JP2000238208A - Laminated body and method for manufacturing the same - Google Patents

Abstract

(57) Abstract: (I) A base layer and (II) a printed layer printed on the (I) base layer without using an adhesive for dry lamination or an AC agent for extrusion lamination. And a method for producing the same, which is excellent in the adhesiveness to (II) the printed layer and the (III) resin composition layer extrusion-laminated on the (II) printed layer. SOLUTION: The printing ink is formed by printing using a printing ink in which a printing ink modifier containing (I) a base material layer and (a) a saturated copolymerized polyester and (b) an isocyanate compound is added to an ink base material. The printing ink is applied to a laminate having (II) a printing layer, (A) a polyolefin, and (B) a resin composition layer comprising a resin composition having an epoxy compound, and (I) a base material layer. A method for producing a laminate, wherein (II) a printing layer is formed by printing used, and (II) the resin composition is extrusion-laminated on the printing layer to form a (III) resin composition layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate internally printed with a printing ink and a method for producing the same, and more particularly, to an adhesive property between a base layer and a printed layer printed on the base layer. The present invention also relates to a laminate excellent in adhesion between a printed layer and a resin composition layer extrusion-laminated on the printed layer, and a method for producing the same.

[0002]

2. Description of the Related Art In multilayer laminates used for packaging and the like, internal printing is frequently used except for some coextruded films. Examples of the inner-printed laminate include those having a configuration in which a print layer exists as an intermediate layer of the laminate, such as a transparent base material layer / print layer / adhesive layer / heat seal layer. By thus forming the printed layer on the inner surface of the transparent substrate layer without exposing it on the outer surface of the laminate, a laminate having excellent scratch resistance, scratch resistance, surface gloss and the like can be obtained. However, between the surface of the substrate layer on which the printing ink is printed in a solution state and the printing layer, the printing ink itself is strongly adhered by the adhesiveness of the printing ink itself. The adhesiveness between the heat sealing layer) and the printing layer is low. Therefore, as illustrated in general, an adhesive layer is often provided between the printing layer and the heat sealing layer.

[0003] As a method for producing such a laminate, there are a dry lamination method, an extrusion lamination method, a knee lam lamination method and a solventless lamination method. In particular, the dry laminating method and the neem laminating method mainly apply urethane-based adhesives after diluting them with a dangerous organic solvent, so that they comply with the regulations of the Fire Service Law, deteriorating the working environment, and There were problems such as an increase in the residual solvent. On the other hand, in the extrusion lamination method, an adhesive called an anchor coat agent (hereinafter, referred to as an AC agent) is used.
Since the AC agent has a smaller coating amount than the adhesive used in the dry lamination method, the required organic solvent is also small,
Problems such as compliance with regulations under the Fire Service Law, deterioration of the working environment, and increase in residual solvent in products existed to a greater or lesser extent as with the dry lamination method. In addition, the intermediate layer of the laminate needs to be coated with an AC agent on both sides in some cases, so that there is a problem that the number of steps increases. Furthermore, the coating on the thick thing, the scattering of the AC agent,
There was also a problem that it was easy to lead to troubles such as behind-the-scenes.

[0004] Each of these methods has a common problem of using a solvent. To solve this problem, attempts have been made to use no solvent or reduce the amount used. The solvent-free lamination method is a method that fundamentally improves on these disadvantages, and does not require an organic solvent to apply an adhesive that has been heated to a molten state. However, there is a problem that the viscosity of the adhesive to be applied is higher than that of the solvent type, and troubles such as uneven coating are likely to occur. Further, since the molecular weight is small, there are also problems such as occurrence of adhesion trouble due to insufficient curing and insufficient heat resistance.

In the extrusion lamination method, it is known that an ethylene- (meth) acrylic acid copolymer obtained by copolymerizing an acid component is used to firmly adhere to an aluminum foil without using an AC agent. . Also, Japanese Patent Application Laid-Open
JP-A-51690 discloses a method in which a modified PP obtained by graft-modifying an unsaturated carboxylic acid to polypropylene (hereinafter referred to as PP) is extrusion-laminated to a base material layer, and heat-treated later to improve the adhesive strength. ing. However, the substrates that can be adhered by any of the methods are limited to Al foil and some of the vapor-deposited substrates, and the adhesion to the printing ink remains insufficient.

[0006] Japanese Patent Application Laid-Open No. 7-314629 discloses that a plastic substrate is subjected to a surface oxidation treatment under specific conditions, and a molten resin surface is subjected to an ozone treatment at the time of extrusion lamination, thereby providing a strong adhesive strength without an AC agent. A method of obtaining is disclosed. However, in this method, it is necessary to spray ozone on the resin, and it is necessary to consider the odor and toxicity of ozone, and there is a problem that the equipment cost is high. JP-A-8-188679 discloses that the molecular weight is 30.
There is disclosed a method of obtaining a strong adhesive strength to various substrates by extrusion laminating a resin composition containing an epoxy compound of 00 or less. However, this method has a disadvantage that the adhesive strength between the substrate layer and the printing layer formed by general gravure printing is weak.

Two-pack inks have been developed as printing inks having improved adhesion to substrates, particularly printing inks having improved adhesion in applications exposed to high-temperature and high-humidity environments such as retorts. This is to improve the adhesiveness by using a curing agent together when the adhesiveness is insufficient with ordinary printing inks. In this method, an isocyanate-based curing agent is generally used as a curing agent, and the effect of increasing the film strength of the printing ink itself and improving the adhesiveness between the base material layer and the printing layer can be obtained by the curing reaction of the isocyanate. However, since the curing reaction of the isocyanate is usually completed after printing and before lamination, there is no effect on improving the adhesiveness between the layer to be extruded and the printed layer.

[0008]

DISCLOSURE OF THE INVENTION The present invention overcomes the above problems and provides a substrate layer and a print printed on the substrate layer without using an adhesive for dry lamination or an AC agent for extrusion lamination. It is an object of the present invention to provide a laminate excellent in adhesiveness with a layer and adhesiveness between a printed layer and a resin composition layer extrusion-laminated on the printed layer, and a method for producing the same.

