JPH0269587A - Water-base adhesive for polyolefin - Google Patents

Abstract

PURPOSE:To provide the subject adhesive capable of bonding polyolefins at room temperature and composed of an emulsion of vinyl acetate/ethylene copolymer, etc., and a neutralized product of a compound having acrylic copolymer as the main chain and polyalkylene imine structure on the side chain. CONSTITUTION:The objective adhesive contains (A) a PVA-containing emulsion of vinyl acetate/ethylene copolymer or vinyl acetate/ethylene/acrylic acid ester, (B) a neutralized product of a compound having acrylic copolymer as a main chain and alkylene imine structure on the side chain and produced by reacting an alkylene imine to a carboxyl group of a carboxyl-containing acrylic copolymer and preferably further (C) an epoxy resin. The adhesive quickly develops initial adhesive force and has excellent water-resistance and heat-resistance.

Description

[Detailed description of the invention] Industrial applications The present invention relates to aqueous adhesives for polyolefins.

More specifically, the present invention relates to an aqueous emulsion type adhesive that can bond polyolefins at room temperature, develops initial adhesive strength quickly, and has excellent water resistance and heat resistance.

BACKGROUND ART Conventionally, adhesives for plastics containing polyolefins include vinyl acetate-ethylene copolymer emulsions, polyalkylene polyamines, and vinyl acetate-ethylene copolymer emulsions described in, for example, Japanese Patent Publication No. 59-2474 or Japanese Patent Application Laid-open No. 58-213071. Products containing polyethyleneimine or polyamine polyamide are known.

Problems to be Solved by the Invention However, the above-mentioned conventional adhesives have the following drawbacks (a) to (c).

(a) The adhesion range of polyolefins is specified by Japanese Industrial Standards [
Wetting test method for polyethylene and polypropylene (J
Measurement of the wettability index is used as an indicator according to IS K6768)J, but with conventional adhesives, the wettability index is 33 to 40 dy.
Polyolefins in the n/cm range cannot be practically bonded, and only polyolefins above 41 dyn/cm can be practically bonded, thus limiting the polyolefin materials that can be bonded.

(b) Even with polyolefin materials that can be bonded, conventional adhesives have a slow initial bonding speed and poor workability, and can only provide adhesive products with poor water resistance, heat resistance, cold resistance, etc. do not have.

(c) The adhesive product becomes discolored or colored, impairing its quality value.

Means for Solving the Problems The present inventors have conducted extensive research in order to eliminate all the drawbacks of conventional adhesives. As a result, the following (A) component (B
It has been found that a desired adhesive in which all of the drawbacks (a) to (c) above are eliminated can be obtained only when component (a) is blended. The present invention was completed based on this knowledge.

That is, the present invention provides (A) a vinyl acetate-ethylene copolymer emulsion or a vinyl acetate-ethylene-acrylic acid ester copolymer emulsion containing polyvinyl alcohol, and (B) a carboxyl group of an acrylic copolymer having a carboxyl group. A neutralized product of a compound having an acrylic copolymer in the main chain and a polyalkylene imine structure in the side chain, obtained by reacting alkylene imine (
(hereinafter referred to as "acrylic amine polymer neutralized product")).

In the present invention, the vinyl acetate-ethylene copolymer emulsion or the vinyl acetate-ethylene-acrylic acid ester copolymer emulsion used as component (A) contains polyvinyl alcohol. The polyvinyl alcohol contained has an average saponification degree of 60 to 10.
0 mol% and an average degree of polymerization of 300 to 3000 are suitable, and the content is 1 to 10% by weight based on the resin solid content.
Preferably it is 2 to 8% by weight. Furthermore, in the present invention, emulsifiers and dispersants other than polyvinyl alcohol may be used in combination as an auxiliary agent for controlling the particle system, increasing emulsifying power, etc.

