KR102112666B1 - Heat resistant rubber adhesive composition and adhesive tape containing the same - Google Patents

Abstract

The present invention relates to a heat-resistant rubber-based pressure-sensitive adhesive composition and a heat-resistant pressure-sensitive adhesive tape comprising the same, and according to the present invention, a heat-resistant rubber-based pressure-sensitive adhesive composition containing natural or synthetic rubber, tackifying resin, polyfunctional thiol compound, initiator and reaction accelerator and the same Provided is a heat resistant tape having excellent heat resistance.

Description

Heat-resistant rubber adhesive composition and heat-resistant adhesive tape containing the same {Heat resistant rubber adhesive composition and adhesive tape containing the same}

The present invention relates to a heat-resistant rubber-based pressure-sensitive adhesive composition and a heat-resistant pressure-sensitive adhesive tape comprising the same, specifically, a specific crosslinking agent is added to the pressure-sensitive adhesive composition to maintain adhesion even at high temperatures, and a heat-resistant pressure-sensitive adhesive composition that does not leave residue on the surface even when removed And it relates to a heat-resistant adhesive tape comprising the same.

The adhesive tape is made by coating an adhesive on the substrate. Since the adhesive tape used in semiconductor or automobile manufacturing processes is used in a high temperature environment, the heat resistance of the adhesive layer and high adhesiveness and adhesive force are required.

On the other hand, the adhesive tape is removed at the end of the process of the product. At this time, when the adhesive layer is transferred to the parts to be adhered, the stability of the process or the reliability of the product is greatly threatened.

However, when a high adhesive strength is required in a series of processes, when the adhesive strength is increased by adjusting the composition, the transfer of the adhesive layer occurs on the contrary.

In order to solve this problem, a method of reducing tape transfer is used by increasing the cohesive force of the adhesive layer. However, when the cohesive force of the adhesive layer is increased, there is a problem that the adhesive force is reduced.

Republic of Korea Patent Publication 10-2005-0117243 (2005.12.14.) Republic of Korea Patent Publication 10-2016-0085215 (2016.07.15)

Therefore, it is an object of the present invention to provide a heat-resistant rubber-based pressure-sensitive adhesive composition that is excellent in adhesion even when used in a high-temperature environment and does not leave a residue on the adhered surface upon removal.

In addition, another object of the present invention is to provide a heat-resistant tape comprising the heat-resistant rubber-based pressure-sensitive adhesive composition.

In order to achieve the above object, according to the present invention, there is provided a heat-resistant rubber-based pressure-sensitive adhesive composition containing natural or synthetic rubber, tackifying resin, polyfunctional thiol compound, initiator and reaction accelerator.

The synthetic rubber includes a double bond in the main chain, and is characterized by being SIS rubber or SBR rubber. The tackifying resin is characterized in that it is a petroleum resin or a reactive phenol resin. The polyfunctional thiol compound is characterized by having two thiol groups.

The thiol compound is 1,3-propanedithiol, 1,4-butanedithiol, 1,4-benzenedimethanethiol, tetra (ethylene glycol) dithiol, hexa (ethylene glycol) dithiol, poly (ethylene glycol) Dithiols, 1,3,4-thiadiazole-2,5-dithiols, toluene-3,4-dithiols, benzene-1,2-dithiols, biphenyl-4,4-dithiols, para- At least one selected from the group consisting of terphenyl-4,4-dithiols and 1,16-hexadecanedithiols can be used.

At this time, it is preferable to contain in a proportion of 80 to 120 parts by weight of the tackifying resin, 1 to 10 parts by weight of the polyfunctional thiol compound, and 1 to 20 parts by weight of the reaction accelerator relative to 100 parts by weight of the natural or synthetic rubber. The heat-resistant rubber-based adhesive composition may further include an inorganic material, a stabilizer, and a softener. The inorganic material used at this time should not exceed 60% by weight in the total formulation.

According to the present invention to achieve the other object, there is provided a heat-resistant tape produced by applying the heat-resistant rubber-based pressure-sensitive adhesive composition to at least one surface of the substrate. Preferably, the substrate is a cotton cloth.

The heat-resistant tape prepared by using the heat-resistant rubber-based adhesive composition according to the present invention has the advantage that the adhesive strength is maintained at a high temperature of 180 ° C. for at least 30 minutes, and a continuous process can be performed without leaving any residue on the surface of the adherend even when removed. .

Hereinafter, the present invention will be described in more detail.

According to the present invention, a heat-resistant rubber-based pressure-sensitive adhesive composition containing natural or synthetic rubber, tackifying resin, multifunctional thiol compound, initiator and reaction accelerator is provided.

The synthetic rubber includes a double bond in the main chain, and SIS rubber or SBR rubber may be used. Among synthetic rubbers used, it is preferable to use SIS rubber having a styrene content of 40% by weight or less, and SBR rubber having a styrene content of 30% by weight or less.