[0009]

Means for Solving the Problems The present inventors have made intensive studies in view of the above problems, and as a result, have found that ordinary solvent-based printing inks
A polyolefin containing an epoxy compound is added to a resin composition layer (extruded laminate layer) by adding an ink modifier comprising a saturated copolymerized polyester having a molecular weight of 5,000 to 50,000 and a melting point of 200 ° C. or less and an isocyanate compound. As a result, the present inventors have found that the above-mentioned problems can be solved, leading to the present invention.

That is, the laminate of the present invention is a laminate having (I) a base material layer, (II) a printing layer, and (III) a resin composition layer, wherein (II) the printing layer is ( a) 500 molecular weight
(I) Base layer by printing using a printing ink in which a printing ink modifier containing a saturated copolymerized polyester having a melting point of 0 to 50000 and a melting point of 200 ° C. or less and (b) an isocyanate compound is added to an ink base material. (III) The resin composition layer comprises (A) a polyolefin having a melt flow rate of 0.1 to 100 g / 10 min, and (B) two or more epoxy groups in the molecule. An epoxy compound having a molecular weight of 3000 or less, and a resin composition comprising (A) 0.01 to 5 parts by weight of an epoxy compound per 100 parts by weight of a polyolefin. And (II) the surface of the printing layer is in contact with the (III) resin composition layer.

The resin composition further comprises (C) an olefin resin having a functional group capable of reacting with an epoxy group, and (A) a polyolefin and (C) a functional group capable of reacting with an epoxy group. The ratio of the olefin resin having a functional group capable of reacting with the epoxy group to the resin component composed of the olefin resin is less than 30% by weight, and the epoxy compound (B) to 100 parts by weight of the resin component. Is preferably added in an amount of 0.01 to 5 parts by weight. The epoxy compound (B) is preferably an epoxidized vegetable oil.

The (C) olefin resin having a functional group capable of reacting with an epoxy group has at least one group selected from the group consisting of an acid anhydride group, a carboxyl group and a metal carboxylate. It is desirable to use an olefin-based copolymer or a modified olefin resin contained therein. The (C) olefin resin having a functional group capable of reacting with an epoxy group is preferably an ethylene-maleic anhydride copolymer or an ethylene-maleic anhydride- (meth) acrylate copolymer. . Further, it is desirable that the (I) base material layer is made of polyester.

[0013] The method for producing a laminate according to the present invention comprises:
(I) At least one surface of the base material layer has (a) a molecular weight of 50
(II) a printing layer is formed by printing using a printing ink to which an ink modifier containing a saturated copolymerized polyester having a melting point of 200 to 50,000 and a melting point of 200 ° C. or less and (b) an isocyanate compound is added; On this (II) printing layer, the melt flow rate (A) is 0.1 to 100 g /
(A) polyolefin 1 having a polyolefin of 10 minutes and (B) an epoxy compound containing two or more epoxy groups in the molecule and having a molecular weight of 3000 or less.
(B) 0.01 to 100 parts by weight of the epoxy compound
(III) A resin composition layer comprising a resin composition added in an amount of 5 parts by weight is laminated by an extrusion lamination method without using an anchor coating agent.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The (a) saturated copolyester in the printing ink modifier according to the present invention is defined as having a degree of crystallinity of two or more dicarboxylic acid components and / or diol components that do not contain unsaturated groups in the molecule. , A polyester having a controlled melting point, which is different from a normal homopolyester comprising one type each of a dicarboxylic acid component and a diol component.

(A) The molecular weight of the saturated copolyester is 5,000 to 50,000, preferably 10,000 to 3,000.
0000. If the molecular weight is less than 5,000, sufficient adhesive strength cannot be obtained, and if the molecular weight exceeds 50,000, the solution viscosity is high and the printability is poor, which is not preferable. (A) The melting point of the saturated copolymerized polyester is 200 ° C. or lower, preferably 150 ° C. or lower. Some saturated copolymer polyesters having a high copolymerization ratio have reduced crystallinity and their melting points are not measured. However, such saturated copolymer polyesters can also be suitably used in the present invention. Those having a melting point exceeding 200 ° C. are not preferred because of poor solubility in solvents.

(A) As a raw material monomer for a saturated copolymerized polyester, a general raw material monomer for a polyester can be used as it is. However, in order to leave no unsaturated group in the obtained polyester, a polyester containing no unsaturated group should be used. Must be used. Examples of the dicarboxylic acid component include terephthalic acid, adipic acid, isophthalic acid, 1,6-naphthalenedicarboxylic acid, phthalic acid, phthalic anhydride, tetrahydrophthalic anhydride, sebacic acid, and tetrachlorophthalic anhydride. As the diol component, ethylene glycol, diethylene glycol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol, propylene glycol, dipropylene glycol, trimethylolpropane monoallyl ether, bisphenoldioxypropyl ether , Polybutadiene glycol, hydrogenated polybutadiene glycol, hydrogenated bisphenol A, and the like.

(A) In the saturated copolymerized polyester,
The dicarboxylic acid component and the diol component are essential, and the crystallinity and the melting point are reduced by using two or more dicarboxylic acid components and / or diol components,
It achieves solubility in solvents and adhesion to substrates. (A) The saturated copolymerized polyester copolymer can be obtained by direct polymerization of these raw material monomers, and other polyester polymerization methods used industrially such as an ester exchange method using an ester corresponding to a dicarboxylic acid component Any of them can be suitably used.

