KR102351058B1 - Hot melt adhesive composition - Google Patents

Abstract

The present invention is a styrene-block copolymer as a base resin by including a dicyclopentadiene (DCPD)-based resin and a dicyclopentadiene-C9 (DCPD-C9)-based resin in a specific weight ratio as a tackifier in a hot melt adhesive composition. It relates to a hot melt adhesive composition having good compatibility with and improved softening point and adhesive strength.

Description

Hot melt adhesive composition {HOT MELT ADHESIVE COMPOSITION}

The present invention relates to a hot melt adhesive composition.

Hot melt adhesives are applied by melting by heat, and are widely used as eco-friendly adhesives because the emission of volatile organic solvents is very low. Conventional general-purpose hot melt adhesives are generally constructed by using a thermoplastic polymer such as an olefinic copolymer as a base resin, and adding various waxes as a tackifier or a viscosity modifier.

As the base resin, an olefin-based copolymer such as an ethylene-vinyl acetate copolymer, an ethylene-acrylic acid ester copolymer, or ethylene vinyl acetate, which has advantages of excellent flexibility and low unit cost, is widely used. On the other hand, as a tackifier for improving the adhesive strength, natural resins such as rosin-based resins and terpene-based resins, derivatives thereof, and petroleum resins are widely used. , low molecular weight polyethylene wax, etc. are widely used.

Today, hot melt adhesives are widely used in various fields such as automobiles, packaging containers, structural materials and electronic materials. In this case, the adhesiveness is not sufficient, and the hot melt adhesive using a thermoplastic rubber as the base resin is excellent in heat resistance and cold resistance, but has a problem in that workability is reduced due to high viscosity.

On the other hand, if an excessive amount of a plasticizer is used to reinforce cold resistance or elasticity, phase separation occurs at the operating temperature due to poor compatibility with the base resin, and a bleeding phenomenon occurs, thereby reducing adhesive strength. There is a problem in that sufficient strength and flexibility cannot be expressed.

Meanwhile, in the hot melt adhesive composition, a DCPD (dicyclopentadiene)-based resin or DCPD-C9 (dicyclopentadiene-C9)-based resin is used to increase adhesive strength. On the other hand, in terms of physical properties, a hot melt having high flow properties requires a high softening point to improve heat resistance, and a low viscosity and high adhesion to improve processability. Today, for hot melt adhesives, the demand for low-viscosity, high-flowing hot melts is increasing for ease of processing, and efforts have been made to develop high-flowing hot melt adhesives with excellent adhesion and securing heat resistance.

An object of the present invention is to provide a hot melt adhesive composition having good compatibility between a base resin and a tackifier, high softening point characteristics, and excellent adhesion.

In the present specification, styrene-block copolymer (styrene-block copolymer); and

A dicyclopentadiene (dicyclopentadiene)-based resin and a dicyclopentadiene-C9 (dicyclopentadiene-C9)-based resin are included in a weight ratio of 5: 1 to 1: 5, a tackifier; containing;

An object of the present invention is to provide a hot melt adhesive composition.

In addition, the present invention,

write; and

It is formed on at least one surface of the substrate and is formed by the hot melt adhesive composition, and provides an adhesive member, including an adhesive layer.

In the present invention, terms such as first, second, etc. are used to describe various components, and the terms are used only for the purpose of distinguishing one component from other components.

In addition, the terminology used herein is used only to describe exemplary embodiments, and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present specification, terms such as "comprise", "comprising" or "have" are intended to designate the existence of an embodied feature, number, step, element, or a combination thereof, but one or more other features or It should be understood that the existence or addition of numbers, steps, elements, or combinations thereof, is not precluded in advance.

Also in the present invention, when it is said that each layer or element is formed "on" or "over" each layer or element, it means that each layer or element is formed directly on each layer or element, or other It means that a layer or element may additionally be formed between each layer, on the object, on the substrate.

Since the present invention may have various changes and may have various forms, specific embodiments will be illustrated and described in detail below. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Hereinafter, a hot melt adhesive composition according to a specific embodiment of the present invention will be described in more detail.

According to an example of the present invention, the styrene-block copolymer may include a styrene-butadiene-styrene tri-block copolymer.

