JP2003292553A - Resin for offset printing ink and method of producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin for offset printing ink that can give the performance equal to or higher than that of conventional rosin-modified phenol resin in no use of alkylphenol and formaldehyde. <P>SOLUTION: A polymeric rosin (a), C5 petroleum resin (b), unsaturated dibasic acid (c), polyhydric alcohol (d) and polyfunctional acrylate are allowed to react with one another to obtain the resin for offset printing ink having a softening point of 120-220°C and a weight-average molecular weight of 20,000-300,000. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a commercial offset ink used for printing posters, calendars, leaflets, catalogs and the like, a resin for offset ink used in newspapers, and a method for producing the same.

[0002]

2. Description of the Related Art As a resin for offset ink, a rosin-modified phenolic resin obtained by reacting a rosin, a polyhydric alcohol and a phenolic resin has been used.
The rosin-modified phenolic resin is further modified according to the purpose by adding a polymerized rosin, an unsaturated dibasic acid, a vegetable oil, a petroleum resin, or the like, but it has also been modified for some time, but the basic rosin, Polyhydric alcohols and phenolic resins have become essential constituent materials.

As the rosin, gum rosin, tall rosin and wood rosin having different raw materials sources, and rosins from China, Indonesia, Vietnam, the United States and Argentina, which have different producing regions, have been used according to their purposes. As the polyhydric alcohol, glycerin, pentaerythritol, dipentaerythritol, etc. have been used properly according to the purpose. Similarly, as the phenol resin, a bisphenol A type or an alkylphenol type resol resin such as p-t-butylphenol, p-octylphenol, nonylphenol or dodecylphenol has been used according to the purpose.

[0004]

[Problems to be Solved by the Invention] The rosin-modified phenolic resin has been praised for offset inks as it gives excellent ink performance. However, its constituent materials, bisphenol A and alkylphenol, are endocrine disrupters (external endocrine disruptors). Suspicion of (disrupting chemical substances) has been suspected and their effects on the environment and organisms are still being investigated. Formaldehyde, which is a constituent of phenolic resins, has a problem of odor and its harmfulness, and is being eliminated in many fields such as paints and adhesives.

In view of this situation, the inventors of the present invention have conducted extensive studies, and as a result, by adopting DCPD petroleum resin and polyfunctional acrylate as constituent materials of the resin, bisphenol A and alkylphenol, which are suspected of being endocrine disrupters, are used. The present invention has been completed by finding that a new resin having a performance equal to or higher than that of a conventional rosin-modified phenolic resin can be obtained without using a formaldehyde, which has a problem of odor or harmfulness, even without using Came to let.

[0006]

[Means for Solving the Problems] That is, the present invention relates to a polymerized rosin (a), a DCPD petroleum resin (b), an unsaturated dibasic acid (c), a polyhydric alcohol (d), and a polyfunctional acrylate ( (E) The softening point obtained by reacting
20 ° C to weight average molecular weight of 20,000 to 300,000
0 resin for offset ink. The present invention also relates to a manufacturing method for synthesizing this resin by a specific method.

In the present invention, the polymerized rosin (a) is produced by dimerizing rosin with a catalyst such as sulfuric acid and, if necessary, removing unreacted rosin by a method such as distillation. The raw material can be produced by itself, or a commercially available product may be used. The softening point of the polymerized rosin is approximately 80 to 140 ° C., and the dimerization rate is approximately 2
It is 0 to 80%. The softening point and the dimerization rate of the polymerized rosin can be adjusted by adding rosin to the polymerized rosin.

In the present invention, DCPD petroleum resin (b)
Any known material can be used, for example, Marukarez M-510, M-52 manufactured by Maruzen Petrochemical Co., Ltd.
5A, M-890A, M-845A, Nippon Zeon Co., Ltd.
Quinton 1325, 1345, 1500, 1525
L, 1700 and the like. In addition, DCP
The D-based petroleum resin is preferably approximately 1 to 50 parts by mass per 100 parts by mass of polymerized rosin (including rosin added for adjusting the softening point and the dimerization rate, hereinafter abbreviated to include rosin). When the DCPD petroleum resin is blended, not only the misting resistance of the ink can be improved but also the emulsification rate of the ink can be reduced.

