JP2018135468A - Hot-melt adhesive resin film, hot-melt adhesive resin laminate and laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot-melt adhesive resin film which exhibits sufficient adhesiveness particularly when bonded to metal and can maintain high adhesiveness, a hot-melt adhesive resin laminate, and a laminate using them.SOLUTION: A hot melt adhesive resin film contains an acid-modified polyolefin resin and a crosslinkable resin, where a content of the crosslinkable resin is 1 mass% or more and 20 mass% or less with respect to the total amount of the acid-modified polyolefin resin and the crosslinkable resin, and a peeling strength when a peeling test is performed on the following condition is 0.5 N/mm or more. Test condition: the laminate is immersed in pure water of 95°C for 500 hours, and then a peeling strength is measured when either an aluminum plate or a stainless plate of the laminate is fixed in water at 95°C, and the other is stretched at a stretching strength of 300 mm/min.SELECTED DRAWING: None

Description

  The present invention relates to a hot-melt adhesive resin film, a hot-melt adhesive resin laminate, and a laminate.

  Conventionally, as an adhesive film that adheres to an adherend, a thermosetting epoxy adhesive layer is formed on both surfaces of a base material made of a heat-resistant resin film as described in Patent Document 3 3 A laminated film having a layer structure is known.

JP 2013-28738 A

  Conventional adhesive films have not had sufficient adhesive strength, particularly when bonded to metal. For this reason, there existed a subject that adhesiveness could not fully be maintained after severe endurance conditions.

  The present invention has been made in view of the above circumstances, and particularly when hot-melt adhesive resin film capable of exhibiting sufficient adhesiveness and maintaining high adhesiveness when bonded to a metal, hot-melt It is an object of the present invention to provide an adhesive resin laminate and a laminate using these.

That is, the present invention employs the following configuration.
[1] An acid-modified polyolefin resin and a crosslinkable resin are contained, and the content of the crosslinkable resin is 1% by mass or more and 20% by mass or less based on the total amount of the acid-modified polyolefin resin and the crosslinkable resin. A hot melt adhesive resin film having a peel strength of 0.5 N / mm or more when a peel test is performed under the following conditions.
(Peeling test conditions)
Test piece: A laminate in which an aluminum plate and a stainless steel plate are heat-bonded with a hot-melt adhesive resin film. The shapes of the aluminum plate and the stainless plate are 10 mm width, 50 mm length, and 30 μm thickness, respectively. The shape of the hot melt adhesive resin film is 10 mm × 10 mm.
Test conditions: The laminate is immersed in pure water at 95 ° C. for 500 hours. Thereafter, either the aluminum plate or the stainless steel plate of the laminate is fixed in 95 ° C. water, and the peel strength when the other is pulled at a pulling speed of 300 mm / min is measured.
[2] Further containing an elastomer resin, the content of the elastomer resin is 1% by mass or more and 20% by mass or less based on the total amount of the acid-modified polyolefin resin, the crosslinkable resin, and the elastomer resin. 1] The hot-melt-adhesive resin film according to [1].
[3] The hot melt adhesive resin film according to [2], wherein the elastomer resin is an olefin resin.
[4] Any one of [1] to [3], wherein the crosslinkable resin is at least one selected from the group consisting of a phenol novolac-modified epoxy resin, an oxazoline group-containing styrene resin, or an epoxy group-containing polyolefin resin. The hot-melt-adhesive resin film as described in one.
[5] A first surface layer, a first intermediate layer made of a polyolefin resin, a base material layer, a second intermediate layer made of a polyolefin resin, and a second surface layer are laminated in this order, At least one of the surface layer 1 and the second surface layer is a hot melt adhesive resin laminate comprising the hot melt adhesive resin film according to any one of [1] to [4]. And
A hot melt adhesive resin laminate having a peel strength of 0.5 N / mm or more when a peel test is performed under the following conditions.
(Peeling test conditions)
Test piece: A laminate in which an aluminum plate and a stainless steel plate are heated and bonded with a hot-melt adhesive resin laminate. The shapes of the aluminum plate and the stainless plate are 10 mm width, 50 mm length, and 30 μm thickness, respectively. The shape of the hot melt adhesive resin laminate is 10 mm × 10 mm.
Test conditions: The laminate is immersed in pure water at 95 ° C. for 500 hours. Thereafter, either the aluminum plate or the stainless steel plate of the laminate is fixed in 95 ° C. water, and the peel strength when the other is pulled at a pulling speed of 300 mm / min is measured.
[6] The hot melt adhesive resin laminate according to [5], wherein the film thicknesses of the first intermediate layer and the second intermediate layer are 1 μm or more and 5 μm or less, respectively.
[7] The hot melt adhesive resin laminate according to [5] or [6], wherein the first intermediate layer and the second intermediate layer are composed of a modified polyolefin resin and a compound containing an epoxy group.
[8] The hot melt adhesive resin laminate according to any one of [5] to [7], wherein the first intermediate layer and the second intermediate layer are composed of a modified polyolefin resin and an isocyanate compound. .
[9] Of the above [5] to [8], wherein the substrate layer is composed of one or more selected from the group consisting of polyethylene naphthalate, cycloolefin polymer, cycloolefin copolymer, methylpentene polymer, acrylic resin, and polycarbonate. The hot-melt-adhesive resin laminated body as described in any one.
[10] A laminate comprising the hot melt adhesive resin film according to any one of [1] to [4] and an adherend.
[11] A laminate comprising the hot-melt adhesive resin laminate according to any one of [5] to [9] and an adherend.

  According to the present invention, a hot-melt-adhesive resin film, a hot-melt-adhesive resin laminate, and a hot-melt-adhesive resin laminate capable of exhibiting sufficient adhesiveness and maintaining high adhesiveness, particularly when bonded to a metal, and these are used. A laminated body can be provided.