And, more specifically, the styrene-block copolymer,

a1) the content of the styrenic unit is 30 to 50 wt%,

a2) the diblock content is from about 50 to about 70% by weight;

a3) The melt flow index measured according to ASTM D1238 may be 70 g/10 min or more.

The hot melt adhesive composition may have a softening point of about 65° C. or higher, preferably about 65 to 75° C., and a high softening point characteristic.

And, at about 160° C., the melt viscosity is about 600 to about 800 cPs, and the viscosity change rate is about 10% or less, which may have low viscosity characteristics.

According to an embodiment of the present invention, the tackifier used in the hot melt adhesive composition is, based on 100 wt% of the total weight of the tackifier, a dicyclopentadiene-based resin and dicyclopentadiene-C9 ( The dicyclopentadiene-C9)-based resin may be included in a ratio of about 25wt%:75wt% to about 75wt%:25wt%.

In addition, the tackifier may be included in an amount of about 200 to about 400 parts by weight based on 100 parts by weight of the styrene-block copolymer.

According to another embodiment of the present invention, the hot melt adhesive composition may further include a plastic oil.

In this case, the plastic oil may be included in an amount of about 50 to about 150 parts by weight based on 100 parts by weight of the styrene-block copolymer.

In addition, according to another aspect of the present invention,

write; and

It is formed on at least one surface of the substrate and is formed by the hot melt adhesive composition, and provides an adhesive member, including an adhesive layer.

write; and

Formed on at least one surface of the substrate and formed by the hot melt adhesive composition according to claim 1, comprising an adhesive layer,

An adhesive member is provided.

At this time, the thickness of the adhesive layer may be about 10 to about 100㎛.

In addition, the adhesive member may have a 180 degree peel strength value of about 5N/in or more, preferably about 8N/in or more, or about 8 to about 12N/in, measured according to ASTM D3330 standard.

The inventors of the present invention use a styrene-block copolymer as a base resin, and a dicyclopentadiene-based resin and a dicyclopentadiene-C9-based resin as a tackifier. When a resin is used, but the dicyclopentadiene-based resin and the dicyclopentadiene-C9-based resin are included in a specific weight ratio, compatibility with the base resin, styrene-block copolymer, is It was excellent, and it was confirmed through an experiment that both the softening point and the adhesive strength were improved, and the present invention was completed.

In general, for a hot melt adhesive composition, it is very important to secure adhesion-related physical properties such as adhesion, adhesion retention, and peel strength according to its use and properties. will vary greatly depending on the composition of

When using an olefin copolymer with low polarity, it is difficult to secure sufficient adhesion, and when a thermoplastic elastic copolymer is used, workability may be reduced due to high viscosity, and when an amorphous alpha olefin copolymer is used However, there is a disadvantage in that the cohesive force is low, and the workability is also poor.

In the case of a styrenic copolymer, it has excellent heat resistance, has excellent processability due to its relatively low viscosity, and has excellent advantages with other components used together, such as tackifiers and plasticizers (oil). Styrene-block copolymers, among others, styrene-butadiene-styrene tri-block copolymers are most preferred.

However, these physical properties may vary depending on the structural characteristics of the styrene-butadiene-styrene triblock copolymer polymer.

From this point of view, the styrene-butadiene-styrene triblock copolymer used in the hot melt adhesive composition according to one aspect of the present invention is,

a1) the content of the styrenic unit is about 30 to about 50 wt%,

a2) the diblock content is from about 50 to about 70% by weight;

a3) It may be preferable to use a melt flow index of about 70 g/10 min or more measured according to ASTM D1238 standard.

In the present specification, among the styrene-butadiene-styrene triblock copolymers, the diblock content refers to a styrene-butadiene-styrene triblock copolymer by conducting a coupling reaction with respect to the styrene-butadiene block copolymer. During the manufacturing process, coupling is not made, so it means the content of the copolymer remaining in the form of a styrene-butadiene diblock.

That is, the styrene-butadiene-styrene triblock copolymer described in the present specification may be in a form including only the styrene-butadiene-styrene triblock because the polymerization reaction and the coupling reaction have completely progressed, and the styrene-butadiene-styrene triblock It may be in the form of a mixture comprising the block, the above-mentioned diblock, and unreacted monomer.

