JP2000226561A - Hot-melt adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot-melt adhesive with well-balanced characteristics, being better than the conventional hot-melt adhesive at least in one of the properties of higher flexibility, applicability at a lower temperature, lower viscosity during the application step, higher temperature at which the tack is formed, higher resistance to blocking, and shorter open time. SOLUTION: This hot-melt adhesive contains (A) 50 to 90 wt.% of an amorphous olefinic polymer, (B) 5 to 44 wt.% of a crystalline ethylenic polymer, obtained by polymerizing a monomer containing at least 65 wt.% of crystalline polypropylene wax having a softening temperature of 120 deg.C or higher and/or ethylene, and (C) 1 to 20 wt.% of a tackiness imparting resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hot-melt adhesive, and more particularly to a hot-melt adhesive used for a filter made by pleating a filter medium.

[0002]

2. Description of the Related Art It is known to remove dust by passing air or other fluid through a filter made by pleating (folding) a filter material such as a nonwoven fabric. The folds of the filter media are made in order to make the area of the filter for the fluid passing therethrough as large as possible. For this purpose, it is preferable that the folds are higher and the number thereof is larger. However, when the height of the pleats and the number of the pleats are increased, the pleats are deformed due to the pressure of the passing fluid, and the pleats are more likely to come into contact with each other. The fold contact reduces the filtration area of the filter, reduces the air permeability, and causes a large pressure loss, which causes a decrease in filter performance. Therefore, it is necessary to prevent fold contact.

[0003] Various methods have been proposed to prevent pleat contact. For example, a hot-melt adhesive that has been applied linearly in a direction across the fold line to the filter medium before the fold is continuously folded, and then the hot-melt adhesive that has been fold-folded and solidified between the folds and folds of the filter. A method of preventing the deformation of the fold by interposing the fold is disclosed (see Japanese Patent Application Laid-Open No. 4-40206). Also, for example,
A method is disclosed in which a tensile member is bonded to one surface of a zigzag-shaped pleated filter medium with a hot melt adhesive at a top portion to prevent deformation of folds and obtain a filter having high mechanical tensile strength ( JP-A-1-317
No. 519). Furthermore, foamable resin is used as a hot melt adhesive, for example, in order to make the arrangement of the pleats orderly and to obtain a filter that is hard to lose its shape, to have flexibility in the adhesiveness between the pleats and the pleats of the filter. (See Japanese Patent Application Laid-Open No. 7-47211).

As described above, the hot melt adhesive plays an extremely important role in a method for preventing the pleats from coming into contact with the pleated filter. However, the hot melt adhesive which has been conventionally used for pleating a filter medium has been used. Since the adhesives were ethylene / vinyl acetate (EVA) adhesives and polyethylene, polypropylene, and polyethylene / polypropylene adhesives (see JP-A-5-103936), the following problems were encountered. Was.

When the filter after pleating and bonding with a hot melt adhesive is fitted into a smaller mold, or when the filter is subjected to various secondary moldings such as cylindrical or zigzag, hot melt bonding is required. Since the flexibility of the agent is low, the adhesive surface of the hot melt adhesive is easy to peel off,
It was difficult to perform processing as specified. If the flexibility is increased, the mold is easily broken at a high temperature. Therefore, if a hot melt adhesive having a high softening point is used to prevent the mold from being broken at a high temperature, there is a problem that the viscosity increases and the coating temperature increases.

In the case of polyethylene, polypropylene, and polyethylene / polypropylene hot melt adhesives, the viscosity and the temperature dependence of the viscosity of the hot melt adhesive are high, and unless the temperature is high, a low viscosity that can be applied in an industrial production process. Therefore, for example, a hot melt adhesive had to be applied at a high temperature of 180 ° C. or more. Therefore, for example, when the filter medium of the filter is polypropylene, the polypropylene as the filter medium is deformed by the application temperature of 180 ° C. If the coating temperature is lowered in order to avoid deformation of the polypropylene of the filter medium, the viscosity of the hot melt adhesive becomes too high, making it impossible to apply the hot melt adhesive stably. For example,
When applying at 150 ° C., the viscosity of the hot melt adhesive is preferably 30,000 cps or less.

In recent years, from the viewpoint of protecting the global environment, pleated filters have been tending to be sold in polyethylene bags or the like as replacement parts without replacing the filters with molds. Due to the low temperature at which tack (stickiness) of the melt adhesive occurs, the hot melt adhesive becomes tacky during transportation as the temperature inside the container rises, and the packaging bag adheres to the pleated filter. There was also the problem of doing so.

Further, in the case of amorphous polyethylene, polypropylene, and polyethylene / polypropylene hot melt adhesives, the rate of solidification of the adhesive is slow. It is necessary to lengthen the time until the pleated molding (hereinafter referred to as "open time") in accordance with the time during which the adhesive solidifies. In order to make the time to fold the filter longer, the speed of the line that makes the filter is reduced, or the distance from the point where the adhesive is applied to the filter to the point where the filter is folded is increased. I have. Therefore, there is also a problem that productivity is very poor because the open time is long. Therefore, hot melt adhesives with good balance of properties such as high flexibility, low coating temperature, low viscosity during coating, high temperature at which tack occurs, high blocking resistance, and short open time. Is required.

