JP2896203B2 - Printing ink - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a printing ink. More specifically, the present invention relates to a printing ink having excellent sticking property, drying property, and It relates to a printing ink that provides gloss and film strength.

(Prior Art) Conventionally, a varnish for offset printing ink has been obtained by dissolving a rosin-modified phenolic resin and an alkyd resin in a drying oil and / or a semi-drying oil, and producing an aliphatic and / or aromatic high-boiling petroleum. It is adjusted by adding a solvent.
Although the sticking properties of the ink using such a varnish, that is, the setting and drying rates, depend on the rate of penetration and / or evaporation of the solvent into the printing medium and the rate of the film formation of the oxidative polymerization of the drying oil. The latter is the rate-determining stage.

Reducing the drying oil and / or semi-drying oil speeds up the setting and increases the drying speed on the permeable substrate (eg on paper). Therefore, the rod stackability is improved.

However, these have good wettability with the pigment which is a coloring material,
In addition to increasing the fluidity of the ink and improving the gloss of the printed matter, it also plays a role in imparting film strength to the printed surface, so that the amount used cannot be extremely reduced.

Substitutes for drying oils have been studied so far, and JP-A-53-98385 discloses copolymers of isobutyl methacrylate, isobornyl methacrylate and methacrylic acid.

JP-B-62-28830 discloses a resinous copolymer comprising a vinyl aromatic hydrocarbon, an ester of rosin alcohol and acrylic acid or methacrylic acid, or an α-β-unsaturated carboxylic acid. No. 23509 describes a maleic anhydride / styrene copolymer modified with an unsaturated alcohol.

However, in all of these, the wettability with the pigment is inferior to the drying oil or the semidrying oil, and the setting and drying are accelerated, but the gloss is insufficient, and the film strength, especially the scratch resistance, is deteriorated. In Japanese Patent Publication No. 1-251010, an ester of a polyhydric alcohol having a valency of 4 or more and an unsaturated fatty acid is used as a substitute for a drying oil.

This has the same function as the drying oil as a component, and aims at the effect of accelerating the drying property by increasing the molecular weight. Therefore, the setting is delayed, and it does not work favorably for the rod product.

(Problems to be Solved by the Invention) An object of the present invention is to provide a printing ink which improves the above-mentioned various drawbacks, is excellent in stickiness and drying properties, and provides a printed matter having high gloss and film strength. I do.

[Configuration of the invention]

(Means for Solving the Problems) The present invention comprises an oil-modified phenol resin obtained by reacting 60 to 95 parts by weight of an unsaturated oil with 5 to 40 parts by weight of a phenol resin. Printing ink.

The unsaturated oils used in the present invention include tung oil, linseed oil, soybean oil, tall oil, sesame oil, rapeseed oil, cottonseed oil, eno oil,
Natural oils such as euticica oil and safflower oil, and conventionally known unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid, eleostearic acid and abietic acid and polyhydric alcohols such as glycerin, diglycerin and triglycerin And pentaerythritol, dipentaerythritol and unsaturated fatty acid esters, and synthetic oils in which some or all of the double bonds of an acetylene-conjugated diene copolymer are rearranged to a conjugated diene structure. One or more of these unsaturated oils are reacted with a phenolic resin.

A phenol resin is a phenol such as p-cresol, p-tert.butylphenol, p-tert.amylphenol, p-octylphenol, p-phenylphenol, p-cyclohexylphenol, bisphenol A and formaldehyde, or an acid catalyst. Refers to an oil-soluble phenol resin reacted with an alkali catalyst.

Heretofore, phenolic resins modified with natural oils have been used in coatings, and their coatings are known to be fast drying and provide excellent water resistance, weather resistance and chemical resistance. However, these are usually poorly soluble and are soluble only in low-boiling parent solvents such as xylene, toluene, and mineral spirits. Therefore, printing inks mainly composed of aliphatic solvents having an aniline point of 65 ° C or more and a boiling point of 200 ° C or more are mainly used. Was not used.

The present invention relates to a phenol resin modified with an unsaturated oil having a weight average molecular weight of 3,000 to 15,000 and an aliphatic high boiling point solvent (boiling point range 276 to 313 ° C., aniline point 70 ° C.) 10 g.
If the solution obtained by heating and melting 0 g does not cause cloudiness at 25 ° C., it can be sufficiently used for printing inks, and by limiting the weight ratio of unsaturated oil to phenol resin to 60 to 95 to 5 to 40, The present invention has been completed based on the finding that the above required performance can be satisfied.

As a method for obtaining a phenol resin modified with an unsaturated oil, any method known in the art, for example, described in Japanese Patent Publication No. 45-20507, 61-367 can be used.

The printing ink comprises, in addition to the oil-modified phenol resin and the solvent according to the present invention, if necessary, conventionally used rosin-modified phenol resin and additives such as a gelling agent. When a resin such as a rosin-modified phenol resin is used in combination, the oil-modified phenol resin /
The weight ratio of rosin-modified phenolic resin / solvent is usually 5 to 5.
40 / 10-70 / 30-70. When a resin such as a rosin-modified phenolic resin is not used in combination, the weight ratio of the oil-modified phenolic resin / solvent according to the present invention is usually 60 to 90/10 to 40.
It is.