It is sectional drawing which shows schematic structure of 1st Embodiment of the hot-melt-adhesive resin film of this invention. It is sectional drawing which shows schematic structure of 2nd Embodiment of the hot-melt-adhesive resin film of this invention. It is a schematic diagram of the apparatus used for a peeling test. It is a schematic diagram explaining the lamination | stacking state of the test piece used for a peeling test.

<Hot melt adhesive resin film>
<< First Embodiment >>
The hot melt adhesive resin film of this embodiment contains an acid-modified polyolefin resin and a crosslinkable resin, and the content of the crosslinkable resin is based on the total amount of the acid-modified polyolefin resin and the crosslinkable resin. It is 1 mass% or more and 20 mass% or less, and the peeling strength when a peeling test is done on the following conditions is 0.5 N / mm or more.
(Peeling test conditions)
Test piece: A laminate in which an aluminum plate and a stainless steel plate are heat-bonded with a hot-melt adhesive resin film. The shapes of the aluminum plate and the stainless plate are 10 mm width, 50 mm length, and 30 μm thickness, respectively. The shape of the hot melt adhesive resin film is 10 mm × 10 mm.
Test conditions: The laminate is immersed in pure water at 95 ° C. for 500 hours. Thereafter, either the aluminum plate or the stainless steel plate of the laminate is fixed in 95 ° C. water, and the peel strength when the other is pulled at a pulling speed of 300 mm / min is measured.
Hereinafter, the present invention will be described based on preferred embodiments.

  The hot melt adhesive resin film of the present invention exhibits excellent adhesion to various adherends, particularly metals. Furthermore, the hot-melt adhesive resin film of the present invention can maintain high adhesion particularly to metals. Moreover, the hot melt adhesive film of the present invention can maintain high adhesiveness even when used in a high temperature and high humidity environment.

  A hot-melt adhesive resin film 1 according to this embodiment shown in FIG. 1 is a single-layer film and contains an acid-modified polyolefin resin and a crosslinkable resin. Each resin component will be described below.

Acid-modified polyolefin resin Acid-modified polyolefin resin (hereinafter referred to as “component (A)”) is a polyolefin-based resin modified with an unsaturated carboxylic acid or a derivative thereof, and includes a carboxy group in the polyolefin-based resin. And an acid functional group such as a carboxylic anhydride group.
The component (A) can be obtained by modifying a polyolefin resin with an unsaturated carboxylic acid or a derivative thereof, or copolymerizing an acid functional group-containing monomer and an olefin. Especially, as (A) component, what was obtained by acid-modifying polyolefin resin is preferable.
Examples of the acid modification method include graft modification in which a polyolefin resin and an acid functional group-containing monomer are melt-kneaded in the presence of a radical polymerization initiator such as an organic peroxide or an aliphatic azo compound.

Examples of the polyolefin resin include polyethylene, polypropylene, poly-1-butene, polyisobutylene, a random copolymer of propylene and ethylene or α-olefin, and a block copolymer of propylene and ethylene or α-olefin. It is done. Among these, homopolypropylene (propylene homopolymer; hereinafter sometimes referred to as “homo PP”), propylene-ethylene block copolymer (hereinafter sometimes referred to as “block PP”), propylene-ethylene. Polypropylene resins such as random copolymers (hereinafter sometimes referred to as “random PP”) are preferred, and random PP is particularly preferred.
Examples of the olefins for copolymerization include olefinic monomers such as ethylene, propylene, 1-butene, isobutylene, 1-hexene, and α-olefin.

The acid functional group-containing monomer is a compound having an ethylenic double bond and a carboxy group or a carboxylic anhydride group in the same molecule, and various unsaturated monocarboxylic acids, dicarboxylic acids, or dicarboxylic acid acids. Anhydrides are mentioned.
Acid functional group-containing monomers having carboxy groups (carboxy group-containing monomers) include acrylic acid, methacrylic acid, maleic acid, nadic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, tetrahydrophthalic acid, endo -Α, β-unsaturated carboxylic acid monomers such as bicyclo [2.2.1] -5-heptene-2,3-dicarboxylic acid (endic acid).
Examples of acid functional group-containing monomers having carboxylic anhydride groups (carboxylic anhydride group-containing monomers) include unsaturated dicarboxylic acids such as maleic anhydride, nadic anhydride, itaconic anhydride, citraconic anhydride, and endic anhydride An anhydride monomer is mentioned.
These acid functional group-containing monomers may be used alone or in combination of two or more in the component (A).

Among them, the acid functional group-containing monomer is preferably an acid functional group-containing monomer having an acid anhydride group because of its high reactivity with the component (B) described below, more preferably a carboxylic acid anhydride group-containing monomer. Maleic acid is particularly preferred.
When a part of the acid functional group-containing monomer used for acid modification is unreacted, the unreacted acid functional group-containing monomer was removed in advance in order to prevent a decrease in adhesive strength due to the unreacted acid functional group-containing monomer. It is preferable to use those as the component (A). Here, “unreacted” means not used for acid modification.

  Among these, as the component (A), maleic anhydride-modified polypropylene is preferable from the viewpoint of exhibiting high adhesion to metal.

Crosslinkable resin The crosslinkable resin (hereinafter referred to as “component (B)”) is particularly a resin that can form a crosslinked structure with the component (A) and can exhibit adhesion to an adherend. It is not limited. In this embodiment, it is preferable that it is 1 or more types selected from the group which consists of a phenol novolak modified epoxy resin, an oxazoline group containing styrene resin, or an epoxy group containing polyolefin resin.

.. Phenol novolac modified epoxy resin The phenol novolac modified epoxy resin (hereinafter referred to as “component (B1)”) as the component (B) is a resin that is solid at room temperature (23 ° C.). When the component (A) and the component (B1) are polymerized by melt kneading by using the component (B1) that is solid at normal temperature, melt kneading is performed in accordance with the melting temperature of the component (A). And the characteristics of the component (B1) are less likely to be impaired.