The vinyl acetate-ethylene copolymer has a copolymerization ratio of 90 to 60 parts by weight of vinyl acetate and 10 to 40 parts by weight of ethylene.
Parts by weight are preferred. If the ethylene content is less than 10 parts by weight, the water resistance and cold resistance of adhesive products made with adhesives containing such copolymers tend to decrease, and if the ethylene content exceeds 40 parts by weight, agglomeration may occur. Both are unfavorable because they tend to reduce the strength and the adhesive strength and heat resistance of the resulting adhesive.

The vinyl acetate-ethylene-acrylic ester copolymer preferably has a copolymerization ratio of 90 to 40 parts by weight of vinyl acetate, 5 to 30 parts by weight of ethylene, and 5 to 30 parts by weight of acrylic ester. Here, the acrylic ester is one in which the number of carbon atoms in the alkyl group of the acrylic ester moiety is in the range of 1 to 10, and specifically, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, etc. Examples include acrylate, octyl acrylate, and 2-ethylhexyl acrylate. These can be used alone or in combination of two or more. When the total amount of ethylene and acrylic acid ester is less than 10% by weight, the water resistance and cold resistance of adhesive products made with adhesives containing such copolymers tend to decrease. If the total amount of the acid ester exceeds 60 parts by weight, it is not preferable because there is a risk that the adhesive strength will tend to decrease due to a decrease in cohesive force and the heat resistance of the adhesive product will decrease.

The neutralized acrylic amine polymer used as component (B) in the present invention has a structure in which the main chain is an acrylic polymer and the side chain is represented by the following formula.

In the above formula, R1 and R2 are hydrogen atoms or have 1 carbon number
-3 alkyl group, and n is usually in the range of 1-3. Further, HX represents an acid and indicates an R,R2 state.

In the above, when n=1, the side chain is only an amino group, but when n=2 or more, the terminal becomes an amino group, and the middle becomes an imino group. The amounts of these amino groups, amino groups, and imino groups can be expressed as amine hydrogen equivalents. This amine hydrogen equivalent is calculated by the following formula.

Amine hydrogen equivalent type i (g-solid/eQ) = s
, XNX52 Titration amount of the liquid (sample) W: Total polymerization (g) of the diluted sample liquid. The PVSK liquid is a polyvinyl calcium sulfate solution (
For colloid titration, commercially available product).

A compound having an acrylic copolymer in the main chain and a polyalkyleneimine structure in the side chain (acrylic amine polymer) contains 1 to 20 carboxyl group-containing unsaturated monomers.
% by weight and 99 to 80% by weight of an unsaturated monomer mainly composed of acrylic esters in a suitable organic solvent. It is produced by reacting an alkylene imine having an alkyl group having 1 to 3 carbon atoms, such as imine and propylene imine.

Examples of the carboxyl group-containing unsaturated monomer include acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and acid anhydrides thereof. Among these, acrylic acid and methacrylic acid are preferred.

The unsaturated monomer containing acrylic ester as a main component must contain at least 50% by weight of acrylic ester, and if such an unsaturated monomer is not used, the polyolefin material Good adhesion becomes difficult to develop. As the acrylic ester, those having an alkyl substituent having a carbon number of 1 to 8 can be widely used, and specific examples include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, and t-butyl acrylate. , hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, and the like. These may be used alone or in combination of two or more. Unsaturated monomers other than acrylic esters are used for the purpose of improving the cohesive force of the acrylic amine polymer and improving its heat resistance, or for the purpose of imparting hydrophilicity and promoting water solubility. Examples of monomers intended to improve cohesive force include styrene, methyl methacrylate, ethyl methacrylate, vinyl acetate, etc. whose single polymer has a glass transition temperature of room temperature or higher; As a quantity,
Acrylamide, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate,
Examples include hydroxyethyl methacrylate. As an acrylate monomer that provides good adhesion,
Preferred examples include ethyl acrylate, butyl acrylate and 2-ethylhexyl acrylate. Styrene and methyl methacrylate are preferably mentioned as monomers that improve cohesive force. Preferable monomers that can promote hydrophilicity include dimethylaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate.