In addition, the content of the diblock in the triblock copolymer, GPC, etc., by measuring the molecular weight distribution of the copolymer, relative to the total weight (100wt%), the styrene-butadiene diblock contained therein (wt%) means the ratio (wt%) .

First, in the styrene-butadiene-styrene triblock copolymer, the content of the styrenic unit may be 30 to 50 wt%, preferably, about 35 to about 50 wt%, more preferably, about 40 to about 45 wt% have.

Since the styrenic monomer has a glass transition temperature (Tg) higher than room temperature, during copolymer polymerization, a hard segment unit having a relatively hard property is formed, and the butadiene monomer has a glass transition temperature value lower than room temperature. , to form a soft segment unit having relatively flexible properties during polymerization of the copolymer.

In consideration of these properties, if the content of the styrenic unit derived from the styrenic monomer is too low, the hardness of the hot melt adhesive composition may be lowered, which may cause a problem of lowering heat resistance, and also, after adhesion and curing, A problem in which mechanical properties are deteriorated may occur.

In addition, when the content of the styrenic unit derived from the styrenic monomer is excessively high, the hardness of the hot melt adhesive composition is increased and the viscosity is also increased, thereby reducing processing properties and lowering the adhesive force may occur.

And, the styrene-butadiene-styrene triblock copolymer has a diblock content of about 50 to about 70% by weight, preferably, about 60 to about 70% by weight, more preferably about 60 to about 65% by weight. can

In the above-described styrene-butadiene-styrene triblock copolymer, when the styrene-butadiene diblock content satisfies the above range, a decrease in viscosity can be clearly observed. can

In addition, when preparing the hot melt adhesive composition, in order to impart high softening point and high flow properties, it is generally necessary to use polyolefin-based additives or to increase the content of these additives. In this case, changes in physical properties other than viscosity occur While problems may occur, in the present application, the above-described styrene-butadiene-styrene tri-block copolymer is used to easily control physical properties such as viscosity, and there is an advantage in that other physical properties do not change.

And, the styrene-butadiene-styrene triblock copolymer has a melt flow index of 70 g/10 min or more, preferably about 70 to about 90 g/10 min, or about 75 to about 85 g/10 min, measured according to ASTM D1238 standard. have.

As the melt flow index of the styrene-butadiene-styrene triblock copolymer, which is the base resin of the hot melt adhesive composition, falls within the above range, the low temperature flowability of the hot melt adhesive composition is improved, and the adhesion and cohesion are improved, It can have excellent processability even at a relatively low temperature.

In preparing the hot melt adhesive composition, a tackifier for imparting tack is used. As a general tackifier, various resins such as rosin-based resin, terpene resin, coumaronindene resin, and petroleum resin have been used, especially Polymerized petroleum resins, such as a dicyclopentadiene type (DCPD) or a dicyclopentadiene-C9 type|system|group (DCPD-C9), or the hydrogenated petroleum resin which added hydrogen to the said petroleum resin was used for the said petroleum resin.

The dicyclopentadiene-based polymeric petroleum resin refers to a petroleum resin produced from C5, ie, cyclopentadiene fraction, produced as a by-product in a naphtha cracking process in which naphtha obtained by refining crude oil is decomposed at a high temperature.

Cyclopentadiene generated in the naphtha cracking process, in most cases, is dimerized and exists in a dicyclopentadiene structure. Interconversion is possible by the reaction, in particular cyclopentadiene can be polymerized to dicyclopentadiene by thermal polymerization or catalytic polymerization.

In addition, the dicyclopentadiene-C9-based polymerized petroleum resin is a polymer resin made by (co)polymerization of the above-mentioned dicyclopentadiene, a C9 fraction containing an aromatic compound, and a C5 fraction containing an aliphatic olefin. it means.

In addition, the hydrogenated petroleum resin is at least a part of the dicyclopentadiene-based polymerized petroleum resin or the dicyclopentadiene-based unit contained in the above-mentioned dicyclopentadiene-C9-based polymerized petroleum resin to dicyclopentadiene, It may mean that hydrogen is added to include dicyclopentane and dicyclopentadiene units.

