JPH0649390A - Polymerizable overprint varnish composition - Google Patents

Abstract

PURPOSE:To provide a polymerizable overprint varnish compsn. easily soluble in an aq. alkali soln. and capable of enhancing the efficiency of pulp recycle. CONSTITUTION:The compsn. comprises a compd. having at least one acid anhydride or carboxyl group and one (meth)acryloyl group per molecule, and a compd. having one (meth)acryloyl group and/or one vinyl group per molecule.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to polymerizable overprint varnishes. More specifically, the present invention relates to a polymerizable overprint varnish composition and an overprint varnish emulsion which are cured by irradiation with ultraviolet rays or electron beams and have a property that a resin film after curing is dissolved in alkali.

[0002]

2. Description of the Related Art Overprint varnish is applied and printed to protect the printing surface of paper, plastic film, etc., to improve blocking resistance, abrasion resistance, and scratch resistance, and at the same time to obtain high-gloss printed matter. It is a used coating agent. Specific examples of gloss processing are paperware, labels, stickers,
It can be found on record jackets, book covers, magazine covers and catalog covers, picture postcards, and glossy posters. Typical examples of gloss processing include so-called vinyl drawing, press coating, print laminating and the like. Furthermore, recently, various radiation-curable overprint varnishes of unsaturated polyester, epoxy acrylate, urethane acrylate, etc. have been used for the purpose of eliminating the complexity of these processing steps.

Nowadays, in the age of environmental protection, the reuse of resources has become a very serious social problem, and the problem of pulp recycling is particularly important from the viewpoint of greening resource protection. Has become. From this point of view, looking at the environment where the overprint varnish is placed, it is difficult to decompose the components such as the film laminated on paper and the conventional resin component cured by ultraviolet light, which is contrary to the original use and purpose. It must be said that it is an extremely negative material for the recycled use of pulp. In the recycling process of used paper, not only these resin components make recycling difficult but also the recovery rate of pulp is lowered at present.

[0004]

SUMMARY OF THE INVENTION There has been a demand for a polymerizable resin composition which can be decomposed by a simple treatment during pulp regeneration after processing and which does not impair the original characteristics of an overprint varnish.

[0005]

Means for Solving the Problems The present invention has been achieved as a result of intensive studies by the present inventors in order to improve the above-mentioned problems. That is, the present invention

(1) (A) a compound having one or more acid anhydride groups or carboxyl groups and one (meth) acryloyl group in one molecule, (B) one (meth) acryloyl group in one molecule, and And / or a polymerizable overprint varnish composition containing a compound having a vinyl group (2) A polymerizable overprint varnish characterized in that the composition according to (1) is dispersed and emulsified in water. Provide an emulsion.

The polymerizable overprint varnish composition of the present invention is cured by irradiation with ultraviolet rays or the like, and in the case of an emulsion, moisture is removed by heating and then cured by irradiation with ultraviolet rays, etc. It is soluble in.

The components constituting the polymerizable overprint varnish composition of the present invention will be described. One or more acid anhydride group or carboxyl group and one (meth) in one molecule
Examples of the compound (A) having an acryloyl group include the following. (1) a compound obtained by the reaction of a dibasic acid or / and its acid anhydride with a compound having one or more hydroxyl groups and one (meth) acryloyl group;
Specific examples of the dibasic acid and / or its acid anhydride include succinic acid, maleic acid, phthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, trimellitic acid, fumaric acid, and them. Acid anhydride, a copolymer of isobutylene and maleic anhydride,
Copolymer of methyl vinyl ether and maleic anhydride,
Examples thereof include a copolymer of indene and maleic anhydride, and specific examples of the compound having at least one hydroxyl group and one (meth) acryloyl group in one molecule include hydroxyl (meth) acrylate and hydroxylpropyl (meth). ) Acrylate, ε-caprolactone-β-hydroxyethyl (meth) acrylate adduct (manufactured by Daicel Chemical Industries, Ltd., Praxel FA-1, FM-1, FA-
2) etc. are mentioned. (2) A reaction product of a lactone and a compound having at least one hydroxyl group and at least one (meth) acryloyl group in one molecule; in this case, examples of the lactone include ε-caprolactone and valerolactone. (3) Compounds such as (meth) acrylic acid and its dimer acid

The compounds exemplified in the above (1) to (3) can be used alone or in admixture of two or more at any ratio. A preferable amount of (A) is 5 to 90% by weight, preferably 10 to 80% by weight in the composition of the present invention, and if the concentration is lower than 5% by weight, the solubility of the cured film in an alkaline aqueous solution tends to be insufficient. If it exceeds 90% by weight, the physical properties of the cured film tend to become brittle.