  The component (B1) is a polymer compound having a phenol novolac resin obtained by acid condensation of phenol and formaldehyde as a basic structure, and an epoxy group introduced into a part of the structure. The amount of epoxy group introduced per molecule in the phenol novolac type epoxy resin is not particularly limited. In the present embodiment, by reacting an epoxy group raw material such as epichlorohydrin with a phenol novolac resin, a large number of epoxy groups can be introduced into a large number of phenolic hydroxyl groups present in the phenol novolac resin. Thereby, a polyfunctional epoxy resin can be obtained.

Among these, as the component (B1), a resin having a phenol novolac structure as a basic skeleton and also having a bisphenol A structure is preferable. In addition, the bisphenol A structure in (B1) component should just be a structure which can be induced | guided | derived from bisphenol A, and the both-ends hydroxyl group of bisphenol A may be substituted by groups, such as an epoxy group containing group.
An example of the component (B1) is a resin represented by the following general formula (1).

［式（１）中、Ｒ^１〜Ｒ^６はそれぞれ独立に水素原子またはメチル基であり、ｎは０〜１０の整数であり、Ｒ^Ｘはエポキシ基を有する基である。］

In Expression ^(1), R 1 ~R ⁶ are each independently a hydrogen atom or a methyl group, n is an integer of 0, ^{R X} is a group having an epoxy group. ]

In the general formula (1), R ^{1 to} R ⁶ are each independently a hydrogen atom or a methyl group. When n is an integer of 2 or more, R ³ and R ⁴ may be the same or different.
The resin represented by the general formula (1) preferably satisfies at least one of the following (i) to (iii).
(I) R ¹ and R ² are both methyl groups;
(Ii) both R ³ and R ⁴ are methyl groups;
(Iii) R ⁵ and R ⁶ are both methyl groups;
For example, by satisfying the above (i), a structure in which the carbon atom to which R ¹ and R ² are bonded and the ^two hydroxyphenyl groups to which the carbon atom is bonded is derived from bisphenol A in the general formula (1). Will be constructed.

In the general formula (1), R ^X is a group having an epoxy group. Examples of the group having an epoxy group include an epoxy group, a combination of an epoxy group and an alkylene group, and among them, a glycidyl group is preferable.

  The epoxy equivalent (g / eq) of the component (B1) is preferably 100 to 300, and more preferably 200 to 300. The epoxy equivalent (g / eq) is the molecular weight of the epoxy resin per epoxy group, and the smaller the value, the more epoxy groups in the resin. By using the component (B1) having a relatively small epoxy equivalent, the adhesion between the component (B1) and the adherend is good even when the amount of the component (B1) is set to a relatively small amount, and The component (B1) and the component (A) are sufficiently crosslinked.

  As such (B1) component, jER154, jER157S70, jER-157S65 manufactured by Mitsubishi Chemical Corporation; EPICLON N-730A, EPICLON, N-740, EPICLON N-770, EPICLON N-775 (above, manufactured by DIC) Commercial products such as trade names) can also be used.

..Oxazoline group-containing styrene resin The oxazoline group-containing styrene resin (hereinafter referred to as “(B2) component”) as the component (B) preferably has a number average molecular weight of 30,000 to 250,000.
When the component (B) contains (B2), the oxazoline group of the component (B) reacts with the acid functional group of the component (A) (for example, a carboxy group, a carboxylic acid group, etc.) to form a crosslinked structure. The For example, when the acid functional group of the component (A) is a carboxy group, the following crosslinking reaction occurs and an amide ester bond is formed. As a result, it is speculated that this cross-linked structure reinforces the strength of the resin and provides excellent durability as well as excellent adhesion.

The oxazoline group-containing styrene resin is a resin obtained by copolymerizing a styrene monomer and an oxazoline group-containing monomer.
Styrene and its derivatives can be used as the styrene monomer. Specifically, alkyl styrene such as styrene, α-methyl styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, octyl styrene; chloro; Examples thereof include halogenated styrene such as styrene, fluorostyrene, bromostyrene, dibromostyrene, and iodostyrene. Of these, styrene is preferable.

The oxazoline group-containing monomer is not particularly limited as long as it contains an oxazoline group and can be copolymerized with a styrenic monomer, but a monomer having an oxazoline group and a vinyl group is preferably used. Can be used.
Examples of the oxazoline group-containing vinyl monomer include 2-vinyl-2-oxazoline, 5-methyl-2-vinyl-2-oxazoline, 4,4-dimethyl-2-vinyl-2-oxazoline, and 2-isopropenyl-2-oxazoline. 4,4-dimethyl-2-isopropenyl-2-oxazoline, 4-acryloyl-oxymethyl-2,4-dimethyl-2-oxazoline, 4-methacryloyloxymethyl-2,4-dimethyl-2-oxazoline, 4, -Methacryloyloxymethyl-2-phenyl-4-methyl-2-oxazoline, 2- (4-vinylphenyl) -4,4-dimethyl-2-oxazoline, 4-ethyl-4-hydroxymethyl-2-isopropenyl- 2-oxazoline, 4-ethyl-4-carboethoxymethyl-2-isopropenyl-2- Kisazorin, and the like. Of these, 2-isopropenyl-2-oxazoline is preferable.
As such component (B2), commercially available products such as EPOCROS RPS-1005 (trade name) manufactured by Nippon Shokubai Co., Ltd. can be used.

  As the styrene monomer and the oxazoline group-containing monomer, one kind may be used alone, or two or more kinds may be used in combination.

.. Epoxy group-containing polyolefin resin (B) Epoxy group-containing polyolefin resin as component (hereinafter sometimes referred to as “component (B3)”) is a monomer containing an olefin compound and an epoxy group-containing vinyl monomer. A resin having a main chain obtained by copolymerization and a side chain bonded to the main chain.

