WO2020066791A1

WO2020066791A1 - Hot melt adhesive composition

Info

Publication number: WO2020066791A1
Application number: PCT/JP2019/036581
Authority: WO
Inventors: 祥史丸山; 貞治橋本; 涼嗣亀山
Original assignee: 日本ゼオン株式会社
Priority date: 2018-09-27
Filing date: 2019-09-18
Publication date: 2020-04-02
Also published as: JP7468348B2; JPWO2020066791A1; CN112703236A

Abstract

The present invention provides a hot melt adhesive composition which contains a modified hydrocarbon resin and a thermoplastic elastomer, and which is configured such that: the modified hydrocarbon resin is obtained by introducing a carboxyl group or an acid anhydride group derived from an unsaturated carboxylic acid or an unsaturated dicarboxylic acid anhydride into a resin that is obtained by hydrogenating a hydrocarbon resin that contains 20-70% by mass of a 1, 3-pentadiene monomer unit, 10-50% by mass of an alicyclic monoolefin monomer unit having 4-6 carbon atoms, 5-40% by mass of an acyclic monoolefin monomer unit having 4-8 carbon atoms, 0-1% by mass of an alicyclic diolefin monomer unit and 0-40% by mass of an aromatic monoolefin monomer unit; and the modified hydrocarbon resin has an iodine number within the range of 45-125 gI₂/100 g.

Description

Hot melt adhesive composition

The present invention relates to a hot-melt pressure-sensitive adhesive composition, and more particularly, to a hot-melt pressure-sensitive adhesive composition having high adhesion performance, excellent hue and heat-resistant hue stability, and low odor.

Hot-melt adhesives can solidify in a short period of time, enabling efficient bonding of various products, and since they do not require solvents, they are highly adhesive to humans. Since it is an adhesive, it is used in various fields. For example, when manufacturing paper, corrugated cardboard, sealing adhesive for packaging films, hygiene products such as disposable diapers and sanitary products, food, clothing, electronic equipment, cosmetics, etc. Hot-melt adhesives have been awarded as adhesives for forming adhesive layers and as adhesives constituting adhesive layers of adhesive tapes and labels.

Hot melt adhesives are usually produced by blending a tackifying resin or the like with a base polymer. In recent years, an attempt to use a modified hydrocarbon resin obtained by allowing an acid or an acid anhydride to act on a hydrocarbon resin has attracted attention as a tackifier resin. It is known that such a modified hydrocarbon resin can provide a hot melt adhesive with novel properties (for example, water-resistant adhesiveness) that are not present in conventional tackifying resins.

For example, Patent Document 1 discloses a hydrocarbon obtained by copolymerizing 100 parts by weight of a vinyl aromatic hydrocarbon and 5 to 100 parts by weight of a hydrocarbon component mainly composed of an unsaturated hydrocarbon having 4 to 5 carbon atoms. Disclosed is a modified hydrocarbon resin having an acid value of 1 to 150 (mgKOH / g) and a weight average molecular weight of 300 to 5000, which is obtained by graft copolymerizing at least one kind selected from monoolefin dicarboxylic acid and its anhydride on the resin. Have been. However, the modified hydrocarbon resin is effective for an adhesive using some acrylic base polymers, but is not compatible with an adhesive using an ethylene base polymer or a rubber base polymer. Bad, not enough adhesion. Further, since the copolymerization amount of the vinyl aromatic hydrocarbon is large, odor due to the residual monomer is also a problem.

Further, Patent Document 2 includes a reaction product such as an unsaturated aliphatic hydrocarbon monomer having 5 carbon atoms, an isoolefin monomer, and a dicarboxylic acid or an acid anhydride, and has a predetermined acid value and a predetermined composition ratio. An acid-modified hydrocarbon resin having the same is disclosed. However, the acid-modified hydrocarbon resin has a very bad hue and has a problem of odor at a high temperature in a hot melt state.

JP-A-7-188352 JP-T-2004-502839

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a hot-melt adhesive composition having high adhesive performance, excellent hue and heat-resistant hue stability, and low odor. With the goal.

The present inventors have studied to achieve the above object, and obtained by further acid-modifying a resin obtained by hydrogenating a hydrocarbon resin having a specific composition so as to have a specific iodine value range. It has been found that by combining the modified hydrocarbon resin obtained with a thermoplastic elastomer, a hot melt adhesive composition having high adhesive performance, excellent hue and heat stability, and low odor can be obtained. It was completed.

That is, according to the present invention, a modified hydrocarbon resin, a hot melt adhesive composition containing a thermoplastic elastomer,
The modified hydrocarbon resin,
20 to 70% by mass of 1,3-pentadiene monomer unit,
An alicyclic monoolefin monomer unit having 4 to 6 carbon atoms, 10 to 50% by mass,
An acyclic monoolefin monomer unit having 4 to 8 carbon atoms, 5 to 40% by mass,
An unsaturated carboxylic acid or unsaturated resin is added to a resin obtained by hydrogenating a hydrocarbon resin containing 0 to 1% by mass of an alicyclic diolefin monomer unit and 0 to 40% by mass of an aromatic monoolefin monomer unit. A carboxyl group or an acid anhydride group derived from a dicarboxylic acid anhydride is introduced,
The modified hot melt adhesive composition iodine value of the hydrocarbon resin is in the range of 45 _~ 125gI 2 / 100g is provided.

In the hot melt adhesive composition of the present invention, the modified hydrocarbon resin has a weight average molecular weight (Mw) in the range of 1,000 to 5,000, and a Z average molecular weight (Mz) of 1,500. １２12,500, the ratio of the Z average molecular weight to the weight average molecular weight (Mz / Mw) is within the range of 1.5 ～ 2.5, and the Gardner color number of the 50% by mass toluene solution is 5 or less. It is preferable that the softening point is 30 ° C. or higher and the acid value is 0.5 to 20 KOH mg / g.
In the hot melt adhesive composition of the present invention, the unsaturated dicarboxylic anhydride is preferably maleic anhydride.
In the hot melt adhesive composition of the present invention, the total content of the unreacted unsaturated carboxylic acid and the unreacted unsaturated dicarboxylic anhydride in the modified hydrocarbon resin is 3000 ppm by weight or less. It is preferred that
In the hot melt adhesive composition of the present invention, the thermoplastic elastomer may be at least one selected from an ethylene-vinyl acetate copolymer, a styrene-based thermoplastic elastomer, and a polyolefin-based thermoplastic elastomer. preferable.

According to the present invention, it is possible to provide a hot-melt adhesive composition having high adhesive performance, excellent hue and heat-resistant hue stability, and low odor.

The hot melt adhesive composition of the present invention contains a modified hydrocarbon resin and a thermoplastic elastomer.
Hereinafter, each component of the hot melt adhesive composition of the present invention will be described.

<Modified hydrocarbon resin>
Modified hydrocarbon resin used in the present invention,
20 to 70% by mass of 1,3-pentadiene monomer unit,
An alicyclic monoolefin monomer unit having 4 to 6 carbon atoms, 10 to 50% by mass,
An acyclic monoolefin monomer unit having 4 to 8 carbon atoms, 5 to 40% by mass,
An unsaturated carboxylic acid or unsaturated resin is added to a resin obtained by hydrogenating a hydrocarbon resin containing 0 to 1% by mass of an alicyclic diolefin monomer unit and 0 to 40% by mass of an aromatic monoolefin monomer unit. A carboxyl group or an acid anhydride group derived from a dicarboxylic acid anhydride is introduced,
The iodine value is in the range of 45 _~ 125gI 2 / 100g.

The modified hydrocarbon resin used in the present invention is obtained by further hydrogenating a resin obtained by hydrogenating a hydrocarbon resin having the above specific composition.
In the following, first, a hydrocarbon resin before acid modification and before hydrogenation (hereinafter sometimes simply referred to as a resin before modification) will be described in detail, and then the resin before modification is hydrogenated. The modified hydrocarbon resin obtained by further acid-modifying the resin will be described.

<Before modification>
The resin before modification is a raw material resin before acid modification and before hydrogenation, and is an alicyclic monoolefin monomer unit having 20 to 70% by mass of 1,3-pentadiene monomer unit and 4 to 6 carbon atoms. 10 to 50% by mass, C4 to C8 acyclic monoolefin monomer unit 5 to 40% by mass, alicyclic diolefin monomer unit 0 to 1% by mass, and aromatic monoolefin monomer It contains a unit of 0 to 40% by mass.
The content ratio of the monomer unit is the same in the modified hydrocarbon resin, and the preferable range of the content ratio is the same as that of the resin before modification.

