Hot-melt composition

Abstract

To provide a hot-melt composition having good application workability due to its moderate melt viscosity, excellent mechanical properties after solidification and maintaining certain durability even in a low-temperature environment.SOLUTION: There is provided a hot-melt composition comprising an olefinic elastomer (A) and a tackifier (B), wherein the olefinic elastomer (A) has melt viscosity (190°C) of 100 to 30000 mPa s and the hot-melt composition comprises an olefinic elastomer (a1) having needle penetration (ASTM D-1321) of 30 dmm or more and an olefinic elastomer (a2) having the needle penetration of 25 dmm or less as the olefinic elastomer (A).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a hot melt composition. [Background technology]

[0002] Hot melt compositions have been widely researched and developed. Hot melt compositions melt when heated and solidify when cooled to room temperature of about 23°C, and are therefore suitable for use as adhesives. Their characteristics include being solvent-free, environmentally friendly, curing in a short time, and being a very easy-to-handle material, and because they can improve the working environment at manufacturing sites, they are widely used in a variety of fields.

[0003] In the past, the applicant of the present application invented a hot melt composition comprising an olefin elastomer (A), a tackifier (B), and a wax (C), the olefin elastomer (A) comprising an olefin elastomer (a1) having a melt flow rate (ASTM D-1238, 230°C / 2.16kg) of 1 to 500g / 10min and an olefin elastomer (a2) having a melt viscosity (190°C) of 100 to 30,000mPa·s (Patent Document 1). This hot melt composition exhibits adhesive strength to fibrous materials, has good workability due to its long open time and moderate melt viscosity, and is also excellent in impact resistance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-164652 A

[0005] Conventionally, in various fields, filters made of fibrous materials have been provided inside products for the purposes of exhausting heat, filtering, and preventing the intrusion of foreign matter, and hot melt compositions are preferably used to process and fix the shape of the filter in accordance with the internal structure of each product.

[0006] For example, when a hot melt composition is used for a filter installed in a transport device or an electrical appliance, a certain level of melt viscosity is required to improve the ease of application, and improvement of mechanical properties after solidification is required. In addition, it is required to maintain a certain level of durability in a severe low-temperature environment in winter. Here, in the hot melt composition according to Patent Document 1, it is somewhat difficult to achieve both improvement of mechanical properties and durability in a low-temperature environment, and there is room for improvement. Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the present invention is to provide a hot melt composition which has a suitable melt viscosity and hence good coating workability, has excellent mechanical properties after solidification, and can maintain a certain degree of durability even in a low-temperature environment. [Means for solving the problem]

[0008] The hot melt composition comprises an olefin-based elastomer (A) and a tackifier (B), the olefin-based elastomer (A) having a melt viscosity (190°C) of 100 to 30,000 mPa s, and the olefin-based elastomer (A) comprises an olefin-based elastomer (a1) having a penetration (ASTM D-1321) of 30 dmm or more and an olefin-based elastomer (a2) having a penetration of 25 dmm or less. Effect of the Invention

[0009] The hot melt composition of the present invention has an appropriate melt viscosity, and therefore has good coating workability, excellent mechanical properties after solidification, and is effective in maintaining a certain degree of durability even in a low-temperature environment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] <Olefin elastomer> In the present invention, an olefin-based elastomer (A) is used as a base polymer for the hot melt composition of the present invention.

[0011] The component (A) preferably contains propylene as a structural unit. The type of the component (A) may be a propylene homopolymer, a copolymer or terpolymer of propylene and a monomer selected from ethylene, 1-butene, and 1-hexene, etc. Among these, a propylene-ethylene copolymer or a propylene-1-butene copolymer is preferably used because of its high stability and ease of handling.

[0012] The melt viscosity of component (A) (190°C, ASTM D-3236) must be 100 to 30,000 mPa·s, preferably 1,000 to 25,000 mPa·s, more preferably 2,000 to 20,000 mPa·s, and particularly preferably 3,000 to 15,000 mPa·s. By having the melt viscosity within this range, the melt viscosity of the hot melt composition can be kept within an appropriate range, and stability during storage at room temperature and when melted at high temperatures tends to be improved.

[0013] Furthermore, the component (A) must contain an olefin-based elastomer (a1) having a penetration (ASTM D-1321) of 30 dmm or more, and an olefin-based elastomer (a2) having a penetration (ASTM D-1321) of 25 dmm or less.

[0014] The penetration (ASTM D-1321) of the (a1) component must be 30 dmm or more, preferably 33 dmm or more, more preferably 35 dmm or more, even more preferably 38 dmm or more, and particularly preferably 40 dmm or more.

