JPS5947215A - Production of resin for printing ink - Google Patents

Abstract

PURPOSE:To obtain a resin for printing inks capable of greatly improving the luster of the final printed matter and suitable for use in offset printing inks, by copolymerizing a vinyl monomer with a modified drying or semi-drying oil having a specified polymerizable unsaturated groups. CONSTITUTION:A vinyl monomer containing a glycidyl group is reacted with a carboxylated drying and/or semi-drying oils. By the above reaction, a modified drying and/or semi-drying oils containing a polymerizable unsaturated group are obtained, and these oils are copolymerized with a vinyl monomer in the subsequent process to obtain a desired printing ink resin. It is preferable that the polymerizable unsaturated groups in the above modified oils are present in an amount of 5-100mg-equivalent per 100g of the above modified oil. The copolymerization ratio used in the copolymerization of the modified drying and semi- drying coils containing a polymerizable unsaturated group with a vinyl monomer is 1:1-1:10 by weight, and the copolymerization is carried out preferably by solution polymerization at 150-200 deg.C in a high-boiling aliphatic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing a resin for printing ink, and particularly to a method for producing a resin for printing ink suitable for use in offset inks containing petroleum solvents.

Conventionally, as resins for offset printing inks, petroleum resins, alkyd resins, phenolic resins, and the like have been used in addition to rosin-based resins represented by rosin-modified phenolic resins. These resins are generally dissolved in a drying oil such as linseed oil and a high-boiling petroleum solvent to form a vehicle, and then pigments and other additives are added to form a printing ink. It is also used as an overprint fest without adding pigment.

Since printing inks and overprint surfaces using these resins are generally used for high-quality printed matter, it is particularly required that the printed matter have excellent gloss.

However, there is a limit to the gloss of printed matter obtained by applying printing inks or overprint faces using the above-mentioned conventional resins, and there has been a strong desire to develop resins for printing inks that provide a high degree of gloss.

In recent years, resins for printing inks made of vinyl polymers as resins for heat-set offset inks (US Pat. No. 4,327,011) and resins for printing inks made of non-aqueous dispersions containing vinyl polymers (Japanese Patent Application Laid-open No. 57-1993) have been developed. −
No. 55976) was proposed, but although these resins may be able to achieve new improvements in heat set inks, they do not contribute at all to improving the gloss of printed matter and do not satisfy the above requirements. It was impossible to force him to do so.

The object of the present invention, made in view of the above-mentioned current situation, is to obtain a novel resin for printing ink that can significantly improve the gloss of final printed matter.

As a result of intensive research with the above purpose in mind, the present inventors have discovered a modified drying oil having a polymerizable unsaturated group obtained by reacting a vinyl monomer having a glycidyl group with a carboxylated drying oil and/or semi-drying oil. It has been found that by copolymerizing a modified semi-drying oil and a vinyl monomer, a resin for printing ink can be obtained which can provide printed matter with extremely high gloss when used in printing ink applications. , is an optical realization of the present invention.

Examples of drying oils or semi-drying oils that can be used in the present invention include linseed oil, tung oil, eno oil, soybean oil, cottonseed oil, sesame oil, and dehydrated castor oil. These can be used alone or in combination of two or more. Carboxylation of drying oils and/or semi-drying oils can be easily carried out by addition reaction of α,β unsaturated carboxylic acids or their anhydrides according to conventional methods. As mentioned above, starting materials for the present invention include:
Among various vegetable oils, both drying oil and semi-drying oil can be used, and they can also be used in combination, but in terms of drying properties, it is better to use drying oil alone. It is permitted to use it. In this specification, it is expressed as "drying oil and/or semi-drying oil" in this sense.

Examples of vinyl monomers having a lycidyl group used in the present invention include glycidyl acrylate, glycidyl methacrylate, aryl glycidyl ether, and vinyl glycidyl ether.

The reaction between a carboxylated drying oil and/or semi-drying oil and a vinyl monomer having a glycidyl group is an esterification reaction between a carboxyl group and a glycidyl group, and it is an esterification reaction between a carboxyl group and a glycidyl group. This can be easily carried out by heating in the presence or absence of an esterification catalyst.

The above reaction yields a modified drying oil and/or modified semi-drying oil (hereinafter simply referred to as modified oil) having a polymerizable unsaturated group, which is subjected to copolymerization with a vinyl monomer in the next step. The polymerizable unsaturated group in the above modified oil is 100g of the modified oil.
It is preferable that the amount is 5 to 100 rv equivalent per unit. If it is less than 5 da equivalent, the copolymerizability with the vinyl monomer in the next step will be insufficient, and the object of the present invention cannot be achieved. , problems such as excessive thickening and generation of insoluble gels occur.