[0009]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its objects are to provide high flexibility, low coating temperature, low viscosity during coating, and tackiness. To provide a hot-melt adhesive having at least one of the above-mentioned properties that is improved compared to conventional hot-melt adhesives, such as high temperature, high blocking resistance, and short open time. It is.

[0010]

According to one aspect of the present invention, there is provided a novel adhesive comprising (A) a polymer of amorphous olefin: 50-90% by weight, and (B) a softening point. Is 12
A crystalline ethylene polymer obtained by polymerizing a monomer having a content of crystalline polypropylene of 0 ° C. or more and / or (C) ethylene of 65% by weight or more: 5 to 44% by weight, and (D) a tackifying resin: a hot melt adhesive comprising 1 to 20% by weight, which comprises, in particular,
It is suitable for a hot melt adhesive for producing a filter by using for pleating.

In the present invention, "(A) an amorphous olefin polymer" refers to a known olefin polymer having 2 to 4 carbon atoms, and any known olefin polymer may be used. Can be. (A) The amorphous olefin polymer includes a homopolymer, a copolymer or a mixture of olefins having 2 to 4 carbon atoms. Examples of such an amorphous olefin polymer (A) include a propylene polymer,
Examples thereof include a copolymer of ethylene and propylene, a copolymer of propylene and 1-butene, a copolymer of ethylene and 1-butene, and a copolymer of propylene and ethylene and 1-butene. Particularly, a copolymer of amorphous propylene and 1-butene, a copolymer of amorphous ethylene and 1-butene, a copolymer of amorphous propylene and a copolymer of ethylene and 1-butene, and Any mixture of butene copolymers is preferred.

Here, the number average molecular weight of the (A) amorphous olefin polymer is not particularly limited as long as the intended performance of the present invention is exhibited, but is generally from 2,000 to 3,000.
0 is preferable, 4000 to 25000 is more preferable,
6000 to 25000 are particularly preferred. In addition, 19
The viscosity at 0 ° C. is preferably from 1500 to 50,000 cps, more preferably from 1500 to 30,000 cps. Furthermore, the glass transition temperature (hereinafter, “glass transition temperature” in the present specification refers to the glass transition start temperature and the glass transition end temperature measured by DSC using a method similar to the method described in DIN 53765. The arithmetic mean temperature is preferably −20 to −40 ° C. The elongation at break is preferably 100% or more, more preferably 200% or more. The adhesive of the present invention preferably contains 50 to 90% by weight, more preferably 55 to 85% by weight, and more preferably 60 to 7% by weight of the amorphous olefin polymer (A).
It is particularly preferred to contain 5% by weight. In the adhesive of the present invention, (A) an amorphous olefin polymer can be used alone or in combination.

In one embodiment of the adhesive of the present invention,
"(A) Amorphous olefin polymer" is an amorphous 1
-Butene copolymers are preferred. Here, the “amorphous 1-butene copolymer” has a function of imparting flexibility to the hot melt adhesive and reducing the viscosity, and is a known 1-butene copolymer. And any amorphous one can be used. In particular, a copolymer of propylene and 1-butene, a copolymer of ethylene and 1-butene, and a copolymer of propylene and ethylene and 1-butene can be used. At least one selected from polymers is preferred.

As such an amorphous 1-butene copolymer, for example, Ubetack (UB) from Ube Industries, Ltd.
ETAC), Huls (Vestoplast), Shell Japan (Shell Chem.), Polybutylene, and Mitsui Chemicals (Polybutene). It is marketed by name.

Here, the number average molecular weight of the amorphous 1-butene copolymer is not particularly limited as long as the intended performance of the present invention is exhibited, but generally it is preferably 4000 to 25000, and 6000 to 2000. 15000 is more preferred. The viscosity at 190 ° C. is 1500 to 50,000 cp.
s is preferred, and 1500-30000 cps is more preferred. Further, its glass transition temperature is from -20 ° C to -4 ° C.
It is preferably 0 ° C., and the elongation at break is preferably 100% or more, more preferably 200% or more.

The amorphous 1-butene copolymer is as follows:
Compatible with the amorphous 1-butene copolymer,
At least one of the other amorphous olefin polymers that provides improved properties or notable effects to the butene copolymer.
Species can be included. As such "another amorphous olefin polymer", at least one selected from amorphous polypropylene and amorphous ethylene / propylene copolymer is preferable.

The properties of these "other amorphous olefin polymers" are not particularly limited as long as the desired performance of the present invention is exhibited, but their glass transition temperatures are from -10.degree.
-40 ° C is preferred. Here, the viscosity of the amorphous polypropylene at 190 ° C. is preferably 400 to 8500 cps, more preferably 1500 to 8500 cps, and the viscosity of the amorphous ethylene and propylene copolymer at 190 ° C. is 400 to 8500 cps. Preferably 1500 to 8
500 cps is more preferred.

Therefore, in the adhesive of the present invention,
(A) An amorphous olefin polymer is composed of propylene and 1
-Butene copolymer, ethylene and 1-butene copolymer and propylene, at least one amorphous 1-butene copolymer selected from ethylene and 1-butene copolymer, It is preferably an amorphous 1-butene copolymer which may contain at least one selected from amorphous polypropylene and amorphous ethylene / propylene copolymer.