The content of the 1,3-pentadiene monomer unit in the resin before modification may be in the range of 20 to 70% by mass, preferably in the range of 25 to 65% by mass, and more preferably 30 to 65% by mass. It is preferably in the range of 60 to 60% by mass, more preferably in the range of 35 to 55% by mass, and particularly preferably in the range of 40 to 50% by mass. If the amount of the 1,3-pentadiene monomer unit in the unmodified resin is too small, the resulting hot-melt adhesive composition will be inferior in heat deterioration resistance. On the other hand, when the 1,3-pentadiene monomer unit amount in the resin before modification is too large, the softening point of the modified hydrocarbon resin becomes high, and the obtained hot melt adhesive composition has a short open time, Adhesive strength is low, resulting in poor coating easiness. The cis / trans isomer ratio in the 1,3-pentadiene monomer unit may be any ratio, and is not particularly limited.

The alicyclic monoolefin having 4 to 6 carbon atoms is a hydrocarbon compound having 4 to 6 carbon atoms having one ethylenically unsaturated bond and a non-aromatic ring structure in its molecular structure. Specific examples of the alicyclic monoolefin having 4 to 6 carbon atoms include cyclobutene, cyclopentene, cyclohexene, methylcyclobutene, methylcyclopentene and the like.

The content of the alicyclic monoolefin monomer unit having 4 to 6 carbon atoms in the resin before modification may be in the range of 10 to 50% by mass, and is in the range of 15 to 50% by mass. It is preferably in the range of 19 to 50% by mass, more preferably in the range of 23 to 50% by mass, and particularly preferably in the range of 24 to 40% by mass. If the amount of the alicyclic monoolefin monomer having 4 to 6 carbon atoms in the resin before modification is too small, the softening point of the modified hydrocarbon resin becomes high, and the resulting hot melt adhesive composition becomes open. The time is short, the adhesive strength is low, and the coating is poor. On the other hand, if the amount of the alicyclic monoolefin monomer having 4 to 6 carbon atoms in the resin before modification is too large, the resulting hot melt adhesive composition will have poor heat deterioration resistance.

The ratio of each compound corresponding to the alicyclic monoolefin having 4 to 6 carbon atoms may be an arbitrary ratio, and is not particularly limited, but it is preferable that at least cyclopentene is contained, and that the number of carbon atoms is 4 to 6 carbon atoms. It is more preferable that the proportion of cyclopentene in the alicyclic monoolefin is 50 mass% or more.

非 Acyclic monoolefin having 4 to 8 carbon atoms is a chain hydrocarbon compound having 4 to 8 carbon atoms and having one ethylenically unsaturated bond in its molecular structure and having no ring structure. Specific examples of the acyclic monoolefin having 4 to 8 carbon atoms include butenes such as 1-butene, 2-butene and isobutylene (2-methylpropene); 1-pentene, 2-pentene and 2-methyl-1 -Pentenes such as -butene, 3-methyl-1-butene and 2-methyl-2-butene; hexenes such as 1-hexene, 2-hexene and 2-methyl-1-pentene; 1-heptene and 2-heptene , Such as 1-octene, 2-octene, 2-methyl-1-heptene, diisobutylene (2,4,4-trimethyl-1-pentene, 2,4,4- Octenes such as trimethyl-2-pentene); and the like.

The content of the acyclic monoolefin monomer unit having 4 to 8 carbon atoms in the resin before modification may be within the range of 5 to 40% by mass, and within the range of 5 to 35% by mass. It is preferably in the range of 5 to 30% by mass, more preferably in the range of 5 to 25% by mass, and particularly preferably in the range of 5 to 15% by mass. If the amount of the acyclic monoolefin monomer having 4 to 8 carbon atoms in the resin before modification is too small, the softening point of the modified hydrocarbon resin becomes high, and the resulting hot-melt adhesive composition becomes open. The time is short, the adhesive strength is low, and the coating is poor. On the other hand, if the amount of the acyclic monoolefin monomer having 4 to 8 carbon atoms in the resin before modification is too large, the obtained hot melt adhesive composition will have poor heat deterioration resistance.

As the acyclic monoolefin having 4 to 8 carbon atoms, the ratio of each of the corresponding compounds (including isomers) may be an arbitrary ratio, and is not particularly limited, but is at least 2-methyl-2-butene. And at least one selected from the group consisting of isobutylene and diisobutylene, and the total amount of 2-methyl-2-butene, isobutylene and diisobutylene in the acyclic monoolefin having 4 to 8 carbon atoms Is more preferably 50% by mass or more.

The resin before modification used in the present invention may contain an alicyclic diolefin as a raw material. An alicyclic diolefin is a hydrocarbon compound having two or more ethylenically unsaturated bonds and a non-aromatic ring structure in its molecular structure. Specific examples of the alicyclic diolefin include a polymer of cyclopentadiene such as cyclopentadiene and dicyclopentadiene, a polymer of methylcyclopentadiene, and a polymer of methylcyclopentadiene.

The content of the alicyclic diolefin monomer unit in the resin before modification may be in the range of 0 to 1% by mass, preferably in the range of 0 to 0.8% by mass. However, it is preferably in the range of 0 to 0.6% by mass, more preferably in the range of 0 to 0.4% by mass, and particularly preferably in the range of 0.01 to 0.4% by mass. preferable. When the content is within the above range, the obtained hot melt adhesive composition can have low odor.

The resin before modification used in the present invention may contain an aromatic monoolefin as a raw material. An aromatic monoolefin is an aromatic compound having one ethylenically unsaturated bond in its molecular structure. Specific examples of the aromatic monoolefin include styrene, α-methylstyrene, vinyltoluene, indene, cumarone, and the like.

The content of the aromatic monoolefin monomer unit in the resin before modification may be in the range of 0 to 40% by mass, preferably in the range of 0 to 38% by mass, and more preferably 0 to 38% by mass. It is preferably in the range of 36% by mass, more preferably in the range of 0 to 34% by mass, and particularly preferably in the range of 3 to 28% by mass. When the content is within the above range, the obtained hot melt adhesive composition can have a low odor and an excellent color tone.

The ratio of each compound (including isomers) corresponding to the aromatic monoolefin may be an arbitrary ratio, and is not particularly limited, but it is preferable that at least styrene is contained, and styrene is contained in the aromatic monoolefin. Is more preferably 50% by mass or more.

The pre-modified resin used in the present invention includes a 1,3-pentadiene monomer unit, an alicyclic monoolefin monomer unit having 4 to 6 carbon atoms, and an acyclic monoolefin monomer unit having 4 to 8 carbon atoms. In addition to the alicyclic diolefin monomer unit and the aromatic monoolefin monomer unit, other monomer units may be contained as long as the effects of the present invention can be obtained.

The other monomer used to constitute such another monomer unit is a compound other than the above-mentioned monomer, and is an addition-polymerizable compound which can be addition-copolymerized with 1,3-pentadiene or the like. Is not particularly limited as long as the compound has Examples of the other monomers include those having 4 to 6 carbon atoms other than 1,3-pentadiene such as 1,3-butadiene, 1,2-butadiene, isoprene, 1,3-hexadiene, and 1,4-pentadiene. Unsaturated hydrocarbons having 7 or more carbon atoms such as cycloheptene; acyclic monoolefins having 4 to 8 carbon atoms such as ethylene, propylene and nonene; and the like.

The content of the other monomer units in the pre-modified resin is not particularly limited as long as the effects of the present invention can be obtained, and is preferably in the range of 0 to 30% by mass. The content is more preferably in the range of 0 to 25% by mass, and even more preferably in the range of 0 to 20% by mass. If the content is too large, the resulting hot melt adhesive composition may have a short open time and a reduced adhesive strength.

The method for producing the resin before modification is not particularly limited as long as the polymerizable component (monomer mixture A) having each monomer capable of constituting each monomer unit described above is suitably subjected to addition polymerization. Not done. For example, a pre-modified resin can be obtained by addition polymerization using a Friedel-Crafts type cationic polymerization catalyst.

