Hot melt composition

Abstract

To provide a hot melt composition that is highly productive because it is suitable for spray coating, is less likely to undergo phase separation during melting, has suppressed surface tack after solidification, and has good weather resistance because it is excellent in moisture and heat resistant creep properties. 【Solution means】 A hot melt composition characterized by containing a styrene-based thermoplastic elastomer (A) having a styrene content of 18% by weight or less, an amorphous polyalphaolefin (B), and a tackifier (C).

Description

Technical Field

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

Background Art

[0002] Conventionally, extensive research and development have been conducted on hot melt compositions. Since hot melt compositions melt when heated and solidify when cooled to room temperature of about 23°C, they are suitably used as adhesives. Their features include being solvent-free, environmentally friendly, capable of solidifying in a short time, and being very easy to handle materials, and since they can improve the working environment at the manufacturing site, they are widely used in various fields.

[0003] In the past, the applicant of the present application invented a hot melt composition containing an amorphous polyalphaolefin (A), a styrenic thermoplastic elastomer (B), and a tackifier (C), wherein the amorphous polyalphaolefin (A) has a melt viscosity (190°C) of 5,000 to 300,000 mPa·s and a tensile strength of 2.3 to 6.0 MPa (Patent Document 1). This hot melt composition exhibited adhesive strength not only to olefin-based materials but also to other materials while maintaining the conventional strength.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] Generally, when building a wooden house, a moisture-permeable waterproof sheet is laid between the exterior material and the interior material. This is provided to block rain leakage from the wall surface and to allow moisture generated by the temperature difference between the inside and outside of the house to escape to the outside.

[0006] In recent years, hot melt compositions have been used in the manufacturing process of moisture-permeable waterproof sheets because of their excellent adhesion stability at room temperature. For moisture-permeable waterproof sheets, a hot melt composition is applied to a non-woven fabric serving as a base material by so-called curtain spraying, a porous film is laminated, and then the sheet is left at room temperature to solidify, wound up, and transported to a construction site for construction. Here, curtain spraying is a very efficient method when applying thinly over a large area, so it can be suitably used in manufacturing moisture-permeable waterproof sheets. Therefore, as the hot melt composition, properties suitable for curtain spraying, such as excellent spray coatability and difficulty in generating phase separation during melting, have been required. Also, it has been required that the surface tack after solidification be suppressed so as not to adhere to the back surface of the moisture-permeable waterproof sheet during winding. Furthermore, since the moisture-permeable waterproof sheet is installed immediately adjacent to the exterior material, good weather resistance, such as in a high-temperature and high-humidity environment, has also been required, and there has been room for improvement.

Summary of the Invention

Problems to be Solved by the Invention

[0007] The problem to be solved by the present invention is to provide a hot melt composition that is suitable for spray coating, has high productivity, is less likely to generate phase separation during melting, has suppressed surface tack after solidification, and has good weather resistance because of excellent wet heat creep resistance.

Means for Solving the Problems

[0008] The present invention is a hot melt composition characterized by containing a styrene-based thermoplastic elastomer (A) having a styrene content of 18% by weight or less, an amorphous polyalphaolefin (B), and a tackifier (C).

Effects of the Invention

[0009] The hot melt composition according to the present invention is suitable for spray coating, so it has high productivity, is less likely to cause phase separation during melting, suppresses surface tack after solidification, and has excellent wet heat creep resistance, so it has the effect of good weather resistance.

Mode for Carrying Out the Invention

[0010] <Styrenic thermoplastic elastomer> In the present invention, a styrenic thermoplastic elastomer (A) having a styrene content of 18% by weight or less is used. The component (A) is used as the base polymer of the hot melt composition according to the present invention.

[0011] A styrenic thermoplastic elastomer is composed of a hard block derived from a styrenic compound and a soft block derived from a diene compound. As the bonding form of each block, there are linear, branched, and radial ones, but linear ones are relatively often provided.