In the present invention, "(B) the softening point is 120 ° C.
The above crystalline polypropylene wax and / or (C)
"Crystalline ethylene polymer obtained by polymerizing a monomer having an ethylene content of 65% by weight or more" means that the polymer retains its shape at a high temperature (that is, the hot melt adhesive does not drip at a high temperature).
And / or shorten the open time (improve productivity). In the adhesive of the present invention, (B) a crystalline polypropylene wax having a softening point of 120 ° C. or more and / or (C) a crystalline obtained by polymerizing a monomer having an ethylene content of 65% by weight or more. Ethylene polymer,
It is preferably contained in an amount of 5 to 44% by weight, more preferably 5 to 30% by weight, and particularly preferably 5 to 20% by weight.

Here, "(B) a crystalline polypropylene wax having a softening point of 120 ° C. or higher" refers to a waxy crystalline polypropylene having a softening point of 120 ° C. or higher. Any polypropylene wax can be used, and commercially available ones can be used. (B) The number average molecular weight of the crystalline polypropylene wax having a softening point of 120 ° C. or higher is not particularly limited as long as the desired performance of the present invention is exhibited, but is generally 2,000.
It is preferably from 20,000 to 20,000, more preferably from 2,000 to 10,000, and particularly preferably from 2,000 to 7000. The softening point is preferably from 120 to 160 ° C, more preferably from 140 to 160 ° C. The penetration is preferably 2 or less, particularly preferably 1 or less. In the adhesive of the present invention, (B)
A crystalline polypropylene wax having a softening point of 120 ° C. or more can be used alone or in combination.

Here, “(C) ethylene content is 65%
The crystalline ethylene polymer obtained by polymerizing the monomer in an amount of not less than 65% by weight "may include a monomer copolymerizable with ethylene, and a monomer containing not less than 65% by weight of ethylene. And any known ethylene polymer that is crystalline, and commercially available ones can be used. Examples of such “(C) a crystalline ethylene polymer obtained by polymerizing a monomer having an ethylene content of 65% by weight or more” include, for example, a monomer having an ethylene content of 100% by weight. Crystalline polyethylene obtained by polymerizing the polymer, the ethylene content is 65% by weight
The ethylene-vinyl acetate copolymer in which the balance is vinyl acetate, the ethylene content is 65% by weight or more, and the balance is n
An ethylene-n-butyl acrylate copolymer which is -butyl acrylate, an ethylene-ethyl acrylate copolymer having an ethylene content of 65% by weight or more and the balance being ethyl acrylate, and an ethylene content of 65% by weight or more. Ethylene- with the remainder being methyl acrylate
Examples thereof include a methyl acrylate copolymer. Particularly, crystalline polyethylene obtained by polymerizing a monomer having an ethylene content of 100% by weight, and an ethylene-vinyl acetate copolymer having an ethylene content of 65% by weight or more and a balance of vinyl acetate are used. preferable

The properties of the crystalline ethylene polymer obtained by polymerizing the monomer (C) having an ethylene content of 65% by weight or more are not particularly limited as long as the intended performance of the present invention is exhibited. The specific gravity (23 ° C.) is 0.90
1.00 is preferable, 0.91 to 1.00 is more preferable, and 0.94 to 1.00 is particularly preferable. (C) In a crystalline ethylene polymer obtained by polymerizing a monomer having an ethylene content of 65% by weight or more, the ethylene content is preferably 65% by weight or more, and more preferably 70% by weight or more. It is preferably at least 80% by weight. In the adhesive of the present invention, the content of (C) ethylene is 65%.
Crystalline ethylene polymers obtained by polymerizing at least% by weight of monomers can be used alone or in combination.

In the present invention, "(D) tackifying resin"
Is a tackifying resin commonly used in hot melt adhesives, a resin having a relatively low molecular weight, which improves the wettability of the adhesive, imparts initial adhesive strength, and melt viscosity of the adhesive. To improve the workability of the coating process.

As the “(D) tackifying resin”, for example,
At least one selected from aromatic petroleum resins, aliphatic petroleum resins, aliphatic-aromatic petroleum resins, terpene resins, rosin resins, modified terpene resins, modified rosin resins, styrene petroleum resins, and the like In particular, a polymer of dicyclopentadiene and / or a copolymer of dicyclopentadiene and a styrene derivative (including styrene) is preferable. These can be used alone or in combination as appropriate. In the hot melt adhesive of the present invention, the above-mentioned (D) tackifier resin is preferably contained in an amount of 1 to 20% by weight,
More preferably, it contains.

Further, in the present invention, the term "hydrogenated tackifying resin (hereinafter referred to as" hydrogenated tackifying resin ")" refers to the above (D) tackifying resin partially or completely hydrogenated. An added tackifying resin, which is colorless or nearly white, reduces odor by reducing the number of carbon-carbon double bonds in the molecular chain, and does not substantially sense odor. , Which means reduced oxidative deterioration during melting or long-term use. Examples of the “hydrogenated tackifying resin” include, for example, partially or completely hydrogenated aromatic petroleum resins, aliphatic petroleum resins, aliphatic-aromatic petroleum resins, terpene resins, rosin Resins, modified terpene resins, modified rosin resins, styrene petroleum resins, and the like. In particular, a partially or completely hydrogenated dicyclopentadiene polymer and / or dicyclopentadiene and styrene Copolymers of derivatives (including styrene) are preferred.