Examples of the method preferably used for producing the unmodified resin include, for example, the following aluminum halide (A), halogenated hydrocarbon (B1) having a tertiary carbon atom bonded to a halogen atom, and carbon- A polymerization catalyst is prepared by combining a halogenated hydrocarbon (B) selected from the group consisting of a halogenated hydrocarbon (B2) in which a halogen atom is bonded to a carbon atom adjacent to a carbon unsaturated bond to form 1,3-pentadiene 20 70 to 70% by mass, 10 to 50% by mass of an alicyclic monoolefin having 4 to 6 carbon atoms, 5 to 40% by mass of an acyclic monoolefin having 4 to 8 carbon atoms, 0 to 1% by mass of an alicyclic diolefin, And a method having a polymerization step of polymerizing a monomer mixture A containing 0 to 40% by mass of an aromatic monoolefin.

Specific examples of the aluminum halide (A) include aluminum chloride (AlCl ₃ ) and aluminum bromide (AlBr ₃ ). Among them, aluminum chloride is preferably used from the viewpoint of versatility and the like.

The amount of the aluminum halide (A) is not particularly limited, but is preferably in the range of 0.05 to 10 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the polymerizable component (monomer mixture A). It is within the range of 1 to 5 parts by mass.

In addition, in the polymerization, by using the halogenated hydrocarbon (B) in combination with the aluminum halide (A), the activity of the polymerization catalyst becomes extremely good.

Specific examples of the halogenated hydrocarbon (B1) in which a halogen atom is bonded to a tertiary carbon atom as the halogenated hydrocarbon (B) include t-butyl chloride, t-butyl bromide, 2-chloro-2-methylbutane And triphenylmethyl chloride. Among them, t-butyl chloride is particularly preferably used because of its excellent balance between activity and ease of handling.

Examples of the unsaturated bond in the halogenated hydrocarbon (B2) in which a halogen atom is bonded to a carbon atom adjacent to the carbon-carbon unsaturated bond as the halogenated hydrocarbon (B) include a carbon-carbon double bond and a carbon-carbon double bond. It includes a carbon triple bond, and also includes a carbon-carbon conjugated double bond in an aromatic ring or the like. Specific examples of such compounds include benzyl chloride, benzyl bromide, (1-chloroethyl) benzene, allyl chloride, 3-chloro-1-propyne, 3-chloro-1-butene, 3-chloro-1-butyne, Cinnamon chloride and the like. Among these, benzyl chloride is preferably used because it has an excellent balance between activity and ease of handling.

The halogenated hydrocarbon (B) may be used alone or in combination of two or more.

The amount of the halogenated hydrocarbon (B) used is preferably in the range of 0.05 to 50, more preferably in the range of 0.1 to 10, in terms of a molar ratio to the aluminum halide (A).

In performing the polymerization reaction, the order in which the respective components of the monomer mixture and the polymerization catalyst are added to the polymerization reactor is not particularly limited, and may be added in any order. From the viewpoint of obtaining a modified hydrocarbon resin having more excellent hue, the monomer mixture and a part of the components of the polymerization catalyst are added to the polymerization reactor, and after the polymerization reaction is started, the remainder of the polymerization catalyst is subjected to the polymerization reaction. It is preferred to add to the vessel.

Specifically, in the production of the resin before modification, it is preferable to first mix the aluminum halide (A) and the alicyclic monoolefin in advance. By performing a contact treatment in which the aluminum halide (A) and the alicyclic monoolefin are mixed in advance, formation of a gel can be prevented, and a pre-modified resin having an excellent hue can be suitably obtained.

量 The amount of the alicyclic monoolefin mixed with the aluminum halide (A) is preferably at least 5 times (by mass) the amount of the aluminum halide (A). If the amount of the alicyclic monoolefin is too small, the effects of preventing gel formation and improving hue may be reduced. The mass ratio of the alicyclic monoolefin to the aluminum halide (A) is preferably the mass ratio of “alicyclic monoolefin: aluminum halide (A)”, and more preferably 5: 1 to 120: 1. The ratio is from 10: 1 to 100: 1, more preferably from 15: 1 to 80: 1. If an alicyclic monoolefin is used in an amount larger than this ratio, the catalytic activity may decrease, and the polymerization may not proceed sufficiently.

When the aluminum halide (A) and the alicyclic monoolefin are preliminarily mixed, the order of charging them is not particularly limited, and the aluminum halide (A) may be charged into the alicyclic monoolefin, Conversely, an alicyclic monoolefin may be introduced into the aluminum halide (A). Since mixing is usually exothermic, a suitable diluent can be used. As a diluent, a solvent described below can be used.

After preparing the mixture M of the aluminum halide (A) and the alicyclic monoolefin as described above, the mixture M containing at least 1,3-pentadiene and the acyclic monoolefin is mixed with the mixture M. Is preferred. The mixture a may contain an alicyclic diolefin and / or an aromatic monoolefin.

The method for preparing the mixture a is not particularly limited, and each of the pure compounds may be mixed to obtain the desired mixture a, or may contain the desired monomer derived from, for example, a naphtha decomposition product fraction. The desired mixture a may be obtained using the mixture. For example, in order to mix 1,3-pentadiene and the like into the mixture a, a C5 fraction after extracting isoprene and cyclopentadiene (including a multimer thereof) can be suitably used.

と共に It is preferable to further mix the halogenated hydrocarbon (B) together with the mixture a and the mixture M. The order of input of these three is not particularly limited.

から From the viewpoint of better controlling the polymerization reaction, it is preferable to carry out the polymerization reaction by adding a solvent to the polymerization reaction system. The type of the solvent is not particularly limited as long as it does not inhibit the polymerization reaction, but a saturated aliphatic hydrocarbon or an aromatic hydrocarbon is preferable. Examples of the saturated aliphatic hydrocarbon used as a solvent include n-pentane, n-hexane, 2-methylpentane, 3-methylpentane, n-heptane, 2-methylhexane, 3-methylhexane, and 3-ethylpentane Carbon number such as 2,2-dimethylpentane, 2,3-dimethylpentane, 2,4-dimethylpentane, 3,3-dimethylpentane, 2,2,3-trimethylbutane, 2,2,4-trimethylpentane A chain saturated aliphatic hydrocarbon having 5 to 10 carbon atoms; a cyclic saturated aliphatic hydrocarbon having 5 to 10 carbon atoms such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane. Examples of the aromatic hydrocarbon used as a solvent include aromatic hydrocarbons having 6 to 10 carbon atoms, such as benzene, toluene, and xylene. The solvent may be used alone or as a mixed solvent of two or more.

The amount of the solvent to be used is not particularly limited, but is preferably within a range from 10 to 1,000 parts by mass, and preferably from 50 to 500 parts by mass, per 100 parts by mass of the polymerizable component (monomer mixture A). More preferably, it is within the range. In addition, for example, a mixture of an addition-polymerizable component and a non-addition-polymerizable component, such as a mixture of cyclopentane and cyclopentene derived from the C5 fraction, is added to the polymerization reaction system, and the addition-polymerizable component is converted into a single monomer. It can be used as a component of a body mixture, and the non-addition polymerizable component can be used as a solvent.

重合 The polymerization temperature at the time of performing the polymerization reaction is not particularly limited, but is preferably in the range of −20 ° C. to 100 ° C., and more preferably in the range of 10 ° C. to 70 ° C. If the polymerization temperature is too low, the polymerization activity may be reduced and the productivity may be inferior. If the polymerization temperature is too high, the color of the unmodified resin obtained may be inferior. The pressure at which the polymerization reaction is performed may be under atmospheric pressure or under pressure. The polymerization reaction time can be appropriately selected, and is usually selected in the range of 10 minutes to 12 hours, preferably 30 minutes to 6 hours.

The polymerization reaction can be stopped by adding a polymerization terminator such as methanol, sodium hydroxide aqueous solution or aqueous ammonia solution to the polymerization reaction system when a desired polymerization conversion is obtained.

において In the method for producing a pre-modified resin, it is sufficient that the method includes at least the polymerization step. However, if necessary, the method may include other steps.

As other steps, for example, after the polymerization step, a polymerization terminator is added in the polymerization step to remove the catalyst residue which is generated when the polymerization catalyst is inactivated and which is insoluble in the solvent, is removed by filtration or the like. After the polymerization reaction is stopped by the step or the polymerization step, the unreacted monomers and the solvent are removed, the low molecular weight oligomer component is further removed by steam distillation or the like, and the solid unmodified resin is cooled by cooling. And the like.

Further, as another step, after the catalyst residue removal step and before the recovery step, the catalyst residue removal mixture after removing the catalyst residue insoluble in the solvent is brought into contact with the adsorbent to obtain an adsorbent-treated mixture. A processing step may be provided. By providing the contact treatment step, the resin before modification and the modified hydrocarbon resin obtained by further acid-modifying the resin obtained by hydrogenating the resin before modification can have a lower odor.