The amount of the (a) saturated copolymerized polyester is not particularly limited, but is preferably 1 to 30 parts by weight, more preferably 5 to 20 parts by weight, based on 100 parts by weight of the ink base material. . If the amount is less than 1 part by weight, it is not possible to obtain a high adhesiveness to a specific resin composition, which is an effect of the present invention. If the amount is more than 30 parts by weight, the fluidity of the printing ink deteriorates, printing becomes difficult, and high adhesiveness to a specific resin composition, which is an effect of the present invention, cannot be obtained. (A) The saturated copolyester is usually solid at room temperature and must be dissolved in a solvent when printing. However, generally, the polyester is dissolved in a solvent in advance and then mixed with a solvent-based printing ink. Is desirable.

(B) in the printing ink modifier according to the present invention
An isocyanate compound is a compound having two or more isocyanate groups in a molecule. (B) Examples of the isocyanate compound include 2,4-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, dianisidine diisocyanate, triden diisocyanate, hexamethylene diisocyanate, metaxylylene diisocyanate, phenyl isocyanate, and 1,5-naphthalenediisocyanate. Further, those obtained by increasing the number of isocyanate groups by using these as dimers or trimers are also preferably used.

(B) The compounding amount of the isocyanate compound is
Although not particularly limited, it is preferably 0.01 to 5 parts by weight, more preferably 0.1 to 2 parts by weight, based on 100 parts by weight of the ink base material. If the amount is less than 0.01 part by weight, it is not possible to obtain a high adhesiveness to a specific resin composition, which is an effect of the present invention. If the amount is more than 5 parts by weight, the fluidity of the ink deteriorates, printing becomes difficult, and the durability of the printed film becomes insufficient. It is desirable that the isocyanate compound (b) is supplied in a separate container from the ink base agent and the saturated copolymerized polyester (a), and is used by mixing at a predetermined ratio immediately before printing. The (a) saturated copolymerized polyester may be mixed with the ink base in advance, or may be supplied in a separate container and mixed at a predetermined ratio immediately before printing.

The printing ink according to the present invention is obtained by adding the above-mentioned printing ink modifier to an ink base material. The ink base material used in the present invention is, if necessary, a coloring material that develops a color as an ink, a vehicle that holds the entire ink, a solvent that lowers ink viscosity and makes printing easier,
It contains various additives that enhance printability. As such an ink base, for example, a commercially available ordinary solvent-based printing ink or the like can be used. If necessary, an ink base containing no coloring material may be used.

As the coloring material, dyes and pigments are preferably used. Among them, organic pigments such as insoluble azo and azo lake, and inorganic pigments such as titanium dioxide, carbon black, cadmium red and chrome yellow are preferably used. . The amount of the coloring material is not particularly limited, for example,
It is in the range of 0.1 to 20 parts by weight based on 100 parts by weight of the ink base material. As the vehicle, natural resins such as rosin,
Synthetic resins such as rosin-modified maleic acid resin, nitrified cotton, polyurethane resin, polyester resin, chlorinated polypropylene resin, and vinyl chloride-vinyl acetate copolymer resin are preferably used.

The printing ink according to the present invention is provided with waxes, plasticizers, antioxidants, surfactants, defoamers, thickeners, antiblocking agents, in order to impart necessary properties as printing inks. An antistatic agent, a filler, a solvent, and the like are appropriately added as needed. Further, the printing ink according to the present invention,
It can be used after diluting to the required concentration by adding a solvent. As the solvent in this case, the solvent used for diluting the printing ink is usually used as it is, and in particular, a solvent that dissolves (a) the saturated copolymerized polyester is preferable. As the solvent, toluene, methyl ethyl ketone, dichloromethane,
Examples thereof include 1,2-dichloroethane, trichloroethylene, and ethyl acetate, but are not limited thereto.

The material of the substrate layer (I) of the laminate of the present invention may be any material which is usually used as the substrate of the laminate, for example, polyamide 6, polyamide 66,
Polyamide (nylon) such as polyamide 6, 66 and polyamide 12; polyethylene terephthalate (hereinafter referred to as PE
T), polybutylene terephthalate (hereinafter PBT)
Polyester) such as polyethylene naphthalate (hereinafter referred to as PEN); saponified ethylene-vinyl acetate copolymer (hereinafter referred to as EVOH), branched low-density polyethylene (hereinafter referred to as LDPE), linear low-density polyethylene (Hereinafter referred to as LLDPE), medium / high density polyethylene (hereinafter referred to as HDPE), propylene-based polymer, ethylene- (meth) acrylate copolymer (hereinafter referred to as E (M)
A), thermoplastic resins such as polycarbonate (hereinafter referred to as PC), polyacrylonitrile (hereinafter referred to as PAN); metal foils such as aluminum (hereinafter referred to as Al), iron, copper, magnesium, and tin; Paper bases such as paper, coated paper, kraft paper, tissue paper and the like can be mentioned. Among them, polyester and EVOH are particularly preferred.

The base layer (I) of the laminate of the present invention has been subjected to a vapor deposition treatment of Al, Al oxide, silicon oxide, etc., a coating treatment of polyvinylidene chloride or the like according to various uses. You may. Further, the shape may be a woven fabric or a non-woven fabric. Further, uniaxial or biaxial stretching may be performed. Further, another layer may be laminated on the surface opposite to the surface to be printed. Further, in order to improve the printability, those which have been subjected to a surface treatment such as a corona treatment, a flame treatment, an ultraviolet irradiation treatment, an electron beam irradiation treatment and a low-temperature plasma treatment in advance are more preferably used.

The (II) printing layer of the laminate of the present invention is a layer formed by printing on at least one surface of the above-mentioned (I) base material layer using the printing ink according to the present invention. The printed layer (II) of the laminate of the present invention may be subjected to a surface treatment such as a corona treatment, a flame treatment, an ultraviolet irradiation treatment, an electron beam irradiation treatment, and a low-temperature plasma treatment in order to improve the adhesiveness.