In the hot melt adhesive of the present invention,
Further, it may contain "(E) a wax having a softening point of 70C or more and less than 120C". Here, “(E) a wax having a softening point of 70 ° C. or more and less than 120 ° C.” has a function of improving the blocking resistance of a hot melt adhesive at a high temperature. At least one selected from a synthetic wax, a crystalline polyolefin wax, a microcrystalline wax, or the like, which is produced by a Fischer-Tropsch method, a polymerization method, or a decomposition method at a temperature lower than 0 ° C can be exemplified. In particular, a synthetic wax, a polyethylene wax, a low molecular weight crystalline polyethylene wax, a microcrystalline wax, or the like having a softening point of 80 to 110 ° C and manufactured by the Fischer-Tropsch method is preferable.

(E) The wax having a softening point of 70 ° C. or more and less than 120 ° C. preferably has a softening point of 70 ° C. or more and less than 120 ° C., and more preferably 80 ° C. or more and 110 ° C. or less. The wax (E) having a softening point of 70 ° C. or more and less than 120 ° C.
They can be used alone or in combination. In the hot melt adhesive of the present invention, (E) the softening point is 7
The wax having a temperature of 0 ° C or more and less than 120 ° C is preferably contained in an amount of 1 to 15% by weight, more preferably 3 to 15% by weight.

In one preferred embodiment of the adhesive of the present invention, (C) the crystalline ethylene polymer is a crystalline polyethylene wax, and (B) the softening point is 120 ° C.
The above crystalline polypropylene wax and / or (C)
A hot melt adhesive comprising 5 to 30% by weight of a crystalline polyethylene wax. Here, the adhesive of the present embodiment preferably contains 5 to 30% by weight of (B) crystalline polypropylene wax having a softening point of 120 ° C. or more and / or (C) crystalline polyethylene wax.
More preferably, it is contained by weight.

In the adhesive of this embodiment, the “(C) crystalline ethylene polymer” includes a monomer having an ethylene content of substantially 100% by weight (other monomer usually contained as an impurity). Crystalline polyethylene wax which is a polymer of crystalline ethylene obtained by polymerizing ethylene (which may contain a substance) is preferred. Here, "crystalline polyethylene wax" refers to waxy crystalline polyethylene having a softening point of 120 ° C. or more and a penetration of 2 or less, and any known crystalline polyethylene wax may be used. And commercially available ones can be used.

The number average molecular weight of the “crystalline polyethylene wax” is not particularly limited as long as the desired performance of the present embodiment is exhibited, but is generally preferably from 1,000 to 10,000, more preferably from 1,000 to 4,000, and more preferably from 100 to 4,000.
0 to 3000 is particularly preferred. The softening point is preferably at least 120C, more preferably from 120 to 145C. The specific gravity is preferably from 0.90 to 1.00, more preferably from 0.92 to 1.00, and particularly preferably from 0.95 to 1.00. Melting point (hereinafter, “melting point” in this specification refers to JIS K
The temperature at the top of the melting peak measured by DSC using the same method as that described in 7121. ) Is 1
The temperature is preferably from 00 to 130 ° C, particularly preferably from 120 to 130 ° C. In the adhesive of this embodiment, the above-mentioned (B) crystalline polypropylene wax having a softening point of 120 ° C. or more and / or “crystalline polyethylene wax” can be used alone or in combination.

In another preferred embodiment of the hot melt adhesive of the present invention, (B) 3 to 30% by weight of a crystalline polypropylene wax having a softening point of 120 ° C. or more and (C) ethylene content of 65% by weight or more A hot melt adhesive comprising from 2 to 41% by weight of a crystalline ethylene polymer obtained by polymerizing the above monomer. The adhesive of this embodiment preferably contains (B) 3 to 30% by weight of a crystalline polypropylene wax and (C) 2 to 41% by weight of a crystalline ethylene polymer. More preferably, it contains 5 to 20% by weight and 5 to 20% by weight of (C) a crystalline ethylene polymer,
It is particularly preferred to contain 5 to 15% by weight of crystalline polypropylene wax and 5 to 15% by weight of (C) a polymer of crystalline ethylene.

In the adhesive of this embodiment, (C) the crystalline ethylene polymer has a specific gravity of 0.9 or more and a melting point of 7
It preferably comprises a crystalline polyethylene having a temperature of 5 ° C. or higher. Here, “specific gravity is 0.9 or more, melting point is 75 ° C.
The properties of the above-mentioned crystalline polyethylene are not particularly limited as long as the desired performance of the present embodiment is exhibited, but the number average molecular weight is generally preferably 500 or more. The specific gravity (23 ° C.) is preferably 0.90 or more,
1.00 is more preferable, and 0.94 to 1.00 is particularly preferable. The melting point is preferably 75 ° C or higher, and 75 to 145 ° C
Is more preferable, and 120 to 145 ° C is particularly preferable. As such a crystalline ethylene polymer (C), a commercially available polymer can be used, and the crystalline ethylene polymer (C) can be used alone or in combination.