Specific examples of the compound (B) having one (meth) acryloyl group and / or vinyl group in one molecule include N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, ( (Meth) acrylamide, diacetone acrylamide, N-methylol (meth) acrylamide, acroylmorpholine, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, ε-caprolactone-β-hydroxyethyl (meth) acrylate, polyethylene glycol ( (Meth) acrylate, ethyl carbitol acrylate, acrylic acid-2-hydroxy-3-phenyloxypropyl, glycerol mono (meth) acrylate, phenoxyethyl acrylate, lauryl (meth)
Acrylate, phenoxy polyethylene glycol (meth) acrylate, glycerol mono (meth) acrylate, tetrahydrofurfuryl (meth) acrylate,
Examples thereof include acryloylmorpholine, dimethylaminoethyl (meth) acrylate, N-vinylpyrrolidone and the like.

These compounds (B) can be used alone or as a mixture of two or more kinds at any ratio. In order to increase the alkali solubility, it is preferable to use acrylamides among the above specific examples. The compound (B) is contained in the composition of the present invention in an amount of 5 to 70% by weight, preferably 10 to 60% by weight. If it is less than 5% by weight, the cured film tends to become brittle, and if it exceeds 70% by weight, an aqueous alkaline solution is used. Solubility in water tends to be insufficient.

The polymerizable overprint varnish composition of the present invention is prepared by mixing and stirring the above-mentioned components (A) and (B) at the ratios described above. In the polymerizable overprint varnish composition of the present invention, in addition to the above-mentioned components, a polymerization initiator, a polymerization inhibitor, an alkali solubility improver, a thickener, a leveling agent, a fluidity improver, and a defoaming agent may be added if necessary. Agents, so-called surface modifiers added to improve wear resistance and slip properties, and are low molecular weight polyethylene waxes, polymer waxes, or various silicone-based additives. The usage amount and type can be appropriately selected,
Generally, it is 0 to 15% by weight in OP (overprint) varnish.

When the polymerizable overprint varnish composition of the present invention is dispersed / emulsified in water and used in an emulsion composition, the emulsifying / dispersing agent includes polyoxyethylene alkyl ether, polyoxyethylene alcohol ether, polyoxyethylene. Nonionic surfactants such as alkyl phenyl ethers, polyoxyethylene derivatives, oxyethylene / oxypropylene block polymers, polyoxyethylene sorbitan fatty acid esters, polyethylene glycol fatty acid esters, fatty acid salts, alkyl sulfate ester salts, alkylbenzene sulfonates, alkyl Naphthalene sulfonate, alkyl sulfosuccinate, alkyl diphenyl ether disulphonate, alkyl phosphate, polyoxyethylene alkyl sulfate, naphthale Examples include emulsifiers and dispersants that are generally commercialized such as sulfonic acid formalin condensates, special polycarboxylic acid polymer surfactants, and anionic surfactants such as polyoxyethylene alkyl phosphates. Depending on the composition of the polymerizable overprint varnish composition to be dispersed, one type or several types may be selected and, if necessary, they may be used by mixing with an emulsifying / dispersing agent other than the above.

This emulsifying / dispersing agent is used in an emulsion.
It is usually contained in the range of 0.5 to 30% by weight, more preferably 1 to 20% by weight. If it is less than 0.5%, a stable emulsion cannot be obtained. On the contrary, if it exceeds 30% by weight, the physical properties of the cured film become brittle.

The emulsion of the present invention can be prepared by a generally known method. For example, the emulsifying / dispersing agent is usually dissolved or dispersed in water at a concentration of 0.5 to 30% by weight, and then the phase containing the polymerizable overprint varnish composition of the present invention is stirred at a low speed to carry out the emulsification / dispersion. A method of gradually adding an aqueous phase in which a dispersant is dissolved or dispersed in water, and emulsifying / dispersing using a high speed stirrer such as a homomixer and a sand mill or a microfluidizer can be used, but the method is not limited to this. Not a thing.