-Main chain The main chain of the component (B3) is obtained by copolymerizing an olefin compound, an epoxy group-containing vinyl monomer, and other optional monomers used as necessary.
Examples of the olefin compound include olefin monomers such as ethylene, propylene, 1-butene, isobutylene, 1-hexene, and α-olefin.
Examples of the epoxy group-containing vinyl monomer include glycidyl esters such as glycidyl methacrylate (GMA) and glycidyl acrylate, glycidyl ethers such as allyl glycidyl ether, and epoxy alkenes such as epoxy butene.
As an olefin compound and an epoxy group-containing vinyl monomer, one kind may be used alone, or two or more kinds may be used in combination.

The main chain of the component (B3) may contain one or more other monomers in addition to the olefin compound and the epoxy group-containing vinyl monomer. Other monomers are not particularly limited as long as they are copolymerizable with olefin compounds and epoxy group-containing vinyl monomers. For example, (meth) acrylate monomers, (meth) acrylic ester monomers, (meth) acrylamide monomers And styrene monomer.
In the copolymer serving as the main chain of the component (B3), the constituent ratio of each monomer (compound) is not particularly limited, but is 10 to 10% relative to all monomers constituting the main chain of the component (B3). A copolymer obtained by copolymerizing 30% by mass, more preferably 10 to 20% by mass of an epoxy group-containing vinyl monomer is preferred. By using an epoxy group-containing vinyl monomer within the above range, it is possible to suitably improve the adhesion to the adherend.

  Among these, as the main chain of the component (B3), a copolymer obtained by copolymerizing an olefin compound and an epoxy group-containing vinyl monomer is preferable, and a copolymer of ethylene and glycidyl methacrylate is particularly preferable.

-Side chain (B3) A component can improve the characteristics, such as intensity | strength, adhesiveness, a synthesis | combination, of an olefin type copolymer, by having the side chain couple | bonded with the said principal chain. The side chain is not particularly limited. Styrenic resin (polymer containing styrene) such as polystyrene and styrene-acrylonitrile copolymer; (meth) methyl acrylate, (meth) ethyl acrylate, (meth) Examples thereof include (meth) acrylic resins obtained by polymerizing one or more alkyl (meth) acrylate monomers such as butyl acrylate and pentyl (meth) acrylate.
Especially, as a side chain of (B) component, the polymer containing styrene is preferable, for example, a polystyrene and a styrene-acrylonitrile copolymer are mentioned. Of these, polystyrene is particularly preferable.
When the component (B3) is a polymer containing polystyrene as a side chain, fluidity in a molten state is improved. For this reason, it is considered that the hot melt adhesive resin film of the present invention has appropriate fluidity when heated and bonded, and the epoxy group is easily brought into contact with the adherend, thereby improving the adhesive strength and durability.

The component (B3) having the main chain and side chain as described above includes, for example, a main chain copolymer obtained by a conventional method, a monomer constituting the side chain, an organic peroxide, an aliphatic azo compound, and the like. Can be obtained by graft polymerization using a radical polymerization initiator.
The melting point of the component (B3) is 80 to 120 ° C, and preferably 90 to 110 ° C.
The component (B3) having such a melting point can be obtained by appropriately selecting the monomer species constituting the main chain and the side chain.
By using the component (B3) having a melting point in the above range, the component (A) and the component (A) can be used at a temperature sufficiently higher than the melting point of the component (B3) even when using a conventional method and a general apparatus. It becomes possible to melt-knead the component (B3). Moreover, the adhesive agent and adhesive layer which have the outstanding durability can be obtained. Furthermore, when making the said (A) component and (B3) component react using melt kneading | mixing, it is preferable that melting | fusing point of (B3) component is low compared with (A) component. By using the component (B3) having a melting point in the above range, the degree of freedom in selecting the component (A) can be increased.

  As such component (B3), commercially available products such as MODIPER A1100, A4100, and A4400 (all trade names) manufactured by NOF Corporation may be used.

In this embodiment, both the acid functional group of the component (A) and the epoxy group of the component (B3) are adhesive functional groups for the adherend (particularly functional groups such as hydroxyl groups of the adherend). By functioning, it is considered that excellent adhesion to various adherends such as metal, glass, and plastic can be achieved.
In addition, a part of the acid functional group of the component (A) and a part of the epoxy group of the component (B3) react to form a crosslinked structure of the component (A) and the component (B3). It is considered that the strength of the resin is reinforced and good durability is obtained together with excellent adhesiveness.

In addition, the component (B3) may contain one or more other monomers in addition to the styrene monomer and the epoxy group-containing monomer. Other monomers are not particularly limited as long as they are copolymerizable with these monomers, and examples include (meth) acrylate monomers, (meth) acrylic ester monomers, (meth) acrylamide monomers, and the like.
In the component (B3), the constituent ratio of each monomer is not particularly limited, but is 5 to 50% by mass, more preferably 10 to 30% by mass, based on the total monomers constituting the component (B3). A resin obtained by copolymerizing a group-containing monomer is preferred. By using the oxazoline group-containing monomer within the above range, the component (A) and the component (B3) can be sufficiently cross-linked to obtain good durability.

  The number average molecular weight of the component (B3) is 30,000 to 250,000, preferably 50,000 to 200,000, more preferably 60,000 to 100,000, and most preferably 60,000 to 80,000. By using the component (B3) having a number average molecular weight within the above range, the compatibility between the component (A) and the component (B3) is improved, and the component (A) and the component (B3) are sufficiently crosslinked. Is possible.

  As such component (B3), commercially available products such as MODIPER A1100, A4100, and A4400 (all trade names) manufactured by NOF Corporation can be used.

  In this embodiment, (B) component is contained with 1-20 mass parts with respect to (A) component 80-99 mass parts. Especially, it is preferable that (B) component is contained 1-15 mass parts with respect to (A) component 85-99 mass parts.