In the adhesive of this embodiment, the "(C) crystalline ethylene polymer" is a monomer having a content of ethylene of substantially 100% by weight (other monomers which are usually contained as impurities). In the case of crystalline polyethylene obtained by polymerizing (ethylene that may be contained), the melting point is 100 to 120 ° C
Is more preferred. The specific gravity is preferably from 0.90 to 1.00, more preferably from 0.92 to 1.00. MFR (melt flow rate) (Measurement is based on JIS K
The measurement was performed according to JIS K7210.
Condition 4 (measurement temperature 190 ° C., test load 2.16)
kgf). ) Is preferably 1 to 100 g, and 20
~ 80 g is more preferred. In the adhesive of this embodiment, “(C) crystalline ethylene polymer” is a monomer having a content of ethylene of preferably at least 65% by weight, more preferably at least 70% by weight, and the balance being vinyl acetate. In the case of an ethylene-vinyl acetate copolymer obtained by polymerizing a body mixture, the melting point is more preferably from 100 to 120C. The specific gravity is preferably 0.90 to 1.00, and 0.92 to 1.0.
0 is more preferred. MFR (measurement is JIS K6730
The measurement was performed according to Table 1 of JIS K7210.
Condition 4 is satisfied. ) Is preferably from 2 to 2500 g,
-500 g is more preferable, and 15-500 g is particularly preferable.

In the hot melt adhesive of the present invention,
Various "additives" commonly used in hot melt adhesives can further be included. Where "additives"
Is to improve the properties of hot melt adhesives comprehensively,
For maintaining the moldability of the filter and the quality of the filter after molding, for example, a stabilizer (antioxidant, etc.) for improving heat resistance, oxidation resistance and weather resistance, and preventing deterioration due to ultraviolet rays. UV absorbers, flame retardants,
At least one selected from an antiblocking agent for a hot melt adhesive and an inorganic filler for suppressing shrinkage can be exemplified.

As such additives, any commonly used additives can be used. As the antioxidant, for example, a phenol-based antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant are preferable. As the ultraviolet absorber, for example, benzophenone-based ultraviolet absorber,
Benzotriazole ultraviolet absorbers such as 2- (2-hydroxy-5-methylphenyl) benzotriazole are preferred. The above-mentioned additives can be used alone or as a mixture. In the hot melt adhesive of the present invention, the additive is preferably contained in an amount of 0.1 to 5 parts by weight, more preferably 0.2 to 4 parts by weight, based on 100 parts by weight of the hot melt adhesive. It is particularly preferred to contain from 3 to 3 parts by weight.

The above-mentioned hot melt adhesive of the present invention can be used in the field where the hot melt adhesive is usually used, for example, in the field of laminating and processing nonwoven fabric and / or paper. In particular, it is suitable for pleating a filter material such as non-woven cloth and / or paper for producing a filter and fixing the pleat to a frame material. Further, the hot melt adhesive of the present invention is used by setting it in a small-sized formwork, for example, for processing air filters, humidifiers, vacuum cleaners, filters for salt damage prevention equipment, etc. It is suitable for processing a filter that can be set. Further, the hot melt adhesive of the present invention has high water resistance, and thus can withstand use in water. In particular, the hot melt adhesive of the present invention can be suitably used when the filter medium is for a humidifier, an air purifier, a vacuum cleaner, or a salt damage prevention machine.

Further, by manufacturing the filter by using the hot melt adhesive of the present invention in the pleating process, the filter medium is formed in a pleated shape as a whole, and the thickness of the plate is pleated. It is possible to provide a filter which can be easily processed in a predetermined manner. The filter obtained in this way is
It may be further processed. That is, secondary processing may be performed. For example, it is possible to provide a filter that is formed into a cylindrical shape or a part thereof (semi-cylindrical shape) by bending a plate-shaped filter, or a secondary processed into a zigzag shape or a prism shape (half-square column shape) by bending. Furthermore, by using the hot melt adhesive of the present invention in pleating a filter medium to produce a filter, it is possible to provide a filter in which a packaging bag does not adhere to the pleated filter during transportation.

Further, when the hot melt adhesive of the present invention is used in pleating to produce a filter,
Since the open time of the hot melt adhesive of the present invention is short, the productivity of the filter can be improved.

[0039]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, these examples and comparative examples are merely one embodiment of the present invention, and the present invention is not limited by these examples. It is not something to be done.

The components (A) to (E) used for preparing the hot melt adhesives of Examples and Comparative Examples are shown below. (A
1) to (A4) are (A) amorphous olefin polymers, and (A1) has a number average molecular weight of 11,500, an elongation at break of 330%, a glass transition temperature of −33 ° C., An amorphous copolymer of propylene, ethylene and 1-butene having a softening point of 106 ° C., a viscosity of 8000 cps at 190 ° C., and a breaking strength of 10 kg / cm ² (Huels
s) Vestoplast 708 (trade name) manufactured by the company. (A2) has an elongation at break of 1050%,
Glass transition temperature -26 ° C, softening point 110 ° C, 190
Viscosity at 8000 cps and breaking strength of 13 kg /
cm ² copolymer of amorphous propylene and 1-butene (UBETAC 2780 manufactured by Ube Industries, Ltd.)
(Product name)). (A3) has an elongation at break of 690.
%, Glass transition temperature -27 ° C, softening point 141 ° C, 1
90 ℃ viscosity 8500cps, and breaking strength 7kg
/ Cm ² copolymer of amorphous propylene and ethylene (UBETAC 2385 manufactured by Ube Industries, Ltd.)
It is. (A4) is an amorphous ethylene having an elongation at break of 270%, a glass transition temperature of −35 ° C., a softening point of 129 ° C., a viscosity at 190 ° C. of 8,500 cps, and a breaking strength of 2 kg / cm ^2. It is a propylene copolymer (UBETAC 2585 manufactured by Ube Industries, Ltd.).