[0015] Specific examples of the (a1) component include amorphous polyalphaolefins such as RT2585 (trade name, manufactured by Rextack Corporation, propylene-ethylene copolymer, melt viscosity (190°C, ASTM D-3236): 8,500 mPa s), penetration (ASTM D-1321): 45 dmm).

[0016] Furthermore, the penetration (ASTM D-1321) of the (a2) component must be 25 dmm or less, preferably 22 dmm or less, more preferably 20 dmm or less, even more preferably 18 dmm or less, and particularly preferably 15 dmm or less.

[0017] Specific examples of the (a2) component include amorphous polyalphaolefins such as RT2788 (product name, manufactured by Rextac Corporation, propylene-1-butene copolymer, melt viscosity (190°C, ASTM D-3236): 8,500 mPa s), penetration (ASTM D-1321): less than 10 dmm).

[0018] Here, when only the (a1) component is used, the mechanical properties tend to be poor due to lack of strength and elongation after solidification, and when only the (a2) component is used, the flexibility at -20°C is low, so the low-temperature durability tends to be poor.

[0019] The inventors of the present invention have found that the use of both components (a1) and (a2) results in excellent mechanical properties due to high strength and elongation after solidification, and excellent low-temperature durability due to high flexibility at -20°C, and have completed the present invention. One of the factors that produces such effects is believed to be that the inclusion of two types of olefin-based elastomers with different penetrations improves the entanglement of polymer chains, thereby increasing the interaction between the molecules.

[0020] The mixing ratio (weight ratio) of the (a1) and (a2) components is preferably 1:0.1-20, more preferably 1:0.5-15, further preferably 1:1-12, and particularly preferably 1:3-10.

[0021] <Tackifier> In the present invention, a tackifier (B) is used. Examples of the type of component (B) include terpene resins, terpene phenol resins, rosin resins, aliphatic hydrocarbon resins, aromatic hydrocarbon resins, alicyclic hydrocarbon resins, and hydrogenated or modified products thereof.

[0022] The softening point of the component (B) is preferably from 60 to 250°C, more preferably from 70 to 200°C, and particularly preferably from 80 to 180°C.

[0023] The blending ratio of the (B) component is preferably 1 to 1000 parts by weight, more preferably 2 to 500 parts by weight, and particularly preferably 3 to 100 parts by weight, per 100 parts by weight of the (A) component.

[0024] Specific examples of the component (B) include YS Resin PX1250 (trade name, manufactured by Yasuhara Chemical Co., Ltd., terpene resin, softening point: 120°C to 130°C), Tamanor 803L (trade name, manufactured by Arakawa Chemical Industries, Ltd., terpene phenol resin, softening point: 145°C to 160°C), Pine Crystal KR-85 (trade name, manufactured by Arakawa Chemical Industries, Ltd., rosin resin, softening point: 80°C to 87°C), HM-1000 (trade name, manufactured by Henghe Co., Ltd., aromatic hydrocarbon resin, softening point: 100°C), and T-REZ HA125 (trade name, manufactured by ENEOS Corporation, hydrogenated alicyclic hydrocarbon resin, softening point: 120°C to 130°C).

[0025] <Other ingredients> In addition, a plasticizer (X) can be used within the range that does not impair the effects of the present invention. The use of the component (X) not only imparts plasticity, but also improves the dispersibility of the components (A) and (B), thereby increasing the wettability of the adherend surface and improving the adhesion between the layers.

[0026] The component (X) can be, for example, an organic compound that is solid at room temperature (23° C.). Specific examples include wax, which can be classified into natural wax and synthetic wax. Natural waxes include paraffin wax and microcrystalline wax, and synthetic waxes include polyethylene wax and polypropylene wax. Among these, synthetic waxes are preferably used because they are highly stable and easy to handle.

[0027] The blending ratio of the (X) component is preferably 1 to 300 parts by weight, more preferably 2 to 200 parts by weight, and particularly preferably 3 to 100 parts by weight, per 100 parts by weight of the (A) component.

[0028] Specific examples of the (X) component include Hiwax 800P (trade name, manufactured by Mitsui Chemicals, Inc., polyethylene wax), PE H-110 (trade name, manufactured by SQI Thailand, softening point: 110°C, polyethylene wax), and H-506 (trade name, manufactured by Qingdao Sinoplas, polypropylene wax).