Examples of organic solvents used include lower alcohols such as methyl alcohol, ethyl alcohol, n- or isopropyl alcohol, n-, iso- or t-butyl alcohol, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, and propylene glycol. Examples include alkylene glycols such as monomethyl ether, ketones such as acetone and methyl ethyl ketone, toluene, xylene, ethyl acetate, and butyl acetate.

Solution polymerization of the carboxyl group-containing unsaturated monomer and the unsaturated monomer mainly composed of acrylic acid ester is carried out in the presence of an initiator such as azobisisobutyronitrile or benzoyl peroxide. ℃ degree, 4-24
After waiting for about an hour, the carboxyl group-containing acrylic polymer is polymerized.

In order to produce an acrylamine polymer by reacting the carboxyl group of the carboxyl group-containing acrylic polymer thus obtained with an alkylene imine, the reaction conditions described in, for example, US Pat. No. 3,634,372 may be followed.

What is important for the present invention is to bring the acrylamine polymer obtained above into a neutralized state. By bringing it into this neutralized state, it is possible to obtain good miscibility with component (A), and it is possible to provide an excellent adhesive effect to polyolefins.

Examples of the acid used for this neutralization include mineral acids such as hydrochloric acid, hydrobromic acid, nitric acid, and sulfuric acid, carboxylic acids such as acetic acid and propionic acid, and oxycarboxylic acids such as lactic acid and tartaric acid. In this neutralization step, it is preferable that the acid used be an aqueous solution, so the selection of a diluting solvent for the acrylic amine polymer is necessary to maintain solubility of the acrylic amine polymer before and after neutralization, and to create a homogeneous dissolution system even in a water-containing state. It is desirable that the solvent be hydrophilic in order to maintain the When neutralizing the synthesized acrylic amine polymer, if the organic solvent used in solution polymerization is a hydrophilic solvent such as lower alcohols, alkylene glycols, or ketones, the neutralization step may be started immediately; If a solvent other than the above is used, the polymer may be taken out once and diluted again with a predetermined solvent.In short, it is sufficient that the polymer solution after neutralization remains a homogeneous solution even if it is in a water-containing state. The amount of acid for neutralization is not particularly limited, and the pH
is adjusted to a range of 2 to 7. If it is not in a water-containing state, a small amount of water may be added to maintain the above pH range.

The acrylic amine polymer used in the present invention has an amine hydrogen equivalent (g-sol i
d/eq) in the range of 200 to 700 is suitable.

Particularly preferably 300 to 600. When the amine hydrogen equivalent is more than 700, the adhesion to polyolefins tends to be poor; on the other hand, when the amine hydrogen equivalent is more than 20
When it is less than 0, the water resistance of the adhesive product tends to decrease, which is not preferable.

Further, the molecular weight of the acrylamine polymer used in the present invention is suitably in the range of 20,000 to 400,000, particularly 50,000 to 400,000.
The range of ooo to 300,000 is preferable. If 2000
When it is less than 0, the initial adhesion speed tends to decrease and the water resistance of the adhesive product tends to decrease, and when it exceeds 400,000, the miscibility tends to decrease.

When blending the components (A) and (B) of the present invention, the emulsion (A) is usually adjusted to a pH range of 3 to 7, and the hydrophilic organic solvent of the neutralized acrylic amine polymer (B) is used. It is preferable to adopt a method of blending a solution dissolved in . In this case, the concentration of the acrylic amine polymer neutralized solution is preferably 20 to 70%. If it is less than 20% by weight, the amount of solvent contained in the adhesive will increase and the viscosity may become too low, and if it is more than 70% by weight, miscibility will deteriorate.