  The hot melt adhesive resin film of the present embodiment preferably further contains an elastomer resin. By containing the elastomer resin, the adhesion to the adherend can be maintained.

-Elastomer resin Elastomer resin (hereinafter referred to as “component (C)”) may be any component having properties as an elastomer. Styrenic elastomer, acrylic elastomer, urethane elastomer, olefin elastomer, ester An elastomer etc. are mentioned.
Of these, olefin-based elastomers are preferable, and examples thereof include block copolymers having a hard segment made of polystyrene or the like and a soft segment made of polyethylene, polybutadiene, polyisoprene, or the like. Examples of the olefin polymer usable in the olefin elastomer include aromatic olefin-aliphatic olefin copolymers such as styrene-butadiene copolymer, styrene-isoprene copolymer, and styrene-ethylene copolymer. .

  In this embodiment, the olefin-based elastomer is a styrene-ethylene-butylene-styrene copolymer (SEBS) obtained by hydrogenating a styrene-butylene-styrene copolymer (SBS) to completely open an unsaturated bond in the molecule. Or a propylene-based elastomer having good compatibility with polypropylene.

In this embodiment, examples of the component (C) include Dynalon from JSR Corporation, Tuftec H Series from Asahi Kasei Chemicals Corporation, and Kraton G Polymer from Kraton Polymer Corporation.
Examples of the propylene elastomer include Tough Selenium manufactured by Sumitomo Chemical Co., Ltd. and El Modu Co., Ltd. of Idemitsu Kosan Co., Ltd.

  In this embodiment, when a hot-melt-adhesive resin film contains (C) component, high adhesiveness can be exhibited with respect to a metal. The reason is guessed as follows. When the maleic anhydride in the component (A) and the epoxy group in the component (B) are bonded to the adherend, thermal energy is required. On the other hand, thermal energy is also consumed when the surface layer resin of the hot-melt adhesive resin film melts in the thermocompression bonding step. The elastomer component which is the component (C) has a low softening point and is easily melted even at a low temperature. Therefore, it is considered that the amount of heat energy consumed in the surface layer can be reduced. For this reason, it is guessed that the high adhesiveness with the metal which can supply the thermal energy required in order for (A) component and (B) component to couple | bond with an adherend can fully be exhibited.

In this embodiment, when the component (A) and the component (B) are essential components and the component (C) is further contained, the compounding ratio of the component (C) is the ratio between the component (A) and the component (B). (C) 1 mass% or more and 20 mass% or less are preferable in the total amount of a component.
More specifically, the content of the component (B) is preferably 1 to 5 parts by mass and the content of the component (C) is preferably 1 to 10 parts by mass with respect to 80 to 90 parts by mass of the component (A). .
By making each compounding quantity of (A) component, (B) component, and (C) component into said range, the high adhesiveness with respect to a metal can be exhibited.

(Peeling test conditions)
The hot melt adhesive resin film of the present embodiment has a peel strength measured under the following peel test conditions of 0.5 N / mm or more, preferably 0.6 N / mm or more, and 0.8 N / mm or more. More preferably, 1.0 N / mm or more is particularly preferable. High durability can be exhibited by setting it within this range.
Although an upper limit is not specifically limited, For example, it can be 3.0 N / mm or less and 2.0 N / mm or less.
When the peel strength is not less than the above lower limit, particularly high adhesion to metal can be exhibited.

The underwater peel strength test will be described with reference to FIGS.
For the peel test, the laminate shown in FIG. 4 is used as a test piece. The test piece is an aluminum foil 31 having a thickness (L ₃ ) of 30 μm, a length (L ₁ ) of 50 mm × a width (L ₂ ) of 10 mm, a thickness (L ₆ ) of 30 μm, and a length (L ₄ ) of 50 mm × width ( L ₅ ) Stainless steel foil 32 cut to 10 mm is used. An aluminum foil 31, a hot melt adhesive resin film 30 cut to L7: 10 mm and L8: 10 mm, and a stainless steel foil 32 are laminated in this order with one end aligned, and while applying a pressure of 0.5 MPa, 150 Let the laminated body bonded together at 5 degreeC for 5 second be a test piece.

This laminated body is put into the water tank 37 shown in FIG. 3, and is immersed in 95 degreeC pure water (code | symbol 36) for 500 hours.
Thereafter, the aluminum foil 31 and the stainless steel foil 32 are bent at the positions of the ends of the hot-melt adhesive resin film 30 so that the aluminum foil 31 is on the tension side in water, and is gripped by the gripping tool 33, and the stainless steel foil 32. Is gripped by the gripping tool 34 and fixed, and the aluminum foil 31 is pulled in the water tank 37 in the tensile direction indicated by reference numeral 35 and the peel strength is measured. The tensile speed is 300 mm / min. The above description is an example, and the stainless steel foil may be gripped with a gripping tool so as to be on the tension side.

[Method for producing hot melt adhesive resin film]
The hot melt adhesive resin film of the present invention can be produced by melt-kneading the above component (A), component (B), and optional component (C), followed by extrusion molding.

<< Second Embodiment >>
The hot melt adhesive resin laminate of the present embodiment includes a first surface layer, a first intermediate layer made of polyolefin resin, a base material layer, a second intermediate layer made of polyolefin resin, and a second surface layer. Are stacked in this order. In the present embodiment, at least one of the first surface layer and the second surface layer is made of the hot melt adhesive resin film of the first embodiment of the present invention.

  The hot melt adhesive resin laminate of the present embodiment exhibits excellent adhesion to various adherends, particularly metals. Furthermore, the hot melt adhesive resin laminate of the present embodiment can maintain particularly high adhesion to metal. Moreover, the hot melt adhesive resin laminate of the present embodiment can maintain high adhesiveness even when used in a high temperature and high humidity environment.