[0029] In the present invention, an antioxidant can be used as an additive. Examples of the type of the component include phosphites, naphthylamines, p-phenylenediamines, quinolines, hydroquinones, bis-tris-polyphenols, thiobisphenols, and hindered phenols, and one or more of them can be used in combination. Specific examples of the component include Sumilizer GP (trade name, manufactured by Sumitomo Chemical Co., Ltd.) and Songnox 1010 (trade name, manufactured by Songwon Co., Ltd.).

[0030] In addition, in the present invention, various additives such as fillers such as calcium carbonate, talc, and clay, preservatives, and colorants may be contained.

[0031] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these descriptions. EXAMPLES

[0032] <Examples and Comparative Examples> The hot melt compositions of the Examples and Comparative Examples were produced by thoroughly kneading the ingredients in the formulation shown in Table 1 in a flask adjusted to 180° C. Here, the numerical values ​​in Table 1 represent parts by weight. The raw materials used are shown below. RT2585 (product name, manufactured by Rextack, propylene-ethylene copolymer, melt viscosity (190°C, ASTM D-3236): 8,500 mPa·s), penetration (ASTM D-1321): 45 dmm) RT2788 (trade name, manufactured by Rextack, propylene-1-butene copolymer, melt viscosity (190°C, ASTM D-3236): 8,500 mPa·s), penetration (ASTM D-1321): less than 10 dmm) HM-1000 (Product name, manufactured by Henghe, aromatic hydrocarbon resin, softening point: 100℃) H-506 (product name, polypropylene wax, manufactured by QINGDAO SINOPLAS) Songnox 1010 (product name, manufactured by Songwon, antioxidant)

[0033] [Table 1]

[0034] The hot melt compositions produced in the above examples were evaluated for various physical properties in the following manner. The results are shown in Table 2.

[0035] <Melt viscosity> Using a Brookfield viscometer, 10 g of the hot melt composition was melted at 180°C and allowed to stand for 10 minutes, after which rotation was started with a spindle No. 27 at a rotation speed of 5 rpm, and the melt viscosity (mPa·s) after 10 minutes was measured.

[0036] <Softening point> The softening point (° C.) of each hot melt composition was measured in accordance with JIS K 6863.

[0037] <Tensile strength / tensile elongation> The hot melt composition was melted at 180°C and formed into a sheet having a thickness of 2 mm, and then a test piece having a dumbbell No. 3 shape according to JIS K 6251 was prepared. The test piece was then aged at 23°C for 24 hours, and the tensile strength (N / mm 2 ) and tensile elongation (mm) were measured. Tensile strength is 1.5N / mm 2 The above are marked with ◎ and 1.5N / mm 2 Less than 1.0N / mm 2 The above are marked as ◯ and 1.0N / mm 2 Less than 0.5N / mm 2 The above are classified as △ and 0.5N / mm 2 In addition, tensile elongation of 80 mm or more was evaluated as ⊚, tensile elongation of less than 80 mm and 60 mm or more was evaluated as ◯, tensile elongation of less than 60 mm and 40 mm or more was evaluated as △, and tensile elongation of less than 40 mm was evaluated as x.

[0038] <-20℃ flexibility> The hot melt composition was melted at 180°C to form a sheet with a thickness of 2 mm, which was then cut to a size of 10 cm x 1 cm to prepare a test piece. The test piece was then cured at -20°C for 24 hours, after which the center portion was bent at a right angle, and the result was visually observed. The test pieces were rated as ⊚ when no cracks were observed in any part of the test piece, Δ when a crack was observed in any part of the test piece, and x when the test piece was broken. 25mm).

[0039] [Table 2]

[0040] When the hot melt compositions according to the Examples and Comparative Examples were produced, the melt viscosity and softening point at 180°C were comparable, but the Examples had higher strength and elongation after solidification than the Comparative Examples, and thus were superior in mechanical properties. Also, the compositions had higher flexibility at -20°C, and thus were superior in low-temperature durability.

Claims

1. Contains an olefin-based elastomer (A) and a tackifier (B), The melt viscosity (190°C) of the olefin-based elastomer (A) is 100 to 30,000 mPa·s, A hot melt composition comprising, as the olefin-based elastomer (A), an olefin-based elastomer (a1) having a needle penetration (ASTM D-1321) of 30 dmm or more, and an olefin-based elastomer (a2) having a needle penetration (ASTM D-1321) of 25 dmm or less.

2. 2. The hot melt composition according to claim 1, wherein the olefinic elastomer (A) is an amorphous polyalphaolefin.

3. 3. The hot melt composition according to claim 1, which is used for a filter.

4. 3. An article manufactured using the hot melt composition according to claim 1 or 2.

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