As for the blending ratio of component (A) and component (B), the resin content of (B) is suitably 1 to 20 parts by weight, particularly preferably 1.5 to 10 parts by weight, per 100 parts by weight of resin content of (A). Parts by weight. If the resin content (B) is less than 1 part by weight, adhesion to polyolefins and heat resistance tend to be poor, while if it exceeds 20 parts by weight, it becomes difficult to obtain good miscibility with component (A), so it is preferable. do not have.

In the present invention, when an epoxy resin is blended, higher heat resistance, water resistance, boiling resistance, and boiling repeatability can be imparted to the resulting composition. As the epoxy resin, compounds having two or more epoxy groups in the molecule can be widely used, such as bisphenol A-diglycidyl ether, bisphenol F-diglycidyl ether, bisphenol S-diglycidyl ether, resorcinol diglycidyl ether, Hydrobisphenol A-diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, phthalate diglycidyl ester,
Examples include bifunctional epoxy resins such as dimer acid diglycidyl ester, and polyfunctional epoxy resins such as triglycidyl isocyanurate, tetraglycidyl diaminodiphenylmethane, tetraglycidyl metaxylene diamine, and cresol novolak polyglycidyl ether. Among these epoxy resins, lipophilic types are preferred in order to maintain the adhesion effect of hydrophilic acrylic amine polymer neutralized products to polyolefins.

Among these, particularly preferred are bisphenol A-diglycidyl ether and bisphenol F-diglycidyl ether. The amount of these epoxy resins added is generally 1 to 40 parts by weight, preferably 2 to 30 parts by weight, per 100 parts by weight of the resin component (A). If the amount of epoxy resin added is extremely large, adhesion to polyolefin tends to become poor, which is not preferable. The method of adding epoxy resin to the emulsion (A) is as follows:
In the case of a liquid resin, the method of directly adding it and forcibly emulsifying it by high-speed stirring is the method, or if the solid epoxy resin or liquid resin is viscous, 1/4 to 1/4 of the added epoxy resin can be used.
A common method is to dissolve the compound in an approximately equal amount of a soluble organic solvent, add the compound, and emulsify it by stirring, but the method is not limited to these methods.

The adhesive of the present invention can be appropriately added with a third component that is included in ordinary emulsion type adhesives. For example, small amounts of toluene for thickening purposes, organic solvents such as xylene, butyl acetate, and cyclohexanone, water-soluble polymers such as hydroxyethyl cellulose and methyl cellulose, fillers such as calcium carbonate, clay talc, wheat flour, and cellulose powder, and water-resistant A small amount of phenol resin, urea resin, melamine resin, etc. can be appropriately blended to improve properties and heat resistance.

Using the adhesive of the present invention, wet lamination can be performed with room temperature bonding. With conventional adhesives, if the wetting index decreases, practical adhesion can only be achieved by heating to increase the surface activation state, which requires a large investment in equipment such as drying equipment. The wettability index for adhesives is 33~
Even polyolefins of 40 dyn/cm can be bonded at room temperature without heating.

Furthermore, safe and stable bonding can be achieved even in the range of 5°C, which is assumed to be the temperature of an indoor workplace during the extremely cold season. Of course, when using the adhesive of the present invention, in order to further shorten the bonding time, it is also possible to apply semi-dry lamination in which the adhesive is heated or heated to slightly evaporate water after application. .

Effect of the invention The adhesive of the present invention has the following advantages.

(1) If the adhesive of the present invention is used, practical adhesion is possible even with polyolefins with a wettability index of 33 to 40 dyn/cm according to JIS K6768 in wet lamination at room temperature, and the adhesion to polyolefins is stabilized. and materials can be freely selected.

(2) By using the adhesive of the present invention, excellent heat resistance, water resistance, cold resistance, etc. can be imparted to the resulting adhesive product, and the quality of the adhesive product can be improved.

(3) Because the initial adhesion development speed is fast, the pressing time is short.
It can contribute to improving productivity.