However, in a hot melt adhesive using a styrene-block copolymer as a base resin, when the above-described dicyclopentadiene (DCPD)-based resin is used as a tackifier, compatibility is lowered, mixing is difficult, and phase separation is not achieved. There was a problem in that it was difficult to secure a uniform adhesive force. In addition, when a dicyclopentadiene-C9 (DCPD-C9)-based resin is used as a tackifier, compatibility with the styrene-block copolymer is improved, so that the hot melt adhesive composition can exhibit a uniform single-phase structure. However, there was a problem in that the softening point was lowered, the heat resistance was lowered, and the adhesive strength was also lowered.

However, in the hot melt adhesive composition according to an aspect of the present invention, the dicyclopentadiene-based resin and the dicyclopentadiene-C9-based resin included as a tackifier are included in the specific ratio described above. , it is possible to improve compatibility with a styrene-block copolymer used as a base resin, and at the same time improve excellent adhesion and excellent thermal stability.

In this regard, the tackifier is, based on the total weight of the tackifier, a dicyclopentadiene-based resin and a dicyclopentadiene-C9-based resin, 25wt%: 75wt% to 75wt% It may be included in a ratio of :25wt%, and other adhesives such as rosin ester may not be included. If too much dicyclopentadiene-based resin is included, there is a possibility of phase separation between the base resin and the tackifying resin at low temperatures due to compatibility problems with the base resin, and dicyclopentadiene-C9 ( When the dicyclopentadiene-C9)-based resin is used excessively, the viscosity of the hot melt adhesive composition increases, the softening point decreases, and thus there may be problems in that adhesion-related physical properties are deteriorated.

In addition, the tackifier may be included in an amount of about 200 to about 400 parts by weight, or about 250 to about 350 parts by weight based on 100 parts by weight of the styrene-block copolymer.

When too little tackifier is included, the tackifying effect is insignificant, and in the hot melt adhesive composition, points and adhesion-related physical properties may not be sufficiently exhibited. The cohesive force is lowered, and again, a problem of lowering adhesion-related physical properties may occur.

From this point of view, the hot melt adhesive composition according to an embodiment of the present invention has one maximum value in the temperature range of about 10 to about 80° C. when measuring the rheological property value (tan theta) according to temperature, a graph of the form can indicate More specifically, for the hot melt adhesive composition, when the storage modulus value (storage modulus, G') and the loss modulus value (G'') were measured according to the temperature change, temperature vs tan theta (G In the graph of ''/G'), there is one maximum value, which means that the compatibility of the hot melt composition is very good, and phase separation does not occur at the corresponding temperature.

And, due to the above-described characteristic composition, the hot melt adhesive composition may have a softening point of about 65° C. or higher, preferably about 65 to 75° C., having a high softening point property.

And, according to another embodiment of the invention, the hot melt adhesive composition, at about 160 ℃, melt viscosity of about 600 to about 800 cPs, preferably about 720 to about 800 cPs, the viscosity change rate is about 10% or less , has low viscosity characteristics, and there is little change in viscosity after aging be able to

According to another embodiment of the present invention, the hot melt adhesive composition may further include a plastic oil, and the plastic oil may include a petroleum-based mineral oil.

Petroleum-based mineral oil is a liquid by-product generated in the process of refining crude oil into petroleum, and is also called liquid paraffin. There is one naphthenic oil, an aromatic oil based on an aromatic hydrocarbon, and in the present invention, petroleum-based mineral oil is a concept including all of the above-mentioned oil and modified oil thereof.

According to an example of the present invention, the petroleum-based mineral oil is preferably paraffinic oil, and white oil modified by hydrotreated and/or dewaxed in the presence of a catalyst, etc. more preferably.

Specifically, paraffinic oil modified by hydrotreating and/or dewaxing is hydrotreated heavy paraffinic distillate (CAS registration number 64742-54-7) or hydrotreated light. Hydrotreated light paraffinic distillate (CAS registration number 64742-55-8), solvent-dewaxed heavy paraffinic distillate (CAS registration number 64742-65-0), solvent-de-waxed Solvent-dewaxed light paraffinic distillate (CAS registration number 64742-56-9), Hydrotreated and dewaxed heavy paraffinic distillate (CAS registration number 91995-39) -0), and hydrotreated and dewaxed light paraffinic distillate (CAS Registration No. 91995-40-3). This is not necessarily limited thereto.

