JP5474913B2 - Transparent adhesive - Google Patents

Description

The present invention relates to a transparent adhesive material , and more particularly to a transparent adhesive material that is transparent and excellent in adhesiveness.

  Conventionally, as this type of transparent composition, a composition mainly composed of a vinyl chloride resin is known.

  For example, a vinyl chloride resin for paste having an average degree of polymerization exceeding 800 and a residual amount of emulsifier of 0.5% by weight or less and a plasticizer having a refractive index of 1.50 to 1.60 as main components. There has been proposed a vinyl chloride resin character eraser with excellent transparency, which is characterized by, for example (see Patent Document 1).

  Moreover, 60-200 weight part of BBP as a plasticizer is added to 100 weight part of paste vinyl chloride resin which contains a phosphoric acid ester type emulsifier, and is produced by emulsion polymerization with a polymerization degree of 2300-2600, and a tin compound, Ba-Zn series A paste vinyl chloride resin composition comprising 0.1 to 5 parts by weight of a stabilizer selected from a compound, a Ca—Zn compound and a mixture thereof has been proposed (see, for example, Patent Document 2).

Japanese Patent Application Laid-Open No. 60-242098 Japanese Examined Patent Publication No. 63-49640

  However, compositions containing these vinyl chloride resins as a main component include a problem of migration.

  On the other hand, in recent years, demands from customers have also diversified in the field of erasing, and there is a demand for transparent erasing rich in decoration, hobby, and playability. However, the conventional kneading contains a sub, so that it is impossible to make the whole dough transparent.

  In addition, since the base resin itself is required to have transparency, there is a problem that the degree of freedom in resin selection is narrow. For example, butadiene rubber, vinyl acetate resin, acrylic resin, olefin-based elastomer, styrene-based elastomer, and the like can be considered as transparent resins, but all have a drawback that they do not have sufficient elongation.

  On the other hand, rubbers such as natural rubber and butyl rubber are excellent in elongation and re-adhesion of the fabric, but are somewhat inferior in transparency and inadequate in shape retention against heat.

The present invention solves the problems of the prior art, and provides a transparent adhesive material that is excellent in transparency and adhesiveness and has sufficient elongation and shape retention with respect to heat.

As a result of diligent research to solve the above problems, the present inventors are excellent in transparency and adhesiveness by adding a specific transparent rubber and a specific amount of softening agent to a specific transparent styrenic elastomer. The present invention was completed by finding that an adhesive material having a shape-retaining property with respect to elongation and heat could be obtained.

That is, claim 1 of the present invention is a styrene-ethylene-propylene copolymer, styrene-ethylene-propylene-styrene copolymer, styrene-ethylene-butadiene-styrene copolymer, styrene-ethylene-ethylene-propylene-styrene. Natural rubber, isoprene rubber, butyl rubber selected from copolymers, transparent styrene elastomer having a tensile elongation at break of 100% or less and a melt flow rate (230 ° C., 2.16 kg) of 1 g / 10 min or less A transparent rubber selected from polybutene and a softening agent are added, and the addition amount of the softening agent is 70 to 130 parts by weight with respect to 100 parts by weight of the transparent styrenic elastomer and the transparent rubber. The content is a transparent adhesive material .

A second aspect of the present invention includes the transparent adhesive material according to the first aspect, wherein the softening agent is a process oil.

The third aspect of the present invention includes the transparent adhesive material according to the first or second aspect, further comprising a filler.

The fourth aspect of the present invention is the transparent adhesive material according to any one of the first to third aspects, wherein the addition amount of the transparent rubber is 5 to 100 parts by weight with respect to 100 parts by weight of the transparent styrene elastomer. Content.

Claim 5 of the present invention is that the addition amount of the filler is 10 parts by weight or less with respect to 100 parts by weight of the transparent styrenic elastomer and the transparent rubber. The material is the content.

According to the present invention, a styrene-based elastomer which is excellent in transparency but lacks in elongation is combined with a specific amount of a softener and a transparent rubber which is slightly inferior in transparency and heat shape retention but excellent in elongation. As a result, a transparent pressure-sensitive adhesive material having good compatibility and both being uniformly dispersed and mixed and having excellent transparency and adhesiveness is provided.

  Furthermore, since the transparent adhesive composition of the present invention is non-drying and excellent in transparency and excellent in adhesiveness, it falls down or drops such as glue, thumbtack, furniture in case of earthquake, OA equipment such as computer, printer, etc. It is possible to provide an adhesive material such as an adhesive mat for preventing the above and an adhesive sheet for dust removal rollers.

As the styrene-ethylene-propylene copolymer, a transparent styrene elastomer used in the present invention (hereinafter referred to as a styrene elastomer) includes Septon 1001 (manufactured by Kuraray Co., Ltd.), Kraton G1701 (manufactured by Kraton Polymer), As styrene-ethylene-propylene-styrene copolymer, Septon 2005, 2006, 2104 ( above, manufactured by Kuraray Co., Ltd.), and as styrene-ethylene-butadiene-styrene copolymer, Septon 8006 ( above. (Kuraray Co., Ltd.), Kraton G1651 (Clayton polymer), and styrene-ethylene-ethylene-propylene-styrene copolymer include Septon 4055 and 4077 (above, Kuraray Co., Ltd.). .