(4) The adhesive product will not be discolored or colored and its quality value will not be impaired.

Example Examples are given below to further clarify the present invention.

Hereinafter, "parts" simply means "parts by weight" and "%" means "% by weight."

Example 1 Vinyl acetate containing 6% by weight of polyvinyl alcohol with a degree of saponification of 88 mol% and an average degree of polymerization of 1700 based on the resin content
Ethylene copolymer emulsion (vinyl acetate: ethylene =
82:18 (weight ratio), viscosity 2000 cps/30°C,
(pH 3.8, solid content 55.3%) is designated as EVA emulsion A.

A neutralized acrylic amine polymer to be added to this was obtained by the following method. That is, 50 parts of isopropyl alcohol was charged into a four-bottle flask equipped with a stirrer, a thermometer, a condenser, a dropping funnel, and a nitrogen gas introduction tube, and the temperature was adjusted to 80°C, and 30 parts of butyl acrylate, 1 part of dimethylaminoethyl acrylate, A monomer mixture consisting of 10 parts of methyl methacrylate, 5 parts of styrene, and 4 parts of methacrylic acid to which 0.5 part of azobisisobutyronitrile was added as an initiator was added dropwise while blowing nitrogen gas, and then aged at 80°C for 24 hours. After a period of time, a carboxyl group-containing acrylic polymer solution was obtained. This polymer solution was cooled to 20°C, 4 parts of ethyleneimine was added dropwise over 20 minutes, the temperature was gradually raised to 75°C, and after being left at the same temperature for 5 hours, a distillation apparatus was set in a four-row flask. , While reducing the pressure and heating, add ethylene glycol monoethyl ether in the same amount as the effluent, remove unreacted ethyleneimine together with isopropyl alcohol, replace the solvent with ethylene glycol monoethyl ether, and reduce the solid content to 49 to It was adjusted to 50%.

When a portion of this acrylic amine polymer solution was taken and mixed with water, it became gel-like.

Next, 35% hydrochloric acid was added little by little to the above acrylamine polymer solution to adjust the pH to 5.0 to obtain a solution of a neutralized acrylamine polymer. When this solution was mixed with water, it was completely dissolved. When this was taken out from the flask and its properties were measured, the amine hydrogen equivalent was 432, the average molecular weight was about 160,000, and the solid content was 50.2%. This polymer solution will be referred to as acrylic amine polymer neutralized solution B.

For comparison, a 50% aqueous solution of triethylenetetramine (this is referred to as polyalkylenepolyamine C) and a 30% aqueous solution of polyethyleneimine were used as polyalkylene polyamines.
An aqueous solution (product name P-1000゜manufactured by Nippon Shokubai Chemical Industry ■, referred to as polyethyleneimine D) and a polyamine polyamide as product name Tomide 255 (solid content 100
A 50% aqueous dispersion (this will be referred to as polyamine polyamide E) of % Fuji Chemical Industry Co., Ltd.) is used.

B-E was blended into EVA emulsion A as shown in Table 1 below.

Wet lamination bonding was performed at room temperature (25° C.) under the conditions shown below using these adhesives (Product 1 of the present invention and Comparative Examples 1 to 3).

(a) Films shown in Table 2 below were used as test materials polyolefins.

Table 2 (b) Adhesive conditions Adhesive method: Wet lamination at room temperature (25°C) Adhesive work: After coating the polyolefin film surface with a bar coater, cover the plywood with the film, depressurize it with a rubber roll, and leave it as it is until the next day. do.

Coating amount: 60g/m2 The physical properties of the adhesive product obtained above were measured as follows.

■Normal adhesion test Cut the adhesive into 25mm x 100mm and heat at 20°C1.
A 180 degree peel test is performed in a constant temperature room at 65% RH.

Tensile speed: 200 mm/min, strength: median value, number of specimens: 5.

