged than the actual for clarity of the present invention. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from other components. For example, the first component may be referred to as a second component without departing from the scope of the present invention, and similarly, the second component may be referred to as a first component. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the terms "include" or "have" are intended to indicate the presence of features, numbers, steps, actions, components, parts or combinations thereof described herein, one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, actions, components, parts or combinations thereof are not excluded in advance.

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

Solvent-type rubber pressure-sensitive adhesive composition according to an embodiment of the styrene block copolymer; Tackifying resins; Heat-reactive phenol formaldehyde resins; And metal halides.

First, the styrene block copolymer is preferably 40 to 60% by weight, more preferably 50% by weight based on the total weight of the pressure-sensitive adhesive composition. When the content of the styrene block copolymer is less than the above range, the viscosity is too low, resulting in a slip phenomenon, which may deteriorate the initial adhesive strength, and when it exceeds the above range, the viscosity is too high and the leveling property decreases, resulting in an adhesive strength. The problem of deterioration may occur.

As such a styrene block copolymer, it is preferable to use a mixture of styrene-ethylene-butylene-styrene block copolymer (SEBS) and styrene-isoprene-styrene block copolymer (SIS).

The styrene-ethylene-butylene-styrene block copolymer has a linear structure, preferably having a styrene content of 13 to 30% by weight and a diblock content of 0 to 29% by weight. Non-limiting examples of styrene-ethylene-butylene-styrene block copolymers include G-1650, G1652, G1657 from Kraton Polymer. The content of the styrene-ethylene-butylene-styrene block copolymer is preferably 35 to 45% by weight based on the total weight of the pressure-sensitive adhesive composition.

Meanwhile, the styrene-isoprene-styrene block copolymer is a linear triblock copolymer, and preferably has a styrene content of 10 to 26% by weight. Examples of the styrene-isoprene-styrene block copolymer include VECTOR 4111A/4111N of TSRC, but are not limited thereto. The content of the styrene-isoprene-styrene block copolymer is preferably 5 to 15% by weight based on the total weight of the pressure-sensitive adhesive composition, and when the content exceeds 15% by weight, the heat resistance is lowered, which is not preferable.

The tackifying resin is a component added to impart tackiness, and is an amorphous oligomer having a molecular weight of several hundred to thousands, and is a liquid or solid thermoplastic resin at room temperature. The rubber itself has no tackiness, but the fluidity is imparted by the action of the added tackifier resin, so the initial adhesive strength, adhesive strength and holding power are controlled, so the selection of the tackifying resin is very important.

Accordingly, in the present invention, the hydrogenated dicyclopentadiene hydrocarbon resin having a softening point of 80 to 150°C as a tackifying resin (Hydrogenated dicyclopentadiene, DCPD), C5 hydrocarbon resin, C9 hydrocarbon resin, hydrogenated rosin resin, and It is preferable to use at least one selected from the group consisting of acrylic resins.

The rosin system, which is a natural resin system, has low stability because its main component is oxidized because it has a double bond conjugated to abietic acid and its isomers. Therefore, in order to improve it, it is used in the form of denatured rosin stabilized with hydrogenation, heterogeneous reaction, dimer, and the like. Terpene resin, which is a natural resin system, uses terpene oil obtained from pine as a raw material and polymerizes it with a Lewis acid catalyst to obtain terpene resin. Since it is an isoprene polymer, it is widely used because of its excellent compatibility, easy to obtain a balance of adhesive properties with a wide resin concentration range, easy development and design of adhesives, and outstanding tackifying effect at low temperatures.

Aliphatic (C5), aromatic (C9), and dicyclopentadiene (DCPD) systems are mainly used as the synthetic resin system. The aliphatic type is used as a tackifying resin for rubber-based adhesives, so it exhibits good adhesion properties and exhibits stable values, so it is used in large quantities, such as kraft tape. However, since the aromatic system has poor compatibility with a rubber-based adhesive, it is mainly used in a copolymerized form with an aliphatic system. The tackifying resin of the present invention uses a hydrogenated dicyclopentadiene hydrocarbon resin having a softening point of 40 to 150°C to impart adhesive performance to synthetic rubber. It is particularly preferable to use a hydrogenated dicyclopentadiene hydrocarbon resin having a softening point of 80 to 150°C in terms of initial adhesion and peel strength.