The (III) resin composition layer of the laminate of the present invention comprises:
From a resin composition comprising (A) a polyolefin having a melt flow rate of 0.1 to 100 g / 10 min and (B) an epoxy compound having two or more epoxy groups in the molecule and having a molecular weight of 3000 or less. Layer. (A) As polyolefin, LDPE, LLDP
E or ethylene such as HDPE or ethylene and carbon number 3
To 16-α-olefin homo- or copolymers, propylene-based polymers, ethylene-vinyl acetate copolymers (hereinafter E
VA), E (M) A, etc., and among them, LDPE, which is frequently used as a packaging material, is particularly preferable.

LDPE is generally obtained by polymerizing under a high pressure of 1000 to 3500 atm in the presence of a free radical generator such as a peroxide, and is characterized by having many long-chain branches. . It is known that it has excellent extrusion characteristics due to its structure having long-chain branches, and is particularly suitably used for extrusion lamination. The reactor used for the polymerization at this time may be either an autoclave type or a tubular type. EVA and E (M) A are obtained by polymerization in the presence of a free radical generator such as a peroxide, similarly to LDPE.

HDPE and LLDPE can be obtained by homopolymerizing ethylene using a catalyst generally called a Ziegler catalyst, a Phillips catalyst, or a metallocene catalyst, or by copolymerizing ethylene with an α-olefin having 3 to 16 carbon atoms. . These can be generally produced by any of low-pressure, medium-pressure, and high-pressure methods, and are produced by any of a gas phase method, a solution method, and a slurry method. Examples of the propylene-based polymer include a propylene homopolymer, an ethylene-propylene copolymer, and a random or block copolymer with an α-olefin having 4 to 16 carbon atoms.

(A) The MFR of the polyolefin is 0.1
-100 g / 10 min is preferable, and 1-20 g / 10 min is particularly preferable in terms of moldability. MFR is 0.1g / 10
If it is less than 100 minutes, the moldability is poor, and if it exceeds 100 g / 10 minutes, the mechanical strength is poor. Here, the MFR is a value measured at 190 ° C. (based on JIS K6760) for an ethylene-based resin and 230 ° C. (based on JIS K6758) for a polypropylene-based resin.

The (B) epoxy compound of the resin composition layer (III) of the laminate of the present invention refers to an epoxy compound having at least two or more epoxy groups (oxirane groups) in the molecule and having a molecular weight of 300.
It is a polyvalent epoxy compound of 0 or less. (B) The epoxy compound needs to contain two or more epoxy groups in the molecule, and when there is one epoxy group in the molecule, the object of the present invention is (II) the printing layer and (III) Adhesive strength with the resin composition layer cannot be sufficiently obtained. (B) The molecular weight of the epoxy compound must be 3000 or less, and particularly preferably 1500 or less. Molecular weight 3
If it exceeds 000, sufficient adhesive strength cannot be obtained when the composition is formed.

(B) Epoxy compounds include diglycidyl phthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl adipic ester, trimethylolpropane triglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol Examples include polyglycidyl ether, butanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, phenol novolak polyglycidyl ether, and epoxidized vegetable oil. Among them, epoxidized vegetable oil is preferred from the viewpoint of ease of handling and safety when used for food packaging materials.

The epoxidized vegetable oil is obtained by epoxidizing an unsaturated double bond of natural vegetable oil using a peracid or the like. Epoxidized soybean oil, epoxidized linseed oil, epoxidized olive oil, epoxidized sap oil Flower oil, epoxidized corn oil and the like can be mentioned. These epoxidized vegetable oils are, for example, O-13 manufactured by Asahi Denka Kogyo KK
It is commercially available as 0P (epoxidized soybean oil), O-180A (epoxidized linseed oil) and the like. It should be noted that the presence of non-epoxidized or insufficiently epoxidized oil, which is by-produced when epoxidizing vegetable oil, does not hinder the spirit and essence of the present invention.

The amount of the epoxy compound (B) is (A)
It is 0.01 to 5 parts by weight, preferably 0.01 to 0.9 parts by weight, based on 100 parts by weight of the polyolefin.
When the amount of the epoxy compound (B) is less than 0.01 part by weight, the adhesion strength to the printing layer (II) is insufficient. When the amount exceeds 5 parts by weight, the adhesion strength is improved, but the laminate is sticky. Problems such as blocking and odor occur.

The resin composition used for the resin composition layer (III) of the laminate of the present invention preferably further contains (C) an olefin resin having a functional group capable of reacting with an epoxy group. (C) The olefin-based resin having a functional group capable of reacting with an epoxy group is not an essential component, but by adding it, (II) the adhesiveness to the print layer can be further improved. Examples of the functional group that reacts with the epoxy group include a carboxyl group or a derivative thereof, an amino group, a phenol group, a hydroxyl group, and a thiol group. Among them, an acid anhydride group, a carboxyl group and a metal salt of a carboxylic acid are preferable from the balance between reactivity and stability.

As a method for introducing a functional group which reacts with an epoxy group into an olefin-based resin, a copolymerization method and a grafting method are mainly used. Manufactured by a copolymerization method,
Examples of the olefin copolymer having a functional group that reacts with the epoxy group include a multi-component copolymer of ethylene and a compound capable of reacting with ethylene.

Compounds capable of reacting with ethylene used for copolymerization include α, β-unsaturated carboxylic acids such as (meth) acrylic acid; and α, β-unsaturated carboxylic acids such as sodium (meth) acrylate.
Unsaturated carboxylic acid metal salts; unsaturated carboxylic anhydrides such as maleic anhydride, itaconic anhydride and citraconic anhydride;
Examples include hydroxyl group-containing compounds such as hydroxyethyl (meth) acrylate and (meth) allyl alcohol; and unsaturated amino compounds such as allylamine, but are not limited thereto. Among them, those having an acid anhydride group, a carboxyl group and a metal salt of a carboxylic acid are preferred. Further, in addition to these unsaturated compounds, a vinyl alcohol ester such as (meth) acrylate, vinyl acetate, vinyl propionate and the like may be copolymerized and used. These compounds can be used as a mixture of two or more kinds in a copolymer with ethylene, and a copolymer of these compounds and ethylene can be used in combination of two or more kinds.