The hot melt adhesive resin laminate of the present embodiment has a peel strength of 0.5 N / mm or more, preferably 0.8 N / mm or more when the above (peel test conditions) is performed, and 1.0 N / mm. The above is more preferable.
When the peel strength is not less than the above lower limit, particularly high adhesion to metal can be exhibited.

FIG. 2 is a cross-sectional view showing a schematic configuration of a hot-melt adhesive resin laminate according to the second embodiment of the present invention.
As shown in FIG. 2, the hot melt adhesive resin laminate 2 of the present embodiment includes a base material layer 23, a first intermediate layer 22 laminated on one surface of the base material layer 23, and the base material layer 23. A second intermediate layer 24 laminated on the other surface, a first surface layer 21 laminated on a surface opposite to the base material layer 23 of the first intermediate layer 22, and a base material layer 23 of the second intermediate layer 24; And a second surface layer 25 laminated on the opposite surface.
That is, as shown in FIG. 2, the hot melt adhesive resin laminate 2 has a first surface layer 21 / first intermediate layer 22 / base material layer 23 / second intermediate layer 24 / second surface layer 25 in this order. It consists of a five-layered structure.

-Base material layer As resin which comprises the base material layer 23, resin with sufficient heat resistance is preferable, for example, polyester resins, such as a polyethylene naphthalate (PEN), a polyethylene terephthalate (PET), a polybutylene terephthalate (PBT) A synthetic resin film made of a polyolefin polymer such as a cyclic olefin polymer (COP) or a methylpentene polymer (TPX).
The resin used for the base material layer 23 is preferably at least one selected from the group consisting of polyethylene naphthalate, cycloolefin polymer, cycloolefin copolymer, methylpentene polymer, acrylic resin, and polycarbonate.

The thickness of the base material layer 23 is preferably 25 μm to 250 μm, more preferably 40 μm to 220 μm, and particularly preferably 100 μm to 200 μm.
The thickness of the base material layer 23 is the thickness of the entire hot melt adhesive resin laminate 2 (that is, the base material layer 23, the first intermediate layer 22, the second intermediate layer 24, the first surface layer 21 and the second surface). About 30% to 80% of the total thickness of the layer 25 is preferable.

-1st and 2nd intermediate | middle layer Resin which comprises the 1st intermediate | middle layer 22 and the 2nd intermediate | middle layer 24 is resin which expresses favorable adhesiveness with respect to polyolefin resin, such as a polypropylene. Specifically, as the resin constituting the first intermediate layer 22 and the second intermediate layer 24, it is preferable to use a resin in which a copolymer of propylene and 1-butene is modified with maleic acid.
The first intermediate layer 22 and the second intermediate layer 24 are preferably provided by coating. From the viewpoint of the adhesive strength between the layers, the thicknesses of the first intermediate layer 22 and the second intermediate layer 24 are 0.5 μm to 10 μm, respectively. It is preferable that it is 1 micrometer-5 micrometers.

  The first intermediate layer and the second intermediate layer preferably contain a compound containing an epoxy group, an oxazoline compound, or an isocyanate compound as a crosslinking agent, and more preferably contain a compound containing an epoxy group or an isocyanate compound. preferable. By adding these cross-linking agents, the cross-linking can be increased by drying after film formation, laminating with the surface layer, or heating in the subsequent heating step, thereby increasing the molecular cross-linking of the intermediate layer.

-1st, 2nd surface layer In this embodiment, the hot-melt-adhesive resin film of 1st Embodiment of the said this invention is used for a 1st, 2nd surface layer.

[Method for producing hot-melt adhesive resin laminate]
As a manufacturing method of the hot-melt-adhesive resin laminate which is one embodiment of the present invention, for example, there are a solution casting method, a film formation by a melt casting method, and a lamination method by coating and a lamination method by a melt extrusion method. Moreover, it can be set as a laminated film combining these.
The base material layer 23 is preferably formed by a melt casting method.
In the hot melt adhesive resin laminate of the present invention, the first intermediate layer 22 and the second intermediate layer 24 can be either formed by coating or laminated on a base material layer by a melt extrusion method. Among these, the first intermediate layer 22 and the second intermediate layer 24 are preferably laminated by coating.
In the hot melt adhesive resin laminate of the present invention, the first surface layer 21 and the second surface layer 25 are formed by film formation by a solution pouring method or film formation by a melt pouring method, and then laminating and coating. Either a lamination method or a lamination method by a melt extrusion method can be employed. In the present invention, it is preferable to form a film by the melt-flow method and then laminate.
When the first surface layer 21 and the second surface layer 25 are provided by film formation by the melt flow method, the melt flow is formed as a single layer film separately from the base material layer 23, the first intermediate layer 22, and the second intermediate layer 24. It is preferable to form a film. A film to be a surface layer formed by melt flow is formed as a first surface layer 21 and a second surface layer 25 on the surface of the first intermediate layer 22 / base material layer 23 / second intermediate layer 24 laminate. Can be laminated. At this time, the first intermediate layer 22 and the second intermediate layer 24 also function as a laminating adhesive.
When the surface layer is provided by solution pouring, either the method of providing the first surface layer 21 and the second surface layer 25 by sequentially applying and drying, or the method of providing by applying and drying the front and back at the same time can be adopted. it can.