Specific examples of the aliphatic hydrocarbon resin, A-1100, A-1100S, A-1115, C-1100, C-100W, C-115R, H-2100, H-2110, H-2120, H-2130, H- 2140 H-2200, H-2300, R-1100, T-1080, T-1095, and the like, and non-limiting examples of hydrogenated dicyclopentadiene-based hydrocarbon resins include the SUKOREZ series of KORON INDUSTRY, SU-90, SU-500, SU-525, SU-640, etc. are particularly preferred.

On the other hand, the physical properties of the pressure-sensitive adhesive vary depending on the content of the tackifying resin, and particularly, the initial adhesive strength increases to a certain content, but rapidly decreases at a certain content or more. Considering the physical properties of the initial adhesive strength, the content of the tackifying resin is preferably 35 to 58% by weight, more preferably 49 to 50% by weight, based on the total weight of the adhesive composition.

The heat-reactive phenol formaldehyde resin is added to control the crosslinking of an unsaturated bond of a styrene-isoprene-styrene block copolymer, and has a structure in which a terminal portion is substituted with aldehyde, alkoxy or hydroxy while having a large number of octylphenol groups. desirable. At this time, the octylphenol group improves the heat resistance of the pressure-sensitive adhesive composition by increasing the crosslinking ability by combining a phenol formaldehyde resin and a styrene block copolymer. A non-limiting example of such a heat-reactive phenol formaldehyde resin is SP-1045 from SI GROUP INC. In addition, the total content of the heat-reactive phenol formaldehyde resin and the tackifying resin is preferably 40 to 60% by weight, more preferably 50% by weight based on the total weight of the pressure-sensitive adhesive composition.

In addition, the metal halide is preferably at least one selected from the group consisting of zinc oxide, zinc chloride and magnesium oxide.

Here, the total content of the heat-reactive phenol formaldehyde resin and the metal halide is preferably 0.05 to 2% by weight based on the total weight of the pressure-sensitive adhesive composition. In addition, the weight ratio of the heat-reactive phenol formaldehyde resin and the metal halide is preferably 3: 1 to 1: 3, and more preferably 1:1.

On the other hand, the solvent-type rubber pressure-sensitive adhesive composition according to the present invention comprises the steps of preparing a synthetic rubber solution; Preparing a curing agent solution; And preparing a solvent-type rubber pressure-sensitive adhesive composition by mixing a synthetic rubber solution, a curing agent solution, and a metal halide, but is not limited thereto.

First, the step of preparing a synthetic rubber solution may be a step of preparing a synthetic rubber solution by dissolving a synthetic rubber styrene block copolymer and a tackifying resin in a mixed solution of an aromatic organic solvent and an alcohol organic solvent. The aromatic organic solvent and the alcohol organic solvent may be mixed in a weight ratio of 1:9 to 9:1. At this time, the styrene block copolymer and the tackifying resin are the same as described above, and duplicate description will be omitted.

On the other hand, the styrene-ethylene-butylene-styrene block copolymer, when swollen (Sweeling) in a solvent, the solid content is preferably 20% by weight. In addition, when swelling in a solvent, the styrene-isoprene-styrene block copolymer preferably has a solid content of 20% by weight. In the case of tackifying resin, when dissolved in a solvent (Soluble), the solid content is preferably 50% by weight or less. The solvent is used with reference to a solubility parameter, and the aromatic organic solvent is preferably benzene, toluene and xylene, and the alcohol organic solvent is preferably methanol, ethanol and methyl ethyl ketone. Toluene, which is an aromatic organic solvent, is particularly preferably used.

The step of preparing a curing agent solution may be a step of preparing a curing agent solution by dissolving a heat-reactive phenol formaldehyde resin in an aromatic organic solvent or an alcoholic organic solvent. Here, the heat-reactive phenol formaldehyde resin and the organic solvent are the same as described above, and overlapping descriptions will be omitted. On the other hand, in the case of thermally reactive phenol formaldehyde resin, when dissolved in a solvent (Soluble), the solid content is preferably 50% by weight or less.