As the olefin copolymer having a functional group which reacts with an epoxy group, produced by a copolymerization method, an ethylene-maleic anhydride copolymer or an ethylene-maleic anhydride- (meth) acrylate ester copolymer can be used. Polymers are preferably used.

A modified olefin resin having a functional group capable of reacting with an epoxy group introduced by graft modification acts on a polyolefin in the presence of a free radical generator such as a peroxide by melting or modifying the unsaturated compound for modification in a molten state. It is common to manufacture it. Examples of polyolefins for graft modification include LDPE, LLDPE, HDPE, PP, ethylene-propylene copolymer, propylene-butene-1 copolymer, EVA, E (M) A, ethylene-vinyl acetate- (meta- ) Acrylate copolymers and the like, and these can be used alone or in combination of two or more. Further, a copolymer obtained by further graft-modifying a copolymer containing an acid or a derivative thereof, such as an ethylene- (meth) acrylate-maleic anhydride copolymer, may be used.

The type of free radical generator used at the time of graft modification is not particularly limited, but a common organic peroxide is used. Among them, dicumyl peroxide, 2,2 5-dimethyl-2,5
Specific examples thereof include -bis (t-butylperoxy) hexane, 1,3-bis (2-t-butylperoxyisopropyl) benzene, and benzoyl peroxide.

As the unsaturated compound for modification, the same unsaturated compound as the above-mentioned compound copolymerizable with ethylene is used, and a carboxylic acid group or a carboxylic acid anhydride group and its metal salt, amino group, hydroxyl group and the like are used. Basically, it can be used as long as it has a radically reactive unsaturated group. Examples of unsaturated compounds for modification include α, β-unsaturated carboxylic acids such as (meth) acrylic acid; metal salts of α, β-unsaturated carboxylic acids such as sodium (meth) acrylate; maleic anhydride, itaconic anhydride Acids, unsaturated carboxylic anhydrides such as citraconic anhydride; hydroxyl-containing compounds such as hydroxyethyl (meth) acrylate and (meth) allyl alcohol;
Examples thereof include amino compounds such as allylamine, but are not limited thereto. Among them, those having an acid anhydride group, a carboxyl group and a metal salt of a carboxylic acid are preferred.

The amount of the olefin resin (C) having a functional group capable of reacting with an epoxy group is generally selected from the resin component consisting of (A) a polyolefin and (C) an olefin resin having a functional group capable of reacting with an epoxy group. 3 for
It is less than 0% by weight, preferably 2 to 25% by weight, more preferably 5 to 20% by weight. 30% by weight
Although the above addition has the effect of improving the adhesiveness, it is not economical. The amount of the epoxy compound (B) to be added is 0.01 to 5 parts by weight, preferably 0.01 to 0.9 parts by weight, based on 100 parts by weight of the resin composition.
When the amount of the epoxy compound (B) is less than 0.01 part by weight, the adhesion strength to the printing layer (II) is insufficient. When the amount exceeds 5 parts by weight, the adhesion strength is improved, but the laminate is sticky. Problems such as blocking and odor occur.

Furthermore, (III) a resin composition layer may optionally contain conventional additives such as an antioxidant, a plasticizer, a lubricant,
Various stabilizers, antiblocking agents, antistatic agents, pigments,
Various inorganic and organic fillers may be added.
(III) To obtain the resin composition used for the resin composition layer, the above-mentioned (A) polyolefin, (B) an epoxy compound and (C) an olefin resin having a functional group capable of reacting with an epoxy group are mixed with a Henschel mixer. A method of mixing with a ribbon mixer or the like, and a method of kneading the mixed material with an open roll, a Banbury mixer, a kneader, an extruder, or the like may be appropriately used. The kneading temperature is usually from the melting point of the resin to 350 ° C., preferably 120 to 300 ° C. for a polyethylene resin, and 170 to 300 ° C. for a polypropylene resin.

The laminate of the present invention comprises (I) a base material layer, (II)
It is necessary that the printing layer and the (III) resin composition layer are sequentially laminated. Further, another layer may be further laminated outside the (I) base material layer or the (III) resin composition layer. That is, (I) base layer / (II) printing layer / (III) resin composition layer is fundamental, but (I) base layer / (I
I) printing layer / (III) resin composition layer / LLDPE layer,
(I) substrate layer / (II) printing layer / (III) resin composition layer / A
1 layer / AC agent layer / LDPE layer, (I) substrate layer / (II) printing layer / (III) resin composition layer / Al evaporated PET layer / (III)
Resin composition layer, (I) substrate layer / (II) printing layer / (III) resin composition layer / Al deposited PET layer / AC agent layer / LDPE
Layer, (I) substrate layer / (II) printing layer / (III) resin composition layer / silica-deposited PET layer / (III) resin composition layer, (I) substrate layer / (II) printing layer / ( III) resin composition layer / silica-deposited PET layer / AC agent layer / LDPE layer, (III) resin composition layer / (II) printing layer / (I) substrate layer / LDPE layer / Al layer /
AC agent layer / LDPE layer, (III) resin composition layer / (II) printing layer / (I) substrate layer / ethylene- (meth) acrylic acid copolymer (hereinafter E (M) AA) layer / Al layer / AC agent layer / LD
PE layer, (III) resin composition layer / (II) printing layer / (I) substrate layer / LDPE layer / Al layer / E (M) AA layer, (III) resin composition layer / (II) printing layer / (I) substrate layer / paperboard layer / LD
PE layer / Al layer / AC agent layer / LDPE layer, (III) resin composition layer / (II) printing layer / (I) substrate layer / paperboard layer / LDP
Examples include an E layer / Al layer / E (M) AA layer / LDPE layer, but are not limited thereto.

Next, a method for producing a laminate of the present invention will be described. The laminate of the present invention comprises (I) forming a (II) printing layer on at least one side of a base material layer by printing using the printing ink according to the present invention, and then forming the (II) printing resin on the printing layer. It is manufactured by a method of laminating a resin composition layer (III) composed of a composition by an extrusion lamination method without using an anchor coating agent.