■ Water resistant adhesion test A specimen of the same shape as ■ was immersed in water at 20°C for 24 hours.
Perform the 180 degree peel test while wet as in (■).

■Heat-resistant adhesion test A sample having the same shape as in ■■ is left in an oven at 60°C for 1 hour, then taken out and immediately subjected to a 180 degree peel test in the same manner as in ■■ while still hot.

■ Cold resistant adhesion strength Peel off about half of a sample with the same shape as ■ in advance, and apply -5.
After leaving it in the refrigerator at ℃ for 24 hours, take it out and peel it off immediately.

O: Peeling accompanied by wood breakage ×: Interfacial peeling ■ JAS class 2 immersion peeling test According to the JAS method, a 75 mm square test piece was left in warm water at 70°C for 2 hours and then dried at 60°C for 3 hours. Compliance standards are based on JAS compliance standards.

Table 1 Adhesive Crab kg/25mm The results of this test showed that OPP film with wetting index of 366 yn/am, CPP film with wetting index of 38 dyn/am and 40
In all PE films of dyn/cm, the product 1 of the present invention exhibited a strength of 4 kg/25 mm or more, and the peeling state was 100% that of plywood breaking. Furthermore, it has excellent water resistance, heat resistance, and cold resistance, and also passed the JAS type 2 immersion peel test.

On the other hand, in Comparative Examples 1 to 3, the strength value was less than 1 kg/25 mm, and the peeling state was also interfacial peeling, and it could not be said that it was bonded.

Example 2 Vinyl acetate-ethylene copolymer emulsion containing 8% by weight of polyvinyl alcohol with a degree of saponification of 95 mol% and an average degree of polymerization of 1700 per resin (vinyl acetate: ethylene = 8
0:20 (weight ratio), viscosity 6000cps/30℃, p
H4.3, solids content 53.2%) into EVA emulsion F
shall be.

As a neutralized product of the acrylic amine polymer, 50 parts of isopropyl alcohol was charged in the same manner as in Example 1, butyl acrylate 20 parts ethyl acrylate 10 parts methyl methacrylate 15 parts dimethylaminoethyl acrylate 0.5 part acrylic acid
1 part methacrylic acid
After solution polymerizing 3.5 parts, 4.5 parts of ethyleneimine was reacted. Next, using propylene glycol monomethyl ether in place of ethylene glycol monoethyl ether in Example 1, isopropyl alcohol and unreacted ethyleneimine were removed in the same manner as in Example 1 to obtain a solution of an acrylic amine polymer. To make this water solubilized,
The mixture was neutralized with hydrochloric acid in the same manner as in Example 1 to a pH of 5.0. When the properties of this product were investigated, it was found that the amine hydrogen equivalent was 415, the average molecular weight was 120,000, and the solid content was 51.5%.

This polymer solution is referred to as acrylic amine polymer neutralized solution H.

For this EVA emulsion F, using an acrylic amine polymer neutralized solution H, a polyalkylene polyamine C, a polyethylene imine D, and a polyamine polyamide E,
Various adhesives were prepared in the proportions shown in Table 4 below.

These adhesives were used for 2 hours at room temperature (25℃) under the following conditions.
Wet lamination was performed using an axially stretched polypropylene film (OPP film) and high-quality paper. This OP
P film has adhesive strength of 47 dyn/cm (thickness 2
5μ, transparent) was selected.

For wet lamination, 20 g/m2 of each adhesive was applied to the surface of the OPP film using a bar coater, and high-quality paper was immediately bonded to the film, followed by testing on the next day. In addition, gluing work and curing are 25
It was ℃.

(Test Items) ■ Initial Adhesive Strength Test After pasting together using the method described above, the sheets were peeled off by hand after each period of time, and the initial adhesive strength was examined by breaking the high-quality paper.

(2) Adhesiveness Test The adhesive was peeled off by hand at 25°C the day after adhesion, and those that broke the high-quality paper were rated 0, and those that peeled at the interface were rated x.