In addition, the plastic oil may be included in an amount of about 50 to about 150 parts by weight, or about 70 to about 130 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene triblock copolymer. If the content of the plastic oil is too small, fluidity and low-temperature processability may be deteriorated, and if the content of the plastic oil is too large, the viscosity may excessively increase and the adhesive performance may be deteriorated.

Meanwhile, in the hot melt adhesive composition according to an embodiment of the present invention, an additional additive may be further included in addition to the above-described base resin and tackifier.

Specifically, according to an embodiment of the present invention, the hot melt adhesive composition includes a plasticizer, a wax, an antioxidant, an elastomer, a pigment, a dye, a filler, a sunscreen agent, an antistatic agent, an antiblocking agent, a slip agent, an inorganic filler, a kneading agent, a stabilizer , a modifying resin, a leveling agent, an optical brightener, a dispersant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, and one or more additives selected from the group consisting of a lubricant may be further included. On the other hand, the materials as described above may be appropriately employed and selected from those common in the art, and are not particularly limited.

For example, in the hot melt adhesive composition, as an antioxidant, pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) (Pentaerythritol tetrakis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate)), tris (2,4-ditert-butylphenyl) phosphite (tris (2,4-ditert-butylphenyl) phosphite), or 2- (2H- A substance such as benzotriazol-2-yl)-p-cresol (2-(2H-benzotriazol-2-yl)-p-cresol) may be further included.

These additives may be included in an amount of about 0.1 to about 10% by weight relative to the total composition in terms of preventing deterioration of adhesion properties, processability, and mechanical properties after adhesion.

In addition, according to another aspect of the present invention,

write; and

It is formed on at least one surface of the substrate and is formed by the hot melt adhesive composition, and provides an adhesive member, including an adhesive layer.

write; and

Formed on at least one surface of the substrate and formed by the hot melt adhesive composition according to claim 1, comprising an adhesive layer,

An adhesive member is provided.

The adhesive member may be in the form of a film or tape, and the substrate may be a film having a laminated structure of one layer or two or more layers.

The base film may be made of paper, glass, or non-woven fabric, but is preferably made of a plastic material. Although it does not specifically limit as such a plastic material, For example, Polyester, such as a polyethylene terephthalate, a polyethylene naphthalate, a polybutylene terephthalate, and a polybutylene naphthalate; polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer; polyvinyl alcohol; polyvinylidene chloride; polyvinyl chloride; vinyl chloride-vinyl acetate copolymer; polyvinyl acetate; polyamide; polyimide; celluloses such as triacetyl cellulose and diacetyl cellulose; fluorine-based resin; polyether; polyetheramides; polyether ether ketone; polyphenylene sulfide; polystyrene-based resins such as polystyrene; polycarbonate; polyether sulfone; Acrylic resins, such as polymethyl methacrylate, etc. are mentioned. In addition, the said material can be used individually or in combination of 2 or more types.

Among them, polyester, cellulose, acrylic resin, etc. may be preferable in consideration of the plastic strength, handleability, cost, dimensional stability, optical properties, and the like.

And, the thickness of the adhesive layer may be from about 10 to about 100 μm, preferably from about 30 to about 70 μm.

According to an embodiment of the present invention, the adhesive member has a 180 degree peel strength value of about 5 N/in or more, preferably about 8 N/in or more, or about 8 to about 12 N/in, measured according to ASTM D3330 standard. Therefore, it can have excellent adhesive properties.

The hot melt adhesive composition described above contains a dicyclopentadiene (DCPD)-based resin and a dicyclopentadiene-C9 (DCPD-C9)-based resin in a specific weight ratio as a tackifier, thereby providing a styrene-block copolymer as a base resin. It has good compatibility with coalescing, and both softening point and adhesive strength are improved. Accordingly, the hot melt adhesive can be widely used in the fields of automobiles, packaging containers, structural materials and electronic materials, in particular, adhesives for hygiene materials.

The hot melt adhesive composition of the present invention may have excellent compatibility with a styrene-block copolymer as a base resin, and high softening point characteristics and excellent adhesion.