  The styrenic elastomer preferably has a tensile elongation at break of 100% or less. For example, in the above description, Septon 1001, 2104, and Kraton G1701 are <100%, and Septon 2005, 2006, 4055, 4077. 8006 and Kraton G1651 are values that are too small to be measured. In addition, Septon 8004 is 560% and 2002 is 580%.

  Further, the styrene elastomer preferably has a melt flow rate (MFR) (230 ° C., 2.16 kg) of 1 g / 10 min or less, the above-mentioned septon 1001 is 0.1 g / 10 min, and septon 2104 is 0.4 g / min. 10 min, septon 8004 is 0.1 g / 10 min. In addition, Septon 2005, 2006, 4055, 4077, 8006, Clayton G1701 and G1651 have values that are so small that they cannot be measured under the conditions of 230 ° C. and 2.16 kg. The septon 2002 is 70 g / 10 min.

If the tensile elongation at break exceeds 100% or the melt flow rate exceeds 1 g / 10 min, the dough tends to be too firm and, as a result, tends to be difficult to stretch and lack re-adhesiveness. Therefore, Septon 1001, 2005, 2006, 2104, 4055, 4077, 4077, 4077, which have a tensile elongation at break of 100% or less and a melt flow rate (230 ° C., 2.16 kg) of 1 g / 10 min or less. 8006, Kraton G1701, and G1651 are preferable.
The above-mentioned styrenic elastomers are used alone or in combination of two or more as required.
In the present invention, the tensile elongation at break is measured according to JIS K 6301, and the melt flow rate (230 ° C., 2.16 kg) is measured according to JIS K 7210.

  In the present invention, the component imparting elongation to the styrene-based elastomer is preferably a transparent rubber (hereinafter referred to as rubber), and examples of such rubber include natural rubber, isoprene rubber, butyl rubber, polybutene, and the like. Are used alone or in combination of two or more as required. In particular, natural rubber, isoprene rubber, and butyl rubber are preferable. In addition, the rubber | gum in this invention can be used if it is colored even if it has transparency.

  Examples of natural rubber include RSS No. 1, and examples of isoprene rubber include Kraton IR305 (manufactured by Kraton). Examples of the butyl rubber include Exxon Butyl 268, Vistanex MML80, Vistanex MML140 (exxon).

  The amount of rubber to be added varies depending on the type of rubber and the application of the composition of the present invention, and therefore cannot be determined unconditionally. For example, in the case of kneading, it is usually 5 ~ 100 parts by weight are preferred. If the amount is less than 5 parts by weight, the elongation tends to be insufficient.

A softener is usually added to the composition of the present invention. The softening agent, together with rubber, imparts elongation and re-adhesion to a styrene elastomer having a low tensile elongation at break and melt flow rate. As such a softening agent, either mineral oil or vegetable oil can be used, and process oil is particularly suitable. Examples of the process oil include paraffinic oil and naphthenic oil, and the former includes PW32 and the latter includes NP24 (both manufactured by Idemitsu Kosan Co., Ltd.). These may be used alone or in combination as necessary.
The addition amount of the softening agent is usually 70 to 130 parts by weight with respect to 100 parts by weight of the styrene elastomer and rubber. If it is less than 70 parts by weight, it is hard and the elongation is insufficient. On the other hand, if it exceeds 130 parts by weight, it tends to cause sticky bleeding.

  If necessary, a filler that does not impair the transparency can be added to the composition of the present invention. Examples of such additives include LP-3106 [manufactured by Mitsubishi Rayon, acrylic (PMMA) powder], nip seal VN-3 [manufactured by Tosoh, silica (wet method white carbon)] and the like. These are used alone or in combination, if necessary, and the amount used is preferably about 10 parts by weight or less with respect to 100 parts by weight of the styrene elastomer and rubber. If it exceeds 10 parts by weight, it tends to become cloudy. Furthermore, if necessary, an angstrom-level fine oxide, for example, indium oxide, iron oxide, tin oxide, titanium oxide, barium sulfate, etc. can be added for the purpose of imparting conductivity or cutting ultraviolet rays. .

  The transparent adhesive composition of the present invention comprising the above components is kneaded, molded by press molding, injection molding, extrusion molding, or the like, and cut into a predetermined size to obtain a product.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example and a comparative example, these do not restrict | limit the scope of the present invention at all.

  The materials used in the following examples and comparative examples are shown in Table 1. In addition, in description of Table 2-Table 8, unless otherwise indicated, a compounding part number represents a weight part.

Examples 1-4, Comparative Example 1
As shown in Table 2, a resin composition containing “Septon 8006” as the thermoplastic elastomer, butyl rubber “Vistanex MML80” as the rubber, and process oil “PW32” as the softening agent was kneaded and mixed, and then the sample was formed by extrusion molding. Got.
About the obtained sample, transparency, elongation, and shape retention during heating were evaluated by the following methods. The results are shown in Table 2.