As a method for applying the polymerizable composition of the present invention, known means such as a roll coater, a gravure coater and a flexo coater can be applied. Further, the polymerizable composition of the present invention can be cured by irradiating it with ultraviolet rays from a high pressure mercury lamp, a metal halide lamp, a xenon lamp or the like by a conventional method. The thickness of the cured film is usually 1
-20 μm, preferably 1-5 μm.

[0017]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.
In addition, the part in an Example shows a weight part.

Synthesis Example 1 A 1 L reaction flask was charged with 100.1 g of succinic anhydride, 118.4 g of 2-hydroxyethyl acrylate and 0.11 g of hydroquinone monomethyl ether as a polymerization inhibitor all at once, and the mixture was gradually warmed while stirring. , 90 ± 5 ℃
And kept the reaction. The reaction was continued for about 15 hours to obtain 213.1 g of hydrogen-2-acryloyloxyethyl hydrogen succinate. Its viscosity is 204 cps at 25 ° C and acid value is 258 m.
It was gKOH / g.

Synthesis Example 2 In a 1 L reaction flask, 100.1 g of succinic anhydride, 132.8 g of 2-hydroxyethyl methacrylate, and 0.12 g of hydroquinone monomethyl ether as a polymerization inhibitor were added.
Was added at once and gradually warmed up with stirring to 90 ± 5
The reaction was kept at ℃. Continue the reaction for about 15 hours, and then 228.4 g of hydrogen-2-methacryloyloxyethyl hydrogen succinate.
Got Its viscosity is 220 cps at 25 ° C, acid value is 25
It was 0 mgKOH / g.

Synthetic Example 3 In a 1 L reaction flask, 100.1 g of succinic anhydride, acrylic acid-2-hydroxy-3-phenyloxypropyl (trade name, KAYARAD R-128, manufactured by Nippon Kayaku Co., Ltd.) 118.4 g, polymerization inhibition 0.16 g of hydroquinone monomethyl ether as an agent was charged all at once, and the temperature was gradually raised with stirring, and the reaction was continued at 90 ± 5 ° C. The reaction was continued for about 15 hours to give hydrogen acryloyloxymethyl-2-phenoxyethyl hydrogen succinate 316.2.
g was obtained. The viscosity was 11740 cps at 25 ° C., and the acid value was 172 mgKOH / g.

Synthesis Example 4 A 1 L reaction flask was charged with 148.1 g of phthalic anhydride, 118.4 g of 2-hydroxyethyl acrylate and 0.3 g of hydroquinone monomethyl ether as a polymerization inhibitor all at once, and gradually warmed with stirring. The reaction was maintained at 90 ± 5 ° C. The reaction was continued for about 18 hours to obtain 258.8 g of 2-acryloyloxyethyl hydrogen phthalate. Its viscosity is 4500 cps at 25 ° C, acid value is 209
It was mgKOH / g.

Synthesis Example 5 Hexahydrophthalic anhydride 154.
2 g, 2-hydroxyethyl acrylate 121.8
g, 0.14 g of hydroquinone monomethyl ether as a polymerization inhibitor were charged at once, and the temperature was gradually raised with stirring, and the reaction was maintained at 90 ± 5 ° C. The reaction was continued for about 18 hours to obtain 248.5 g of hydrogen-2-acryloyloxyethyl hydrogen hexahydrophthalate. Its viscosity is 3 at 25 ° C
The value was 350 cps and the acid value was 201 mgKOH / g.

Examples 1 to 5 Compounds (A) having one or more acid anhydride groups or carboxyl groups and one (meth) acryloyl group in one molecule obtained in each of the above synthesis examples, one in one molecule A compound (B) having a (meth) acryloyl group and / or a vinyl group,
Further, an overprint varnish was prepared by adding a photopolymerization initiator, an alkali solubility improver, and a slip agent as optional components according to the mixing ratios shown in Table 1, respectively. As for the method of preparation, each component shown in Table 1 was charged in a 1 L reaction flask at a scale of 1 Kg in total according to the compounding ratio of Table 1 and mixed at 80 ° C. for 1 hour to obtain the objective polymerizable composition of the present invention. . Then on the art paper No. 80 w / c using 3 bar coater
Ultraviolet rays of 500 mj / cm ² were irradiated using an m metal halide lamp (ASE-20 manufactured by Nippon Battery). When the coating film thus cured was evaluated, the results shown in Table 2 were obtained.

