JP5049541B2 - Adhesive resin composition - Google Patents

Description

  The present invention relates to an adhesive resin composition, and more specifically, can be formed into a film by extrusion lamination, and has an adhesion property to both a polar material such as metal and glass and a nonpolar material such as polyethylene and polypropylene. The present invention relates to a resin composition that develops from a low sealing temperature.

  Conventionally, it is possible to form a film by extrusion lamination, and as a resin composition having adhesion to nonpolar materials such as polyethylene, polypropylene, polystyrene, etc., low-density polyethylene, ethylene-α / olefin, polypropylene, ethylene- A resin composition obtained by blending an ethylene polymer such as an unsaturated ester copolymer and a tackifying resin is known. Resin composition that exhibits adhesiveness even at low sealing temperatures when a high unsaturated ester content of an ethylene-unsaturated ester copolymer or a high melt flow rate (hereinafter sometimes abbreviated as MFR) is used. Can be obtained. However, there is almost no adhesion to polar materials such as glass and metal.

  On the other hand, it can be made into a film by extrusion lamination, and as a resin having adhesion to metals such as aluminum and polar materials such as glass and polyester, ethylene-unsaturated carboxylic acid copolymer and ethylene-vinyl acetate copolymer Known are graft-modified products obtained by grafting unsaturated carboxylic acids or their derivatives to ethylene-based polymers such as saponified polymers, ethylene-α / olefin copolymers, ethylene-unsaturated ester copolymers, etc. A resin composition obtained by blending these with a tackifying resin is known. Since a graft modified product obtained by grafting an unsaturated carboxylic acid or a derivative thereof has adhesion to polar materials such as metals and glass and polyester, a resin composition containing the same is used, for example, as a packaging film. Used as interlayer adhesive resin for multilayer films made of polyvinyl alcohol, polycarbonate, ionomer, polyamide, polyester, polystyrene, polyvinyl chloride, polymethylene methacrylate, polypropylene, etc., interlayer film for laminated glass, sealing layer for container lids, etc. It has been.

  A resin composition of an ethylene / α-olefin grafted with an unsaturated carboxylic acid or derivative thereof, an ethylene-unsaturated ester copolymer, and a tackifying resin has been proposed. In general, however, the melting point of ethylene / α-olefin is higher than that of the ethylene-unsaturated ester copolymer, and the melting point of the graft modified product of the unsaturated carboxylic acid is also high. Adhesiveness is often not expressed.

  In recent years, performance required for adhesive films has been diversified due to diversification of lifestyles. For example, when an adherend is low in heat resistance, heat sealing cannot be performed at a high temperature. In that case, the adhesive film is required to have a performance capable of obtaining sufficient adhesiveness even when heat-sealed at a low temperature (hereinafter sometimes abbreviated as low-temperature sealability). Furthermore, in fields such as industrial materials and electronic equipment, an adhesive film that adheres to both polar and nonpolar materials may be required. Therefore, a resin composition having a low-temperature sealing property for both polar and nonpolar materials and a laminated film obtained by forming the resin composition by extrusion lamination are very useful. It seems that things have not yet been obtained.

  As a result of repeated studies by the present applicants, when the component (A) and the component (B) of the present application are combinations of components specified in the present application and have a specific MFR as a composition, An unsaturated ester content of 3 to 40% by weight, an MFR of 10 to 100 g / 10 min of an ethylene-unsaturated ester copolymer 40 to 80 wt%, an MFR of 2 to 50 g / 10 min of α, β-unsaturated An extruded laminator having a MFR of 20 to 100 g / 10 min comprising 10 to 40% by weight of an ethylene-unsaturated ester copolymer graft-modified with a carboxylic acid or a derivative thereof and 10 to 30% by weight of a tackifier resin It has been found that the film can be made into a film by the above-described method, and the adhesiveness is exhibited from both low and high polar materials.