The above other steps may be performed after the hydrogenation step or the acid modification step in the method for producing a modified hydrocarbon resin described below.

The adsorbent used in the contacting step is not particularly limited, and may be a chemical adsorbent or a physical adsorbent.

Examples of the chemical adsorbent include zinc-based adsorbents such as basic zinc carbonate, zinc oxide, zinc sulfate, zinc laurate, zinc stearate, and zinc myristate; and zirconium oxide, zirconium hydroxide, and zirconium phosphate. A manganese-based adsorbent such as manganese dioxide; a cobalt-based adsorbent such as cobalt chloride; a copper-based adsorbent such as copper chloride and copper oxide; and an amine-based adsorbent such as a polyamine compound.

Examples of the physical adsorbent include zeolite-based adsorbents collectively referred to as a hydrous aluminosilicate mineral group such as sodium aluminum silicate, silicon dioxide, magnesium oxide, silica gel, silica / alumina, aluminum silicate, activated alumina, and acid clay. Activated clay, dawsonite compounds, hydrotalcite compounds and the like.

The adsorbent may be used alone or in combination of two or more. When two or more adsorbents are used in combination, two or more chemical adsorbents may be used in combination, two or more physical adsorbents may be used in combination, and one or more chemical adsorbents may be used. The agent and one or more physical adsorbents may be used in combination. For example, a physical adsorbent may carry a chemical adsorbent. In particular, from the viewpoint of obtaining a pre-modified resin and a modified hydrocarbon resin excellent in low odor, among these adsorbents, it is preferable to use a chemical adsorbent, and it is more preferable to use a zinc-based adsorbent, It is particularly preferred to use basic zinc carbonate.

方法 In the above-mentioned contact treatment step, the method of contacting the catalyst residue removal mixture with the adsorbent is not particularly limited. For example, the catalyst residue removal mixture and the adsorbent are allowed to coexist in an appropriately selected container, and the mixture is agitated as necessary, and is brought into contact with a batch processing method, or the adsorbent is filled in a packed tower in advance, and And a continuous treatment method in which a catalyst residue removal mixture is passed through and brought into contact.

When the catalyst residue removal mixture and the adsorbent are brought into contact with each other by a batch treatment method, the amount of the adsorbent used is not particularly limited, but is usually 0.1 to 100 parts by mass of the unmodified resin contained in the catalyst residue removal mixture. It is in the range of 01 to 5.0 parts by mass, preferably in the range of 0.03 to 3.0 parts by mass, and more preferably in the range of 0.05 to 2.0 parts by mass. Is within.

温度 The temperature at which the catalyst residue removal mixture is brought into contact with the adsorbent is not particularly limited, but is usually selected within the range of 10 ° C to 70 ° C. The processing time is also not particularly limited, but is usually selected within a range of 0.1 to 2 hours.

(4) When the catalyst residue removal mixture and the adsorbent are brought into contact by a batch treatment method, the adsorbent can be removed from the catalyst residue removal mixture by filtration or the like, if necessary. When there is no problem in using the pre-modified resin and the modified hydrocarbon resin even if the adsorbent remains, the adsorbent may be used in the next step without removing the adsorbent from the catalyst residue removal mixture.

<Modified hydrocarbon resin>
The modified hydrocarbon resin used in the present invention is a modified hydrocarbon resin obtained by further acid-modifying a resin obtained by hydrogenating the above resin before modification.

Modified hydrocarbon resin is in the range of iodine value 45 _~ 125gI 2 / 100g. The iodine value is an index indicating the content of a non-hydrogenated non-aromatic carbon-carbon double bond contained in the modified hydrocarbon resin, and can be measured, for example, in accordance with JIS K0070. it can.

Modified hydrocarbon resin used in the present invention may be within the range of iodine value 45 _~ 125gI 2 / 100g, preferably in the range of 50 _~ 120gI 2 / 100g, among others 55 ~ 115gI ₂ / preferably 100g in the range of, particularly preferably in the range of 60 _~ 110gI 2 / 100g. According to the present invention, when the iodine value is within the above range, the obtained hot melt adhesive composition can have a low odor and a small change in hue due to thermal deterioration or the like. On the other hand, if the iodine value is too low, it becomes difficult to react the hydrogenated resin with the unsaturated carboxylic acid or the unsaturated dicarboxylic anhydride with the hydrogenated resin to acid-modify the resin. A large amount of the unsaturated carboxylic acid and the unsaturated dicarboxylic anhydride in the reaction remain, and the hot-melt pressure-sensitive adhesive composition finally obtained is inferior in adhesive performance and becomes strong in odor.

The modified hydrocarbon resin used in the present invention may have an iodine value within the above range, but the hydrogenation rate of the olefin (hereinafter sometimes simply referred to as hydrogenation rate) is 0.1% to 80. %, More preferably in the range of 1% to 70%, even more preferably in the range of 5% to 60%, and more preferably in the range of 10% to 50%. Is more preferable. In addition, the hydrogenation rate of the olefin means a ratio of hydrogenated one among all non-aromatic carbon-carbon double bonds of the resin before modification.

The carbon-carbon double bond in the resin before modification includes a non-aromatic carbon-carbon double bond (mainly a carbon-carbon double bond in the main chain) and an aromatic carbon-carbon double bond. Although there is a heavy bond (carbon-carbon double bond in the aromatic ring), it is preferable that the aromatic carbon-carbon double bond is not hydrogenated as much as possible. Among them, the hydrogenated ratio is preferably 10% or less, more preferably 7% or less, and further preferably 0%.

The hydrogenation rate of the olefin can be determined from the difference between the olefin amounts of the resin before modification and the modified hydrocarbon resin. Here, the olefin content of each resin can be determined by ¹ H-NMR spectrum measurement. ¹ H-NMR spectrum measurement can be performed using deuterated chloroform as a solvent, and using JMN-AL series AL400, manufactured by JEOL as an NMR measuring apparatus.

The modified hydrocarbon resin used in the present invention has a carboxyl group or an acid anhydride group derived from an unsaturated carboxylic acid or an unsaturated dicarboxylic acid anhydride.

Examples of unsaturated carboxylic acids include ethylenically unsaturated carboxylic acids having 8 or less carbon atoms, such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid and citraconic acid; 3,6-endomethylene-1, A Diels-Alder adduct of a conjugated diene such as 2,3,6-tetrahydrophthalic acid with an α, β-unsaturated dicarboxylic acid having 8 or less carbon atoms;

Examples of unsaturated dicarboxylic anhydrides include α, β-unsaturated dicarboxylic anhydrides having 8 or less carbon atoms, such as maleic anhydride, itaconic anhydride and citraconic anhydride; 3,6-endomethylene-1,2,3 A Diels-Alder adduct of a conjugated diene such as 2,6-tetrahydrophthalic anhydride with an α, β-unsaturated dicarboxylic anhydride having 8 or less carbon atoms.

Α From the viewpoints of easiness of reaction with the resin before modification and economical efficiency, α, β-unsaturated aliphatic dicarboxylic anhydride having 8 or less carbon atoms is preferable, and maleic anhydride is particularly preferable.

(4) The modified hydrocarbon resin may have one or more carboxyl groups and acid anhydride groups derived from these unsaturated carboxylic acids and unsaturated dicarboxylic anhydrides.

The acid value of the modified hydrocarbon resin is preferably 0.5 to 20 KOH mg / g, more preferably 0.7 to 17 KOH mg / g, and more preferably 1.0 to 15 KOH mg / g. . When the acid value is within the above range, the obtained hot melt adhesive composition can have a lower odor and a smaller change in hue due to thermal deterioration and the like. The acid value of the modified hydrocarbon resin can be measured, for example, according to JIS K0070.

The modified hydrocarbon resin used in the present invention is a resin obtained by hydrogenating the above-mentioned resin before modification, which is modified with an unsaturated carboxylic acid or an unsaturated dicarboxylic acid anhydride. May include unreacted unsaturated carboxylic acids and unsaturated dicarboxylic acids. In the modified hydrocarbon resin, the total content of unreacted unsaturated carboxylic acid and unreacted unsaturated dicarboxylic anhydride is preferably 3000 ppm by weight or less, more preferably 2000 ppm by weight or less. More preferably, it is 1000 ppm by weight or less. When the content is within the above range, the odor of the obtained hot melt adhesive composition can be further reduced.