When used in combination with synthetic rubber rather than using natural rubber alone, it is preferable because it has excellent heat resistance and retention under the same conditions. More preferably, the ratio of synthetic rubber 20 to natural rubber 80 is used, and in this case, synthetic rubber may be mixed with SIS rubber and SEBS rubber if necessary.

The tackifying resin may be petroleum resin or reactive phenolic resin, and preferably reactive phenolic resin.

The polyfunctional thiol compound used in the composition forms a crosslink at the double bond site included in the main chain of rubber. Specifically, after forming a radical using a peroxide or persulfide in the unsaturated group of the main chain, it is a technical feature to improve the heat resistance by inducing a reaction with a polyfunctional thiol compound, preferably a thiol compound having a bifunctional group.

The thiol compound is 1,3-propanedithiol, 1,4-butanedithiol, 1,4-benzenedimethanethiol, tetra (ethylene glycol) dithiol, hexa (ethylene glycol) dithiol, poly (ethylene glycol) Dithiols, 1,3,4-thiadiazole-2,5-dithiols, toluene-3,4-dithiols, benzene-1,2-dithiols, biphenyl-4,4-dithiols, para- Terphenyl-4,4-dithiol, 1,16-hexadecanedithiol, and the like can be used alone or in combination. Preferably, 1,3-propanedithiol, 1,4-benzenedimethanethiol, and 1,16-hexadecanedithiol are mainly used.

It is also possible to further include other polythiol compounds.

 Metal oxides can be used together to improve heat resistance.

At this time, the heat-resistant rubber-based pressure-sensitive adhesive composition is based on 100 parts by weight of natural rubber or synthetic rubber, 80 to 120 parts by weight of the tackifying resin, 10 parts by weight or less of the polyfunctional thiol compound, preferably 1 to 10 parts by weight, reaction accelerator 1 to It can be made in a proportion of 20 parts by weight. The heat-resistant rubber-based adhesive composition may further include inorganic substances such as calcium carbonate, cray, and zeolite, stabilizers, and softeners. Through proper formulation of inorganic materials, various physical properties of the adhesive are produced. The inorganic material used at this time should not exceed 60% by weight in the total formulation.

The reaction temperature in preparing the pressure-sensitive adhesive composition depends on the properties of the initiator. Azo-based compounds, peroxides, and persulfide-based materials can be used to generate radicals. As an azo-based compound, AIBN (azobisisobutyronitrile) may be used. The melting point is 103 to 105 ° C, and radicals are generated at 60 ° C or higher. Di-tert-butyl peroxide (DTBP), benzoyl peroxide (BPO), aceton peroxide, methyl ethyl ketone peroxide (MEKP), etc. may be used as the peroxide-based compound. As the persulfate-based compound, ammonium persulfate (APS) or potassium peroxydisulfate (KPS) may be used.

When blending the pressure-sensitive adhesive composition of the present invention, the temperature is preferably determined in the range of 110 to 150 ° C. If possible, it is considered appropriate to use an initiator having a melting point in this range. Those outside the temperature range are also applicable.

Reactive phenolic resins attack the double bonds in the main chain of the rubber when the proper temperature and accelerator are added to cause crosslinking reaction. The advantage of such a crosslinking system is that a polyfunctional thiol compound reacts with radicals generated by the rubber backbone attack of the initiator in the vicinity of 110 to 120 ° C to form a crosslink, and when the process proceeds to 130 ° C or higher, methylol groups in the structure The phenolic resin possessed participates in the reaction to further form a crosslink.

The reaction accelerator generally uses a metal oxide as a material that serves to increase the activity of the target material so that the reaction can proceed stably at a lower temperature. In the present invention, ZnO (zinc oxide), MgO (magnesium oxide), CdO (cadmium oxide), or the like may be used as the metal oxide, and ZnO is preferably used.

In the present invention, unlike the conventional technique, an azo-based, peroxide-based, or persulfide-based initiator is used, and is characterized by crosslinking reaction using a polyfunctional thiol compound and a reactive phenol resin at the same time. Various properties can be adjusted depending on the type of rubber, whether or not a reactive phenolic resin is added, and its input amount, so it has an advantage that it is possible to supply an adhesive tailored to the properties desired by the consumer.

The heat-resistant pressure-sensitive adhesive composition thus prepared is coated on one surface of the substrate to produce a heat-resistant tape. A variety of fibrous sheets may be used as the substrate, and cotton cloth is preferably used. Cotton fabrics can be produced using pure cotton or rayon yarn, pure cotton-rayon mixed yarn, etc., depending on the purpose and process characteristics.

According to one embodiment of the present invention, a coating layer made of an acrylic polymer, a vinyl polymer, an acrylic-vinyl copolymer resin, etc. having heat resistance is formed on the other surface of the substrate on which the adhesive is not coated.