  Patent Document 1 includes (a) about 30 to 70% by weight of at least one ethylene-α / olefin copolymer or ethylene-ethylenically unsaturated ester copolymer, and (b) any one of these copolymers. There has been proposed a resin composition obtained by melt-mixing 10 to 60% by weight of a graft-modified product obtained by grafting an unsaturated carboxylic acid or an acid anhydride thereof and (c) 10 to 30% by weight of a tackifier resin. However, the components (a) and (b) of Patent Document 1 are not a combination of the components specified in the present application, and do not have a specific MFR as a composition, so that the low-temperature sealability is poor. It may become a thing.

  Patent Document 2 discloses an ethylene / α, β-unsaturated carboxylic acid copolymer or an ethylene / α, β-unsaturated carboxylic acid / α, β-unsaturated carboxylic acid ester copolymer (A) of 10 to 80 weights. 10 to 80 parts by weight of an ethylene / α, β-unsaturated carboxylic acid ester copolymer (B) partially or entirely graft-modified with an unsaturated dicarboxylic acid or an anhydride thereof and a tackifier resin (C) 5 A resin composition consisting of ˜30 parts by weight has been proposed. However, since the component (A) and the component (B) in Patent Document 2 are not a combination of components specified in the present application and further have no specific MFR as a composition, Although it has adhesiveness, the low temperature sealing property may be insufficient.

Patent Document 3 discloses (a) an ethylene / unsaturated ester copolymer having an unsaturated ester content of 5 to 35% by weight, 35 to 90% by weight, and (b) a low crystalline or crystalline ethylene / α-olefin. From 5 to 40% by weight of graft modified product of unsaturated carboxylic acid or anhydride of ethylene copolymer selected from copolymer or ethylene / unsaturated ester copolymer and (c) 5 to 25% by weight of tackifying resin A resin composition is proposed. It is said that the MFR of the ethylene / unsaturated ester copolymer is 0.1 to 20 g / 10 min, particularly 0.3 to 10 g / 10 min. When used, the MFR of the resin composition becomes small, and it is difficult to obtain a resin composition having a low temperature sealing property. This is an important factor for low temperature sealability. Also in patent document 3, when (a) component and (b) component are the combination of the components specified by this application, and also have specific MFR as a composition, of polar material and nonpolar material There is no description or suggestion that adhesiveness develops at low sealing temperatures in both.
Japanese Patent No. 1773742 Japanese Patent No. 2503260 Japanese Patent No. 3048002

  The present invention provides a resin composition that can be formed into a film by extrusion lamination, and is expressed from a sealing temperature with low adhesion to both polar materials such as metal and glass and nonpolar materials such as polyethylene and polypropylene. The purpose is to do.

The present invention is an ethylene- vinyl acetate copolymer (A) 40-80% by weight having an unsaturated ester content of 3-40% by weight and a melt flow rate of 10-100 g / 10 min.
10 to 40% by weight of an ethylene- vinyl acetate copolymer (B) graft-modified with an α, β-unsaturated carboxylic acid or derivative thereof having a melt flow rate of 2 to 50 g / 10 min;
The present invention relates to an adhesive resin composition having a melt flow rate of 20 to 100 g / 10 min comprising 10 to 30% by weight of a tackifying resin (C) using a petroleum tackifying resin and a rosin tackifying resin .

  Furthermore, the present invention relates to an adhesive resin composition, wherein the α, β-unsaturated carboxylic acid is at least one of acrylic acid, methacrylic acid, itaconic acid, and maleic acid.

  Furthermore, the present invention is a resin in which an ethylene-unsaturated ester copolymer (B) graft-modified with an α, β-unsaturated carboxylic acid or a derivative thereof is grafted in a molten state in the presence of a radical initiator. It is related with the adhesive resin composition characterized by these.

  Furthermore, the present invention provides an adhesive film obtained by laminating an adhesive resin composition on a base material on which a metal foil is laminated, or on a base material on which any of metal, metal oxide, and inorganic oxide is deposited. About.

