JPS61185575A - Composition for electron ray curing - Google Patents

Abstract

PURPOSE:The titled composition useful as an undercoat for metallized paper, providing coated paper having improved water-vapor resistance and evenness, comprising plural specific unsaturated compounds containing (meth)acrylic acid residue at both ends of molecule. CONSTITUTION:(A) A compound (e.g., formula II, etc.) shown by the formula I (n is 1-5; R1, R2, and R3 are H, or CH3) is blended with (B) a compound (e.g., formula IV, etc.) shown by the formula III (a+b is 0-8; R4, R5, R6, and R7 are H, or CH3) and/or (C) a compound (e.g., formula VI, etc.) shown by the formula V(c+d is 0-8; R8 and R9 are H, or CH3) in a weight ratio of the component A:B and/or C of preferably 20:80-80:20, to give the aimed compo sition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an electron beam curable composition for undercoating metallized paper.

(Conventional technology) Traditionally, aluminum metal paper was made from a laminate of aluminum foil and paper, but as the price of aluminum rose, a technology that required only a small amount of aluminum was gradually developed, i.e., vapor deposition of aluminum onto paper. The technology to do this is being researched and is gradually being industrialized. However, when aluminum is deposited directly onto a piece of paper, the surface of the paper is rough, so when the aluminum atoms crystallize during deposition, the roughness of the paper appears, making it impossible to arrange the metal smoothly. Can't get shine. Therefore, it is necessary to pre-treat the paper in advance to give it smoothness. Furthermore, if the aluminum metal paper is intended to be moisture resistant, the aluminum layer of the vapor-deposited paper is usually about 500A and is an extremely thin film, so the layer coated on the paper in advance is required to have excellent moisture resistance. Therefore, the manufacturing technology of metallized paper depends on the technology of forming an undercoat layer (undercoat layer) with excellent smoothness and moisture resistance.

Known examples of undercoat layers on metallized paper include a method of coating paper with an aqueous polymer latex and drying it to form a film, as shown in JP-A-59-21794 and JP-A-59-21795; A method using a polymer dissolved in a solvent, or JP-A-56-6818
There are methods such as electron beam curing using a polymerizable liquid composition as shown in No. 6.

(Problems to be Solved by the Invention) However, each of these methods has drawbacks and is not fully satisfactory. For example, the method of coating paper with water-based polymer latex and drying it to form a film has problems with moisture resistance, and the method of using a polymer dissolved in an organic solvent requires a long organic solvent drying process. It requires time, has low production efficiency, and uses a large amount of energy, and since many solvents are flammable and have an adverse effect on the human body, there is a risk of fire and pollution. Furthermore, with regard to the electron beam curing method using a polymerizable liquid composition, currently it has excellent moisture resistance and surface smoothness, has an appropriate viscosity for coating, has good electron beam curability, and does not cause paper warpage. (Undercoat resins shrink during curing, so there is a strategy to select a resin that shrinks as little as possible.) There is no undercoat composition yet that satisfies all of the following points, such as slow penetration into paper.

(Means for Solving the Problems) As a result of intensive studies aimed at solving all of the above problems, the present inventors have found that electron beam curing for undercoating of metal-deposited paper such as aluminum, which has well-balanced properties and does not have the above-mentioned drawbacks. The present invention was completed by discovering a composition for use in this field.

The present invention relates to a compound I represented by the general formula (Il, where n has a value of 1 to 5, and R+, & and R3 each independently represent hydrogen or a methyl group). and/or compound (III) represented by the general formula (III) (wherein a+b has a value of 0 to 8, and R4, R5, R6 and the mountain each independently represent a hydrogen or methyl group) ( (In the formula, c + d has a value of 0 to 8, and Rs and crest each independently represent a hydrogen or methyl group.) For electron beam curing for undercoating of metallized paper The present invention relates to a composition.

As mentioned above, the composition of the present invention contains Compound I and Compound (2), Compound (2) and Compound (2), or all three of Compound I, Compound (2), and Compound (2).

In Compound I, n takes a value of 1 to 5, and when n exceeds 5, the viscosity of the composition becomes high, making it difficult to coat paper, and the electron beam curing speed also slows down, resulting in a decrease in moisture resistance. The preferred value of n is 1-3.

Examples of preferable compounds I include the following.

For compound II, when the value of a exceeds 8, the electron beam curing speed becomes slow. Preferably, the value of a + b is 2 to 5
It is.

Examples of preferable compounds (1) include the following.

When the value of c+d exceeds 8 in compound (2), the electron beam curing speed and moisture resistance decrease. The preferred straightness of C1d is O~2
It is.

Examples of preferable compounds (1) include the following.

Compound ■ In the composition of the present invention, the ratio of (compound ■) and (compound ■ and/or compound ■) used is 20:8 by weight.
The range of 0 to 80:20 is preferable.

The composition of the present invention may contain other polyfunctional acrylates in addition to Compound I, Compound (1), and Compound (2). Other polyfunctional acrylates include trifunctional or higher functional acrylates such as trimethylolpropane triacrylate, dipentaerythritol hexaacrylate, pentaerythritol triacrylate, and pentaerythritol tetraacrylate. The amount of these other polyfunctional acrylates used is 20% of the total weight of the composition of the present invention.
% or less, particularly preferably 10% or less.