[0012] The types of styrenic thermoplastic elastomers are classified into "unhydrogenated styrenic thermoplastic elastomers" in which the soft block is not hydrogenated and "hydrogenated styrenic thermoplastic elastomers" in which the soft block is hydrogenated.

[0013] Examples of the unhydrogenated styrenic thermoplastic elastomer include styrene-isoprene-styrene block copolymer (SIS) and styrene-butadiene-styrene block copolymer (SBS).

[0014] Examples of the hydrogenated styrenic thermoplastic elastomer include styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene-styrene block copolymer (SEPS), and styrene-ethylene-ethylene / propylene-styrene block copolymer (SEEPS).

[0015] In the present invention, among these, it is preferable to use a hydrogenated styrenic thermoplastic elastomer because of its excellent adhesion stability, and it is particularly preferable to use a styrene-ethylene / butylene-styrene block copolymer (SEBS) or a styrene-ethylene / propylene-styrene block copolymer (SEPS).

[0016] In the styrenic thermoplastic elastomer, various properties of hot melt compositions can be produced by appropriately adjusting the hard block ratio and the soft block ratio. Generally, if the hard block ratio is high, the rigidity increases, and if the hard block ratio is low, the flexibility tends to increase.

[0017] In the present invention, the styrene content ratio of the component (A) needs to be 18% by weight or less, preferably 1 to 17% by weight, more preferably 3 to 16% by weight, and particularly preferably 5 to 15% by weight.

[0018] The inventor of the present invention has found that when the styrene content ratio of the component (A) is within the above range, the sprayability of the hot melt composition according to the present invention is improved. As one of the factors for such an effect, it is presumed that by keeping the styrene content ratio slightly low, it becomes easier to be compatible with other components, and the hot melt composition can be efficiently sprayed during spray coating.

[0019] As the blending ratio of the component (A), it is preferably blended in an amount of 5 to 35 parts by weight, more preferably 8 to 30 parts by weight, and particularly preferably 10 to 25 parts by weight in 100 parts by weight in total of the components (A) to (C).

[0020] Specific examples of the component (A) include GLOBALPRENE 9557D (trade name, manufactured by LCY, styrene-ethylene / butylene-styrene block copolymer (SEBS), bonding form: linear, styrene content ratio: 13% by weight), etc.

[0021] <Amorphous polyalphaolefin> In the present invention, amorphous polyalphaolefin (B) is used. The component (B) is an amorphous olefin polymer.

[0022] As the structure of the component (B), it is preferably included with propylene as a structural unit. Specifically, in addition to a homopolymer of propylene, a copolymer or a terpolymer of propylene and a monomer selected from ethylene, 1-butene, and 1-hexene can be mentioned. Among these, propylene homopolymers and propylene-ethylene copolymers can be preferably used because they have high stability and are easy to handle.

[0023] The inventor of the present invention has found that by using the component (B), the wet heat creep resistance of the hot melt composition according to the present invention is improved. As one of the factors causing such an effect, it is presumed that the cohesive force of the entire system is improved by using the component (B). It is also presumed that the compatibility with the component (A) is good, and a tendency for the wettability to the substrate in spray coating properties to be improved is also observed.

[0024] The melt viscosity (190°C) of the component (B) is preferably 500 to 60,000 mPa·s, more preferably 800 to 30,000 mPa·s, and particularly preferably 1,000 to 10,000 mPa·s.

[0025] The softening point of the component (B) is preferably 90 to 160°C, more preferably 95 to 155°C, further preferably 100 to 150°C, and particularly preferably 105 to 145°C. Being within this range tends to enable both the heat resistance and the spray coating properties of the hot melt composition.

[0026] As the blending ratio of the component (B), it is preferably 5 to 50 parts by weight, more preferably 8 to 45 parts by weight, and particularly preferably 10 to 40 parts by weight in 100 parts by weight in total of the components (A) to (C).