  According to the present invention, there is provided a resin composition which can be formed into a film by extrusion lamination and has a low adhesiveness to both a polar material such as metal and glass and a nonpolar material such as polyethylene and polypropylene from a sealing temperature. I was able to.

  The adhesive resin composition of the present invention has an unsaturated ester content of 3 to 40% by weight, an MFR of 10 to 100 g / 10 min of ethylene-unsaturated ester copolymer (A) 40 to 80% by weight, and an MFR of 2 10 to 40% by weight of an ethylene-unsaturated ester copolymer (B) graft-modified with an α, β-unsaturated carboxylic acid or derivative thereof of ˜50 g / 10 min, and 10 to 30% by weight of a tackifier resin (C) Consists of.

  The MFR of the adhesive resin composition of the present invention is 20 to 100 g / 10 min. Preferably it is 20-70 g / 10min, More preferably, it is 30-50 g / 10min. If the MFR is 10 g / 10 min or less, it tends to be inferior in low-temperature sealability, and if it is 100 g / 10 min or more, it tends to be difficult to form a film by extrusion lamination.

  As an unsaturated ester monomer of the ethylene-unsaturated ester copolymer (A) in the present invention, methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, Examples thereof include unsaturated carboxylic acid esters such as isobutyl methacrylate, dimethyl maleate and diethyl maleate, and vinyl esters such as vinyl acetate and vinyl propionate.

  The ethylene-unsaturated ester copolymer (A) in the present invention may be any of the above types, but an ethylene-vinyl acetate copolymer (hereinafter sometimes abbreviated as EVA) is preferably used. The melt flow rate of the ethylene-unsaturated ester copolymer is 10 to 100 g / 10 min. Preferably it is 20-50 g / 10min, More preferably, it is 30-50 g / 10min. The melt flow rate is an outflow amount (g / 10 minutes) at 190 ° C. and a load of 2160 g, measured according to JIS K 7210. The unsaturated ester content is 3 to 40% by weight. Preferably it is 3 to 15 weight%, More preferably, it is 3 to 7 weight%.

  As the α, β-unsaturated carboxylic acid of the ethylene-unsaturated ester copolymer (B) graft-modified with α, β-unsaturated carboxylic acid or a derivative thereof in the present invention, maleic acid, acrylic acid, methacrylic acid And itaconic acid. Among these, maleic acid is preferably used.

  Examples of the derivatives of α, β-unsaturated carboxylic acids in the present invention include acid anhydrides, acid esters, acid amides, acid halides and the like. Of these, acid anhydrides are preferred.

  The ethylene-unsaturated ester copolymer (B) graft-modified with an α, β-unsaturated carboxylic acid or derivative thereof in the present invention may be generally commercially available, for example, HPR VR101, HPR VR103, HPR VR105. -1 (manufactured by Mitsui DuPont Polychemical Co., Ltd.), OREVAC G 18211 (manufactured by Arkema Co., Ltd.) and the like.

  In addition, ethylene-unsaturated ester copolymer is grafted with α, β-unsaturated carboxylic acid or its derivative obtained by grafting α, β-unsaturated carboxylic acid or its anhydride in the molten state in the presence of a radical initiator. A modified ethylene-unsaturated ester copolymer can also be used. A method of grafting an ethylene-unsaturated ester copolymer in the molten state with an α, β-unsaturated carboxylic acid or anhydride thereof in the presence of a radical initiator is already known from JP-A-11-335427.