Hereinafter, the present invention will be described with reference to examples. In the examples, “parts” means “parts by weight” and “%” means “% by weight”.

Example 1 221 g of p-phenylphenol and 100 g of xylene were placed in a flask, and heated and stirred under an N ₂ gas flow of 300 cm ³ / hour.
At 40 ° C., 40 g of p-formaldehyde and 15 g of a 10 wt% hydrochloric acid aqueous solution are added. The mixture is further heated and reacted at 130 ° C. for 3 hours, and then the phenol resin is taken out. In a flask, put 200 g of resin, 360 g of tung oil and 65 g of linseed oil, and react under heating and stirring at 220 ° C. for 2 hours while recovering xylene and water under an N ₂ gas flow of 300 cm ³ / hour, and react with the mixture for 2 hours. 14,000 oil-modified phenolic resins were obtained. 10 g of this resin was heated and melted in 10 g of No. 5 solvent (manufactured by Nippon Oil Co., Ltd.) and cooled to 25 ° C., but no cloudiness was produced.

The oil-modified phenolic resin 100 parts of the rosin-modified phenolic resin Tamanoru 358 (manufactured by Arakawa Chemical) 400 parts of No. 5 solvent 400 parts by N ₂ gas stream of the ALCH1.2 parts 300 cm ³ / time, stirring 195 The temperature was raised to ° C. and kept for 1 hour to prepare a varnish for printing ink.

Example 2 An oil-modified phenol (weight average molecular weight: 10200, 10 g of this resin) was heated and melted in 10 g of No. 5 solvent (Nippon Oil) obtained under the same conditions as in Example 1 except that 265 g of p-octylphenol was used as phenol. And then cooled to 25 ° C., and did not become turbid.)

Comparative Example 1 A varnish was prepared under the same conditions as in Example 1 except that 100 parts of N / B linseed oil (Nisshin Oil Co., Ltd.) was used instead of 100 parts of oil-modified phenol.

Comparative Example 2 90 g of dipentaerythritol, 560 g of linseed oil fatty acid, and 2 g of p-toluenesulfonic acid were placed in a flask, and N ₂ gas was supplied at 300 cm ³ /
Dehydration reaction was carried out for 2 hours while refluxing xylene at 180 ° C. to 200 ° C., and 100 parts of an ester of a polyhydric alcohol and an unsaturated fatty acid obtained by removing xylene under reduced pressure were added to 100 parts of the oil-modified phenol of Example 1. Instead, varnishing was performed under the same conditions as in Example 1.

These varnishes were kneaded with a three-roll mill at the following proportions to prepare printing inks, and a performance test was performed.

* Ink tack value (Toyo Seiki Incometer) is 1
0.5 ± 0.3 The flow value of the ink (radius mm / 1 minute value measured by a spread meter manufactured by Toyo Seisakusho) was adjusted to 18.5 ± 0.3.

Performance test and results 1. First, 0.3cc of ink was spread on art paper by RI tester (manufactured by Akira Seisakusho Co., Ltd.), and then 24 hours at 20 ° C and 65% RH.
Let dry for hours.

1-1 Gloss: The above printed matter was measured with Murakami Color Gloss Meter GM26D (60
{-60}).

1-2 Coating strength: The printed matter was cut into 5 cm widths, rubbed 40 times using a Sutherland Lab tester under a load of 2 pounds, and the printed matters were visually evaluated for rub-off and scratch resistance.

○: good △: acceptable 2. Drying time (on paper): 0.15 cc of ink was spread on art paper with the above-mentioned RI and tester 6-part rolls, and a paper was placed on it and applied to the Chaoyangkai drying tester for exhibition. The time until the colored ink did not transfer to the contacting paper was measured.

Drying time (on-machine): The ink was drawn to a thickness of 75 μm on a tin plate, left in an oven at 40 ° C., and the time during which the ink did not adhere to the fingertip was determined by finger touch determination.

3. Set time: 0.2cc of ink is spread on art paper by the above-mentioned RI tester four-part roll, then the exhibition color is divided every time, and from the exhibition color to another art paper using the RI tester roller. The degree of adhesion of the ink was observed, and the time (minute) until the ink did not adhere was measured.

4. Stackability: 20,000 sheets were stacked on a SK coated paper with a printing ink at a printing speed of 6000 rph without spraying powder using a Heidel GTO printing machine. At room temperature, the concentration of the solid portion was controlled to be constant.

 After printing, the backing of the printed material was visually evaluated.

：: good Δ: acceptable ×: unacceptable Test results are shown in Table 1.

[Effects of the Invention] According to the present invention, it is possible to obtain a printing ink which has a high setting and drying speed, has a good stacking property, and gives a printed matter having excellent gloss and film strength.

Claims (2)

(57) [Claims] 1. A printing ink comprising an oil-modified phenolic resin obtained by reacting 60 to 95 parts by weight of an unsaturated oil with 5 to 40 parts by weight of a phenolic resin. 2. The printing ink according to claim 1, further comprising a rosin-modified phenol resin.