JPH0737506B2 - Printing ink resin and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION “Object of the Invention” (Field of Industrial Application) The present invention relates to a printing ink resin that gives a printing ink having good printability in offset printing.

(Prior Art) It is common to use a rosin-modified phenolic resin as a resin for offset printing inks, and its manufacturing method is to react a resol-type phenolic resin with a double bond of rosin without a catalyst, and then add glycerin or A method of esterifying the carboxyl group of rosin with a polyol such as pentaerythritol to reduce the acid value to 40 or less, or an acid value of 40 or less through an esterification reaction with rosin and a polyol such as glycerin or pentaerythritol, and then a resol-type phenol resin To react with the double bond of rosin ester without using a catalyst, rosin, phenol and formaldehyde are charged into a reaction kettle and reacted with the double bond of rosin at the same time as the formation of resol type phenol resin under alkaline catalyst, Furthermore, glycerin, pentaerythritol, etc. Polyol acid number by esterification reaction has been obtained by lowering the 40 or less with.

Since the acid value can be easily reduced to 40 or less by any of these three methods, it is general to set the OH / COOH ratio to 1/1 or more. Therefore, hydrophilic alcoholic hydroxyl groups remain in the rosin-modified phenolic resin thus obtained. This alcoholic hydroxyl group increases the emulsified amount of dampening water during the offset printing process, causes deterioration of fluidity, and causes water loss of the ink.

On the other hand, a resin for a printing ink, which reduces the acid value by esterifying a rosin and a resol-type phenol resin without using glycerin or pentaerythritol, is disclosed in JP-A-2004-242242.
No. 59-191776. However, although the solubility of this resin is very good, the molecular weight does not increase, so it is necessary to improve the molecular weight by using polybasic acids such as polymerized rosin, maleated rosin, and fumarized rosin that are used in combination with rosin as the carboxylic acid component. was there. The combined use of these polybasic acids had the adverse effect of increasing the cost of the resin.

(Problems to be Solved by the Invention) In offset printing, there has been a demand for a printing ink resin that has good printability and does not increase the cost.

[Structure of the Invention] (Means for Solving Problems) The present inventors have found that the rosin-modified phenolic resin is inexpensive, and can control the molecular weight suitable for the ink for offset printing, and has good printability for offset printing. The present invention has been reached as a result of studying the synthesis of

That is, the first invention of the present application is obtained by reacting a reaction component obtained by reacting a resol-type phenol resin and rosin without a catalyst with a resole-type phenol resin and / or a novolac-type phenol resin and a rosin under an acidic catalyst. A resin for a printing ink, which is a rosin-modified phenolic resin having an acid value of 40 or less containing a reactive component, and a second invention is 100 parts by weight of a rosin and a phenolic resin.
A rosin-modified phenolic resin obtained by reacting 0 to 150 parts by weight, the first step of reacting a rosin and a resole-type phenolic resin in the absence of a catalyst, and a weight relative to the resole-type phenolic resin used in the first step. The present invention relates to a method for producing a printing ink resin, which comprises a second step in which a resole-type phenol resin and / or a novolac-type phenol resin having a ratio of 0.8 to 4 and an acidic catalyst are added and reacted until the acid value becomes 40 or less.

In the present invention, in the reaction of the resol-type phenol resin and the rosin without a catalyst, the resol-type phenol resin reacts with the double bond present in the rosin to form a resin-like polybasic acid (mainly dibasic acid). To be done.

In addition, when the resol type phenol resin or novolac type phenol resin and rosin are reacted under an acidic catalyst, an esterified product of carboxylic acid of rosin is produced.

Examples of rosin include gum rosin, wood rosin, tall oil rosin, disproportionated rosin, etc. Also, combined use of rosin derivatives such as polymerized rosin, maleated rosin, fumarized rosin, C6-18 fatty acids, and polymerized dry oil fatty acids Is also possible if necessary.

