JP3041079B2 - Solution adhesives and print lamination adhesives - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solution adhesive exhibiting good adhesiveness to various substrates, and in particular, has excellent adhesiveness to vinyl chloride resin and is also effective as an adhesive for print lamination. To a solution adhesive that can be used for

[0002]

TECHNICAL BACKGROUND OF THE INVENTION Soft vinyl chloride resin has flexibility,
It has many excellent properties such as transparency and toughness, and has the advantage that properties such as flexibility can be freely adjusted by the amount of plasticizer added. Used for a wide range of applications. However, since bonding of a soft vinyl chloride resin is not always easy, many studies have been made on an adhesive for a soft vinyl chloride resin, but no satisfactory product has yet been found.

[0003] For example, as an adhesive for a soft vinyl chloride resin, a solution type adhesive such as chloroprene rubber, nitrile rubber, and polyester has been widely used. Due to the bleed phenomenon in which the plasticizer diffuses into the adhesive layer, there has been a problem that the adhesive force of the adhesive layer decreases with time. In addition, these adhesives have a high viscosity, and when an adhesive layer is formed on an adherend, the time required for the adhesive layer to harden or gelate and to maintain a sufficient adhesive force is lost. In other words, since there is a problem such as a short pot life (usable time), an adhesive is applied to at least one of a printed material (printing plate) and a resin film, and then the two are laminated and adhered to each other. Was inferior in workability and could not be used.

[0004] On the other hand, various solution-type adhesives are known as adhesives for print lamination, but each have some disadvantages, and they have not always been satisfactory. For example, an ethylene-vinyl acetate copolymer adhesive has a long pot life and good adhesiveness to an oriented polypropylene (OPP) film, and thus is often used for bonding an OPP film to printing paper. When it is used for laminating a printing paper with a film of polyester or polyester resin, there is a problem that the adhesive strength is insufficient. Further, urethane resin-based and acrylic resin-based adhesives exhibit good adhesive strength to films such as vinyl chloride resin and polyester, but also have a problem that the pot life is short.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to solve the problems associated with the prior art as described above. It is an object of the present invention to provide a solution adhesive that can impart viscosity and has a long pot life, and also exhibits excellent performance as an adhesive for print lamination.

[0006]

SUMMARY OF THE INVENTION The solution adhesive according to the present invention is obtained by copolymerizing [I] ethylene, a (meth) acrylic acid ester and carbon monoxide, wherein the component unit derived from ethylene is 40 to 92% by weight, Ethylene / (meth) acrylate / carbon monoxide containing 5 to 50% by weight of component units derived from (meth) acrylate and 3 to 20% by weight of component units derived from carbon monoxide A copolymer and a [II] soluble solvent, wherein the content of the ethylene / (meth) acrylate / carbon monoxide copolymer [I] is 1 to 50% by weight. I do.

The adhesive for print lamination according to the present invention comprises the above-mentioned solution adhesive, and is used for print lamination in which an adhesive is applied to at least one of a printed material and a resin film, and then the two are laminated and adhered. Features.

[0008]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the solution adhesive and the print lamination adhesive according to the present invention will be described in detail.

The solution adhesive according to the present invention contains an ethylene / (meth) acrylate / carbon monoxide copolymer [I] as a base polymer and a soluble solvent [II].

Such an ethylene / (meth) acrylate / carbon monoxide copolymer [I] comprises ethylene,
A (meth) acrylic acid ester and carbon monoxide are copolymerized, and a random copolymer is particularly preferably used. As the (meth) acrylate, the formula CH ₂ = C
An alkyl acrylate or an alkyl methacrylate represented by HCOOR or a formula CH ₂ ＲC (CH ₃ ) COOR wherein R is a linear or branched alkyl group having about 1 to 10 carbon atoms is preferable. Examples thereof include methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, and methyl methacrylate. Such (meth) acrylic acid esters may be used alone or in combination of two or more.

The ethylene / (meth) acrylate / carbon monoxide copolymer [I] used in the present invention contains 40 to 92% by weight of a component unit derived from ethylene.
Preferably 50 to 80% by weight, usually 5 to 50% by weight, preferably 10 to 40% by weight of component units derived from (meth) acrylic acid ester, and usually 3 to 4% by weight of component units derived from carbon monoxide. 20% by weight, preferably 5-1
Contains 5% by weight. Such a copolymer [I] can be produced by copolymerizing a monomer as a raw material in an amount corresponding to the content of the above component unit.