"Transparency"
Samples were evaluated with the naked eye and evaluated according to the following criteria.
A: The transparency is very high.
○: High transparency.

"Elongation"
The sample was stretched with both hands, and the degree of elongation was evaluated according to the following criteria.
A: It grows very well.
○: It grows well.
□: Elongates but easily cuts.
Δ: Although it is stretched, a considerable force is required.
X: Not stretched.

"Shape retention"
The sample was stored in a constant temperature bath at 70 ° C. for a certain period, and shape retention was evaluated with the naked eye according to the following criteria.
A: Retain shape until 4 weeks.
○: Retain shape until 3 weeks.
Δ: Retain shape until 2 weeks.

Examples 5-8
As shown in Table 3, physical properties were evaluated in the same manner as in Examples 1 to 4, except that butyl rubber “Vistanex MML140” was used as the rubber. The evaluation results are shown in Table 3. For comparison, the evaluation results of Comparative Example 1 are also shown.

Examples 9-13
As shown in Table 4, physical properties were evaluated in the same manner as in Examples 1 to 4 except that butyl rubber “Exon Butyl 268” was used as the rubber. The evaluation results are shown in Table 4. For comparison, the evaluation results of Comparative Example 1 are also shown.

Examples 14-17
As shown in Table 5, physical properties were evaluated in the same manner as in Examples 1 to 4, except that isoprene rubber “Clayton IR305” and natural rubber “RSS 1” were used as the rubber. The evaluation results are shown in Table 5.

Examples 18 to 25, Reference Examples 1 and 2
As shown in Table 6, Example 2 was used except that Septon 1001, 2005, 2006, 2104, 4055, 4077, 8004, 2002, Kraton G1651, 1701 were used as the thermoplastic elastomer. The same operation was performed to evaluate the physical properties. The evaluation results are shown in Table 6. For comparison, the evaluation results of Example 2 are also shown.
As is apparent from the results in Table 6, Septon 8004 is a styrene elastomer that does not satisfy the conditions that the tensile elongation at break is 100% or less and the melt flow rate (230 ° C., 2.16 kg) is 1 g / 10 min or less. When the same 2002 is used, it is understood that a considerable force is required although it extends.

Examples 28-30, Comparative Examples 2, 3
As shown in Table 7, the physical properties were evaluated in the same manner as in Example 2 except that the amount of process oil “PW32” was changed. Table 7 shows the evaluation results. For comparison, the evaluation results of Example 2 are also shown.
In Example 30, process oil “NP24” was used.

Examples 31-34
As shown in Table 8, physical properties were evaluated in the same manner as in Example 2 except that “LP-3106” and “nip seal VN-3” were added as fillers. The evaluation results are shown in Table 8. For comparison, the evaluation results of Example 2 are also shown.

The samples obtained in the above Examples 1 to 25 and 28 to 34 were transparent and adhesive, and could be used as an adhesive mat for kneading, preventing overturning or dropping, an adhesive sheet for dust removal rollers, and the like. It was.

  As described above, the transparent pressure-sensitive adhesive composition of the present invention has a sufficient elongation and is excellent in re-adhesiveness when repeatedly kneaded, and can provide a transparent kneading rich in cleanliness, clarity and interest. it can.

  Furthermore, since the composition of the present invention is non-drying and excellent in transparency and excellent in adhesiveness, it prevents the fall or fall of OA equipment such as glue, thumbtack, furniture in case of earthquake, computer, printer, etc. Adhesive materials such as an adhesive mat and an adhesive sheet for dust removal rollers can be provided.

Claims (5)

Selected from styrene-ethylene-propylene copolymer, styrene-ethylene-propylene-styrene copolymer, styrene-ethylene-butadiene-styrene copolymer, styrene-ethylene-ethylene-propylene-styrene copolymer, tensile elongation at break A transparent styrene elastomer having a degree of 100% or less and a melt flow rate (230 ° C., 2.16 kg) of 1 g / 10 min or less is softened with a transparent rubber selected from natural rubber, isoprene rubber, butyl rubber, and polybutene agent will be added, a transparent adhesive material amount of the softening agent, characterized in that it is a 70 to 130 parts by weight with respect to the transparent styrene-based elastomer and transparency 100 parts by weight of rubber. The transparent adhesive material according to claim 1, wherein the softening agent comprises process oil. Furthermore, the transparent adhesive material of Claim 1 or 2 formed by adding a filler. The transparent adhesive material according to any one of claims 1 to 3, wherein the addition amount of the transparent rubber is 5 to 100 parts by weight with respect to 100 parts by weight of the transparent styrene-based elastomer. The transparent adhesive material according to any one of claims 1 to 4, wherein an addition amount of the filler is 10 parts by weight or less with respect to 100 parts by weight of the transparent styrenic elastomer and the transparent rubber .