■ Heat-resistant creep test Fix the upper part of the 25IIlffI width test piece, and
A weight of 0 g is suspended, the temperature is raised in an oven at a rate of 3 to b/min, and the temperature at which the adhesive surface (length 25 mm) peels off at the interface and the weight falls is measured.

■ Cold resistance adhesion test After leaving in a refrigerator at -5°C for 24 hours, take it out and peel it off immediately.

O: Peeling accompanied by paper tear (break) ×: Interfacial peeling■ Water resistant adhesion test After immersing in water at 25° C. for 24 hours, the adhesive was forcibly peeled off to check the adhesion state.

O: Peeling accompanied by paper tear (breakdown) ×: Interfacial peeling ■ Yellowing resistance test The yellowing was examined by irradiating with a fade meter for 10 days. Fade meter: 4 National Germicidal Lights, 250-3
00 μm Regarding the initial adhesive strength in Table 1, Invention Product 2 caused paper tearing in 10 minutes, but Comparative Examples 4 to 6 required 30 to 60 minutes to exhibit paper tearing.

Regarding the adhesion test, the OPP film was 47 dyn/
cm and a high wettability index, and adhesion was possible in Comparative Examples 4 to 6, but in the adhesive property test, Invention Product 2 was significantly superior to Comparative Examples 4 to 6.

Example 3 Wet lamination bonding was carried out in the same manner as in Example 2 at 25° C. using the adhesive of Example 2 and an oPP film with a wetting index of 40 dyn/cm. As a result, the present invention product 3
Although paper tearing occurred in 10 minutes, adhesives other than those of the present invention easily peeled off at the interface the next day without causing paper tearing.

Example 4 Vinyl acetate-ethylene-2-ethylhexyl acrylate emulsion copolymerized using a nonionic-anionic surfactant (copolymerization ratio 65:20:15, viscosity 300
cps (30℃), pH 4.8, solid content 55.2%)
is referred to as EvA-acrylic emulsion G.

For this EVA acrylic emulsion G, polyvinyl alcohol (saponification degree 88 mol%, average polymerization degree 2400
) and the acrylic amine polymer neutralized solution B used in Example 1 were used to make the following formulation.

Using these adhesives, the wettability index was 36 at 15°C.
Wet lamination was performed in the same manner as in Example 1 using a transparent CPP film of dyn/cm and a thickness of 25 μm and plywood, and an adhesive property test was conducted. The results were as follows.

Table 7 The following is clear from Table 7 above. That is, if it does not contain an acrylamine polymer, interfacial peeling will occur,
All strengths, including normal strength, were weak. Furthermore, when polyvinyl alcohol was not contained and only the neutralized acrylic amine polymer was contained, the strength was less than half that of the case where both were contained, and the peeling state was cohesive failure.

Example 5 For Invention Product 1 of Example 1 and Comparative Examples 1 to 3, 5 parts of Epicor) 828 (manufactured by Yuka Shell Epoxy ■), which is bisphenol A diglycidyl ether, was dissolved in 2 parts of toluene. An epoxy resin solution was blended. The formulation is shown in Table 8.

Using these adhesives (inventive product 5 and comparative examples 10 to 12) and the same test materials as in Example 1 (CPP film, CPP film, PE film), under the same bonding conditions as in Example 1, room temperature (25 Wet lamination bonding was carried out at a temperature of

In addition to the test method of Example 1, the following method was added to measure the physical properties of the adhesive product obtained above.

■ Measurement of the physical properties of the adhesive product in Hot water adhesion test Example 1 A test piece (25 mm x 100 mm) with the same shape as in ■ was immersed in warm water at 60°C for 3 hours, then soaked back in room temperature water for 30 minutes, and then wet. Mama180
Perform a peel test.

Tensile speed: 200 mm/min, strength: median value, number of specimens: 5.