The phenol resin used in the present invention is pt-butylphenol or p-butylphenol regardless of whether it is a resol type or novolac type.
Phenolic resins obtained by condensation of phenol with p-formaldehyde mainly containing at least one selected from octylphenol and p-nonylphenol are preferable. Of course, other phenols can be used. For the resol type condensate, alkali such as sodium hydroxide, potassium hydroxide, calcium hydroxide and magnesium oxide, ammonia water, amines such as 1-ethylamine, triethanolamine and triethylenediamine can be used as reaction catalysts. it can.

Further, known reaction catalysts such as sulfuric acid, hydrochloric acid, oxalic acid and p-toluenesulfonic acid can be used for the synthesis of the novolak type condensate.

Next, the weight ratio of the rosin and the phenol resin of the rosin-modified phenol resin of the present invention is preferably 30 to 150 phenol resin to 100 rosin. If the amount of phenolic resin is less than this range, the molecular weight of the resin will decrease and the softening point will also decrease. If it exceeds 150, the molecular weight becomes high, and as a result, the solubility in the ink solvent deteriorates.
Further, the ratio of the phenol resin reacted with the rosin in the present invention is such that the ratio of the phenol resin which reacts with the double bond of the rosin without a catalyst and the phenol resin which is esterified with the carboxylic acid in the presence of an acidic catalyst is 1: 0.8 by weight. ~ 1: 4 is desirable. If the amount of phenolic resin that reacts with the rosin double bond without catalyst is more than this range, the hydroxyl groups required for esterification will be insufficient, making it difficult to reduce the acid value and requiring a separate esterification step. , Offset printability is insufficient. On the other hand, when the amount is less than this range, the production of crosslinkable resinous polybasic acid is reduced and the molecular weight is lowered.

The acid value of the resin indicates the residual amount of free carboxyl groups, and if the residual amount is large, it is not preferable for offset printing suitability, and it is necessary to react until the acid value becomes 40 or less, preferably 30 or less.

To obtain the rosin-modified phenol resin of the present invention, p-
Sulfonic acids such as toluene sulfonic acid, dodecylbenzene sulfonic acid, methane sulfonic acid, ethane sulfonic acid,
Esterification reaction between rosin and resole-type or novolac-type phenolic resin is required by heating above 150 ℃ using mineral acids such as sulfuric acid and hydrochloric acid as catalysts. However, since the reaction product is easily colored under such conditions, it is preferable to use a reducing agent such as hypophosphorous acid, triphenyl phosphite or triphenyl phosphate in combination.

The reaction sequence of the rosin and the phenolic resin is such that the double bond in the rosin molecule is first reacted with the resol type phenolic resin without catalyst, and then an acid catalyst is added to the resol type and / or novolac type phenolic resin to react with the carboxyl group of the rosin. Method, the carboxyl group of rosin is first reacted with a resole-type or novolak-type phenol resin under an acidic catalyst to neutralize the acid catalyst, and then a resole-type phenol resin is added to react with the double bond. It is also possible to do so.

However, the step (1) requires an alkaline substance for catalyst neutralization, and the step (1) is more advantageous because it leaves a salt due to neutralization.

Further, the use of a hydrophilic polyol such as glycerin or pentaerythritol in the resin of the present invention is not so preferable, but the equivalent of the hydroxyl group to the carboxyl group is 0.6.
If the amount is within the equivalent range, the possibility that residual hydrophilic hydroxyl groups will remain due to the reaction of the acid value of the completed rosin-modified phenolic resin to 40 or less is very small, and no problem is found in offset printing suitability.

Further, the resin for a printing ink of the present invention is a rosin-modified phenol resin, a alkyd resin, a petroleum resin, which has been conventionally used for printing inks, and a high melting point, highly soluble rosin-modified phenol obtained by an esterification reaction of rosin and a phenol resin. It is possible to use it in combination with a resin, modify some of the petroleum resin, or modify it with acrylic.