By printing (I) on the surface of the substrate layer (II)
Various known printing methods can be used to form the printing layer. That is, gravure printing, screen printing, offset printing, flexographic printing, letterpress printing, and the like are preferably used, and gravure printing is particularly preferably used, but is not limited thereto. The printing may be a single color or a multi-color printing, or may be a solid printing of the entire surface or a partial printing with a blank portion left. (II) The resin composition layer can be directly laminated on the printing layer by the extrusion lamination method described below, but corona treatment, flame treatment, infrared irradiation treatment, electron beam irradiation treatment, low-temperature plasma treatment, etc. Surface treatment may be performed.

As a method for laminating the (III) resin composition layer on the (II) printing layer, an extrusion lamination method is used.
This is a method of continuously forming and bonding a molten resin film extruded from a T-die onto a (II) printed layer by pressing and bonding at the same time. The molten resin extruded from the T-die is guided between two cooling rolls and a pressure roll together with the base material composed of the base layer (I) and the printing layer (II), and is pressed and laminated. Cooled.

In the case of polyethylene resin, the molding temperature at the time of extrusion lamination is generally 200 to 400 ° C., preferably 240 to 370 ° C., and more preferably 280 to 340 ° C. Ozone treatment as required,
Oxygen treatment, corona treatment, flame treatment, ultraviolet irradiation treatment, electron beam irradiation treatment, low-temperature plasma treatment and the like may be used in combination. If the molding temperature is 200 ° C. or lower, sufficient adhesive strength cannot be obtained, and if the molding temperature is 400 ° C. or higher, the moldability deteriorates, and the product properties such as odor and heat sealability of the obtained laminate deteriorate. Similarly, the molding temperature of the polypropylene resin is generally 170 ° C. or higher, preferably 200 to 350 ° C., and more preferably 240 to 320 ° C.

When laminating the (III) resin composition layer on the (II) printed layer by the extrusion lamination method, a sandwich lamination method in which another layer is inserted from the cooling roll side, and two or more resins are simultaneously extruded. Lamination of three or more layers may be performed by a method such as a coextrusion lamination method. However, when laminating by the coextrusion laminating method, it is necessary to use the (III) resin composition layer for the layer in contact with the (II) printing layer.

In the laminate of the present invention and the method for producing the same, a printing ink obtained by adding a printing ink modifier containing (a) a saturated copolymerized polyester and (b) an isocyanate compound to an ink base material is used. Further, since a resin composition containing (A) a polyolefin and (B) an epoxy compound is used for the (III) resin composition layer, adhesion between the (II) printing layer and the (III) resin composition layer The performance is improved. Further, since the isocyanate compound is used, the adhesiveness between the (I) base material layer and the (II) printing layer is also improved.

Although the reason for the improvement in adhesion is not necessarily clear, (A) is used in the resin composition layer (A).
When the polyolefin is extruded from the extruder or from a T-die or the like, it is oxidized by air in contact with air, and in the process of oxidation, a reaction between the polyolefin (A) and the epoxy compound (B) occurs, and the epoxy compound (B) Is grafted onto the polyolefin (A), and the unreacted epoxy group remaining in the molecule of the grafted epoxy compound (B) is contained in the printing layer (II). Is presumed to be able to react with the (II) printing layer and the (III) resin composition layer. further,
The fact that a sufficient adhesive strength is exhibited by the reaction of (b) the isocyanate compound with (I) the base layer is presumed to be the reason that a strong interlayer adhesive strength specific to the printing ink according to the present invention is obtained.

Usually, the epoxy compound (B) is used as a stabilizer or a plasticizer for polymers such as polyvinyl chloride, or added to a resin containing a carboxylic acid group or a carboxylic acid derivative group in the molecule. A technique used as a cross-linking agent is also disclosed (JP-A-60-112815). In addition, JP-A-8-188679 discloses that by mixing an epoxy compound with a polyolefin,
It is disclosed that it can be firmly bonded to polyester or the like. However, the addition of the epoxy compound alone does not provide sufficient adhesive strength to the print layer.
In addition, there is no disclosure of saturated copolymer polyesters having a low melting point which can be blended in printing inks, and sufficient interlayer adhesive strength cannot be obtained even when these saturated polyesters are coated on a substrate surface.

[0053]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

The production of the laminate and the measurement of the physical properties of the laminate in the examples and comparative examples were carried out according to the following methods. (1) Resin composition The following (A) polyolefin, (B) epoxy compound,
(C) an olefin resin having a functional group capable of reacting with an epoxy group (hereinafter referred to as component (A), component (B),
(C) The components were dry-blended using a Henschel mixer at the compounding amounts shown in Table 1 and then Φ30.
The resulting mixture was melt-kneaded using a twin-screw extruder to obtain pellets of the desired resin composition.

(A) Component A-1: LDPE (MFR 4.0 g / 10 min, density 0.
A-2: LDPE (MFR: 9.0 g / 10 min, density: 0,1 g / cm ³ )
917 g / cm ³ ) (B) Component B-1: Epoxidized soybean oil (O-Made, Asahi Denka Kogyo KK)
130P) B-2: Epoxidized linseed oil (Osahi Denka Kogyo KK, O
-180A) (C) component C-1: ethylene-maleic anhydride copolymer (maleic anhydride content: 1.5% by weight, MFR: 9.2 g / 10 minutes)

(2) Production of Laminate A pellet of the above resin composition is extruded into an extrusion laminating machine equipped with an extruder having a diameter of 90 mm (manufactured by Modern Machinery Co., Ltd.).
Using a distance of 120m from the T die to the nip roll
at a lamination speed of 100 m / min to produce a laminate. At this time, corona discharge treatment was performed at a predetermined discharge density using a corona discharge treatment device (manufactured by Pillar Co., Ltd.) as necessary.

