POLYESTER RESIN, INK COMPOSITION FOR OFFSET PRINTING, PRINTED WORK, AND PRODUCTION METHOD FOR PRINTED WORK

Abstract

A polyester resin that is a condensation polymer of a polyol mixture including an epoxidized vegetable oil and a rosin additive, a polycarboxylic acid and a vegetable-derived polyol; has a mass ratio (rosin/epoxidized vegetable oil) between the rosin and the epoxidized vegetable oil of 2-10; and has a biomass content of at least 80%. The polyester resin has a high proportion of biomass-derived components and can be used to obtain an offset printing ink composition that has excellent scratch resistance and excellent abrasion resistance.

Claims

1. A polyester resin that is a polycondensation product of a polyol mixture (A) containing an adduct of an epoxidized vegetable oil and rosin, a polycarboxylic acid (B), and a plant-derived polyol (C), wherein a mass ratio (rosin/epoxidized vegetable oil) of the rosin to the epoxidized vegetable oil is 2 or more and 10 or less, and a biomass degree is 80% or more.

2. The polyester resin according to claim 1, wherein an acid value is 1 to 50 mg KOH/g.

3. The polyester resin according to claim 1, wherein a solubility parameter sp value by a turbidimetric titration method is 9.0 to 11.0 (cal/cm.sup.3).sup.1/2.

4. The polyester resin according to claim 1, wherein a weight average molecular weight is 25,000 to 60,000.

5. An ink composition for offset printing comprising the polyester resin according to claim 1.

6. The ink composition for offset printing according to claim 5, which is an active energy ray-curable type.

7. A printed work comprising a print layer formed from the ink composition for offset printing according to claim 5.

8. A production method for a printed work, the method comprising performing printing using the ink composition for offset printing according to claim 5.

9. An ink composition for offset printing comprising the polyester resin according to claim 2.

10. An ink composition for offset printing comprising the polyester resin according to claim 3.

11. An ink composition for offset printing comprising the polyester resin according to claim 4.

12. A printed work comprising a print layer formed from the ink composition for offset printing according to claim 9.

13. A printed work comprising a print layer formed from the ink composition for offset printing according to claim 10.

14. A printed work comprising a print layer formed from the ink composition for offset printing according to claim 11.

Description

EXAMPLES

[0081] Hereinafter, the present invention will be described with reference to Examples and the like, but the present invention is not limited thereto.

Example 1

<Production of Polyester Resin>

[0082] Into a reaction vessel with a stirrer, a reflux condenser, and a thermometer, 50 parts by mass of epoxidized soybean oil (manufactured by ADEKA CORPORATION, trade name: “0-130P”), 150 parts by mass of disproportionated rosin (manufactured by FUJIFILM Wako Pure Chemical Corporation, trade name: “dehydroabietic acid”, acid value: 136 mg KOH/g), and 0.5 part by mass of triphenylphosphine as a catalyst were charged, and the mixture was reacted at 180° C. for 5 hours to conduct an addition reaction, whereby a mixture containing a polyol (adduct) was prepared. Further, 10 parts by mass of 1,2-cyclohexene dicarboxylic acid was added thereto, the temperature of the mixture was raised to 250° C., heating was performed for 2 hours, then 10 parts by mass of glycerin was added thereto, the mixture was reacted at 250° C. for another 8 hours to conduct a polycondensation (dehydration condensation) reaction, whereby the polyester resin of Example 1 was produced. The obtained polyester resin had a weight average molecular weight of 35,000, an acid value of 7.6 mg KOH/g, a sp value of 9.10 by a turbidimetric titration method, and a biomass degree of 94.3%.

<Preparation of Ink Composition for Offset Printing>

[0083] Into a reaction vessel with a cooling tube, 80 parts by mass of the polyester resin obtained above, 19 parts by mass of ditrimethylolpropane triacrylate (DI-TMPTA), and 1 part by mass of butylhydroxytoluene (BHT) were charged, and heated and stirred at 100° C. for 1 hour to prepare a varnish. Subsequently, 70 parts by mass of the obtained varnish, 15 parts by mass of carbon black (manufactured by Mitsubishi Chemical Corporation, trade name: “#60”), 7 parts by mass of Irgacure 907 (manufactured by BASF SE), and 3 parts by mass of 4,4′-bis(diethylamino)benzophenone (EAB) were mixed together, and kneaded using a three-roll mill at a roll temperature of 40° C. until the particle size became 5.0 μm or less, 5 parts by mass of trimethylolpropane triacrylate (TMPTA) was added thereto, whereby an active energy ray-curable ink composition for offset printing was prepared.