<Laminate>
The laminate of the present invention comprises the first adherend, the hot-melt adhesive resin film or hot-melt adhesive resin laminate of the present invention, and the first adherend in this order.
Since the adhesive layer is formed from the hot melt adhesive resin film or hot melt adhesive resin laminate of the present invention, good adhesion and durability can be obtained even when adherends are bonded together. Is possible.
As the adherend to be bonded using the laminate of the present invention, various adherends such as metal, glass and plastic can be used. Since the hot-melt adhesive resin film or hot-melt adhesive resin laminate of the present invention can exhibit high adhesiveness to metals, metals can be suitably used as adherends.
As the metal, a generally known metal plate, metal flat plate or metal foil can be used. Examples of the metal used for these include iron, copper, aluminum, lead, zinc, titanium, and chromium, and may also be stainless steel that is an alloy. Moreover, you may use the metal or nonmetal which carried out the surface processing process by the metal plating or the coating process by the coating material containing a metal as a to-be-adhered body. Particularly preferably, it is a metal flat plate or metal foil made of iron, aluminum, titanium, stainless steel, surface-treated metal, and by using these as an adherend, the hot melt adhesive resin film of the present invention or The hot melt adhesive resin laminate exhibits particularly strong adhesive strength.

    EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.

<Underwater peel strength test>
The underwater peel strength test will be described with reference to FIG.
First, the laminate shown in FIG. 4 was used as a test piece. The hot-melt adhesive resin film or hot-melt adhesive resin laminate 30 of each example and 10 mm is applied to an aluminum foil 31 having a thickness (L ₃ ) of 30 μm and a length (L ₁ ) of 50 mm × width (L ₂ ) of 10 mm. Laminations of (L ₇ ) × 10 mm (L ₈ ) are laminated, and a stainless steel foil 32 cut into a thickness (L ₆ ) of 30 μm, length (L ₄ ) of 50 mm × width (L ₅ ) of 10 mm is laminated thereon. The laminate was laminated by applying it at 150 ° C. for 5 seconds while applying a pressure of 0.5 MPa. As shown in FIG. 4, the lamination was performed with one end aligned.
This laminate was immersed in 95 ° C. pure water (reference numeral 36) for 500 hours.
Thereafter, the aluminum foil 31 and the stainless steel foil 32 are bent at the positions of the ends of the hot-melt adhesive resin film 30 so that the aluminum foil 31 is on the tension side in water, and is gripped by the gripping tool 33, and the stainless steel foil 32. Was gripped and fixed by the gripping tool 34, and the aluminum foil 31 was pulled in the tensile direction indicated by the reference numeral 35 in the water tank 37, and the peel strength was measured.
The tensile speed was measured at 300 mm / min.

<Durability test>
The same laminate as the test piece used in the above <underwater peel strength test> was used as the test piece.
The obtained laminate was put into a high-temperature thermo-machine at 80 ° C. and 95% humidity for 1000 hours.
Thereafter, the laminate was taken out, the state of the laminate was observed, and peeling was observed visually. The results are shown in the table below.
Evaluation was performed based on the following evaluation criteria.
(Double-circle): There was no visible peeling and it was favorable.
○: Visible and conspicuous peeling was not seen.
Δ: Peeling was observed in some places.
X: Peeling was observed on the entire surface.
XX: Many peelings were observed on the entire surface.

<Manufacture of hot melt adhesive resin film>
The components (A), (B) and (C) shown in Table 1 below are melt-kneaded at 280 ° C. for 2 minutes and then formed into a 30 μm film by extrusion to produce surface layers 1 to 10 and hot melt An adhesive resin film was obtained. When this hot-melt adhesive resin film has a five-layer structure, it becomes a surface layer.

In Table 1, each symbol means the following components. The numerical value in [] is a compounding amount (mass%).
(A) -1: Maleic anhydride modified polypropylene.
(B) -1: Epoxy resin A compound of the above formula (1), wherein R ^{1 to} R ⁶ are each independently a methyl group, n = 5, and R ^X is an epoxy group; softening point = 70 ° C; epoxy equivalent weight = 210).
(B) -2: Glycidyl methacrylate-modified olefin “Modiper A4100” (trade name, manufactured by NOF Corporation) (graft polymer of ethylene-glycidyl methacrylate copolymer and polystyrene; glycidyl for all monomers in the main chain) Ratio of methacrylate monomer = 70% by mass; melting point 97 ° C.).
-(B) -3: oxazoline group-containing styrene resin "Epocross RPS-1005" (trade name, manufactured by Nippon Shokubai Co., Ltd.) (resin obtained by copolymerizing styrene and 2-isopropenyl-2-oxazoline; Average molecular weight = 70,000).
・ (C) -1: Propylene elastomer (Tough Selenium-Sumitomo Chemical)
・ (C) -2: Polyethylene elastomer

<Manufacture of intermediate layer>
A base material component (component (A)), a crosslinkable component (component (B)) and other components shown in Table 2 below are dissolved in a solvent of toluene and ethyl acetate to form a coating solution for forming an intermediate layer. Created. The composition of the material used as the raw material for the intermediate layer is shown in the following table.

In Table 2, each symbol means the following components. The numerical value in [] is a compounding amount (mass%).
(A) -1: Maleic anhydride modified polypropylene (A) -2: Carboxylic acid modified polypropylene (B) -1: Epoxy resin Compounds of general formula (1), wherein R ^{1 to} R ⁶ are each Independently a methyl group, n = 5, and R ^X is an epoxy group (phenol novolac type epoxy resin having a bisphenol A structure; softening point = 70 ° C .; epoxy equivalent = 210)
(D) -1: Isocyanurate: Isocyanurate of hexamethylene diisocyanate (HDI)

  The coating liquid for forming the obtained intermediate layer is applied on both sides of the substrate and dried, and the intermediate layer is formed so that the thickness of the intermediate layer after drying is 3 μm. A laminate having a layer structure of / base material layer / second intermediate layer was produced.

<< Examples 1-1 to 1-6, Comparative Examples 1-1 to 1-3; Production of Hot Melt Adhesive Single Layer Resin Film >>
The hot-melt adhesive resin film obtained above was used as a surface layer and laminated on both surfaces of the laminate comprising the intermediate layer / base material layer / intermediate layer structure obtained above to obtain a surface layer / intermediate layer. A hot-melt adhesive resin film having a five-layer structure of / base material layer / intermediate layer / surface layer was produced.
As the surface layer, the surface layers 1 to 10 obtained above were used as hot-melt adhesive single layer resin films. For the hot melt adhesive single layer resin films of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-3, the results of underwater peel strength and the results of the durability test are shown in Table 3 below.