(3) Measurement of Adhesive Strength The laminate obtained by the above-described process was placed 15 m in the flow direction.
The sheet was cut into strips having a width of m, and the peeling strength at T peeling was measured at a peeling speed of 300 mm / min. When (II) the printing layer remains on the (I) base material layer side, "peeling between ink and resin"
(II) When the printing layer is peeled off from the (I) base material layer together with the (III) resin composition layer, "peeling between base material and ink", (II)
When the printing layer remained on both sides of the (I) base material layer side and the (III) resin composition layer side, it was regarded as "ink cohesion failure", and the result was described as such.

[Example 1] An ink base containing MAS322 as a coloring material, X322LPR61 manufactured by Toyo Ink Mfg. Co., Ltd.
Using S white, 100 parts by weight of this ink base material, as a (a) saturated copolymerized polyester (hereinafter, referred to as component (a)), Byron RV-24SS manufactured by Toyobo Co., Ltd. (solid content 30% by weight, solvent content 70% by weight) ), 18 parts by weight of (b) an isocyanate compound (hereinafter referred to as component (b)), 2 parts by weight of Coronate L manufactured by Nippon Polyurethane Industry Co., Ltd., and the mixture is stirred for 10 minutes. On the other hand, 100 parts by weight of ethyl acetate was added as a diluent to adjust the solution viscosity. Using the printing ink thus prepared, a 100 μm thick biaxially stretched P
Printing was performed on the corona-treated surface of the ET film ((I) base material layer) with a constant thickness coating machine so as to have a wet coating thickness of 10 μm. This was dried for 1 minute in a gear oven at 80 ° C. to form (II) a printed layer.

(III) As the resin composition of the resin composition layer,
0.9 parts by weight of epoxidized soybean oil (B-1) was added to 100 parts by weight of LDPE (A-2), and the mixture was kneaded and pelletized using a φ30 mm twin-screw extruder.
(II) In-line output 7 kW, electrode width 60 on the printed layer
While performing a corona discharge treatment at 0 mm, an LLDPE film having a thickness of 60 μm was used as a sand substrate, and the resin composition of the (III) resin composition layer was formed on the (II) printing layer at a temperature of 320 ° C.
Extrusion sand lamination at 20 ° C., thickness 20 μm, (I)
Base layer / (II) printing layer / (III) resin composition layer / LLDP
A laminate comprising an E film layer was obtained. The adhesive strength of this laminate was measured. Table 1 shows the results. A laminate having excellent interlayer adhesion was obtained.

Example 2 As the component (b) in the printing ink, RT-80 manufactured by Toyo Morton Co., Ltd. was used, and (III) epoxidized soybean oil (B-) in the resin composition for the resin composition layer was used.
Example 1 was repeated except that 1) was changed to 0.1 parts by weight. Table 1 shows the results. A laminate having excellent interlayer adhesion was obtained.

[0061] [Example 3] The ink base material in the printing ink, of Toyo Ink Mfg. Co., Ltd. containing TiO ₂ as a colorant N
Example 1 was changed to ewMax630NS white, and (I) a 6-nylon biaxially stretched film (Harden N1100, 15 μm thick) manufactured by Toyobo was used as the base layer.
The same was done. Table 1 shows the results. (I) A laminate having excellent interlayer adhesion could be obtained even when nylon was used for the substrate layer.

[Example 4] (III) Component (B) in the resin composition for the resin composition layer was replaced with epoxidized linseed oil (B-2).
The procedure was performed in the same manner as in Example 1 except for changing to. Table 1 shows the results
Shown in As in Example 1, a laminate having excellent interlayer adhesion was obtained.

Example 5 (III) As a resin composition for a resin composition layer, 85 parts by weight of LDPE (A-1), 0.8 parts by weight of epoxidized soybean oil (B-1), ethylene-anhydrous The procedure was performed in the same manner as in Example 1 except that 15 parts by weight of the maleic acid copolymer (C-1) was kneaded and pelletized. Table 1 shows the results. By adding the component (C), the adhesiveness to the printing layer (II) was further improved.

Example 6 As the component (a) in the printing ink, 13.5 parts by weight of Chemit KS-903 manufactured by Toray (solid content: 30% by weight, solvent: 70% by weight), and as the component (b), Example 1 was repeated except that 1.15 parts by weight of Toyo Morton's RT-80 was used. Table 1 shows the results. A laminate having excellent interlayer adhesion was obtained.

[Comparative Example 1] The same procedure as in Example 1 was carried out except that the component (b) Coronate L was not added to the printing ink. Table 1 shows the results. The adhesion between (I) the base layer and the (II) print layer was poor, and in the peel test, the (II) print layer was separated from the (I) base layer.

Comparative Example 2 The same procedure as in Example 1 was carried out except that the component (a) was not added to the printing ink. Table 1 shows the results
Shown in The adhesion between the (II) printing layer and the (III) resin composition layer was insufficient.

Comparative Example 3 (III) As a resin composition for a resin composition layer, 85 parts by weight of LDPE (A-1) and 15 parts by weight of an ethylene-maleic anhydride copolymer (C-1) were kneaded. The procedure was performed in the same manner as in Example 1 except that pelletized material was used. Table 1 shows the results. When component (C) is added without adding epoxy compound (B), (II)
The adhesion between the printing layer and the (III) resin composition layer was insufficient.

[Comparative Example 4] The same operation as in Example 1 was carried out except that the component (a), Byron RV-24SS, was used without using the ink base and the component (b) as the printing ink. Table 1 shows the results. The adhesion between the (II) printing layer and the (III) resin composition layer was insufficient.