[0027] Specific examples of the component (B) include RT2535 (trade name, manufactured by Rextack, amorphous polyalphaolefin (propylene·ethylene copolymer), melt viscosity (190 °C): 3,500 mPa·s, softening point: 132 °C), Aerafin 17 (trade name, manufactured by Eastman, amorphous polyalphaolefin (propylene-based polymer), melt viscosity (190 °C): 1,500 mPa·s, softening point: 125 °C), RT2385 (trade name, manufactured by Rextack, amorphous polyalphaolefin (propylene·ethylene copolymer), melt viscosity (190 °C): 8,500 mPa·s, softening point: 141 °C), and the like.

[0028] <Adhesion promoter> In the present invention, an adhesion promoter (C) is used. Examples of the type of the component (C) include terpene resins, terpene phenol resins, rosin-based resins, aliphatic hydrocarbon resins, aromatic hydrocarbon resins, alicyclic hydrocarbon resins, and hydrogenated products or modified products thereof.

[0029] The softening point of the component (C) is preferably 60 to 250 °C, more preferably 70 to 200 °C, and particularly preferably 80 to 180 °C.

[0030] As the blending ratio of the component (C), it is preferably 35 to 80 parts by weight, more preferably 40 to 75 parts by weight, and particularly preferably 45 to 70 parts by weight in 100 parts by weight in total of the components (A) to (C).

[0031] Specific examples of the component (C) include YS Resin PX1250 (trade name, manufactured by Yasuhara Chemical Co., terpene resin, softening point: 120°C to 130°C), Tamanol 803L (trade name, manufactured by Arakawa Chemical Industries, terpene phenol resin, softening point: 145 to 160°C), Pink Crystal KR-85 (trade name, manufactured by Arakawa Chemical Industries, rosin-based resin, softening point: 80 to 87°C), YL120 (trade name, manufactured by Yuen Liang Industrial Co., aromatic hydrocarbon resin, softening point: 115 to 125°C), Escorez 5380 (trade name, manufactured by ExxonMobil, alicyclic hydrocarbon resin, softening point: 80 to 90°C), H5-1001 (trade name, manufactured by Henghe Co., aliphatic hydrocarbon resin, softening point: 95 to 105°C), T-REZ HA125 (trade name, manufactured by ENEOS, hydrogenated alicyclic hydrocarbon resin, softening point: 120°C to 130°C), and the like.

[0032] <Crystalline olefin-based elastomer> In addition to the above components (A) to (C), in the present invention, a crystalline olefin-based elastomer (D) can be used. Examples of the component (D) include copolymers of olefin monomers produced using a metallocene catalyst. Specifically, many ethylene-propylene copolymers, ethylene-octene copolymers, etc. are available.

[0033] By using the component (D), the wettability to the substrate in spray coatability is slightly improved, and the surface tackiness after curing can be slightly suppressed, so that the handling tends to be good.

[0034] The blending ratio of the component (D) is preferably 1 to 100 parts by weight, more preferably 2 to 50 parts by weight, and particularly preferably 3 to 30 parts by weight, based on 100 parts by weight of the total of the above components (A) to (C).

[0035] Specific examples of the (D) component include Vistamaxx 8880 (trade name, manufactured by ExxonMobil, crystalline olefin-based elastomer (propylene·ethylene copolymer, ethylene content: 6% by weight), melt viscosity (190°C): 1,200 mPa·s), etc.

[0036] <Other components> In addition, in the present invention, a plasticizer or a wax may be used. By using these components, it is easy to adjust the melt viscosity within an appropriate range, so the workability tends to be further improved.

[0037] Examples of the plasticizer include organic compounds having fluidity at normal temperature (23°C). Examples of the type of plasticizer include paraffinic oil, naphthenic oil, polybutene, polyisobutylene, liquid paraffin, etc. Among these, polybutene and polyisobutylene can be preferably used because they have high stability and are easy to handle.

[0038] Specific examples of the plasticizer include Nisseki Polybutene HV-100 (trade name, manufactured by ENEOS, polybutene, number average molecular weight: 980), PB-950 (trade name, manufactured by Daelim, polybutene, number average molecular weight: 930), etc.