Examples 6 and 7 After producing a polymerizable varnish in the same manner as in Examples 1 to 5,
500 g of varnish was weighed in a 2 L container, 500 g of the emulsifier and water phases dissolved at the compounding ratio shown in Table 1 were gradually added under stirring with a homomixer, and after completion of the addition, the mixture was treated at a stirring speed of 5000 rpm for 10 minutes. The desired emulsion was obtained.
Then, it was prepared by coating with a bar coater on the art paper so that the film thickness after curing would be 5 μm, was applied, dried by hot air at 80 ° C. to remove water, and irradiated with ultraviolet rays in the same manner as in Examples 1 to 5. When the cured coating film was evaluated, the results shown in Table 2 were obtained.

Table 1 Example Comparative Example 1 2 3 4 5 6 7 1 2 3 Compound (A) Compound of Synthesis Example 1 43 30 30 21 40 30 40 40 Compound 10 of Synthesis Example 2 Compound 45 of Synthesis Example 3 45 45 Synthesis Compound of Example 4 46 47 Compound of Synthesis Example 5 5 Compound (B) 2-hydroxyethyl methacrylate 5 ethyl carbitol acrylate 22 30 14 36 15 30 14 30 30 Dimethyl acrylamide 9 12 Methacrylamide 13 9 5 5 10 5 Methoxyethyl Acrylate 42 Tripropylene glycol Diacrylate 10 10 Trimethylolpropane triacrylate 6 Dimethyl aminoethyl methacrylate 2 Other additives SMA resin 1000 (Note 1) 17 15 15 15 Slip-Aid SL-425 (Note 2) 1 1 1 Benzyldimethyl Ketal 5 5 5 5 5 5 5 5 5 5 Dispersant or emulsifier Pluronic F-68 (Note 3) 10 10 Perex RP Note 4) 10 water 95 90 90

(Note 1) Alkali solubility improver (ARCO CHE
Copolymer of styrene and maleic anhydride (MICAL) (Note 2) Slip improver (San Nopco) (Note 3) Emulsifier (Asahi Denka) Oxyethylene / oxypropylene block polymer (Note 4) Emulsifier ( Kao Co., Ltd.) phosphate ester surfactant

Comparative Examples 1 to 3 Overprint varnishes were prepared according to the compounding ratios shown in Table 1 and evaluated in the same manner as in Examples 1 to 5 and 6, 7 are shown in Table 2.

Table 2 Examples Comparative Examples 1 2 3 4 5 6 7 1 2 3 Viscosity (cps / 25 ° C) 420 32 245 60 210 320 16 Gloss 92 90 93 92 90 85 86 92 93 85 Flexibility ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Solubility 2 4 4 3 3 2 4 × × × * 1 * 1 * 1 * 1: Not dissolved even after 20 minutes.

Measurement and evaluation of various characteristic values of the composition and cured product were carried out by the following methods.

Viscosity The viscosity of the composition at 25 ° C. was measured using an E-type viscometer. Gloss The surface of the cured product was measured using a gloss checker (HORIBA, Ltd., gloss meter). Flexibility According to the JIS K5400 test method, the diameter of the mandrel is 10 m
A bending test was carried out using m, and those having no crack in the cured film were judged to be good. Alkali-soluble solubility (1): The cured film was immersed in a 3% aqueous solution of caustic soda, and the time until dissolution was measured.

As is apparent from the results shown in Table 2, the cured product obtained from the polymerizable composition of the present invention is excellent in gloss, flexibility and alkali solubility.

[0032]

EFFECTS OF THE INVENTION The polymerizable composition of the present invention has a cured film having excellent gloss and flexibility, and has a property of being soluble in an aqueous alkaline solution. Therefore, the polymerizable composition is suitable for an overprint varnish with improved recycling. .

Claims (2)

[Claims] 1. A compound having (A) one or more acid anhydride groups or carboxyl groups and one (meth) acryloyl group in one molecule, and (B) one (meth) acryloyl group in one molecule, and / or Alternatively, a polymerizable overprint varnish composition comprising a compound having a vinyl group. 2. A polymerizable overprint varnish emulsion in which the composition according to claim 1 is dispersed and emulsified in water.