In the present invention, the unsaturated dibasic acid (c) is
Any conventionally known compound can be used as long as it reacts with the unsaturated bond of rosin, for example, maleic anhydride,
Maleic acid, fumaric acid, etc. can be mentioned. The unsaturated dibasic acid is a polymerized rosin (including rosin) 1
About 0.5 to 10 parts by mass per 100 parts by mass is desirable, and within this range, it is easy to set the softening point and the weight average molecular weight of the resin in the desired range.

In the present invention, the polyhydric alcohol (d) is
Conventionally known ones are used, for example, ethylene glycol, diethylene glycol, butanediol, 2-methylpentanediol, hexanediol, neopentyl glycol, glycerin, trimethylolpropane,
Examples thereof include dimethylolpropionic acid, trimethylolethane, pentaerythritol, and dipentaerythritol. The polyhydric alcohol is preferably approximately 5 to 15 parts by mass per 100 parts by mass of the polymerized rosin (including rosin). Within this range, the softening point and the weight average molecular weight of the resin are within the desired range. Easy to pay.

In the present invention, polyfunctional acrylate (e)
The conventionally known one is used, for example, ethylene glycol diacrylate, neopentyl glycol diacrylate, hexanediol diacrylate, trimethylolpropane diacrylate, trimethylolpropane triacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, Examples thereof include pentaerythritol tetraacrylate. The polyfunctional acrylate is approximately 0.1 to 20 per 100 parts by mass of polymerized rosin (including rosin).
It is desirable to use parts by weight. Within this range, the softening point and weight average molecular weight of the resin can easily be set within the desired range.

In the present invention, the softening point of the resin is 120 to
It must be 220 ° C. If the softening point is lower than 120 ° C, the ink setting and drying properties will be poor. Also,
When the softening point is higher than 220 ° C, it becomes difficult to prepare the varnish for ink. The measuring method of the softening point in the present invention is based on the ring and ball method described in JIS K2207.

In the present invention, the weight average molecular weight of the resin is 2
It should be between 30,000 and 300,000. When the weight average molecular weight is less than 20,000, it is difficult to obtain the elasticity required for the ink varnish, and the misting resistance of the ink is poor. On the other hand, when it is 300,000 or more, it is difficult to obtain the viscosity required for the ink varnish, and the fluidity of the ink is poor. The weight average molecular weight in the present invention is measured by gel permeation chromatography and is a value converted into the molecular weight of monodisperse standard polystyrene.

The resin for offset ink in the present invention includes polymerized rosin (a), DCPD petroleum resin (b), unsaturated dibasic acid (c), polyhydric alcohol (d), and polyfunctional acrylate (e). Besides, if desired, for example, gum rosin, tall rosin, vegetable oil, polymerized vegetable oil, vegetable oil fatty acid, ester of vegetable oil fatty acid, alkyd resin, DC
A petroleum resin other than PD is added to cause a reaction, and a softening point,
It is also possible to adjust the molecular weight, solubility, viscosity and the like.

The resin for offset ink in the present invention is obtained by first reacting a polymerized rosin (a), a DCPD petroleum resin (b), an unsaturated dibasic acid (c), and a polyfunctional acrylate (e), and then reacting the same. It can be produced by reacting a reaction product with a polyhydric alcohol (d). Further, the polymerized rosin (a), the DCPD petroleum resin (b), the unsaturated dibasic acid (c), and the polyhydric alcohol (d) are first reacted,
Then, the reaction product may be reacted with a polyfunctional acrylate (e) to produce the product. However, the resin produced by the latter method is not only suitable as a resin for ink because the proportion of polyfunctional acrylate self-polymerizing is small and a minute gel-like substance is not formed, and the softening point of the resin Also, it has an advantage that it is easy to set the weight average molecular weight within a desired range.