Here, the total content of the unreacted unsaturated carboxylic acid and the unreacted unsaturated dicarboxylic anhydride means the unsaturated carboxylic acid and the unsaturated carboxylic acid used as the acid modifier when producing the modified hydrocarbon resin. Of the dicarboxylic anhydrides, the unsaturated carboxylic acids and unsaturated dicarboxylic anhydrides contained in the modified hydrocarbon resin in the free state without reacting with the resin obtained by hydrogenating the resin before modification are used. It is the total content.

The total content of unreacted unsaturated carboxylic acid and unreacted unsaturated dicarboxylic anhydride is determined by dissolving the modified hydrocarbon resin in a solvent such as toluene, mixing with water, and extracting the unsaturated water into water. It can be measured by quantifying the total content of the carboxylic acid and the unsaturated dicarboxylic acid by liquid chromatography.

The weight average molecular weight (Mw) of the modified hydrocarbon resin is preferably in the range of 1,000 to 5,000, more preferably in the range of 1,500 to 4,700, and particularly preferably 1,500. More preferably, it is in the range of 800 to 4,500. When the weight average molecular weight (Mw) is within the above range, excellent thermal stability can be obtained. Further, in the obtained hot melt adhesive composition, the compatibility with the thermoplastic elastomer can be improved. Since it is favorable, the open time is long and the adhesive strength and the ease of coating can be excellent.

The Z-average molecular weight (Mz) of the modified hydrocarbon resin is preferably in the range of 1,500 to 12,500, more preferably in the range of 2,500 to 11,000, and particularly preferably 3,500. Preferably, it is in the range of 500 to 10,000. When the Z-average molecular weight (Mz) is within the above range, excellent thermal stability can be obtained, and further, in the obtained hot melt adhesive composition, compatibility with the thermoplastic elastomer can be improved. Since it is favorable, the open time is long and the adhesive strength and the ease of coating can be excellent.

In the present invention, the weight average molecular weight (Mw) and the Z average molecular weight (Mz) of the modified hydrocarbon resin are determined as values in terms of polystyrene measured by high performance liquid chromatography.

The ratio (Mz / Mw) of the Z average molecular weight to the weight average molecular weight of the modified hydrocarbon resin is preferably in the range of 1.5 to 2.5, and more preferably in the range of 1.6 to 2.4. It is preferable that the ratio be within a range of 1.65 to 2.35. When the above ratio is within the above range, excellent thermal stability can be obtained, and further, in the obtained hot melt adhesive composition, the compatibility with the thermoplastic elastomer becomes good. , The open time is long, and the adhesive strength and coating ease are excellent.

ガード The Gardner color number of a 50% by mass toluene solution of the modified hydrocarbon resin is preferably 5 or less, more preferably 4 or less. If this value is too large, the hue is inferior. The Gardner color number can be measured by preparing a 50% by mass toluene solution of a modified hydrocarbon resin, and measuring the Gardner color number of the prepared solution according to JIS K0071-2.

The softening point of the modified hydrocarbon resin is preferably 30 ° C. or higher, more preferably in the range of 50 ° C. to 125 ° C., and more preferably in the range of 60 ° C. to 120 ° C. When the softening point is within the above range, excellent heat stability can be obtained, and further, in the obtained hot melt adhesive composition, the compatibility with the thermoplastic elastomer becomes good. Therefore, the open time is long and the adhesive strength and the ease of coating can be excellent. The softening point of the modified hydrocarbon resin can be measured by the ring and ball method defined by JIS K2531.

Examples of a method for producing a modified hydrocarbon resin include a hydrogenation step of hydrogenating a resin before modification and an acid reaction by reacting an unsaturated carboxylic acid or an unsaturated dicarboxylic anhydride with the resin obtained in the hydrogenation step. And a denaturing step.

In the hydrogenation step, hydrogenation of the resin before modification can be performed by bringing the resin before modification into contact with hydrogen in the presence of a hydrogenation catalyst.

Examples of the hydrogenation catalyst used include JP-A-58-43412, JP-A-60-26024, JP-A-64-24826, JP-A-1-138257, JP-A-7-41550, and the like. And a homogeneous catalyst or a heterogeneous catalyst may be used.

Examples of the homogeneous catalyst include, for example, a combination of cobalt acetate / triethylaluminum, nickel acetylacetonate / triisobutylaluminum, titanocene dichloride / n-butyllithium, zirconocene dichloride / sec-butyllithium, and tetrabutoxytitanate / dimethylmagnesium. A catalyst system comprising a combination of a transition metal compound and an alkali metal compound; a noble metal complex catalyst such as dichlorobis (triphenylphosphine) palladium, chlorohydridocarbonyltris (triphenylphosphine) ruthenium, and chlorotris (triphenylphosphine) rhodium; .

Examples of the heterogeneous catalyst include catalysts in which a hydrogenation catalyst metal such as Ni or Pd is supported on a carrier. Examples of the carrier include silica, alumina, silica alumina, diatomaceous earth, and the like. Among them, a Ni catalyst supported on silica is preferable.

The hydrogenation reaction may be carried out directly on the resin before modification, or may be carried out in an organic solvent by dissolving the resin before modification in an organic solvent. From the viewpoint of operability, it is preferable to carry out directly on the resin before modification. The organic solvent used for dissolving the unmodified resin is not particularly limited as long as it is inert to the catalyst.However, since the resulting hydrogenated product has excellent solubility, a hydrocarbon solvent is usually used. Used.

Examples of the hydrocarbon solvent include aromatic hydrocarbons such as benzene and toluene; aliphatic hydrocarbons such as n-pentane and hexane; alicyclic hydrocarbons such as cyclohexane and decalin; Among these, cyclic aromatic hydrocarbons and alicyclic hydrocarbons are preferred. These organic solvents can be used alone or in combination of two or more. In addition, you may use the solvent used for superposition | polymerization of the resin before a modification as an organic solvent.

方法 The method of contacting the unmodified resin with hydrogen in the presence of the hydrogenation catalyst is not particularly limited. For example, a pre-modified resin and a hydrogenation catalyst are allowed to coexist in an appropriately selected container, and the mixture is agitated as necessary, and a batch treatment method of contacting with hydrogen, or a hydrogenation catalyst is previously filled in a packed column. And a continuous treatment method in which the unmodified resin is brought into contact with hydrogen while flowing the resin before modification.

The hydrogenation reaction can be performed according to a conventional method. By appropriately adjusting the reaction conditions such as the type of the hydrogenation catalyst and the reaction temperature, the hydrogenation ratio of the resin before modification and the iodine value of the modified hydrocarbon resin can be adjusted.

と When a homogeneous catalyst is used as the hydrogenation catalyst, the rate of hydrogenation of the resin before modification can be increased. As a homogeneous catalyst, a ruthenium homogeneous catalyst is suitable. The reaction temperature is preferably in the range of 100 ° C to 200 ° C, more preferably in the range of 130 ° C to 195 ° C. When a heterogeneous catalyst is used as the hydrogenation catalyst, the rate of hydrogenation of the resin before modification can be suppressed. As the heterogeneous catalyst, a nickel heterogeneous catalyst is suitable. The reaction temperature is preferably in the range of 150 ° C to 300 ° C, more preferably in the range of 180 ° C to 260 ° C.

水素 The hydrogen pressure in the hydrogenation reaction is, in terms of absolute pressure, usually in the range of 0.01 MPa to 10 MPa, preferably in the range of 0.05 MPa to 6 MPa, and more preferably in the range of 0.1 MPa to 5 MPa. The amount of hydrogen may be generally not less than the theoretically necessary amount of hydrogen, but may be in the range of 1 to 20 times the theoretically necessary amount of hydrogen to obtain a resin having the desired iodine value. it can.

後 After completion of the hydrogenation reaction, if necessary, the hydrogenation catalyst is removed from the reaction solution by centrifugation or filtration. The centrifugation method and filtration method are not particularly limited as long as the used catalyst can be removed. Removal by filtration is preferred because it is simple and efficient. In the case of filtration, pressure filtration or suction filtration may be used, and from the viewpoint of efficiency, it is preferable to use a filter aid such as diatomaceous earth and perlite. If necessary, a catalyst deactivator such as water or alcohol can be used, or an adsorbent such as activated clay or alumina can be added.