  As shown in the above results, Examples 1-1 to 1-6 have high durability because the metal plates do not peel off even when exposed to harsh conditions of 120 hours at 120 ° C. Was. On the other hand, in Comparative Examples 1-1 to 1-3 in which the present invention is not applied, the metal plates are separated from each other.

<< Examples 2-1 to 2-12, Comparative Examples 2-1 to 2-5; Production of hot-melt adhesive five-layer resin laminate >>
The hot melt adhesive resin film obtained above is used as a surface layer, and the first intermediate layer, the base material layer, and the second intermediate layer obtained above are laminated on both surfaces of the laminate in this order. A hot-melt adhesive resin film having a five-layer structure having a first surface layer, a first intermediate layer, a base material layer, a second intermediate layer, and a second surface layer in this order was produced. At this time, the layers were laminated so that the configurations of the layers were as shown in Tables 4-6.

In Tables 4-6, each material means the following.
-Surface layers 1-10: Surface layers 1-10 shown in Table 1.
Intermediate layers 1 to 4: Intermediate layers 1 to 4 shown in Table 2.
TPX: A layer made of methylpentene polymer.
COC: a layer composed of a cyclic olefin copolymer.
PEN: a layer made of polyethylene naphthalate.

  As shown in the above results, Examples 2-1 to 2-12 have high durability because the metal plates do not peel off even when exposed to harsh conditions of 120 hours at 120 ° C. Was. On the other hand, in Comparative Examples 2-1 to 2-5 to which the present invention is not applied, the metal plates are separated from each other.

    1: hot melt adhesive resin film, 2: hot melt adhesive resin laminate, 21, 25: surface layer, 22, 24: intermediate layer, 23: substrate layer, 30: hot melt adhesive resin film or hot melt Adhesive resin laminate, 31: aluminum foil, 32: stainless steel foil, 33, 34: gripping tool, 36: water, 37: water tank

Claims (11)

An acid-modified polyolefin resin and a crosslinkable resin are contained, and the content of the crosslinkable resin is 1% by mass or more and 20% by mass or less based on the total amount of the acid-modified polyolefin resin and the crosslinkable resin. A hot melt adhesive resin film having a peel strength of 0.5 N / mm or more when a peel test is conducted under the following conditions.
(Peeling test conditions)
Test piece: A laminate in which an aluminum plate and a stainless steel plate are heat-bonded with a hot-melt adhesive resin film. The shapes of the aluminum plate and the stainless plate are 10 mm width, 50 mm length, and 30 μm thickness, respectively. The shape of the hot melt adhesive resin film is 10 mm × 10 mm.
Test conditions: The laminate is immersed in pure water at 95 ° C. for 500 hours. Thereafter, either the aluminum plate or the stainless steel plate of the laminate is fixed in 95 ° C. water, and the peel strength when the other is pulled at a pulling speed of 300 mm / min is measured.  Furthermore, elastomer resin is contained, The content of the said elastomer resin is 1 mass% or more and 20 mass% or less with respect to the total amount of the said acid-modified polyolefin resin, the said crosslinkable resin, and the said elastomer resin. The hot melt adhesive resin film as described.   The hot melt adhesive resin film according to claim 2, wherein the elastomer resin is an olefin resin.   The said crosslinkable resin is 1 or more types selected from the group which consists of a phenol novolak modified | denatured epoxy resin, an oxazoline group containing styrene resin, or an epoxy group containing polyolefin resin of any one of Claims 1-3. Hot melt adhesive resin film. A first surface layer, a first intermediate layer made of a polyolefin resin, a base material layer, a second intermediate layer made of a polyolefin resin, and a second surface layer are laminated in this order, and the first surface At least one of the layer and the second surface layer is a hot melt adhesive resin laminate comprising the hot melt adhesive resin film according to any one of claims 1 to 4,
A hot melt adhesive resin laminate having a peel strength of 0.5 N / mm or more when a peel test is performed under the following conditions.
(Peeling test conditions)
Test piece: A laminate in which an aluminum plate and a stainless steel plate are heated and bonded with a hot-melt adhesive resin laminate. The shapes of the aluminum plate and the stainless plate are 10 mm width, 50 mm length, and 30 μm thickness, respectively. The shape of the hot melt adhesive resin laminate is 10 mm × 10 mm.
Test conditions: The laminate is immersed in pure water at 95 ° C. for 500 hours. Thereafter, either the aluminum plate or the stainless steel plate of the laminate is fixed in 95 ° C. water, and the peel strength when the other is pulled at a pulling speed of 300 mm / min is measured.   The hot-melt-adhesive resin laminate according to claim 5, wherein the first intermediate layer and the second intermediate layer each have a thickness of 1 µm to 5 µm.   The hot melt adhesive resin laminate according to claim 5 or 6, wherein the first intermediate layer and the second intermediate layer are composed of a modified polyolefin resin and a compound containing an epoxy group.   The hot melt adhesive resin laminate according to any one of claims 5 to 7, wherein the first intermediate layer and the second intermediate layer are composed of a modified polyolefin resin and an isocyanate compound.   The said base material layer consists of 1 or more types selected from the group which consists of a polyethylene naphthalate, a cycloolefin polymer, a cycloolefin copolymer, a methyl pentene polymer, an acrylic resin, and a polycarbonate in any one of Claims 5-8. The hot melt adhesive resin laminate described.   The laminated body containing the hot-melt-adhesive resin film of any one of Claims 1-4, and a to-be-adhered body.   The laminated body containing the hot-melt-adhesive resin laminated body of any one of Claims 5-9, and a to-be-adhered body.

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