In the case of the former synthesis, polymerized rosin, DCPD
System petroleum resin, unsaturated dibasic acid, and polyfunctional acrylate are charged into a reactor and reacted at a temperature of 150 to 250 ° C.,
Then, the reaction mixture was charged with a polyhydric alcohol and the temperature was adjusted to 20.
React at 0-280 ° C. In the latter case, polymerized rosin,
DCPD-based petroleum resin, unsaturated dibasic acid, and polyhydric alcohol were charged into a reactor and reacted at a temperature of 200 to 280 ° C., and then a polyfunctional acrylate was charged to this reaction product,
The reaction is carried out at a temperature of 150 to 250 ° C. The esterification reaction may be uncatalyzed, for example, by adding a suitable catalyst such as a metal-based catalyst such as calcium oxide, magnesium oxide, zinc oxide or zinc acetate, or a non-metal-based catalyst such as phosphoric acid or p-toluenesulfonic acid. It can also be reacted. Further, in order to remove the condensed water, a suitable reflux solvent such as xylene can be added and reacted.

[0017]

The present invention will be described in detail below with reference to examples. In addition, the charged part represents a mass part.

Synthesis Example 1 720 parts of polymerized rosin (softening point 140 ° C., dimerization rate 80%), 240 parts of Chinese gum rosin, Quinton 1345 (DCPD manufactured by Nippon Zeon Co., Ltd.) in a reaction vessel equipped with a stirrer and a water separator. Petroleum resin) 60 parts, polymerized linseed oil 1
Charge 20 parts, heat and stir while blowing nitrogen gas, and react 60 parts of maleic anhydride at 200 ° C., then add 125 parts of pentaerythritol and 1.2 parts of magnesium oxide, dehydration-condensate at 270 ° C. to obtain an acid value. The reaction was continued until it reached about 20. Then, 12 parts of 1.6-hexanediol diacrylate was reacted at 230 ° C. to obtain (resin 1).

Comparative Synthesis Example 1 Polymerized rosin (softening point 14
720 parts of 0 ° C, dimerization rate of 80%), 300 parts of Chinese gum rosin, 120 parts of polymerized linseed oil were charged, heated and stirred while blowing nitrogen gas, and reacted with 60 parts of maleic anhydride at 200 ° C, then pentaerythritol. 135
And 1.2 parts of magnesium oxide were charged, and the mixture was dehydrated and condensed at 270 ° C. and reacted until the acid value became about 20. Then 2
1.6-hexanediol diacrylate 12 at 30 ° C
Parts were reacted to obtain (resin 2).

Comparative Synthesis Example 2 Chinese gum rosin 900 was placed in the same reaction vessel as in Synthesis Example 1.
Charge 20 parts and stir with heating while blowing nitrogen gas.
After reacting 15 parts of maleic anhydride at 0 ° C, 230 ° C
Nonylphenol-based resol-type phenol resin 540
Parts were added dropwise over 3 hours. Then, 95 parts of glycerin and 0.9 part of magnesium oxide were charged, and dehydration condensation was performed at 270 ° C. to react until the acid value became about 20, to obtain (resin 3).
The nonylphenol-based resol-type phenol resin was added to the same reaction container as in Example 1 in the same manner as nonylphenol 100.
0 part and 300 parts of paraformaldehyde (purity 92%) were charged, heated and stirred, and 10 g of a 10% sodium hydroxide aqueous solution was added as a catalyst at 80 ° C., and then the mixture was kept at 90 ° C. for 4 hours for synthesis.

With respect to the obtained resin, in addition to the measurement of the softening point and the acid value, the falling ball viscosity of the linseed oil varnish, the solubility in the ink solvent (AF7 solvent manufactured by Mitsubishi Nisseki Co., Ltd.) and the weight average molecular weight were measured. evaluated. The measurement was performed by the following method, and the results are summarized in Table 1.

Flaxseed oil varnish viscosity: Resin and flaxseed oil were mixed in a mass ratio of 1: 2, and the mixture was heated and melted and measured with a falling ball viscometer.

Solubility in solvent for ink (AF7 solvent solubility): It means the maximum amount of AF7 solvent which can exist without clouding when the resin is dissolved in AF7 solvent and left at 25 ° C. Resin 1 at the time
It is indicated by the amount of solvent of AF No. 7 converted per g.