The heat-resistant tape manufactured as described above maintained an adhesive strength of at least 30 minutes even at a high temperature of 180 ° C. or higher, and exhibited excellent properties that no residue remained on the surface of the adherend upon removal.

[Example]

Hereinafter, the present invention will be described in more detail through examples and test examples.

Examples 1 to 16: Preparation of the pressure-sensitive adhesive composition

The pressure-sensitive adhesive composition was prepared according to the compositions of Tables 1 to 16 below. As the mercaptan compound, 1,3-propanethiol, 1,4-benzenedimethanethiol, and 1,16-hexadecanediol having bifunctional groups were used alone or in mixture, and the petroleum resin was C1100 (sp = 100 ℃). , C5 system), A1100 (sp = 100 ° C, C5 system) was used. As the reactive phenolic resin, SP 1045 (a product made by SI and a product containing 9-10% methylol) was used.

division Input (g) Characteristic Natural rubber 50 Tg = -65 ℃ Oil balance 50 Sp = 100 ℃ Mercaptan compounds One  Dithiol Calcium carbonate 100 wonderment ZnO 0.5 Initiator 0.1 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Natural rubber 50 Tg = -65 ℃ Oil balance 50 Sp = 100 ℃ Mercaptan compounds 5 Dithiol Calcium carbonate 100 wonderment ZnO 2.5 Initiator 0.5 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Natural rubber 50 Tg = -65 ℃ Oil balance 50 Sp = 100 ℃ Mercaptan compounds 3 Dithiol Calcium carbonate 100 wonderment ZnO 1.5 Initiator 0.3 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Synthetic rubber 50 SIS, Kraton 411N Oil balance 50 Sp = 100 ℃ Mercaptan compounds One Dithiol Calcium carbonate 100 wonderment ZnO 0.5 Initiator 0.1 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Synthetic rubber 50 SIS, Kraton 411N Oil balance 50 Sp = 100 ℃ Mercaptan compounds 3 Dithiol Calcium carbonate 100 wonderment ZnO 1.5 Initiator 0.3 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Synthetic rubber 50 SIS, Kraton411N Oil balance 50 Sp = 100 ℃ Mercaptan compounds 5 Dithiol Calcium carbonate 100 wonderment ZnO 2.5 Initiator 0.5 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Natural rubber 50 Tg = -65 ℃ Petroleum resin / reactive phenolic resin 49/1 Sp = 100 ℃ / SI Mercaptan compounds One Dithiol Calcium carbonate 100 wonderment ZnO 0.5 Initiator 0.1 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Natural rubber 50 Tg = -65 ℃ Petroleum resin / reactive phenolic resin 47/3 Sp = 100 ℃ / SI Mercaptan compounds 3 Dithiol Calcium carbonate 100 wonderment ZnO 1.5 Initiator 0.3 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Natural rubber 50 Tg = -65 ℃ Petroleum resin / reactive phenolic resin 45/5 Sp = 100 ℃ / SI Mercaptan compounds 5 Dithiol Calcium carbonate 100 wonderment ZnO 2.5 Initiator 0.5 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Synthetic rubber 50 SIS, Kraton411N Petroleum resin / reactive phenolic resin 49/1 Sp = 100 ℃ / SI Mercaptan compounds One Dithiol Calcium carbonate 100 wonderment ZnO 0.5 Initiator 0.1 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Synthetic rubber 50 SIS, Kraton 411N Petroleum resin / reactive phenolic resin 47/3 Sp = 100 ℃ / SI Mercaptan compounds 3 Dithiol Calcium carbonate 100 wonderment ZnO 1.5 Initiator 0.3 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Synthetic rubber 50 SIS, Kraton 411N Petroleum resin / reactive phenolic resin 45/5 Sp = 100 ℃ / SI Mercaptan compounds 5 Dithiol Calcium carbonate 100 wonderment ZnO 2.5 Initiator 0.5 KPS Softener, stabilizer, etc. 1.5 Process oil, UV stabilizer

division Input (g) Characteristic Natural / synthetic rubber 40/10 Tg = -65 ° C / SIS Kraton411N Oil balance 45 SP = 100 ℃ Calcium carbonate 100 wonderment Mercaptan compounds 5 Dithiol Reactive phenolic resin 5 Methylol content 9-10% ZnO 10 accelerant KPS 0.5 Initiator

division Input (g) Characteristic Natural / synthetic rubber 40/10 Tg = -65 ° C / SIS Kraton411N Oil balance 45 SP = 100 ℃ Calcium carbonate 100 wonderment Mercaptan compounds 2.5 Dithiol Reactive phenolic resin 5 Methylol content 9-10% ZnO 7.5 accelerant KPS 0.5 Initiator

division Input (g) Characteristic Natural / synthetic rubber 40/10 Tg = -65 ° C / SIS Kraton411N Oil balance 45 SP = 100 ℃ Calcium carbonate 100 wonderment Mercaptan compounds 5 Dithiol Reactive phenolic resin 5 Methylol content 9-10% ZnO 7.5 accelerant KPS 0.5 Initiator

division Input (g) Characteristic Natural / synthetic rubber 40/10 Tg = -65 ° C / SIS Kraton411N Oil balance 45 SP = 100 ℃ Calcium carbonate 100 wonderment Mercaptan compounds 5 Dithiol Reactive phenolic resin 5 Methylol content 9-10% ZnO 5 accelerant KPS 0.25 Initiator