In the modification step, the resin obtained by hydrogenating the resin before modification in the hydrogenation step is treated with an unsaturated carboxylic acid or an unsaturated dicarboxylic acid anhydride to form a carboxyl group or an acid anhydride group with water. In this step, the modified hydrocarbon resin used in the present invention is introduced into the resin obtained by the addition. That is, this is a step of obtaining a modified hydrocarbon resin by reacting the resin obtained in the hydrogenation step with an unsaturated carboxylic acid or an unsaturated dicarboxylic anhydride (acid modification reaction) to acid-modify the resin.

The amount of the unsaturated carboxylic acid and the unsaturated dicarboxylic anhydride used as the acid modifier in the acid modification reaction is preferably 0.01 to 100 parts by mass of the resin before modification in consideration of the hue of the obtained resin. To 10 parts by mass, more preferably 0.05 to 5 parts by mass. In addition, the unsaturated carboxylic acid and the unsaturated dicarboxylic anhydride used as the acid modifier may be used alone or in combination of two or more.

反応 The reaction temperature of the above-mentioned acid modification reaction can be usually in the range of 50 to 300 ° C. If the reaction temperature is too low, the reaction efficiency is poor, and the total content of unreacted unsaturated carboxylic acids and unreacted unsaturated dicarboxylic anhydrides in the modified hydrocarbon resin may increase. In addition, the reaction time can usually be set within a range of 5 minutes to 20 hours. If the reaction time is too short, the reaction efficiency is poor, and the total content of unreacted unsaturated carboxylic acid and unreacted unsaturated dicarboxylic anhydride in the modified hydrocarbon resin may increase. Further, in the acid modification reaction, a diluent, an anti-gelling agent, a reaction accelerator and the like may be present as necessary.

The modified hydrocarbon resin has an iodine value, a weight average molecular weight (Mw), a Z average molecular weight (Mz), a ratio of the Z average molecular weight to the weight average molecular weight (Mz / Mw), a Gardner color number, a softening point, an acid value, and The total content of unreacted unsaturated carboxylic acid and unreacted unsaturated dicarboxylic anhydride is easily adjusted to a desired range by preparing a modified hydrocarbon resin in accordance with the above-described blending and production method. can do.

<Thermoplastic elastomer>
The hot melt adhesive composition of the present invention contains a thermoplastic elastomer in addition to the above-mentioned modified hydrocarbon resin. Although it is not particularly limited as the thermoplastic elastomer, the thermoplastic elastomer used as the base polymer of the hot melt adhesive can be used without limitation, but from the viewpoint that the function and effect of the present invention can be further enhanced, At least one selected from an ethylene-vinyl acetate copolymer, a styrene-based thermoplastic elastomer, and a polyolefin-based thermoplastic elastomer is preferable.

The ethylene-vinyl acetate copolymer is not particularly limited, but preferably has a vinyl acetate monomer unit content of 10 to 50% by mass, more preferably 15 to 40% by mass. More preferably, the content is in the range of 15 to 35% by mass. As the ethylene-vinyl acetate copolymer, those having a melt flow rate of 1 to 500 g / 10 minutes can be preferably used.

The ethylene-vinyl acetate copolymer is available as a commercial product. For example, "EVAFLEX @ EV220 (trade name)" manufactured by DuPont-Mitsui Polychemicals and "VA900 (trade name)" manufactured by Lotte Chemical Co., Ltd. And the like can be suitably used.

The styrene-based thermoplastic elastomer is not particularly limited, and may be a random, block, graft, or other copolymer of a styrene-based monomer and another monomer copolymerizable with the styrene-based monomer, and such a copolymer. Examples include a coalesced hydrogenated product, and a block copolymer including at least one aromatic vinyl polymer block and at least one conjugated diene polymer block. Specific examples of such a block copolymer include styrene-isoprene-block copolymer, styrene-isoprene-styrene-triblock copolymer, isoprene-styrene-isoprene-triblock copolymer, styrene-isoprene-styrene- An isoprene tetrablock copolymer and a mixture thereof can be suitably used.

ポリ Also, the polyolefin-based thermoplastic elastomer is not particularly limited, and examples thereof include an ethylene / α-olefin copolymer. In order to obtain an ethylene / α-olefin copolymer, the α-olefin copolymerized with ethylene is not particularly limited. For example, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 4-methyl Α-olefins having 3 to 20 carbon atoms, such as -1-pentene and 1-octene, are preferred, α-olefins having 6 to 8 carbon atoms are more preferred, and 1-octene is even more preferred. The α-olefin may be used alone or in combination of two or more.

The content ratio of the α-olefin unit in the ethylene / α-olefin copolymer is not particularly limited, but the ratio of the α-olefin unit to all the monomer units is preferably 20 to 40 mol%. . As the ethylene / α-olefin copolymer, those having a melt flow rate of 200 to 1500 g / 10 minutes can be preferably used.

The mixing ratio of the thermoplastic elastomer and the modified hydrocarbon resin in the hot melt adhesive composition of the present invention is not particularly limited, but the modified hydrocarbon resin is preferably 50 to 50 parts by mass based on 100 parts by mass of the thermoplastic elastomer. 500 parts by mass are preferable, and 80 to 400 parts by mass are more preferable. When the blending ratio of the modified hydrocarbon resin is in this range, the adhesive strength of the hot melt adhesive composition of the present invention becomes particularly good.

ホット The hot melt adhesive composition of the present invention may be composed of only the modified hydrocarbon resin and the thermoplastic elastomer, but may further contain other components. Other components that can be included in the hot melt adhesive composition of the present invention include waxes, softeners, antioxidants, tackifying resins other than the modified hydrocarbon resins of the present invention, and polymers other than those described above. Other compounding agents such as heat stabilizers, ultraviolet absorbers, and fillers can be added. The hot melt adhesive composition of the present invention is preferably a solvent-free composition containing no solvent.

The wax that can be blended in the hot melt adhesive composition of the present invention is not particularly limited, and examples thereof include polyethylene wax, polyethylene oxide wax, paraffin wax, microcrystalline wax, Fischer-Tropsh wax, oxidized Fischer-Tropsh wax, Hydrogenated castor oil wax, polypropylene wax, by-product polyethylene wax, stearamide hydroxide wax and the like can be used. One type of wax may be used alone, or two or more types may be used in combination. The content of the wax in the hot melt adhesive composition is not particularly limited, but is preferably from 10 to 200 parts by mass, more preferably from 20 to 100 parts by mass, per 100 parts by mass of the thermoplastic elastomer. . When the content of the wax is within this range, the obtained hot melt adhesive composition has particularly excellent coating applicability.

The antioxidant that can be added to the hot melt adhesive composition of the present invention is not particularly limited. For example, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate ], Octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,6-di-t-butyl-p-cresol, di-t-butyl-4-methylphenol, etc. Hindered phenol compounds; thiodicarboxylate esters such as dilauryl thiopropionate; and phosphites such as tris (nonylphenyl) phosphite can be used. The amount of the antioxidant is not particularly limited, but is usually 10 parts by mass or less, preferably 0.5 to 5 parts by mass, per 100 parts by mass of the thermoplastic elastomer. The antioxidants may be used alone or in a combination of two or more.

The softening agent that can be blended in the hot melt adhesive composition of the present invention is not particularly limited, and examples thereof include aromatic, paraffinic or naphthenic process oils; liquid polymers such as polybutene and polyisobutylene; Can be used. One type of softener may be used alone, or two or more types may be used in combination.

従来 As the tackifying resin other than the above-mentioned modified hydrocarbon resin that can be added to the hot melt adhesive composition of the present invention, a conventionally known tackifying resin can be used. Specifically, rosin; modified rosins such as disproportionated rosin and dimerized rosin; esterified products of polyhydric alcohols such as glycol, glycerin and pentaerythritol with rosin or modified rosins; terpene resins; , Aromatic, alicyclic or aliphatic-aromatic copolymer-based hydrocarbon resins or hydrides thereof; phenol resins; coumarone-indene resins; One of these tackifier resins may be used alone, or two or more thereof may be used in combination.

In obtaining the hot melt adhesive composition of the present invention, the method of mixing the above-described modified hydrocarbon resin, thermoplastic elastomer, and other components that are added as needed is not particularly limited, for example, After dissolving each component in a solvent and mixing uniformly, a method of removing the solvent by heating or the like, a method of melting and mixing each component by a kneader or the like can be used. From the viewpoint of more efficient mixing, melt mixing is preferred among these methods. The temperature at which the melt mixing is performed is not particularly limited, but is usually in the range of 100 to 200 ° C.