  Any radical initiator may be used as long as it is generally used for polyolefin grafting. Among them, those having a one-minute half-life temperature in the range of 120 to 200 ° C. are preferable. Specifically, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, t-hexylperoxy 2-ethylhexanoate, t-butylperoxy 2-ethylhexanoate, benzoyl peroxide, t-butylperoxyisobutyrate, 1,1-bis (t-hexylperoxy) -3,3,5 -Trimethylcyclohexane, 1,1-bis (t-hexylperoxy) -cyclohexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butyl) Peroxy) cyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, t-butylperoxylaurate, t-butyl par Oxyisopropyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxyacetate, 2,2-bis (t-butylperoxy) butane , T-butyl peroxybenzoate, n-butyl-4,4-bis (t-butylperoxy) valerate, di-t-butylperoxyisophthalate, α, α′-bis (t-butylperoxy) diisopropylbenzene , Dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5 -Di (t-butylperoxy) hexyne-3 etc. are mentioned. Examples of the azo initiator include diazo compounds such as azodiisobutyronitrile. In the grafting of EVA resin, α, α′-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne- 3 etc. are preferable.

  The melt flow rate of the ethylene-unsaturated ester copolymer (B) graft-modified with α, β-unsaturated carboxylic acid or a derivative thereof is 2 to 50 g / 10 min. Preferably it is 3-20 g / 10min, More preferably, it is 5-15 g / 10min.

  The tackifying resin (C) in the present invention is generally classified into a natural tackifying resin and a synthetic tackifying resin, and the natural systems include gum rosin, tall oil rosin, wood rosin, hydrogenated rosin, disproportionated rosin, and polymerized rosin. Rosin-glycerin ester, rosin-pentaerythritol ester, maleated rosin and hydrides thereof, acid-modified rosin, terpene resin, aromatic-modified terpene resin, terpene phenol resin, hydrogenated terpene resin and the like. A rosin-based tackifying resin is preferably used, and an acid-modified rosin-based tackifying resin is particularly preferably used.

  Synthetic tackifying resins are aliphatic (C5) petroleum resin, aromatic (C9) petroleum resin, copolymer (C5 / C9) petroleum resin, hydrogenated petroleum resin (alicyclic petroleum resin) ), DCPD petroleum resin (alicyclic petroleum resin), pure monomer petroleum resin (styrene, substituted styrene petroleum resin), coumarone-indene resin, alkylphenol resin, xylene resin, and the like. Among these, alicyclic petroleum resins are preferably used.

  The compounding quantity of tackifying resin (C) used for this invention is 10 to 30 weight%. Preferably it is 10-25 weight%, More preferably, it is 15-25 weight%. If it is less than 10% by weight, it is difficult to obtain adhesiveness, and if it is more than 30% by weight, the blocking property is poor.

  Any one of natural tackifying resin and synthetic tackifying resin may be used, or two or more kinds may be used. Preferably, at least one of a natural tackifying resin and a synthetic tackifying resin is used.

  The softening point of the tackifying resin used in the present invention is 80 ° C. or higher and 150 ° C. or lower. Preferably they are 90 degreeC or more and 135 degrees C or less, More preferably, they are 100 degreeC or more and 110 degrees C or less. If it is less than 80 degreeC, it will be easy to block when it is set as a laminated film, and if it is higher than 150 degreeC, it will become what was inferior in low temperature sealing property.

  Various other additives can be used as necessary. For example, coloring agents, blocking agents, and antioxidants. Examples of the colorant include titanium oxide. Examples of the antiblocking agent include silicone, unsaturated fatty acid amides such as erucic acid amide and oleic acid amide, and saturated fatty acid amides such as stearic acid amide and behenic acid amide. Antioxidants include high molecular weight hindered polyphenols, triazine derivatives, high molecular weight hindered phenols, dialkyl phenol sulfides, 2,2-methylene-bis- (4-methyl-6-tert-butylphenol), 4 4-methylene-bis- (2,6-di-tert-butylphenol), 2,6-di-tert-butylphenol-p-cresol, 2,5-di-tert-butylhydroquinone, 2, 2 4-trimethyl-1,2-dihydroquinone, 2,2,4-trimethyl-1,2-dihydroquinone, nickel dibutyldithiocarbamate, 1-oxy-3-methyl-4-isopropylbenzene, 4,4- Butylidenebis- (3-methyl-6-tert-butylphenol), 2-mercaptobenzimidazole.