In addition, in order to further improve flexibility and moisture resistance, saturated polymers such as polyethylene, polyvinyl chloride, polyacrylate, and polyvinylidene chloride with a molecular weight of 10,000 to 1,000
000 molecular weight and epoxy compounds such as bisphenols may be added as components of the compositions of the present invention. In this case, the amount added is preferably 20% or less of the total weight of the composition of the present invention.

The composition of the present invention is prepared by mixing the components.

Priming (coating) of paper with the composition of the invention,
Curing of the composition by electron beam irradiation and vacuum deposition of metal such as aluminum can be performed by known conventional methods.

For example, the method for undercoating the paper may be any known method such as roll coating, offset coating, spray coating, knife coating, etc. The thickness of the coating film on paper is preferably about 1 to 10μ.

Curing by electron beam irradiation is, for example, 0.1 to 30 Mrad.
irradiation with an electron beam.

Vacuum deposition of a metal such as aluminum may be carried out in a conventional manner at +6°C, and preferably the metal film thickness is 200-100 OA at 10-10 mmHg.

Metals to be vapor-deposited include, in addition to aluminum, tin, nickel, gold, silver, zinc, chromium, copper, and the like.

(Example) Example 1 In a 200 cc flask, 50% of the compound (a) was added. ,
Compound (F') at 50? In addition, at 90-100℃
After stirring for a minute, the mixture was allowed to stand at 50 to 60°C for 30 minutes to degas, and then left to stand at room temperature. The resulting composition was coated on paper to a thickness of about 4μ using an R,I tester, and
- Irradiated with 10 Mrad using a curtain-type electron beam irradiator manufactured by 1 company. Half of the cured coated paper was used for moisture permeability measurement (JIS standard, Z 0208.40°C, relative humidity 90%), and the other half was coated with aluminum so that the aluminum film thickness was 500A at 5 x 10 mmHg. was vacuum-deposited and the moisture permeability of the vapor-deposited paper was measured in the same manner. Result is.

It was as follows.

Moisture permeability of coated paper 300 ft1m” 2
4 hrs Moisture permeability of vaporized paper 20 P/rr
Xe 24 hrs Examples 2 to 11° Experiments similar to those in Example 1 were conducted using the compositions shown in Table 1. The results are shown in Table-1.

In the table, (5) to Ll indicate the above-mentioned compound position to compound pile, respectively. M has the general formula (n = 3 in Il, R
The common name is Epicote 1001 epoxy acrylate, where 1 and R2 are methyl groups and R3 is hydrogen.

DPCA-20 is a trade name manufactured by Nippon Kayaku ■ and is a caprolactone-modified acrylate of dipentaerythritol.

HX-220 is a trade name of Nippon Kayaku Corporation and is a caprolactone-modified diacrylate of hydroxypivalic acid ester neopentyl glycol.

TMPTA stands for trimethylolpropane triacrylate.

Epicote 828 is the trade name of Yuka shell epoxy ■.
It is an epoxidized product of bisphenol A.

Epicoat 1001 is the trade name of Yuka Shell Epoxy (2) and is an epoxidized product of bisphenol A.

Furthermore, in Examples 1-11, the composition had a viscosity suitable for coating on paper, so coating was extremely easy.

Furthermore, the electron beam curability of the composition was good, no warping of the coated paper was observed, and the surface of the coated paper was finished extremely smooth. Moreover, the obtained vapor-deposited paper was smooth and had a beautiful metallic luster. The adhesion to aluminum coated paper was also excellent.

(Effects of the invention) When using the composition of the present invention, there is no need to use a solvent, so there is no need for a solvent recovery device, there is no fear of fire or pollution, and the production speed of metallized paper is improved, making it economical. A manufacturing system can be set up. Furthermore, since the composition of the present invention has a suitable viscosity, it is easy to apply the composition to paper. In addition, the composition has good electron beam curability, and the applied composition can be cured by electron beam irradiation in an extremely short time of 10-1 to 10-2 seconds, so it is difficult for one composition to penetrate into paper. The composition is well coated on one sheet of paper, and smoothness can be imparted to the surface of the paper. When the composition of the present invention is used, coated paper with no warpage, excellent moisture resistance, and smoothness can be obtained. Therefore, the vapor-deposited paper obtained also has excellent moisture resistance and a beautiful metallic luster. Furthermore, it has excellent adhesion to aluminum coated paper.

Claims (1)

[Claims] 1 A compound represented by the general formula (I), ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, n is a value of 1 to 5, R_1, R_2 and R_3
each independently represents hydrogen or a methyl group. ) Compounds represented by general formula (II) and/or compounds represented by general formula (III) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (II) (In the formula, a + b is a value of 0 to 8, R_4, R_5, R_
6 and R_7 each independently represent hydrogen or a methyl group. ) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(III) (In the formula, c+d is a value of 0 to 8, and R_8 and R_9 each independently represent a hydrogen or methyl group.) An electron beam curing composition for undercoating metallized paper.