Test Example 1: Property evaluation

The physical properties of the pressure-sensitive adhesive compositions prepared in Examples 1 to 16 were evaluated by the following method.

The adhesive is coated on a substrate (OPP, PET, etc.) to a certain thickness (25-50 micrometers on a dry basis) and dried completely. Using the dried one as a sample, heat resistance, adhesion, holding power, initial adhesion, etc. are measured.

Heat resistance

After making the dried sample into a width of 25 mm and a length of 100 mm or more, a length of 100 mm is attached to the SUS304 plate. Then, while maintaining a constant weight at 150 ° C. by connecting the sample to the sample, measure the time when the tape is pushed off the SUS plate.

adhesiveness

The peeling angle was 180 ° (PSTC-1, JIS).

retention

After making the dried sample into a width of 25 mm and a length of 100 mm or more, it is attached to the SUS304 plate in a width of 25 mm and a length of 25 mm. Then, while maintaining a constant weight at 40 ° C. by connecting to the rest of the sample, measure the time when the tape is pushed off the SUS plate.

Initial adhesion

After making the dried sample about 150 mm in length, it is fixed in the longitudinal direction to the bottom of the inclined plate having an inclination of 30 °. The sus ball having a certain weight (7/16 inch) is rolled from the top on a ramp having a 30 ° slope, and the length of the sus ball rolling in contact with the sample at the bottom of the ramp is measured. Measurement temperature 25 ° C.

The results are shown in Tables 17 and 18 below.

division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Heat resistance
(min, 150 ℃) 15 70 20 15 20 70 95 125 adhesiveness
(N / cm, 25 ℃) 9 8 9 9 9 8 8 7 retention
(hr, 40 ℃) 10 15 17 17 10 15 20 25 Initial adhesion
(Cm, 25 ℃) 5 7 5 5 5 7 7 9

division Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 Example 15 Example 16 Heat resistance
(min, 150 ℃) 130 80 100 135 135 115 135 135 adhesiveness
(N / cm, 25 ℃) 6 9 8 5 5 6 5 5 retention
(hr, 40 ℃) 25 15 20 25 25 23 27 27 Initial adhesion
(Cm, 25 ℃) 11 5 8 15 15 13 15 15

As can be seen from the above tables, when used in combination with synthetic rubber rather than natural rubber alone, it had excellent heat resistance and retention under the same conditions. In addition, at the same compounding ratio, as the initiator content increased, the holding power increased and the initial adhesion decreased.

Reactive phenolic resin was added to improve heat resistance and retention. In addition, as the amount of reactive phenol resin was increased, the heat resistance improved, but the initial adhesive strength decreased.

As described above, since various physical properties can be adjusted according to the type of rubber, whether or not a reactive phenol resin is added, and the input amount, it is an important point of the present invention that an adhesive and a tape can be supplied according to the properties desired by the consumer.

Claims (15)

40 parts by weight of natural rubber, 10 parts by weight of synthetic rubber, 45 parts by weight of petroleum resin, 5 parts by weight of reactive phenolic resin, 100 parts by weight of calcium carbonate, 5 parts by weight of mercaptan compound, 5 parts by weight of zinc oxide and 0.25 parts by weight of potassium persulfate Includes,
The synthetic rubber is a SIS rubber having a styrene content of 40% by weight or less,
The mercaptan compound is a heat-resistant rubber-based pressure-sensitive adhesive composition, characterized in that any one selected from the group consisting of 1,3-propanethiol, 1,4-benzenedimethanethiol, 1,16-hexadecanedithiol and mixtures thereof . delete delete delete delete delete delete delete delete delete delete delete A heat-resistant tape produced by applying the heat-resistant rubber-based adhesive composition of claim 1 to at least one surface of a substrate. The heat-resistant tape according to claim 13, wherein the substrate is a cotton cloth. The heat-resistant tape according to claim 13, wherein a heat-resistant rubber-based pressure-sensitive adhesive composition is coated on one surface of the substrate, and a coating layer of an acrylic polymer, a vinyl-based polymer, or an acrylic-vinyl copolymer resin is formed on the other surface.