1 is a graph of measuring rheological properties according to temperature change for hot melt adhesive compositions according to Examples and Comparative Examples of the present invention.

Hereinafter, through specific examples of the invention, the operation and effect of the invention will be described in more detail. However, these embodiments are merely presented as an example of the invention, and the scope of the invention is not defined thereby.

Styrene-Butadiene-Styrene Tri-Block Copolymer Preparation

5000 g of cyclohexane was put into the high-pressure reactor, 400 g of styrene was added, and the temperature of the reactor was raised to about 60° C. while stirring at about 400 rpm.

As a catalyst, 50 g of n-butyllithium (3 wt% in Cyclohexane) is added and about 5 kgf/cm ² The solution polymerization reaction was carried out while raising the temperature to about 130° C. under pressure.

After the reaction temperature reached 130° C. and after about 5 minutes, it was cooled to 60° C., and 700 g of butadiene was added while maintaining the temperature, and the polymerization reaction was carried out while raising the temperature again to 130° C. under a pressure of ^{about 5 kgf/cm 2 .}

When the coagulation temperature showed the maximum temperature, it was determined that the butadiene reaction was completed in the same way as the styrene reaction.

About 5 minutes after the reaction temperature reaches 130 ° C, a coupling agent (KA-22, manufacturer: Shin-Etsu) of the same equivalent as the n-butyllithium is added, and the reaction proceeds further for 5 minutes, in the triblock air Synthesis was prepared.

Then, about 0.1 g of water was added to terminate the reaction.

In the prepared triblock copolymer, the weight average molecular weight value was 92K, the styrene content was 44.5wt%, and the styrene-butadiene diblock content was 62%, and the MI value measured according to ASTM D1238 was 80g/10min, ASTM D3616 The toluene solution viscosity value measured according to the standard was about 6.31 mm ² /s.

tackifier

As a DCPD-based resin, KOLON's SU-100S product was used, and as a DCPD-C9-based resin, KOLON's SU-400 product was used.

hot melt adhesive composition

In a lL glass beaker, put the white mineral oil, Kaydol (Sonneborn), the tackifier, antioxidant, Irganox 1010, stabilizer, Irgafos 168, UV absorber, Tinuvin P (above, BASF) as plastic oil in a glass beaker, 150 It was heated in a convection oven at ℃ for about 30 minutes. Then, a glass beaker was fixed to a heating mantle at 150° C. and stirred at 100 rpm. After the temperature inside the beaker reached 150° C., the speed was increased to 150 rpm to further stir.

Here, the styrene-butadiene-styrene triblock copolymer was slowly added dropwise and stirred at a speed of 200rpm for 4 hours to completely dissolve the styrene-butadiene-styrene triblock copolymer, thereby preparing a hot melt adhesive composition.

The composition of the hot melt adhesive composition is shown in Table 1 below.

(Unit: parts by weight) Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 styrene block copolymer 20 20 20 20 20 tackifier
(DCPD, softening point 100℃) 18 30 42 60 - tackifier
(DCPD-C9, softening point 105℃) 42 30 18 - 60 plastic oil
Kaydol 19 19 19 19 19 Irganox 1010 0.6 0.6 0.6 0.6 0.6 Irgafos 168 0.2 0.2 0.2 0.2 0.2 Tinuvin P 0.2 0.2 0.2 0.2 0.2 Total 100 100 100 100 100

Experimental example

For the hot melt adhesives according to Examples and Comparative Examples, properties were measured through the following methods, respectively, and the results are summarized in Table 2.

1) Softening point : Measured using ASTM E 28 Ring & Ball test method.

2) Adhesion : It was measured using the 180° peel28 Ring & Ball test method of ASTM D 3330.

3) Compatibility : After mixing, it was observed with the naked eye, and when it was transparent, when it was opaque, it was marked with X.

3-1) compatible (rheological properties) were determined using a TA's G2 ARES (Advanced Rheometrics Expansion System). After the adhesive was collected between the release papers, it was heated at 180° C. for about 2 minutes while being pressed between the glass slides. Before measuring the sample, the cooler was turned on and preheated for about 1 hour, and an atmosphere of nitrogen and air was created at the same time. The measurement was carried out while the temperature was lowered from 120°C to -60°C at a rate of 5°C/min.