[0039] Waxes include natural waxes and synthetic waxes. Examples of natural waxes include paraffin wax and microcrystalline wax, and examples of synthetic waxes include polyethylene wax and polypropylene wax.

[0040] Specific examples of the wax include Hi-Wax NP500 (trade name, manufactured by Mitsui Chemicals, polypropylene wax, melting point: 161°C), H-503 (trade name, manufactured by Qingdao SinoplasHi-New Material Co, polypropylene wax, melting point: 146°C), Yumex 1010 (trade name, manufactured by Sanyo Chemical Industries, maleic anhydride-modified polypropylene wax, melting point: 135°C), etc.

[0041] In the present invention, an antioxidant may also be used as an additive. Examples of the types of antioxidants include, for example, phosphite-based, naphthylamine-based, p-phenylenediamine-based, quinoline-based, hydroquinone-based, bis / tris polyphenol-based, thiobisphenol-based, hindered phenol-based, etc., and one or more of them can be used in combination.

[0042] Specific examples of the antioxidant include Sumilizer GP (trade name, manufactured by Sumitomo Chemical Co., Ltd.), Songnox 1010 (trade name, manufactured by Songwon Co., Ltd.), Chinox 1010 (trade name, manufactured by Double Bond Chemical Co., Ltd.), etc.

[0043] In the present invention, fillers such as calcium carbonate, talc, and clay, and various additives such as preservatives and colorants may be included.

[0044] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these descriptions.

Examples

[0045] <Examples and Comparative Examples> In the formulation shown in Table 1, kneading was sufficiently performed using a flask adjusted to 180°C to produce hot melt compositions according to Examples and Comparative Examples. Here, the numerical values in Table 1 represent parts by weight. The raw materials used are shown below. GLOBALPRENE 9557D (trade name, manufactured by LCY Co., Ltd., styrene-ethylene / butylene-styrene block copolymer (SEBS), bonding form: linear, styrene content ratio: 13% by weight) GLOBALPRENE 9552U (trade name, manufactured by LCY Co., Ltd., styrene-ethylene / butylene-styrene block copolymer (SEBS), bonding form: linear, styrene content ratio: 30% by weight) RT2535 (trade name, manufactured by Rextack, amorphous polyalphaolefin (propylene-ethylene copolymer), melt viscosity (190 °C): 3,500 mPa·s, softening point: 132 °C) Aerafin 17 (trade name, manufactured by Eastman, amorphous polyalphaolefin (propylene-based polymer), melt viscosity (190 °C): 1,500 mPa·s, softening point: 125 °C) RT2385 (trade name, manufactured by Rextack, amorphous polyalphaolefin (propylene-ethylene copolymer), melt viscosity (190 °C): 8,500 mPa·s, softening point: 141 °C) Escorez 5380 (trade name, manufactured by Exxon, tackifier (alicyclic hydrocarbon resin), softening point: 80 - 90 °C) H5-1001 (trade name, manufactured by Henghe, tackifier (aliphatic hydrocarbon resin), softening point: 95 - 105 °C) Vistamaxx 8880 (trade name, manufactured by ExxonMobil, crystalline olefin-based elastomer (propylene-ethylene copolymer, ethylene content: 6 wt%), melt viscosity (190 °C): 1,200 mPa·s) Affinity GA1900 (trade name, manufactured by Dow, crystalline olefin-based elastomer, melt viscosity (177 °C): 8200 mPa·s) PB-950 (trade name, manufactured by Daelim, polybutene) PB-1300 (trade name, manufactured by Daelim, polybutene) H-503 (trade name, manufactured by Qingdao Sinoplas Hi-New Material Co, polypropylene wax, melting point: 146 °C) Songnox 1010 (trade name, manufactured by Songwon, antioxidant)

[0046]

Table 1

[0047] Regarding the hot melt compositions manufactured in the above examples and the like, various physical property evaluations were conducted in the following manner. The results are shown in Table 2.