In such a terpolymer [I],
When the amount of the ethylene component unit exceeds the above range, the solubility of the copolymer [I] in the solvent is reduced, so that the obtained adhesive has a tendency to deteriorate in storage property, bonding workability and the like. When the amount of the ethylene component is less than the above range, the heat resistance and adhesive strength of the adhesive tend to decrease. When the amount of the (meth) acrylate component unit is less than the above range, the solubility of the copolymer [I] in the solvent is reduced, and the adhesiveness of the obtained adhesive, particularly the adhesive strength at a low temperature, is insufficient. Tend. When the amount of the carbon monoxide component unit is less than the above range, the adhesiveness of the obtained adhesive tends to be insufficient, and when the amount exceeds the above range, the weather resistance of the adhesive tends to decrease. is there.

The ethylene / (meth) acrylate / carbon monoxide copolymer [I] used in the present invention comprises 19
The melt flow rate measured at 0 ° C. and a load of 2160 g is 0.1 to 1000 g / 10 min, particularly 1 to 100 g / 10
Minutes.

In the solution adhesive according to the present invention, the copolymer [I] is contained in an amount of 1 to 50% by weight, preferably 5 to 30% by weight in the solution adhesive. In the solution adhesive according to the present invention, specific examples of the solubilizing solvent [II] used with the terpolymer [I] include aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; Cyclic ethers such as tetrahydrofuran and dioxane, ketones such as methyl ethyl ketone and methyl isobutyl ketone, halogenated hydrocarbons such as trichloroethylene and chlorobenzene, ethyl acetate, acetic acid
An acetate such as n-butyl can be exemplified. Among these, toluene, tetrahydrofuran, trichloroethylene and the like are particularly preferred. These soluble solvents [II] may be used alone or in combination of two or more.

Further, the solution adhesive according to the present invention comprises the terpolymer [I] and the soluble solvent [II] described above.
In addition to the above, other thermoplastic resins, rubbers, tackifier resins and various additives may be contained as necessary.

The solution adhesive according to the present invention comprises polyethylene, polypropylene, poly-1-butene, poly-4-methyl
-1- such as polyolefins such as pentene, ethylene / vinyl acetate copolymer, ethylene / (meth) acrylate copolymer, ethylene / vinyl alcohol copolymer, ethylene / (meth) acrylic acid copolymer Ethylene-polar monomer copolymer, polyester such as polyethylene terephthalate, polybutylene terephthalate, polyamide such as nylon 6, nylon 66, polycarbonate, polyvinyl chloride, polystyrene, AS
Resin, styrene resin such as ABS resin, metal, paper,
It can be applied to wood and the like. Such adherends may be of various shapes, such as films, sheets, hollow bodies, tubes, injection molded articles, woven fabrics, nonwoven fabrics,
It may be a foam or the like.

The solution adhesive according to the present invention can be used not only alone, but also as a primer for other adhesives, and can also be used as a mixture with other solution type adhesives. it can.

In order to perform adhesion using the solution adhesive according to the present invention, for example, an adhesive is applied to one of a pair of adherends, dried, and the other adherends are overlapped with each other to form an ethylene copolymer. A method in which the adhesive is applied under pressure at a temperature equal to or higher than the melting point of the adhesive, a method in which the adhesive is applied to both adherends, followed by drying, a method in which both adherends are overlapped, and a method in which the adhesive is applied under heat and pressure in the same manner as described above. A method can be adopted.

Since the solution adhesive according to the present invention has an appropriate viscosity and a long pot life, the adhesive is applied to at least one of a printed material (printing plate) and a resin film and then adhered to each other. It can be suitably used for print lamination. When the adhesive according to the present invention is used as an adhesive for print lamination, it is usually used in the form of a two-part adhesive in the same manner as a conventional ethylene / vinyl acetate copolymer adhesive. For example, the solution adhesive of the present invention prepares a solution containing the adhesive, a modified or unmodified rosin ester, and a chlorinated polyolefin such as chlorinated polypropylene, if necessary, and a curing agent at the time of use. By mixing an isocyanate-based compound, it can be suitably used as an adhesive for print lamination.

The modified or unmodified rosin ester has a residual carboxyl group and is usually 50 to 500 parts by weight, preferably about 60 to 300 parts by weight, per 100 parts by weight of the copolymer [II] in the solution adhesive. Used in the ratio of

The chlorinated polyolefin is used in an amount of about 0 to 300 parts by weight, preferably about 50 to 200 parts by weight, per 100 parts by weight of the ternary copolymer [II] in the solution adhesive.