The hot melt adhesive composition of the present invention contains the above-mentioned modified hydrocarbon resin as a tackifying resin, so that the adhesive performance is high, the hue and the heat resistance hue stability are excellent, and the odor is reduced. (For example, odor is reduced even when heated at a relatively high temperature of 160 ° C.). Therefore, the hot-melt adhesive composition of the present invention can be applied to bonding of various members by utilizing such properties, and furthermore, is an energy-saving, highly productive, and highly adhesive bond. Is what you can do. The hot melt adhesive composition of the present invention is suitably used, for example, as an adhesive for various kinds of adhesive tapes and labels. Specifically, by forming a pressure-sensitive adhesive layer comprising the hot-melt adhesive composition of the present invention on a sheet-like substrate constituting a pressure-sensitive adhesive tape or label, the base material and the hot-melt adhesive of the present invention are formed. It is suitably used as a pressure-sensitive adhesive tape or label comprising a pressure-sensitive adhesive layer comprising a melt-adhesive composition.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to only these Examples. “Parts” and “%” are based on mass unless otherwise specified.
The test methods performed in this example and comparative examples are as follows.

(1) Weight average molecular weight, Z average molecular weight, and molecular weight distribution of the modified hydrocarbon resin The modified hydrocarbon resin was analyzed by gel permeation chromatography, and the weight average molecular weight (Mw) and the Z average molecular weight (Mw) in terms of standard polystyrene were obtained. Mz) was determined, and the molecular weight distribution was shown by the ratio of Mz / Mw. In the gel permeation chromatography analysis, "HLC-8320GPC" manufactured by Tosoh Corporation was used as a measuring apparatus, and a column in which three "TSKgel SuperMultipore HZ" manufactured by Tosoh Corporation were connected was used, and tetrahydrofuran was used as a solvent. , 40 ° C., and a flow rate of 1.0 mL / min.

(2) Iodine value of modified hydrocarbon resin The iodine value of the modified hydrocarbon resin was measured according to JIS K0070.

(3) Acid value of modified hydrocarbon resin The acid value of the modified hydrocarbon resin was measured according to JIS K0070.

(4) Softening point of modified hydrocarbon resin (° C)
The softening point (° C.) of the modified hydrocarbon resin was measured by the ring and ball method specified by JIS K2531.

(5) Solution hue of modified hydrocarbon resin (Gardner color number)
A 50% by mass toluene solution of the modified hydrocarbon resin was prepared, and the Gardner color number of the solution was measured according to JIS K0071-2. The smaller the value, the better the hue.

(6) Heat-resistant hue of modified hydrocarbon resin (Gardner color number)
The modified hydrocarbon resin was allowed to stand in an oven at 200 ° C. for 3 hours, and then allowed to cool, and then the Gardner color number was measured according to JIS K0071-2. As the numerical value is smaller, it can be determined that the modified hydrocarbon resin is excellent in heat-resistant hue stability, and accordingly, the hot-melt adhesive composition obtained using such a modified hydrocarbon resin also has heat-resistant hue stability. Can be determined to be excellent.

(7) Content of Unreacted Maleic Anhydride in Modified Hydrocarbon Resin The modified hydrocarbon resin was dissolved in toluene, extracted as maleic acid with water, and the aqueous phase was measured by ion chromatography.

(8) Cloud point (° C.) of hot melt adhesive composition
The hot melt adhesive composition was placed in a test tube, a thermometer was inserted to the bottom, and then heated and melted to 180 ° C. Thereafter, the mixture was allowed to cool, and the temperature at which the bottom of the test tube became cloudy was recorded as the cloud point. The lower the value, the better the compatibility between the components constituting the hot melt adhesive composition, and as a result, the hot melt adhesive composition has a longer open time and higher adhesive strength. Become.

(9) Hue of Hot Melt Adhesive Composition The hue of the hot melt adhesive composition was visually confirmed.

(10) Peeling adhesive strength of hot melt adhesive composition (N / 25 mm)
The hot-melt adhesive composition is melted at 180 ° C. and applied on an aluminum substrate at a thickness of 30 μm to form an adhesive layer composed of the hot-melt adhesive composition. A sample was prepared. Then, the peel adhesion of the obtained sample was measured at 23 ° C. according to PSTC-1 (180 ° peel adhesion test by Adhesive Tapes Committee (US)). The higher the value of the peel adhesive force, the better the adhesive performance.

(11) Odor evaluation test The sensory test of the hot melt adhesive composition was carried out according to the Odor Measurement Method-5 in the Odor Measurement Method published by the Association of Odor and Odor Environment.
Specifically, first, 10 g of a hot-melt adhesive composition having a size of about 10 mm × 5 mm × 5 mm was placed in a 120 mL heat-resistant container and capped with aluminum foil. Then, the heat-resistant container containing the hot melt adhesive composition was placed in an oven and heated at a temperature of 160 ° C. for 30 minutes, and the odor after heating was confirmed.
The odor was confirmed by a panel of six persons who were not accustomed to the odor of petroleum resin (ie, did not touch the odor of petroleum resin in everyday life). In this test, in order to prevent olfactory fatigue, a method of dividing a panel of six persons into two groups of three persons and smelling the odor by one group was adopted. The order of the samples that smell the odor was randomized.
0: Odorless 1: Smell finally perceivable (detection threshold density)
2: Weak smell to understand what smell is (cognitive threshold concentration)
3: Smell that can be easily perceived 4: Strong smell 5: Intense smell The results of the sensory test are as follows. It was determined by averaging. The smaller the value of the sensory test, the better.

[Example 1]
1. Preparation of Modified Hydrocarbon Resin A mixture of 34.5 parts of cyclopentane and 26.7 parts of cyclopentene was charged into a polymerization reactor, heated to 60 ° C., and then 0.7 part of aluminum chloride was added (mixture). M1). Subsequently, 42.7 parts of 1,3-pentadiene, 6.8 parts of isobutylene, 21.3 parts of styrene, 0.6 part of C4-C6 unsaturated hydrocarbon, 0.1 part of dicyclopentadiene, and C4-C6 saturated carbon A polymerization reaction containing the mixture M1 was conducted by maintaining a mixture (a1) consisting of 8.2 parts of hydrogen and 0.5 part of t-butyl chloride through separate lines at a temperature (80 ° C.) for 60 minutes. Polymerization was carried out while continuously adding to the vessel. Thereafter, an aqueous sodium hydroxide solution was added to the polymerization reactor to stop the polymerization reaction. Table 1 shows the types and amounts of the components in the polymerization reactor during the polymerization reaction. The precipitate generated by stopping the polymerization was removed by filtration to obtain a polymer solution containing a resin before modification, an unreacted monomer, and the like.
In addition, a part of the polymer solution was taken out, charged in a distillation still and heated under a nitrogen atmosphere to remove the polymerization solvent and unreacted monomers to obtain a resin before modification.

Further, a polymer solution was supplied as a raw material to a multitubular heat exchange hydrogenation reactor, and the resin before modification was hydrogenated. The hydrogenation reaction uses a nickel silica catalyst (manufactured by Nikki Shokubai Kasei Co., Ltd., N108F) as a hydrogenation catalyst, a hydrogen pressure of 2 MPa, a reaction temperature of 200 ° C., and a residence time of 30 minutes in a reaction tube. Two parts for 100 parts of resin.

(4) A polymer solution containing a resin in which a resin before modification was hydrogenated was charged into a distillation still and heated under a nitrogen atmosphere to remove a polymerization solvent and unreacted monomers. Subsequently, at 200 ° C. or higher, low-molecular-weight oligomer components were distilled off while blowing saturated steam.

Next, 1.8 parts of maleic anhydride was added to 100 parts of the molten resin, and an addition reaction was performed at 230 ° C. for 1 hour. Thereafter, the molten resin was taken out of the distillation still and allowed to cool to room temperature to obtain the modified hydrocarbon resin of Example 1.

For the obtained modified hydrocarbon resin of Example 1, the weight average molecular weight, Z average molecular weight, molecular weight distribution, iodine value, acid value, softening point, solution hue (Gardner color number), heat resistant hue (Gardner color number) and The amount of the maleic anhydride was measured. Table 1 shows the results.