  The adhesive resin composition of the present invention can be laminated on various polar materials or nonpolar materials and used as an adhesive film. Preferable examples include vapor deposition of metal such as aluminum, metal oxide such as alumina, or inorganic oxide such as silica on a base material on which a metal such as aluminum, such as plastic or film, is laminated. An adhesive film formed by laminating the adhesive resin composition of the present invention on a base material that is used.

The present invention is specifically shown below.
<Creation of graft modified product>
<Synthesis Example 1>
100 parts of EVA resin (trade name: Ultrasen 710, manufactured by Tosoh Corporation, MFR 18 g / 10 min), 5 parts of maleic anhydride, and bis (2-t-butylperoxyisopropyl) benzene (trade name “ Perbutyl P (Nippon Yushi Co., Ltd.) 0.2 part was added and pre-blended for 5 minutes with a Henschel mixer.
The preblend was charged into the hopper and supplied to the extruder using a screw feeder. Unreacted monomer was removed from the vent port by a vacuum pump at a reduced pressure of 760 mmHg.
The obtained extrudate was purified and the unreacted monomer was removed and evaluated. The MFR was 5 g / 10 min and the acid value was 16.
Extruder: Co-rotating twin screw extruder PMT32-40.5 manufactured by IK Corporation
Barrel temperature: 200 ° C (supply port 160 ° C)
Screw rotation speed: 100rpm
Supply speed: 5 kg / hr
MFR was measured according to JIS K 7210 at 190 ° C. under a load of 2160 g. The acid value was measured by the following method. About 1 g of the purified product was precisely weighed and completely dissolved in 100 ml of heated xylene, and then a 0.1 wt% alcoholic phenolphthalein solution was added and titrated with a 0.1 N alcoholic potassium hydroxide solution while hot. The end point of titration was when the red discoloration of phenolphthalein did not disappear for 30 seconds.
<Synthesis Example 2>
The same procedure as in Synthesis Example 1 was conducted except that the EVA resin was changed to an LLDPE resin (trade name: Sumikasen-L FS240, manufactured by Sumitomo Chemical Co., Ltd., MFR 2.2 g / 10 min). The MFR was 1.5 g / 10 min and the acid value was 10.
<Method for creating adhesive resin composition>
The EVA, graft modified product, tackifying resin and various additives shown in Tables 1 and 2 were pre-blended for 5 minutes with a Henschel mixer. A pre-blend product was charged into a hopper and supplied to an extruder using a screw feeder to prepare a resin composition.
Extruder; Co-rotating twin screw extruder PMT32-40.5 manufactured by IK Corporation
Barrel temperature: 140 ° C (supply port 100 ° C)
Screw rotation speed: 100rpm
Supply speed: 5 kg / hr
<Method for creating laminated film>
Using an extrusion laminator, the resin composition was laminated on an aluminum foil (35 μm) with a thickness of 30 μm to prepare a laminated film. Possible to make a laminated film: ○, impossible to make a laminated film: ×. The processing conditions are shown below.
Extrusion laminator: 400M / M test EXT laminator die directly under Musashinokikai Resin temperature: 140-240 ° C. (adjusted appropriately by MFR of resin composition)
Processing speed: 30m / min T die width: 400mm
Cooling roll surface temperature: 15-20 ° C
<Ethylene-unsaturated ester copolymer>
EVA-1: Ultrasen 680 (Tosoh Corporation, vinyl acetate content 20%, MFR 160 g / 10 min)
EVA-2: Evaate CV5053 (manufactured by Sumitomo Chemical Co., Ltd., vinyl acetate content 20%, MFR 70 g / 10 min)