Thereafter, the step of preparing the solvent-type rubber pressure-sensitive adhesive composition may be a step of preparing a solvent-type rubber pressure-sensitive adhesive composition by mixing a synthetic rubber solution, a curing agent solution, and a metal halide. Here, the concentration of the prepared solvent-type rubber adhesive is preferably 20% by weight. In addition, the metal halide is the same as described above, and duplicate description will be omitted.

The solvent-type rubber pressure-sensitive adhesive composition thus prepared is a styrene-ethylene-butylene-styrene block copolymer (SEBS), a styrene-based thermoplastic rubber, and a rubber pressure-sensitive adhesive having a composition of a tackifying resin and styrene-isoprene-styrene block copolymer (SIS). By introducing a heat-reactive phenol formaldehyde resin and a metal halide, it is characterized in that the heat resistance is improved by controlling the crosslink between the styrene-isoprene-styrene block copolymer and the phenol formaldehyde resin. In addition, the solvent-type rubber pressure-sensitive adhesive composition is manufactured in a solvent type rather than a hot melt type, and thus is easy to manufacture a film having a thickness of a thin film.

On the other hand, the pressure-sensitive adhesive obtained according to the production method of the present invention may be prepared as an adhesive film. At least one side of the adhesive film has an adhesive layer coated with the adhesive of the present invention. The material of the film is not particularly limited, but a polyethylene terephthalate film is most preferred. The thickness of the pressure-sensitive adhesive layer applied to the film is preferably 1 to 100 μm. It is suitable in terms of adhesive strength that the film coated with the adhesive is cured at 90 to 200°C for 3 to 10 minutes.

Hereinafter, the present invention will be described in detail through examples. However, the following examples are only to illustrate the present invention, the present invention is not limited by the following examples.

[Example 1]

40% by weight of styrene-ethylene-butylene-styrene block copolymer (G1650), 10% by weight of styrene-isoprene-styrene block copolymer (VECTOR 4111N) and 49.8% by weight of hydrogenated DCPD (SU-90) toluene and ethanol Dissolved in a mixed solution of to prepare a synthetic rubber solution. The concentration of the prepared synthetic rubber solution was 20% by weight.

A curing agent solution was prepared by dissolving 0.1% by weight of thermally reactive phenol formaldehyde resin (SP-1045) (1 phr based on SIS content) in a mixed solution of toluene and ethanol. The concentration of the prepared curing agent solution was 50% by weight.

Thereafter, the prepared synthetic rubber solution, curing agent solution, and 0.1% by weight of zinc oxide were blended to prepare an adhesive composition. The concentration of the prepared adhesive composition was 20% by weight.

Subsequently, the prepared pressure-sensitive adhesive composition was applied to three PET films of 75 μm, respectively, and cured at 90° C., 150° C., and 200° C. for 10 minutes, respectively, and then a release film was covered to prepare an adhesive film.

[Examples 2 to 5]

The adhesive films were prepared through the same process as in Example 1, except that the contents of the hydrogenated DCPD, the heat-reactive phenol formaldehyde resin, and zinc oxide were adjusted as shown in Table 1 below.

Example 1 Example 2 Example 3 Example 4 Example 5 Rubber
(wt%) SEBS 40 40 40 40 40 SIS 10 10 10 10 10 Tackifying resin
(wt%) SU-90 49.8 49 48 47 46 Crosslinker
(wt%) SP-1045
(Compared to SIS content) 0.1
(1phr) 0.5
(5phr) 1.0
(10phr) 1.5
(15phr) 2.0
(20phr) ZnO 0.1 0.5 1.0 1.5 2.0

[Comparative Examples 1-1 to 3-2]

Styrene-ethylene-butylene-styrene block copolymer (G1650), styrene-isoprene-styrene block copolymer (VECTOR 4111N) and hydrogenated DCPD (SU-90 or SU-500) are adjusted to the contents shown in Table 2 below. By dissolving it in a mixed solution of toluene and ethanol, an adhesive composition was prepared. The concentration of the prepared adhesive composition was 20% by weight.