Weight average molecular weight: The molecular weight (in terms of polystyrene) was measured by GPC analysis.

[0025]

[Table 1]

[0026]

For each resin in Table 1, resin 40 parts, soybean oil 20
Part, and AF7 solvent 40 parts were charged into a reaction vessel, and the temperature was increased with stirring while blowing nitrogen gas, and the temperature was kept at 200 ° C. for 1 hour to obtain a varnish. When this was cooled to 100 ° C., 1 part of ALCH-50 (manufactured by Kawaken Fine Chemical Co., Ltd.) was added as a gelling agent, and the temperature was raised to 180 ° C. and then 1
After keeping the temperature for a while, a gel varnish was obtained.

Next, 60 parts of gel varnish was added to Carmine 6B18.
Parts are kneaded with a three-roll mill, and each gel varnish and AF7 are used so that the tack is 6 to 7 and the flow is 25 to 28.
A red ink for test was obtained by adjusting with No. solvent.

[0028]

[Table 2] shows properties of each ink and evaluation results. The tack and flow were measured using a digital incometer (manufactured by Toyo Seiki Seisakusho, Ltd.) and a parallel plate viscometer (manufactured by Toyo Seiki Seisakusho, Ltd.), respectively.

[0029]

[Table 2]

[0030]

Ink performance evaluations shown in Table 2 were performed as follows.

Gloss: After 0.3 cc of ink was spread on an art paper with an RI tester (manufactured by Akira Seisakusho Co., Ltd.), it was dried in a hot air dryer at 120 ° C. for 5 seconds, and a gloss meter was measured at room temperature for 24 hours. The 60 ° specular reflectance was measured using (Gardner).

Emulsification rate: Using Lithotronic (manufactured by Novocontrol), 25 g of ink and 2 m of ion-exchanged water
The emulsion was added dropwise at a rate of 1 / min to measure the emulsification rate when saturated.

Amount of misting: When 1.3 cc of ink was rotated at 2000 revolutions per minute for 1 minute with a digital incometer (manufactured by Toyo Seiki Seisaku-sho, Ltd.), the amount of mist scattered below the roll was precisely weighed.

[0034]

From Table 2, it can be seen that the ink using resin 1 is
It is superior in emulsification resistance and misting resistance to an ink prepared in the same manner using PD-based petroleum resin-free) or Resin 3 (conventional rosin-modified phenolic resin). Also, resin 1
The ink using is different from the ink using resin 3,
It is clear that it does not contain potentially harmful alkylphenols or formaldehyde.

[0035]

INDUSTRIAL APPLICABILITY The resin for offset printing ink of the present invention does not use bisphenol A or alkylphenol, which is suspected to be an endocrine disrupter (exogenous endocrine disrupting chemical), and has a problem of odor and harmfulness. It is synthesized without using formaldehyde. Moreover, the resin properties can be easily adjusted to the same resin properties as those of the conventional rosin-modified phenolic resin, and an ink having the same performance as that of the conventional rosin-modified phenolic resin can be obtained with the same formulation.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kimikatsu Kitaya             Hitachi, 3-8-40 Kitadanomiya, Tokushima City, Tokushima Prefecture             Kasei Polymer Co., Ltd. Tokushima factory F term (reference) 4J026 AA08 AC31 BA28 CA02 CA03                       GA06                 4J039 AB08 AD10 AD13 AD18 AD21                       DA00 EA45 GA02

Claims (2)

[Claims] 1. A softening obtained by reacting a polymerized rosin (a), a DCPD-based petroleum resin (b), an unsaturated dibasic acid (c), a polyhydric alcohol (d), and a polyfunctional acrylate (e). Resin for offset ink having a point of 120 to 220 ° C. and a weight average molecular weight of 20,000 to 300,000 2. A polymerized rosin (a), a DCPD petroleum resin (b), an unsaturated dibasic acid (c), and a polyhydric alcohol (d) are first reacted, and then the reaction product is reacted with a polyfunctional acrylate (f). The method for producing a resin for offset ink according to claim 1, wherein