(B1) to (B3) have (B) a softening point of 1
A crystalline polypropylene wax of 20 ° C. or higher,
(B1) has a number average molecular weight of 4000 and a softening point of 150.
It is a crystalline polypropylene wax (Viscol 550P (trade name) manufactured by Sanyo Chemical Industries, Ltd.) having a degree of penetration of 1 ° C. or less and a viscosity of 200 cps at 160 ° C. (B2)
A crystalline polypropylene wax having a number average molecular weight of 3,000, a softening point of 145 ° C., a penetration of 1.5, and a viscosity of 70 cps at 160 ° C. (Viscol 66 manufactured by Sanyo Chemical Industries, Ltd.)
0P (product name)). (B3) has a number average molecular weight of 4000, a softening point of 150 ° C., a penetration of 1 or less, and 180.
Crystalline polypropylene wax having a viscosity at 150 ° C. and a melting point of 140 ° C. (High Wax N manufactured by Mitsui Chemicals, Inc.)
P-105 (product name)).

(C1) to (C4) are crystalline ethylene polymers obtained by polymerizing (C) a monomer having an ethylene content of 65% by weight or more. The number average molecular weight is 2200, the softening point is 136 ° C, the penetration is 1 or less, the viscosity at 140 ° C is 650 cps, the melting point is 126 ° C,
It is a crystalline polyethylene wax having a specific gravity of 0.98 (High Wax 400P (trade name) manufactured by Mitsui Chemicals, Inc.).
(C2) has a number average molecular weight of 1400 and a melting point of 126.
Crystalline polyethylene having a specific gravity of 0.935 and an MFR of 20 g (Nipolon LM70 (trade name) manufactured by Tosoh Corporation)
It is. (C3) is a crystalline polyethylene (Petrocene 249 (trade name) manufactured by Tosoh Corporation) having a number average molecular weight of 1400, a melting point of 102 ° C., a specific gravity of 0.916 and an MFR of 70 g. (C4) has a number average molecular weight of 2600
Ethylene-acetic acid obtained by polymerizing a monomer mixture having a melting point of 91 ° C., a specific gravity of 0.93, an MFR of 75 g, an ethylene content of 90% by weight, and a vinyl acetate content of 10% by weight. It is a vinyl copolymer (EV640 (trade name) manufactured by DuPont-Mitsui Polychemicals Co., Ltd.).

(D1) is a tackifying resin (D), and (D1) is a copolymer of completely hydrogenated dicyclopentadiene having a softening point of 90 ° C. and a styrene derivative (including styrene). (I-Merve P manufactured by Idemitsu Petrochemical Co., Ltd.
90 (product name)).

(E1) and (E2) are (E) waxes having a softening point of 70 ° C. or more and less than 120 ° C., and (E1)
Is a synthetic wax (Sasol H1 (trade name) manufactured by Sasol) manufactured by the Fischer-Tropsch method with a softening point of 108 ° C. and a penetration of 2. (E2) is
Microcrystalline wax having a softening point of 94 ° C. and a penetration of 19 (Nisseki 180 microwax (trade name) manufactured by Nippon Petrochemical Co., Ltd.).

Here, the physical properties (A) to (E) were evaluated using the following methods. The viscosities were measured at the indicated temperatures using a Brookfield viscometer (spindle 27). The penetration was measured at 25 ° C. using the same method as described in JIS K2207. The softening point was measured using a method similar to the method described in JIS K2207. The glass transition temperature is DIN 53765
And a differential scanning calorimeter (D)
SC), and indicated by the arithmetic mean temperature of the glass transition start temperature and the glass transition end temperature. Melting point is JIS
Using a method similar to that described in K7121, DSC
And indicated by the temperature at the top of the melting peak. The breaking strength and the breaking elongation were evaluated by measuring the force and elongation applied when a JIS No. 2 sample having a thickness of 2 mm was broken by pulling at a pulling speed of 50 mm / min. The specific gravity was measured at 23 ° C. using a method similar to the method described in JIS K6760. MFR (melt flow rate) is based on JIS for (C2) and (C3).
K6760 (measurement conditions are the conditions 4 in Table 1 of JIS K7210). Regarding (C4), JIS K6730 (measurement conditions are condition 4 in Table 1 of JIS K7210.)
The method was carried out in the same manner as described in (1).

Example 1 Preparation of Hot Melt Adhesive Number average molecular weight is 11,500, elongation at break is 330%, glass transition temperature is -33 ° C, softening point is 106 ° C, 190 ° C
Has a viscosity of 8000 cps and a breaking strength of 10 kg / c.
m ² amorphous copolymer of 1-butene (Hüls (H
Vestoplast 708 (trade name) (A1): 55% by weight A crystalline material having a number average molecular weight of 4000, a softening point of 150 ° C., a penetration of 1 or less, and a viscosity of 200 cps at 160 ° C. Polypropylene wax (Viscol 5 manufactured by Sanyo Chemical Industries, Ltd.)
50P (trade name) (B1): 30% by weight A copolymer of completely hydrogenated dicyclopentadiene having a softening point of 90 ° C. and a styrene derivative (including styrene) (Iemabu P90 manufactured by Idemitsu Petrochemical Co., Ltd.) (Product name))
(D1): Components (A1), (B1) and (D
1) was charged into a container, and uniformly mixed and dissolved while heating at 170 ° C. for 1 hour. A hot melt adhesive was obtained by adding 0.5 part by weight of a phenolic antioxidant (Sumilyzer BP101 (trade name) manufactured by Sumitomo Chemical Co., Ltd.) based on 100 parts by weight of this composition.