■ Measurement of the physical properties of the adhesive product in Example 1 of boiling-resistant adhesive strength test After immersing a test piece (25 mm x 100 mm) in the same shape as in ■ in boiling water for 4 hours,
Soak back in room temperature water for 30 minutes and perform a 180 degree peel test while still wet.

Tensile speed: 200 mm/min, strength: median value, number of specimens: 5.

JASI Immersion Peeling Test According to JAS method, a 75a+m square test piece is immersed in boiling water for 4 hours and then dried at 60°C for 20 hours.

After immersing it in boiling water again for 4 hours, it was dried at 60°C for 3 hours. Compliance standards are based on JAS compliance standards.

Repeated boiling test A 75m+n square test piece was immersed in boiling water for 4 hours, then heated to 60°C.
This step is performed 10 times, with the step of drying for 20 hours in a vacuum cleaner as one step.

Compliance standards are based on JAS compliance standards.

Table Adhesive Crab kg/25mm Adhesive Crab kg/25mm Adhesive Crab kg/25u As a result of this test, CPP with a wettability index of 36 dyn/cm
film, 38 dyn/cm CPP film and 40
Inventive product 5 in all PE films of dyn/cm
showed a strength of 4 kg/25 [11111 or higher, and the peeling state was 100% that of plywood breaking.

Furthermore, the present invention product 5 had generally better normal adhesive strength, water-resistant adhesive strength, and heat-resistant adhesive strength than the present invention product 1 of Example 1, which did not contain an epoxy resin.

Inventive product 5 also showed good results in hot water resistant adhesive strength and boiling resistant adhesive strength, and passed the JASI immersion peel test and boiling cyclic test.

On the other hand, in Comparative Examples 10 to 12, although the adhesive properties were slightly improved compared to Comparative Examples 1 to 3, the adhesive strength was low overall, and the peeling state was interfacial peeling, and compared to the products of the present invention, they were much better. Adhesive strength was insufficient.

Example 6 EVA emulsion F1 of Example 2 Acrylic amine polymer neutralized solution H and Epicote 8 as epoxy resin
The following formulation was carried out using No. 28 (manufactured by Yuka Shell Epoxy ■).

The values in Table 12 are parts by weight. The solid content is shown in parentheses, and the toluene in Inventive Product 6 was added for thickening, and the toluene in Inventive Product 7 was used as a solubilizer for Epicote 828 and as a thickener after addition.

Using this adhesive, the CPP film of Example 1 (38d
yn/am) and plywood were wet laminated at room temperature under the same conditions as in Example 1.

The physical properties of the adhesive products obtained above were measured according to the test methods of Examples 1 and 5.

Table 1 Adhesive Crab kg/25mm Inventive product 6 and inventive product 7 (epoxy resin formulation) both exhibited excellent adhesive properties. Among products 6 and 7 of the present invention, product 7 of the present invention was generally better.

(that's all)

Claims (1)

[Scope of Claims] [1] (A) Vinyl acetate containing polyvinyl alcohol
Ethylene copolymer emulsion or vinyl acetate-ethylene-acrylic acid ester copolymer emulsion, and (B) an acrylic copolymer in the main chain obtained by reacting an alkylene imine with the carboxyl group of an acrylic copolymer having a carboxyl group. A water-based adhesive for polyolefin containing a neutralized product of a compound having a polymer and having a polyalkyleneimine structure in its side chain. [2] (A) Vinyl acetate containing polyvinyl alcohol
Ethylene copolymer emulsion or vinyl acetate-ethylene-acrylic acid ester copolymer emulsion, (B) an acrylic copolymer in the main chain obtained by reacting an alkylene imine with the carboxyl group of an acrylic copolymer having a carboxyl group A neutralized product of a compound having a polyalkyleneimine structure in its side chain,
and (C) a water-based adhesive for polyolefin containing an epoxy resin.