The measurement results are shown in FIG. 1 .

4) Viscosity measurement : About 10 g of the hot melt adhesive composition was placed in a sample chamber, and the viscosity was measured at 160° C. for 30 minutes using a Brookfield viscometer (DV2+ Model, Spindle Number 27). .

Thereafter, the hot melt adhesive composition was left under the same conditions for 24 hours, and then the viscosity was measured in the same manner to calculate the viscosity reduction rate. (Related standard: ASTM D4402)

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Softening Point (℃) 73.3 73.8 71.9 77.9 62.7 Adhesion (SUS) (M/in) 10.4 9.4 8.1 12.4 4.3 compatibility Ⅹ 160℃ Viscosity (cPs)
(Viscosity change rate, %) 780
(8.5) 725
(9.3) 730
(9.1) 510
(15.1) 850
-

Referring to Table 2, in the case of the hot melt adhesive composition comprising the DCPD-based resin and the DCPD-C9-based resin in a specific weight ratio as in the Examples of the present invention, the softening point compared to the case of using DCPD-C9 alone (Comparative Example 2) , increased by about 9 to about 10 ° C, exhibiting high softening point characteristics, and it was clearly confirmed that the adhesive strength was improved by about 100%. It was very small, and it was clearly confirmed that excellent adhesion stability could be implemented.

In addition, when only the DCPD-based resin was used alone, a problem occurred in compatibility with the base resin, and it was clearly confirmed that the optical properties were lowered.

1 is a graph of measuring rheological properties according to temperature change for hot melt adhesive compositions according to Examples and Comparative Examples of the present invention.

Referring to FIG. 1, in the case of Comparative Example 1, it can be seen that peaks occur at a temperature of about 55°C and a temperature of about 20°C, respectively, which, while cooling, are performed between the DCPD-based resin and the base resin. It can be seen as an experimental result that clearly supports that compatibility problems may occur.

However, in the case of the hot melt adhesive composition according to the embodiment of the present application, it can be seen that, despite the use of the same DCPD-based resin and the base resin, a major problem in compatibility did not occur, which is a DCPD-based resin and a DPCD-C9-based resin. It is thought to be due to the characteristic of using in a specific ratio.

Claims (12)

styrene-block copolymer; and
A dicyclopentadiene (dicyclopentadiene)-based resin and a dicyclopentadiene-C9 (dicyclopentadiene-C9)-based resin are included in a weight ratio of 5: 1 to 1: 5, a tackifier;
The styrene-block copolymer comprises a styrene-butadiene-styrene tri-block copolymer,
Hot melt adhesive composition.
delete According to claim 1,
The styrene-block copolymer is
a1) the content of the styrenic unit is 30 to 50 wt%,
a2) the diblock content is 50 to 70% by weight,
a3) a melt flow index of at least 70 g/10 min, measured according to ASTM D1238;
Hot melt adhesive composition.
According to claim 1,
A softening point of 65°C or higher;
Hot melt adhesive composition.
According to claim 1,
At 160°C, the melt viscosity is 600 to 800 cPs, and the viscosity change rate is 10% or less.
According to claim 1,
relative to the total weight of the tackifier,
Dicyclopentadiene (dicyclopentadiene)-based resin and dicyclopentadiene-C9 (dicyclopentadiene-C9)-based resin, including 25wt%: 75wt% to 75wt%: 25wt% in a ratio of,
Hot melt adhesive composition.
According to claim 1,
The tackifier is included in an amount of 200 to 400 parts by weight based on 100 parts by weight of the styrene-block copolymer,
Hot melt adhesive composition.
According to claim 1,
A hot melt adhesive composition, further comprising a plastic oil.
9. The method of claim 8,
The plastic oil is included in an amount of 50 to 150 parts by weight based on 100 parts by weight of the styrene-block copolymer,
Hot melt adhesive composition.
write; and
Formed on at least one surface of the substrate and formed by the hot melt adhesive composition according to claim 1, comprising an adhesive layer,
no adhesive.
11. The method of claim 10,
The adhesive layer has a thickness of 10 to 100 μm, an adhesive member.
11. The method of claim 10,
An adhesive member having a 180 degree peel strength value of 5N/in or higher according to ASTM D3330 standard.

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