In the present invention, specific examples of the vinyl photoheavy material co-electrically charged with the modified oil include aromatic vinyl monomers such as styrene, α-methylstyrene, and vinyltoluene, methyl (meth)acrylate, ( meth)ethyl acrylate, butinope (meth)acrylate, isobutyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, etc. (meth)acrylic acid esters, vinyl esters such as vinyl acetate and vinyl propionate, alkyl vinyl ethers, (meth)acrylonitrile, (meth)acrylamide and its N-alkylated products, (meth)acrylic acid, crotonic acid, maleic Acids, fumaric acid, etc. can be mentioned. In particular, it is preferable to use styrene, vinyltoluene, and various (meth)acrylic esters. These vinyl monomers may be used alone or in combination of two or more. In particular, styrene 65 to 85% of the total weight of the vinyl monomer used
Weight%, (meth)acrylic acid ester 15-35% by weight
It is preferable to use a mixed monomer consisting of 0 to 20% by weight of other vinyl monomers, since a printing ink resin capable of exhibiting particularly excellent gloss is obtained.

The copolymerization of the modified oil and the vinyl monomer may be carried out according to generally known polymerization methods, such as bulk polymerization, solution polymerization, emulsion polymerization, etc., but if the weight average molecular weight of the resulting resin is 4000. A polymerization method that provides a molecular weight of 25,000 to 25,000 is desirable, and in this respect, a solution polymerization method is particularly preferred. When the molecular weight of the resin is outside the above range, when used in printing ink applications, the fluidity, transferability, pigment dispersibility, etc. of the ink are likely to deteriorate, causing problems. Any polymerization solvent in solution polymerization can be used as long as it can dissolve or disperse the resulting resin, but when using a high boiling point aliphatic (petroleum-based) solvent known as a printing ink solvent, Solution polymerization is possible at 150 to 200°C under normal pressure,
Furthermore, the obtained resin solution is particularly preferable in that it can be used as it is as a vehicle for printing ink.

The copolymerization ratio of modified oil and vinyl monomer may be changed arbitrarily depending on the use and purpose of the vinyl monomer and resin used, but in general, modified oil IM Dobe It is preferable that the proportion of the vinyl monomer is 1 to 10 parts by weight. If the above ratio is less than 1 part by weight of the vinyl monomer per 1 part by weight of the modified oil, the melting point of the copolymer will be extremely lowered and the drying properties of the ink will be extremely poor.

On the other hand, if the amount of the vinyl monomer exceeds 10 parts by weight, the copolymer's solubility in petroleum solvents decreases and the gloss of the ink deteriorates.

The novel resin for printing ink obtained by the method of the present invention having the above-mentioned structure has a drying oil and/or semi-drying oil structure based on a modified oil in the vinyl polymer chain, so that it is not suitable for petroleum-based printing inks. It has excellent solubility in solvents and can be highly differentiated into resins with low viscosity. In addition, according to this method, the content of styrene units can be increased, so that it can be used for printing ink to provide high-gloss printed matter, and is also excellent in economical efficiency. In addition, the printing ink resin obtained by the method of the present invention has excellent compatibility with various conventionally known offset ink resins, so it can be used in combination with various resins depending on the purpose for printing. It is capable of modifying ink.

Hereinafter, the present invention will be specifically explained based on Examples and Comparative Examples.

Preparation example of modified oil (preparation of carboxylated linseed oil) Linseed oil 1.000! v-maleic anhydride 50? was charged into a reaction vessel, heated to 200-205°C, and reacted at the same temperature until substantially all of the maleic anhydride was reacted to obtain carboxylated linseed oil.

Example 1 100 parts of the carboxylated linseed oil obtained in the above preparation example, 1 part of glycidyl methacrylate, and 4 parts of a high-boiling point petroleum solvent [Nisseki No. 5 Solvent manufactured by Nippon Oil Co., Ltd.] ioo, r,
The mixture was charged into a two-way flask and reacted at 90 to 95°C for 2 hours to obtain a modified linseed oil solution having polymerizable unsaturated groups. This modified linseed oil has 7.0 Tv equivalents of polymerizable unsaturated groups per 100y. Next, the temperature was raised to 190 to 200°C, and styrene 133y-, isobutyl methacrylate 614, and methacrylate 6? were added under a nitrogen gas flow. A mixed monomer consisting of 1 and 4 parts of di-1-butyl peroxide was added dropwise over 2 hours.

After the dropwise addition was completed, the same temperature was maintained for another 4 hours to complete the copolymerization reaction.

The resulting resin solution has a viscosity of 72,600 cps/25°0
It is a pale yellow transparent solution, and the average molecular weight of the resin is G
The result of measurement using the PC method was 9800.

Example 2 Modified linseed oil was prepared by reacting in the same manner as in Example 1 using carboxylated linseed oil 50/1 obtained in the above preparation example, glycidyl methacrylate 1 and high boiling point petroleum solvent (Shiraishi No. 5 Turben) 15CI. A solution was obtained. This modified linseed oil has an equivalent of 13.81 ng/100 polymerizable unsaturated groups. Thereafter, a copolymerization reaction was carried out in the same manner as in Example 1 to obtain a pale yellow transparent resin bath Q having a viscosity of 24,800 cps/25°C. The weight average molecular weight of the resin was 6,800.