[0048] <Spray applicablility> 50 g of the hot-melt composition was put into a hot-melt gun set at 180°C and maintained for 1 hour to be completely melted. Then, spray coating was carried out on a PET film (30 cm × 20 cm) so that the coating amount was 3 g / m 2 and the appearance after coating was visually observed based on the following evaluation criteria. Coating shape: ○ was evaluated when it could be uniformly coated in a fibrous shape during coating, and × was evaluated when the spray was unstable and coating unevenness occurred. Wettability to the substrate: ⊙ was evaluated when it showed very good wettability to the PET substrate immediately after spray coating, ○ was evaluated when it showed good wettability, and × was evaluated when the wettability was poor.

[0049] <Compatibility> 10 g of the hot-melt composition was put into a 30-ml standard bottle, left standing in a thermostat adjusted to 180°C for 24 hours, taken out, and the presence or absence of phase separation was visually confirmed. ○ was evaluated for those that were uniform without phase separation, and × was evaluated for those with phase separation.

[0050] <Moisture and heat resistance creep property> Using a hot-melt gun set at 180°C, the hot-melt composition was bead-coated on a B-flute corrugated board (10 cm × 2.5 cm) at a coating amount of 3 g / m 2 to prepare a test piece by placing the corrugated board on top and crimping it with a 1-kg load for 2 seconds. The test piece was cured at 23°C for 24 hours, left standing in a thermostat adjusted to a temperature of 60°C and a humidity of 90% for 30 minutes, then a 300-g weight was attached to one side, and the time until the weight fell was measured. Those with a time until falling of 100 minutes or more were evaluated as ○, and those with a time less than 100 minutes were evaluated as ×.

[0051] <Surface tackiness> 20 g of the hot melt composition was placed in a metal can, allowed to stand in a thermostat adjusted to 180°C until completely melted, then taken out and poured onto a smooth release paper, and cured at 23°C for 24 hours. Thereafter, the surface of the solidified hot melt was strongly pressed with a finger, and the feeling when released was confirmed by sensory evaluation. When there was no residue on the finger and almost no stickiness, it was evaluated as ◎; when there was a slight feeling of sticking to the finger, it was evaluated as 〇; when the stickiness was strong, it was evaluated as ×.

[0052]

Table 2

[0053] When the hot melt composition according to the examples was produced using various styrene-based thermoplastic elastomers, it was found to be suitable for spray coating, resulting in high productivity, less phase separation during melting, suppressed surface tack after curing, and excellent moisture and heat resistant creep properties, indicating good weather resistance.

[0054] In particular, when comparing Example 1 and Comparative Example 1, superiority or inferiority in spray coatability and moisture and heat resistant creep properties was observed depending on the presence or absence of the amorphous polyalphaolefin (B) formulation. Also, when comparing Example 4 and Comparative Example 2, superiority or inferiority in spray coatability and compatibility was observed by changing the styrene content ratio of the styrene-based thermoplastic elastomer.

Claims

1. A hot melt composition for residential use, characterized in that, out of a total of 100 parts by weight of components (A) to (C), it contains 5 to 35 parts by weight of a styrene-based thermoplastic elastomer (A) having a styrene content of 18% by weight or less, 5 to 50 parts by weight of an amorphous polyalphaolefin (B), 35 to 80 parts by weight of a tackifier (C), and a wax.

2. A hot melt composition for a moisture-permeable waterproof sheet, comprising, per 100 parts by weight of the total of the components (A) to (C), 5 to 35 parts by weight of a styrene-based thermoplastic elastomer (A) having a styrene content of 18% by weight or less, 5 to 50 parts by weight of an amorphous polyalphaolefin (B), and 35 to 80 parts by weight of a tackifier (C).

3. A moisture-permeable waterproof sheet coated with the hot-melt composition for moisture-permeable waterproof sheets according to claim 2.

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