[0069]

[Table 1]

[0070]

As described above, according to the laminate of the present invention, the printed layer (II) has (a) a molecular weight of 5,000 to 500.
(I) at least the base layer by printing using a printing ink in which a printing ink modifier containing a saturated copolymerized polyester having a melting point of 200 ° C. or less and (b) an isocyanate compound is added to an ink base material; (III) a resin composition layer containing (A) a polyolefin having a melt flow rate of 0.1 to 100 g / 10 min, and (B) two or more epoxy groups in the molecule. And an epoxy compound having a molecular weight of 3000 or less,
(A) a layer composed of a resin composition in which 0.01 to 5 parts by weight of an epoxy compound (B) is added to 100 parts by weight of a polyolefin; Since it is in contact with the layer, an extremely strong effect of improving the adhesiveness between the (II) printing layer and the (III) resin composition layer can be brought about. In addition, since the printing ink containing the (b) isocyanate compound is used, the adhesion between the (I) base layer and the (II) printing layer is also excellent.

The resin composition further comprises (C) an olefin resin having a functional group capable of reacting with an epoxy group, and (A) a polyolefin and (C) a functional group capable of reacting with an epoxy group. The ratio of the olefin resin having a functional group capable of reacting with the epoxy group to the resin component composed of the olefin resin is less than 30% by weight, and the epoxy compound (B) to 100 parts by weight of the resin component. Is added in an amount of 0.01 to 5 parts by weight, the adhesion between the (II) printing layer and the (III) resin composition layer can be further improved.

The method for producing a laminate of the present invention
(I) At least one surface of the base material layer has (a) a molecular weight of 50
(II) a printing layer is formed by printing using a printing ink to which an ink modifier containing a saturated copolymerized polyester having a melting point of 200 to 50,000 and a melting point of 200 ° C. or less and (b) an isocyanate compound is added; On this (II) printing layer, the melt flow rate (A) is 0.1 to 100 g /
(A) polyolefin 1 having a polyolefin of 10 minutes and (B) an epoxy compound containing two or more epoxy groups in the molecule and having a molecular weight of 3000 or less.
(B) 0.01 to 100 parts by weight of the epoxy compound
Since the production method is characterized by laminating the resin composition layer (III) composed of the resin composition to which 5 parts by weight are added by an extrusion lamination method without using an anchor coat agent, the (II) printing layer and the (II) A laminate having excellent adhesiveness between the III) resin composition layer and between the (I) base material layer and the (II) printing layer can be obtained.

Continued on the front page F-term (reference) 4F100 AH02C AH03B AJ02C AK01C AK03C AK04J AK06 AK24J AK25J AK41A AK41B AK41J AK42 AK62C AK66C AK70C AK71C AK80C AL01B AL05C AL07C BA00 EBAB BAH YY00C 4J039 AB02 AB08 AD01 AD05 AD08 AD14 AE04 AE06 AF01 AF02 BA04 BA13 BA35 BC32 BC39 BE01 BE02 BE09

Claims (7)

[Claims] (I) a base layer, (II) a printing layer, and (II)
(I) a laminate having (a) a molecular weight of 5,000 to 5,000.
0, a saturated copolymerized polyester having a melting point of 200 ° C. or less,
(B) a layer formed on at least one side of the base material layer by printing using a printing ink in which a printing ink modifier containing an isocyanate compound is added to an ink base material; The composition layer comprises: (A) a polyolefin having a melt flow rate of 0.1 to 100 g / 10 minutes;
(B) an epoxy compound having two or more epoxy groups in the molecule and having a molecular weight of 3000 or less;
(B) a layer of a resin composition in which 0.01 to 5 parts by weight of an epoxy compound is added to 100 parts by weight of a polyolefin; A laminate characterized by being in contact with. 2. The method according to claim 1, wherein (I) a base material layer, (II) a printing layer, and (II)
(I) a laminate having (a) a molecular weight of 5,000 to 5,000.
0, a saturated copolymerized polyester having a melting point of 200 ° C. or less,
(B) a layer formed on at least one side of the base material layer by printing using a printing ink in which a printing ink modifier containing an isocyanate compound is added to an ink base material; The composition layer comprises: (A) a polyolefin having a melt flow rate of 0.1 to 100 g / 10 minutes;
(B) an epoxy compound containing two or more epoxy groups in the molecule and having a molecular weight of 3000 or less, and (C) an olefin resin having a functional group capable of reacting with the epoxy group, and (A) a polyolefin And (C) a ratio of the olefin resin having a functional group capable of reacting with the epoxy group to the resin component composed of the olefin resin having a functional group capable of reacting with the epoxy group is less than 30% by weight,
And (B) a resin composition in which 0.01 to 5 parts by weight of an epoxy compound is added to 100 parts by weight of the resin component. A laminate characterized by being in contact with a material layer. 3. The laminate according to claim 1, wherein the epoxy compound (B) is an epoxidized vegetable oil. 4. The (C) olefin resin having a functional group capable of reacting with an epoxy group has at least one group selected from the group consisting of an acid anhydride group, a carboxyl group and a metal salt of a carboxylic acid. 3. The laminate according to claim 2, wherein the laminate is an olefin-based copolymer or a modified olefin resin. 5. The (C) olefin resin having a functional group capable of reacting with an epoxy group is an ethylene-maleic anhydride copolymer or an ethylene-maleic anhydride- (meth) acrylate copolymer. 3. The laminate according to claim 2, wherein: 6. The laminate according to claim 1, wherein (I) the base layer is made of polyester. (A) a molecular weight of 5,000 to 50,000,
A saturated copolymerized polyester having a melting point of 200 ° C. or lower,
(I) a printing layer is formed on at least one surface of the base layer by printing using a printing ink in which a printing ink modifier containing an (b) isocyanate compound is added to an ink base material; (II) On the printing layer, (A) a polyolefin having a melt flow rate of 0.1 to 100 g / 10 min, and (B) an epoxy containing two or more epoxy groups in a molecule and having a molecular weight of 3000 or less. A resin composition layer comprising a compound (A) and (B) 0.01 to 5 parts by weight of an epoxy compound with respect to 100 parts by weight of a polyolefin; A method for producing a laminate, comprising laminating by an extrusion lamination method without using an agent.