Example 3 30 parts of carboxylated linseed oil obtained in the above preparation example, 1 part of glycidyl methacrylate. and high boiling point petroleum solvent (Shiraishi No. 5 Turben) l 170? and reacted in the same manner as in Example 1 to obtain a modified linseed oil solution. This modified linseed oil has 22.7 equivalents of polymerizable unsaturated groups per 100y. Thereafter, a copolymerization reaction was carried out in the same manner as in Example 1 to obtain a pale yellow translucent resin solution with a viscosity of 16,000 cps/25"C. The weight average molecular weight of the resin was 6,000.

Example 4 Carboxylated linseed oil obtained in the above preparation example r00? , glycidyl methacrylate 1y- and high-boiling petroleum solvent (
Four pieces of 8 stone No. 5 solvent) 100y- were charged into a flask and reacted at 90 to 95°0 for 2 hours to obtain a modified linseed oil solution having polymerizable unsaturated groups.

Then, the temperature was raised to 190 to 200"0, and under a nitrogen gas flow, styrene 162!f, isobutyl methacrylate 30?, methyl methacrylate 2!?, methacrylic acid 6 and di-t were added.
2 mixed monomers consisting of -butyl peroxide 4y-
It was dripped over time. After the dropwise addition was completed, the same temperature was further maintained for 4 hours to complete the copolymerization reaction.

The resulting resin solution was a pale yellow transparent solution with a viscosity of 50,000 cps/25°C, and the weight average molecular weight of the resin was 820.
It was 0.

Comparative Example 1 Four high-boiling point petroleum solvents (Shiraishi No. 5 Turben) 20p were placed in a flask and heated under a nitrogen gas stream to 190~2
The temperature was raised to 00°C. Next is styrene 133? , isobutyl methacrylate 61y-, methacrylic acid 6no and di-
T-butyl peroxide 4! ? A mixed monomer consisting of the following was added dropwise over a total of 2 hours. After the dropwise addition was completed, the temperature was maintained for another 4 hours to complete the polymerization reaction. The obtained styrene-acrylic resin solution was a white dispersion with a viscosity of 3500 cps/25°0, and separated into two layers after standing. The weight average molecular weight of this styrene-acrylic polymer was 1,400.

Comparative Example 2 Resin for commercially available offset ink (rosin modified phenolic resin 1300?, linseed oil 15 (1, Shiraishi No. 5 Truben)
150f was mixed and dissolved by heating at 200°0 for 30 minutes to obtain a rosin resin solution.

Comparative Example 3 100 g of commercially available offset ink resin (rosin-modified phenolic resin) was mixed with a high boiling point petroleum solvent (Shiraishi No. 5 Truben)
) was dissolved at 110 iP and heated to 160°C. Next, a mixed monomer consisting of 10 styrene, 5 y-isobutyl acrylate, and 1 y-t-butyl peroxide was added dropwise to the mixture over a period of 2 hours under a nitrogen gas flow. After the dripping is finished,
The polymerization reaction was further maintained at the same temperature for 4 hours to complete the polymerization reaction. The resin bath solution served had a viscosity of 35,000 cps/25°0.

Test Examples 120 g of each resin solution of Examples 1 to 4 and Comparative Examples 1 to 3, pigment (carmine 6B130?) and cobalt naphthenate (metal content 8%, 12.1 cc) were mixed and kneaded with a three-roll roll to produce a red color. An offset ink was prepared.

Each ink was spread on art paper using an R1 tester, and the gloss was determined with the naked eye and with a glossmeter (60° incident angle). The results are shown in the table below.

Ashiko Chemical Industry Co., Ltd. Agent Ashi 1) Naoe

Claims (1)

[Scope of Claims] 1) Modified drying oil and/or modified semi-drying oil having a polymerizable unsaturated group obtained by reacting a carboxylated drying oil and/or semi-drying oil with a vinyl monomer having a glycidyl group. A method for producing a resin for printing ink, characterized by copolymerizing oil and a vinyl monomer. 2) The copolymerization ratio of the modified drying oil and/or modified semi-drying oil having a polymerizable unsaturated group and the vinyl monomer is 1:1 to 1:10 (weight ratio). A method for producing a resin for printing ink according to scope 1. 3) The modified semi-drying oil and/or modified semi-drying oil having a polymerizable unsaturated group is the modified semi-drying oil and/or modified semi-drying oil 100
3. The method for producing a printing ink resin according to claim 1 or 2, which contains 5 to 1 oorn9 equivalents of polymerizable unsaturated groups per resin. 4) Copolymerization of a vinyl monomer with a modified drying oil and/or a modified semi-drying oil having a polymerizable unsaturated group is carried out at a temperature of 150 to 200°C in a high boiling point aliphatic solvent. 4. A method for producing a resin for printing ink according to any one of claims 1 to 3, which comprises carrying out solution polymerization.