<Creation of Printed Work>

[0084] On aurora coated paper, 0.1 cc of the ink composition for offset printing obtained above was spread using an RI color developing machine (2-split roll, manufactured by Meishin Seisakusho Co., Ltd.), and immediately irradiated with ultraviolet rays (metal halide lamp, irradiation quantity: 36 mJ/cm.sup.2), whereby a printed work was created.

Examples 2 to 10 and Comparative Examples 1 to 6

[0085] The same operation as in Example 1 was carried out except that the raw materials of the polyester resins used in the respective Examples and Comparative Example were changed to the raw materials and mixed amounts presented in Table 1, whereby the polyester resins of the respective Examples and Comparative Examples were produced, then ink compositions for offset printing were prepared, and printed works were created.

[0086] The respective items of the printed works obtained above were evaluated according to the following evaluation methods. The results are presented in Table 1.

[Scratch Resistance]

[0087] The printed coating film of the printed work was rubbed with a nail, and the number of rubbing times until the coating film was scraped was evaluated according to the following criteria.

[0088] 5: Coating film is not scraped by 10 times of rubbing.

[0089] 4: Coating film is scraped by 8 to 9 times of rubbing.

[0090] 3: Coating film is scraped by 5 to 7 times of rubbing.

[0091] 2: Coating film is scraped by 2 to 4 times of rubbing.

[0092] 1: Coating film is scraped by 1 time of rubbing.

[Abrasion Resistance]

[0093] The printed coating film of the printed work was tested using a taber type abrasion tester (manufactured by YASUDA SEIKI SEISAKUSHO, LTD.) under the test conditions (500 g×10 times, cushioning paper: aurora coated paper), and the residual ratio of the printed coating film after the test was visually evaluated according to the following criteria.

[0094] 5: Coating film is not removed.

[0095] 4: Coating film is slightly removed.

[0096] 3: About half of coating film is removed.

[0097] 2: Coating film is mostly removed.

[0098] 1: Coating film is completely removed.

TABLE-US-00001 TABLE 1 Biomass Example degree 1 2 3 4 5 6 7 8 Polyester Polyol Epoxidized Epoxidized  95% 50 30 50 50 50 50 50 resin mixture vegetable oil soybean oil (A) Epoxidized  95% 50 linseed oil Epoxy Bisphenol A  0% compound type epoxy resin Rosin Dis- 100% 150 150 150 150 150 150 150 proportionated rosin Polymerized 100% 150 rosin Carboxy- Stearic acid  0% containing compound Polycarboxylic 1,2-Cyclohexene-  0% 10 10 10 10 10 10 5 30 acid (B) dicarboxylic acid Plant-derived Glycerin 100% 10 10 10 10 10 10 polyol (C) 1,3-Propanediol 100% 10 1,4-Butanediol 100% 10 Rosin/epoxidized 3 5 3 3 3 3 3 3 vegetable oil (mass ratio) Weight average molecular 3.5 3.3 3.4 4.5 3.4 3.2 3.2 4.3 weight (×10.sup.4) Acid value (mg KOH/g) 7.6 7.5 7.5 6.5 7.5 7.4 7.4 23 sp value 9.10 9.09 9.12 9.09 9.13 9.12 9.12 9.30 Biomass degree 94.3% 94.3% 94.3% 94.3% 94.3% 94.3% 96.5% 86.5% Evaluation Scratch resistance 5 5 5 5 5 5 5 5 Abrasion resistance 5 5 5 5 5 5 5 5 Biomass Example Comparative Example degree 9 10 1 2 3 4 5 6 Polyester Polyol Epoxidized Epoxidized  95% 50 50 50 100 150 50 50 resin mixture vegetable oil soybean oil (A) Epoxidized  95% linseed oil Epoxy Bisphenol A  0% 50 compound type epoxy resin Rosin Dis- 100% 150 150 150 100 50 150 150 proportionated rosin Polymerized 100% rosin Carboxy- Stearic acid  0% 150 containing compound Polycarboxylic 1,2-Cyclohexene-  0% 10 10 10 10 10 10 10 acid (B) dicarboxylic acid Plant-derived Glycerin 100% 5 30 10 10 10 10 polyol (C) 1,3-Propanediol 100% 1,4-Butanediol 100% Rosin/epoxidized 3 3 3 — 1 0.3 3 3 vegetable oil (mass ratio) Weight average molecular 3.3 3.2 3.2 0.9 2.1 0.9 0.5 0.8 weight (×10.sup.4) Acid value (mg KOH/g) 8.7 2.1 6.7 9.2 8.6 3.2 35 43 sp value 9.12 9.25 9.08 8.99 9.12 9.02 9.01 9.12 Biomass degree 94.2% 94.8% 72.7% 26.1% 93.2% 92.0% 98.8% 94.0% Evaluation Scratch resistance 5 5 5 1 2 1 1 1 Abrasion resistance 5 5 5 1 2 1 1 1