Evaluation of Hot Melt Adhesive (1) Viscosity of Hot Melt Adhesive The viscosity of the hot melt adhesive was measured at 150 ° C. and 160 ° C. using a Brookfield viscometer (spindle 27).
Was measured. The results are shown in Table 1. (2) Softening Point of Hot Melt Adhesive The softening point of the hot melt adhesive was measured by the R & B method (Japan Adhesive Industry Association Standard JAI 7). The results are shown in Table 1.

(3) Deformation of Hot Melt Adhesive at 80 ° C. To deform the hot melt adhesive at 80 ° C., a 1 cm square cube was formed using a hot melt adhesive, and this was attached to an aluminum plate. 4 hours after standing at 80 ° C for 6 hours
The corner deformation was evaluated by visual observation.も の indicates no deformation and X indicates deformation. The results are shown in Table 1.

[0049] (4) crooked of crooked hot melt adhesive of the hot melt adhesive was coated on Kraft paper at a coat weight of 1 g / m ² hot melt adhesive, 2
After 0 seconds, pleated molding of kraft paper was performed to prepare a sample filter. After the sample filter was allowed to stand at a predetermined temperature for 24 hours, the sample filter was vertically bent at a predetermined temperature from a crest to a valley at a 1 cm portion in a direction perpendicular to the coating direction. The evaluation was made by visually observing whether or not cracks occurred in the bonded portion between the hot melt adhesive and the kraft paper. The case where no crack occurred was evaluated as ○, and the case where cracks occurred or the hot melt adhesive peeled off from the kraft paper at the bonded portion was evaluated as ×. The results are shown in Table 1.

(5) Blocking resistance of hot-melt adhesive The blocking resistance of the hot-melt adhesive is determined by covering a ridge portion of the sample filter obtained by pleating with a polyethylene film and covering it with 1 g / cm. ^After applying a load of ² and standing at 80 ° C. or 70 ° C. for 24 hours, it was cooled to room temperature. 300 mm / m at 20 ° C. from a sample filter cut out to a width of 25 cm
The polyethylene film was peeled at a peel rate of "in", and the peel strength at that time was measured to evaluate. When the peel strength is 100 g / 25 mm or less,
○: 300 g / 25 mm and ×: 300 g / 25 mm or more. In addition, all the products with surface tack
And The results are shown in Table 1.

Examples 2 to 8 Examples 2 to 8 were prepared in the same manner as in Example 1 except that the components used in Example 1 were changed to the components and amounts shown in Table 1. ~ 8 hot melt adhesives were obtained. The hot melt adhesives of Examples 2 to 8 were evaluated using the same method as described in Example 1.
The results are shown in Table 1.

[0052]

[Table 1] The unit of composition is% by weight with the sum of components (A1) to (E2) being 100.

Comparative Examples 1 to 8 Comparative Examples 1 to 8 were used in the same manner as in Example 1 except that the components used in Example 1 were changed to the components and amounts shown in Table 2. ~ 8 hot melt adhesives were obtained. Using the same method as described in Example 1, the hot melt adhesives of Comparative Examples 1 to 8 were evaluated.
The results are shown in Table 2.

[0054]

[Table 2] The unit of the composition is% by weight with the sum of the components (A1) to (E2) being 100. -Indicates that evaluation was not possible.

Example 9 Example 9 was repeated except that the components used in Example 1 were changed to the components and amounts shown in Table 3.
The hot melt adhesive of Example 9 was obtained by using the same method as described above. For the viscosity and softening point, the hot melt adhesive of Example 9 was evaluated using the same method as described in Example 1. The open time was determined by using a filter molding line manufactured by Seiko Kikai Co., Ltd., and applying the hot melt adhesive of Example 9 to a nonwoven fabric at a coating amount of 1 g / m and a bead coating at a coating temperature of 150 ° C. Pleat molding
The measurement was performed by changing the line speed of the filter forming line at various values. Observe the bead shape of the formed filter visually and use the line speed when the bead shape changes from the state where the bead shape is maintained to the state where the bead shape is crushed, until the pleating after bead coating The open time was calculated by dividing the distance. The unit of the open time is seconds. The results are shown in Table 3.

Examples 10 to 12 In Examples 10 to 12, the components used in Example 1 were changed to the components shown in Table 3 and the amounts thereof.
The hot melt adhesives of Examples 10 to 12 were obtained in the same manner as in Example 1. Using the same method as described in Example 9, the hot melt adhesives of Examples 10 to 12 were evaluated. The results are shown in Table 3.

Comparative Example 9 Comparative Example 9 was conducted in the same manner as in Example 1 except that the components used in Example 1 were changed to the components and amounts shown in Table 3.
To obtain a hot melt adhesive of Comparative Example 9. Using a method similar to that described in Example 9,
The hot melt adhesive of Comparative Example 9 was evaluated. The results are shown in Table 3.