2. Preparation of hot melt adhesive composition 50 parts of modified hydrocarbon resin obtained above, 40 parts of ethylene-vinyl acetate copolymer resin (trade name: EVAFLEX EV220, manufactured by DuPont-Mitsui Polychemicals), paraffin wax (Melting point: 63 ° C.) 10 parts and an antioxidant (Irganox 1010 (trade name) manufactured by BASF) 1.25 parts were kneaded at 180 ° C. for 1 hour, and the hot melt adhesive of Example 1 was kneaded. Agent composition was obtained. About the obtained hot-melt adhesive composition, the cloud point, the hue, and the peel adhesive strength were measured, and the odor evaluation test was performed. Table 1 shows the results.

[Examples 2 to 4]
The modified hydrocarbons of Examples 2 to 4 were prepared in the same manner as in Example 1 except that the types and amounts of the components added to the polymerization reactor, and the polymerization temperature and the hydrogenation conditions were changed as shown in Table 1. Resins were obtained respectively. Incidentally, diisobutylene and cyclopentadiene not described in Example 1 were mixed with t-butyl chloride together with 1,3-pentadiene and the like, and subjected to polymerization. In Example 4, benzyl chloride was used in place of t-butyl chloride, and 1,3-pentadiene and the like were mixed with benzyl chloride in place of t-butyl chloride and subjected to polymerization. The modified hydrocarbon resins obtained in Examples 2 to 4 were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Then, the hot melt adhesive compositions of Examples 2 to 4 were obtained in the same manner as in Example 1 except that the modified hydrocarbon resins of Examples 2 to 4 obtained above were used. Similarly, measurement and evaluation were performed. Table 1 shows the results.

[Example 5]
Instead of using 40 parts of the ethylene-vinyl acetate copolymer resin, 45.5 parts of a styrene-isoprene-styrene copolymer (manufactured by Zeon Corporation, trade name: Quintac 3620) was used, and the amount of the modified hydrocarbon resin used was reduced. From 50 parts to 45.5 parts, paraffin wax was changed to naphthenic oil, the amount used was changed from 10 parts to 9 parts, and the amount of antioxidant used was changed from 1.25 parts to 1.5 parts, respectively. Except for the change, the hot melt adhesive composition of Example 5 was obtained in the same manner as in Example 1, and the measurement and evaluation were performed in the same manner. Table 1 shows the results.

[Example 6]
Instead of using 40 parts of the ethylene-vinyl acetate copolymer resin, 40 parts of an ethylene / α-olefin copolymer (manufactured by Dow Chemical Company, trade name: Affinity GA1950) was used, and the amount of the modified hydrocarbon resin used was changed to 50 parts. To 40 parts, the amount of paraffin wax used was changed from 10 parts to 20 parts, and the used amount of antioxidant was changed from 1.25 parts to 1.5 parts. A hot melt adhesive composition of Example 6 was obtained and measured and evaluated in the same manner. Table 1 shows the results.

[Comparative Example 1]
Same as Example 1 except that the type and amount of the components added to the polymerization reactor and the polymerization temperature were changed as shown in Table 1, and that the hydrogenation reaction and the acid modification with maleic anhydride were not performed. Thus, the hydrocarbon resin of Comparative Example 1 was obtained. Note that cyclopentadiene not described in Example 1 was mixed with 1,3-pentadiene and the like and used for polymerization. The obtained modified hydrocarbon resin of Comparative Example 1 was measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Then, a hot melt adhesive composition of Comparative Example 1 was obtained and measured in the same manner as in Example 1 except that the modified hydrocarbon resin of Comparative Example 1 obtained above was used. , Was evaluated. Table 1 shows the results.

[Comparative Example 2]
Comparative Example 2 was repeated in the same manner as in Example 1 except that the type and amount of the components added to the polymerization reactor and the polymerization temperature were changed as shown in Table 1, and that no hydrogenation reaction was performed. A hydrocarbon resin was obtained. Incidentally, diisobutylene and cyclopentadiene not described in Example 1 were mixed with t-butyl chloride together with 1,3-pentadiene and the like, and subjected to polymerization. The obtained modified hydrocarbon resin of Comparative Example 2 was measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Then, a hot melt adhesive composition of Comparative Example 2 was obtained and measured in the same manner as in Example 1 except that the modified hydrocarbon resin of Comparative Example 2 obtained above was used. , Was evaluated. Table 1 shows the results.

[Comparative Example 3]
Same as Example 1 except that the kind and amount of the components added to the polymerization reactor, and the polymerization temperature and the hydrogenation conditions were changed as shown in Table 1, and the acid modification with maleic anhydride was not performed. Thus, a hydrocarbon resin of Comparative Example 3 was obtained. Note that cyclopentadiene not described in Example 1 was mixed with 1,3-pentadiene and the like and used for polymerization. The obtained modified hydrocarbon resin of Comparative Example 3 was measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Then, a hot melt adhesive composition of Comparative Example 3 was obtained and measured in the same manner as in Example 1 except that the modified hydrocarbon resin of Comparative Example 3 obtained above was used. , Was evaluated. Table 1 shows the results.

[Comparative Example 4]
A hydrocarbon resin of Comparative Example 4 was obtained in the same manner as in Example 1, except that the type and amount of components added to the polymerization reactor, and the polymerization temperature and the hydrogenation conditions were changed as shown in Table 1. . Note that xylene not described in Example 1 was mixed with cyclopentane and the like. The modified hydrocarbon resin of Comparative Example 4 was measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Then, a hot melt adhesive composition of Comparative Example 4 was obtained and measured in the same manner as in Example 1 except that the modified hydrocarbon resin of Comparative Example 4 obtained above was used. , Was evaluated. Table 1 shows the results.

As shown in Table 1, the resin was hydrogenated hydrocarbon resin having a specific composition obtained by further acid-modified, and modified hydrocarbon resins iodine value is in the range of 45 ~ 125gI 2 _/ 100g, According to the hot melt adhesive composition containing the thermoplastic elastomer, the adhesive performance was high, the hue and heat resistance hue stability were excellent, and the odor was suppressed even at a high temperature of 160 ° C. (Examples 1 to 6).

On the other hand, when the iodine value exceeds 125gI 2 _/ 100g is, results in odor becomes strong and, if you did not acid modified further was poor in adhesive performance (Comparative Example 1 , 2).
Further, even if the iodine value is in the range of 45 _~ 125gI 2 / 100g, if you did not acid modified, was inferior in adhesive performance and hue (Comparative Example 3).
Further, when the iodine value is less than 45I _2/100 g, together with the poor adhesive performance and hue, resulted in odor becomes stronger (Comparative Example 4).

Claims

A hot melt adhesive composition containing a modified hydrocarbon resin and a thermoplastic elastomer,
The modified hydrocarbon resin,
20 to 70% by mass of 1,3-pentadiene monomer unit,
An alicyclic monoolefin monomer unit having 4 to 6 carbon atoms, 10 to 50% by mass,
An acyclic monoolefin monomer unit having 4 to 8 carbon atoms, 5 to 40% by mass,
An unsaturated carboxylic acid or unsaturated resin is added to a resin obtained by hydrogenating a hydrocarbon resin containing 0 to 1% by mass of an alicyclic diolefin monomer unit and 0 to 40% by mass of an aromatic monoolefin monomer unit. A carboxyl group or an acid anhydride group derived from a dicarboxylic acid anhydride is introduced,
The modified hot melt adhesive composition iodine value of the hydrocarbon resin is in the range of 45 ~ 125gI 2 / 100g.
The modified hydrocarbon resin,
The weight average molecular weight (Mw) is in the range of 1,000 to 5,000,
Z average molecular weight (Mz) is in the range of 1,500 to 12,500,
The ratio of the Z average molecular weight to the weight average molecular weight (Mz / Mw) is in the range of 1.5 to 2.5,
The 50% by mass toluene solution has a Gardner color number of 5 or less,
2. The hot-melt adhesive composition according to claim 1, which has a softening point of 30 ° C. or higher and an acid value of 0.5 to 20 KOH mg / g.
3. The hot melt adhesive composition according to claim 1, wherein the unsaturated dicarboxylic anhydride is maleic anhydride.
4. The method according to claim 1, wherein the total content of the unreacted unsaturated carboxylic acid and the unreacted unsaturated dicarboxylic anhydride in the modified hydrocarbon resin is 3,000 ppm by weight or less. Hot melt adhesive composition.
The hot melt adhesive according to any one of claims 1 to 4, wherein the thermoplastic elastomer is at least one selected from an ethylene-vinyl acetate copolymer, a styrene-based thermoplastic elastomer, and a polyolefin-based thermoplastic elastomer. Adhesive composition.