Thereafter, the prepared pressure-sensitive adhesive composition was applied to a PET film of 75 μm, respectively, and cured at 90° C. for 3 minutes, respectively, and then a release film was covered to prepare an adhesive film.

Comparative Example 1-1 Comparative Example 1-2 Comparative Example 2-1 Comparative Example 2-2 Comparative Example 3-1 Comparative Example 3-2 Rubber
(wt%) SEBS 45 45 40 40 35 35 SIS 5 5 10 10 15 15 Tackifying resin
(wt%) SU-90 50 - 50 - 50 - SU-500 - 50 - 50 - 50

[Experimental Example]

In order to measure the shear adhesion failure temperature (SAFT) of each of the adhesive films prepared in Examples 1 to 5 and Comparative Examples 1-1 to 3-2, the test piece was held in accordance with ASTM D4498. Chemistry). At this time, as shown in Figure 1, the material of the substrate was made of stainless steel (SUS304), after attaching the specimen to the substrate in a constant area (25mm ⅹ 25mm), 2kg roller was reciprocated twice to prepare a specimen. Thereafter, when a constant heating rate (0.5°C/min) was applied by applying a constant load (1 kg) to the film, the temperature at which the adhesive film fell off the substrate was measured. The measurement results of the examples are shown in FIG. 2, and it was confirmed that the shear adhesion fracture temperature of the adhesive films according to Examples 1 to 5 was improved to 100° C. or higher. On the other hand, the measurement result of the comparative example is shown in Figure 3, it can be seen that the shear adhesive breakdown temperature of the adhesive film decreases as the content of the styrene-isoprene-styrene block copolymer increases, and the shear adhesive breakdown temperature compared to the embodiment. You can see that it is low.

In the above, it has been described with reference to preferred embodiments of the present invention, but those skilled in the art or those of ordinary skill in the art will depart from the spirit and technical scope of the present invention described in the claims below. It will be understood that various modifications and changes may be made to the present invention without departing from the scope.

Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

Claims (8)

40-60% by weight of styrene block copolymer;
Tackifying resin 35-58% by weight; And
A solvent-type rubber adhesive composition comprising 0.05 to 5% by weight of a mixture of a heat-reactive phenol formaldehyde resin and a metal halide. According to claim 1,
The styrene block copolymer,
Styrene-ethylene-butylene-styrene block copolymers having a styrene content of 13 to 30% by weight, and a diblock content of 0 to 29% by weight, 35 to 45% by weight; And
A solvent-type rubber adhesive composition comprising 5 to 15% by weight of a styrene-isoprene-styrene block copolymer having a styrene content of 10 to 26% by weight. According to claim 1,
The tackifying resin is one type selected from the group consisting of hydrogenated dicyclopentadiene hydrocarbon resin, C5 hydrocarbon resin, C9 hydrocarbon resin, hydrogenated rosin resin and acrylic resin having a softening point of 80 to 150°C. Ideal Solvent-type rubber adhesive composition. According to claim 1,
The weight ratio of the heat-reactive phenol formaldehyde resin and the metal halide is 3: 1 to 1:3, the solvent-type rubber adhesive composition. According to claim 1,
The heat-reactive phenol formaldehyde resin has a plurality of octylphenol groups, and the terminal part is a structure in which the terminal is substituted with aldehyde, alkoxy, or hydroxy solvent-type rubber adhesive composition. According to claim 1,
The metal halide is a solvent-type rubber pressure-sensitive adhesive composition selected from the group consisting of zinc oxide, zinc chloride and magnesium oxide. An adhesive film comprising the solvent-type rubber adhesive composition according to any one of claims 1 to 6. Preparing a synthetic rubber solution by dissolving a synthetic rubber styrene block copolymer and a tackifying resin in a mixed solution of an aromatic organic solvent and an alcohol organic solvent;
Preparing a curing agent solution by dissolving a heat-reactive phenol formaldehyde resin in an aromatic organic solvent or an alcohol organic solvent; And
Method for producing a solvent-type rubber pressure-sensitive adhesive composition comprising the step of preparing a solvent-type rubber pressure-sensitive adhesive composition by mixing the synthetic rubber solution, the curing agent solution and a metal halide.

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