[0058]

[Table 3] The unit of the composition is% by weight with the sum of the components (A1) to (E1) being 100.

[0059]

Since the present invention is configured as described above, it has the following effects.

The hot melt adhesive according to the present invention comprises
(A) 50 to 90% by weight of an amorphous olefin copolymer (B) a crystalline polypropylene wax having a softening point of 120 ° C. or more and / or (C) a content of ethylene of 65%
5 to 44% by weight of a crystalline ethylene polymer obtained by polymerizing at least% by weight of a monomer, and 1 to 20% by weight of (D) a tackifier resin. It is possible to provide a hot melt adhesive having improved at least one property such as low viscosity at the time of processing, low temperature dependency of viscosity, and short open time.

Further, the hot melt adhesive of the present invention
Since the viscosity is low and the temperature dependence of the viscosity is small, when manufacturing a filter using pleating of filter media,
It is possible to provide a hot melt adhesive that can apply an adhesive to a filter medium at a low temperature and can also apply a filter medium that is weak to heat. Therefore, by using the hot melt adhesive according to the present invention for pleating, it is possible to provide a filter that is highly flexible and can be easily set in a small-sized mold.
Furthermore, it is possible to provide a filter formed in a secondary shape such as a cylindrical shape or a zigzag shape by combining both ends of the pleated filter medium. Furthermore, since the hot melt adhesive of the present invention has high water resistance, it can be used for processing a filter that can be used in a humid place, and can provide a filter with high water resistance.

The hot-melt adhesive according to the present invention contains 1 to 15% by weight of a wax having a low softening point having a softening point of 70 ° C. or more and less than 120 ° C., so that the hot-melt adhesive having good blocking resistance is provided. Can be provided. Therefore, for example, when a pleated filter is packaged and transported in a polyethylene bag or the like and transported, even if the temperature rises during transport, the filter adhesive does not substantially adhere to the packaging bag. Hot melt adhesives and filters can be provided. Furthermore, it is possible to provide a hot-melt adhesive that enables a pleated filter to be used at a high temperature and a filter that can be used at the high temperature.

Further, when the hot melt adhesive of the present invention is used in pleating to produce a filter,
Since the open time of the hot melt adhesive of the present invention is short, the productivity of the filter can be improved.

Claims (12)

[Claims] (A) Amorphous olefin polymer: 50
(B) crystalline polypropylene wax having a softening point of 120 ° C. or more and / or (C) ethylene content of 65% by weight.
Crystalline ethylene polymer obtained by polymerizing the above monomers: 5 to 44% by weight, and (D) tackifying resin: 1
A hot melt adhesive comprising ２０20% by weight. 2. The polymer (A) of an amorphous olefin,
At least one amorphous 1 selected from a copolymer of propylene and 1-butene, a copolymer of ethylene and 1-butene, and a copolymer of propylene and ethylene and 1-butene;
-Is a copolymer of butene, and is a copolymer of amorphous 1-butene, which may include at least one selected from amorphous polypropylene and a copolymer of amorphous ethylene and propylene. The hot melt adhesive according to claim 1. 3. An amorphous 1-butene copolymer having a number average molecular weight of 4,000 to 25,000 and an elongation at break of 100.
%, A glass transition temperature of -20 to -40 ° C, and 19
The hot melt adhesive according to claim 2, having a viscosity at 0 ° C of 1500 to 50,000 cps. 4. The (D) tackifying resin is a partially or completely hydrogenated tackifying resin, wherein the partially or completely hydrogenated dicyclopentadiene polymer and / or dicyclopentadiene is used. The hot melt adhesive according to any one of claims 1 to 3, which is at least one kind of a copolymer of styrene and a styrene derivative (including styrene). 5. The hot melt adhesive according to claim 1, further comprising 1 to 15% by weight of (E) a wax having a softening point of 70 ° C. or more and less than 120 ° C. 6. The crystalline ethylene polymer (C) is a crystalline polyethylene wax, and (B) the softening point is 120.
5 ° C. or more of the crystalline polypropylene wax and / or (C) the crystalline polyethylene wax content is 5 to 30.
The hot-melt adhesive according to any one of claims 1 to 5, which is% by weight. 7. The crystalline polypropylene wax (B) having a softening point of 120 ° C. or higher has a number average molecular weight of 2,000 to 20.
7. The hot melt adhesive according to claim 6, wherein the penetration is 2 or less, and the number average molecular weight of the crystalline polyethylene wax (C) is 1,000 to 10,000. 8. The composition according to claim 1, comprising (B) 3 to 30% by weight of a crystalline polypropylene wax having a softening point of 120 ° C. or higher and (C) 2 to 41% by weight of a crystalline ethylene polymer. The hot melt adhesive according to any one of the above. 9. The hot melt adhesive according to claim 8, comprising (C) a crystalline ethylene polymer comprising crystalline polyethylene having a specific gravity of 0.9 or more and a melting point of 75 ° C. or more. 10. The hot melt adhesive according to claim 1, which is used for pleating a filter medium to produce a filter. 11. A filter produced by using the hot melt adhesive according to claim 1 for pleating a filter medium. 12. The filter according to claim 11, wherein the pleated filter medium is formed into a cylindrical shape by joining both ends thereof, or the pleated filter medium is zigzag-shaped or the like.