EVA-3: EVAFLEX EV150 (Mitsui / DuPont Polychemical Co., Ltd., vinyl acetate content 33%, MFR 30 g / 10 min)
EVA-4: Ultrasen 539 (Tosoh Corporation, vinyl acetate content 6%, MFR 28 g / 10 min)
EVA-5: Smitate H4021 (manufactured by Sumitomo Chemical Co., Ltd., vinyl acetate content 13%, MFR 20 g / 10 min)
EVA-6: Ultrasen 625 (manufactured by Tosoh Corporation, vinyl acetate content 15%, MFR 14 g / 10 min)
EVA-7: Evaate K2010 (manufactured by Sumitomo Chemical Co., Ltd., vinyl acetate content 25%, MFR 6 g / 10 min)
EVA-8: Ultrasen 515 (manufactured by Tosoh Corporation, vinyl acetate content 6%, MFR 2.5 g / 10 min)
<Graft modified product>
Modified body-1: HPR VR103 (Mitsui / DuPont Polychemical Co., Ltd., maleic anhydride graft EVA, MFR 8 g / 10 min)
Modified body-2: HPR VR105-1 (Mitsui / DuPont Polychemical Co., Ltd., maleic anhydride graft EVA, MFR 15 g / 10 min)
Modified product-3: OREVAC G 18216 (manufactured by Arkema, maleic anhydride graft EVA, MFR 3.5 g / 10 min)
Modified product-4: Graft modified product synthesized in Synthesis Example 1 (MFR 5 g / 10 min)
Modified product-5: Graft modified product synthesized in Synthesis Example 2 (MFR 1.5 g / 10 min)
<Tackifying resin>
TF-1: Alcon P-125 (Arakawa Chemical Industries, alicyclic saturated hydrocarbon resin, softening point 125 ° C.)
TF-2: FTR6100 (manufactured by Mitsui Chemicals, styrene monomer / aliphatic monomer copolymer system, softening point 95 ° C.)
TF-3: Super ester A-100 (Arakawa Chemical Industries, rosin ester, softening point 100 ° C.)
<Additives>
Antioxidant: IRGANOX 1010 (Ciba Specialty Chemicals)
Anti-blocking agent: Incross lip C (manufactured by Croda)
<Measurement method of peel strength>
The laminated film cut to 15 mm width and the aluminum plate, glass plate, HDPE plate and CPP plate were heat sealed at 80 ° C. × 0.3 MPa × 1 second and 120 ° C. × 0.3 MPa × 1 second. After standing for 24 hours, the adhesive strength was measured using a tensile strength tester under conditions of 180 ° angle peeling and a peeling speed of 200 mm / min. 5 N / 15 mm or more: ◯, 2 to 5 N / 15 mm: Δ, 2 N / 15 mm or less: x.
Tensile strength tester: Tensilon RTA-100 manufactured by Orientec
In the present invention, Examples 1 to 5 are reference examples.

Claims (4)

Unsaturated ester content is 3 to 15 wt%, melt flow rate of 10 to 100 g / 10 min ethylene - vinyl acetate copolymer (A) 40 to 80 wt%,
10 to 40% by weight of an ethylene-vinyl acetate copolymer (B) graft-modified with an α, β-unsaturated carboxylic acid or derivative thereof having a melt flow rate of 2 to 50 g / 10 min;
An adhesive resin composition having a melt flow rate of 20 to 100 g / 10 min comprising 10 to 30% by weight of a tackifying resin (C) using a petroleum tackifying resin and a rosin tackifying resin.  The adhesive resin composition according to claim 1, wherein the α, β-unsaturated carboxylic acid is one or more of maleic acid, acrylic acid, methacrylic acid, and itaconic acid.   The ethylene-unsaturated ester copolymer (B) graft-modified with an α, β-unsaturated carboxylic acid or a derivative thereof is a resin grafted in a molten state in the presence of a radical initiator. Item 3. The adhesive resin composition according to Item 1 or 2. Adhesiveness obtained by laminating the adhesive resin composition according to any one of claims 1 to 3 on a base material on which a metal foil is laminated or a base material on which any of metal, metal oxide, and inorganic oxide is deposited. the film.