The isocyanate compound is preferably a compound containing two or more isocyanate groups in the molecule. For example, low molecular weight diisocyanates such as hexamethylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and isophorone A reaction product of diisocyanate or the like with water or a polyhydric alcohol such as glycerin or trimethylolpropane, or a dimer or trimer of a low molecular weight diisocyanate can be used. It is preferable that such an isocyanate compound is previously dissolved in a solvent and mixed with the solution adhesive of the present invention. Examples of such a solvent include those exemplified above as the soluble solvent [II]. The isocyanate compound is a terpolymer [II] and a total amount of rosin ester of 10
It is preferably used in an amount of about 5 to 50 parts by weight with respect to 0 parts by weight.

[0023]

According to the solution adhesive of the present invention, the above-mentioned specific ethylene / (meth) acrylate / carbon monoxide copolymer [I] and the above-mentioned soluble solvent [II] are contained. Since the terpolymer (I) is contained in a specific amount, it provides a solution adhesive that exhibits good adhesiveness to not only a soft vinyl chloride resin but also many base materials and can impart appropriate viscosity. can do.

Further, since the adhesive for print lamination according to the present invention contains the above-mentioned solution adhesive, it exhibits good adhesiveness to many base materials and can impart appropriate viscosity, and has a long pot life. It is long and shows excellent performance as an adhesive for print lamination.

[0025]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0026]

Example 1 An ethylene copolymer (melt flow rate: 6 g / m) obtained by random copolymerization of 60% by weight of ethylene, 30% by weight of n-butyl acrylate, and 10% by weight of carbon monoxide.
10 minutes), the solvent solubility and adhesive strength were measured by the following methods.

The results are shown in Table 1. Take 10 to 30 g of the solvent-soluble resin in a 200 ml Erlenmeyer flask,
Various solvents are added so as to have a ratio of ３０30% by weight, sealed, and shaken in a constant temperature water bath at 30 ° C. for 24 hours. The dissolution state at this time is visually observed. Symbols 〇, △ and × in Table 1
Represents the following evaluation.

〇 --- Dissolves completely. Δ --- Partially dissolves. × --- Only swelling. -Dissolve the adhesive strength resin in toluene to prepare a 25% by weight solution. The obtained solution is uniformly applied to a 50 μ thick polyethylene terephthalate (PET) film or a 200 μ thick soft vinyl chloride (containing 60 parts by weight of dioctyl phthalate) film so as to have a thickness of 40 μ and air-dried.
Toluene is removed by further drying under reduced pressure for 3 hours to obtain a resin-coated PET film or a soft vinyl chloride film.

The above resin-coated PET film and
PET film or resin not coated with resin
Coated soft vinyl chloride film and resin coated
Not a soft PVC film and a heat sealer
At 120 ° C, 3Kg / cm ^TwoHeat bonding under 10 seconds
I do.

The obtained laminate is cut into strips having a width of 25 mm.
The peel strength is measured with a tensile tester at a tensile speed of 100 mm / min. Initial strength is 1 hour after room temperature after heat sealing,
The strength after aging is measured after standing the laminate in a 50 ° C. oven for 2 weeks or 3 months.

[0031]

Example 2 An ethylene copolymer (melt flow rate: 12 g / m) prepared by random copolymerization of 66% by weight of ethylene, 25% by weight of n-butyl acrylate, and 9% by weight of carbon monoxide.
10 minutes) in the same manner as in Example 1.

The results are shown in Table 1.

[0033]

Example 3 An ethylene copolymer (melt flow rate 12 g) obtained by random copolymerization of 60% by weight of ethylene, 27% by weight of n-butyl acrylate, and 13% by weight of carbon monoxide.
/ 10 min) was evaluated in the same manner as in Example 1.

Table 1 shows the results.

[0035]

Comparative Example 1 Ethylene-n-butyl acrylate of Example 1
Example 1 was repeated except that an ethylene-vinyl acetate copolymer (vinyl acetate content: 46% by weight, melt flow rate: 2.5 g / 10 min) was used instead of the carbon monoxide copolymer.

The results are shown in Table 1.

[0037]

Comparative Example 2 Ethylene-n-butyl acrylate of Example 1
Example 1 was repeated except that an ethylene-vinyl acetate copolymer (vinyl acetate content: 33% by weight, melt flow rate: 31 g / 10 min) was used instead of the carbon monoxide copolymer.

The results are shown in Table 1.

[0039]

Comparative Example 3 Ethylene-n-butyl acrylate of Example 1
Example 1 was repeated except that an ethylene-ethyl acrylate copolymer (ethyl acrylate content 35% by weight, melt flow rate 25 g / 10 minutes) was used instead of the carbon monoxide copolymer.

The results are shown in Table 1.

[0041]

Example 4 An ethylene copolymer (melt flow rate 6 g / m 2) obtained by random copolymerization of 60% by weight of ethylene, 30% by weight of n-butyl acrylate, and 10% by weight of carbon monoxide.
10 g) and 17 g of rosin ester (Tespol 1006 manufactured by Hitachi Chemical Co., Ltd.) are placed in a 200 ml Erlenmeyer flask and dissolved in 73 g of toluene. To this solution, 7 g of an isocyanate-based curing agent solution (Coronate L manufactured by Nippon Polyurethane Co., Ltd.) and 35 g of thinner as a diluting solvent were added to obtain a solution adhesive for print lamination.

This solution adhesive was evaluated for pot life and adhesive properties as described below. Table 2 shows the results. Pot life The above solution adhesive solution is allowed to stand at 40 ° C. in a safeven dryer, and the state of the solution after one day and three days is visually observed.
The symbols 〇 and × in Table 2 represent the following evaluations.

〇 --- No gelation or precipitation occurs. × --- Gelation and precipitation occur. Adhesion The above-mentioned solution adhesive solution is uniformly applied to a 200 μ-thick soft vinyl chloride (containing 60 parts by weight of diophthyl phthalate) film in a 5 μ-thickness, air-dried, and then kraft paper and a heated press roll at 80 ° C. Laminate under the condition of 3 kg / cm ² .

The obtained laminate is cut into strips having a width of 25 mm.
Peeling is performed at a tensile speed of 100 mm / min with a tensile tester, and the adhesion state is observed. After bonding, the initial adhesion is 23 ° C,
After 1 day at 50% relative humidity, the adhesion over time is 50
The laminate is evaluated after standing for 3 months in an oven. In addition,
The symbols 〇 and × in Table 2 represent the following evaluations.

〇 The kraft paper tears. ×---The soft vinyl chloride film and the kraft paper peel off.

[0046]

Comparative Example 4 Ethylene-n-butyl acrylate of Example 4
-Same as Example 4 except that an ethylene-vinyl acetate copolymer (vinyl acetate content 46% by weight, melt flow rate 2.5 g / 10 min) was used instead of the carbon monoxide copolymer.

Table 2 shows the results.

[0048]

Comparative Example 5 Ethylene-n-butyl acrylate of Example 4
-Instead of carbon monoxide copolymer, ethylene-ethyl acrylate copolymer (ethyl acrylate content 35% by weight,
The procedure was the same as in Example 4 except that a melt flow rate (25 g / 10 min) was used.

Table 2 shows the results.

[0050]

[Table 1]

[0051]

[Table 2]

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-181557 (JP, A) JP-A-61-183343 (JP, A) JP-A-59-168057 (JP, A) JP-A 64-64 43552 (JP, A) JP-A-50-34087 (JP, A) Patent 2965589 (JP, B2) JP-B-7-10968 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) ) C09J 173/00 C09J 123/08 C09J 133/06 C08L 73/00

Claims (3)

(57) [Claims] 1. [I] An ethylene, (meth) acrylic acid ester and carbon monoxide are copolymerized, and the component unit derived from ethylene is 40 to 92% by weight, (meth)
Component unit derived from an acrylate ester is 5 to 50
% By weight, and a component unit derived from carbon monoxide is 3
The ethylene / (meth) acrylate / carbon monoxide copolymer, which contains an ethylene / (meth) acrylate / carbon monoxide copolymer contained in an amount of about 20% by weight and a soluble solvent [II]. When the content of [I] is 1 to 5
0% by weight of a solution adhesive. 2. The method according to claim 1, wherein the soluble solvent contains at least one compound selected from the group consisting of aromatic hydrocarbons, cyclic ethers, ketones, halogenated hydrocarbons and acetates. Solution adhesive. 3. A printing lamination comprising the solution adhesive according to claim 1 or 2, wherein the adhesive is applied to at least one of a printed material and a resin film, and then the two are laminated and adhered. Adhesive for print lamination.