In order to make a varnish for printing ink using the resin of the present invention, 50 to 150 parts by weight of a solvent and / or a drying oil (or a modified oil such as a polymerized oil or a drying oil alkyd resin) is added to 100 parts by weight of the resin of the present invention. Dissolves in parts by weight. In actual use, it is desirable to use a known gelling agent such as aluminum octylate, aluminum stearate, zirconium octylate, aluminum triisopropoxide, and aluminum diisopropoxide monoacetyl acetate to form a gel varnish. Also, as a colorant, pigments such as yellow, crimson, indigo, or black are dispersed, and if necessary, compounds such as an anti-friction agent, an ink dryer and a drying inhibitor are added to adjust the viscosity to an appropriate level. By doing so, it becomes an offset ink such as sheet-fed offset ink and offset wheel ink.

It can also be used as newspaper ink or letterpress ink. Furthermore, in order to make a varnish for gravure or flexo ink using the resin of the present invention, to 100 parts by weight of the resin of the present invention,
Aliphatic and alicyclic hydrocarbons having a boiling point of 140 ° C. or less at normal pressure may be dissolved in 100 to 200 parts by weight.

The present invention will be described below with reference to specific examples. "Part", "%"
Represents parts by weight and% by weight, respectively.

Production Example 1 (Production of Resol-Type Phenolic Resin) Stirrer, reflux condenser with water separator, 170 parts of p-octylphenol, 22 parts of pt-butylphenol, 170 parts of 35% formalin in a four-necked flask equipped with a thermometer, After adding 12 parts of 93% sodium hydroxide and 100 parts of tap water and heating to 90 ° C and reacting for 4 hours, 200 parts of toluene was added to dissolve the phenol resin in toluene, and 25 parts of 6N hydrochloric acid was added to 200 parts of tap water. The mixture was diluted with 1 part and added to neutralize, then allowed to stand, the aqueous layer was removed, and then washed with 200 parts of water twice to make PH 5 to 6, and then the toluene layer was collected. The toluene solution of this phenol resin has a nonvolatile content of 50%
The yield was 420. This resol type phenol resin solution is referred to as A resol solution.

Production Example 2 Phenol components (170 parts of p-octylphenol, 22 parts of pt-butylphenol) were added in the steps shown in Production Example 1.
In the same manner as above, except that the amount of octylphenol was changed to 200 parts, 400 parts of a resole type phenol resin solution (B resole solution) having a nonvolatile content of 49% was obtained.

Production Example 3 (Production of Novolac Phenolic Resin) A flask similar to that shown in Production Example 1 was charged with 170 parts of p-octylphenol, 22 parts of pt-butylphenol, 60 parts of 35% formalin, and 2 parts of oxalic acid. 90 after heating to 90 ° C
After reacting for 5 minutes, add 5 parts of hydrochloric acid and stir for 120 minutes at 90 ℃ to add 200 parts of water.
After adding 20 parts for 20 minutes, the mixture was left for 1 hour. Then, remove water, add 200 parts of water again, stir for 20 minutes, leave for 30 minutes to remove water, add 180 parts of xylene, and then add 2 parts at 110 ° C.
After stirring for an hour, a novolak liquid A having a nonvolatile content of 50% was obtained.

Production Example 4 In the process shown in Production Example 3, the phenol component (p-octylphenol 170 parts, pt-butylphenol 22 parts) was added to p.
A B novolak solution having a nonvolatile content of 45% was obtained by the same steps except that the amount of -t-butylphenol was changed to 200 parts.

Example 1 (Manufacture of ink resin having good offset printing suitability) Agitator, condenser with water separator, four-neck flask with thermometer were charged with 200 parts of Chinese gum rosin, heated while blowing nitrogen gas, and heated to 200 ° C. Melt, stir and heat up to 260 ℃ below. 120 parts of B resol solution was added dropwise over 1 hour, during which toluene in the resol solution was collected through a condenser with a water separator and the temperature was kept at 260 ° C. After that, the mixture is stirred at 260 ° C. for 2 hours, 280 parts of B resol solution and 1.2 parts of a mixed esterification catalyst of sulfuric acid / hypophosphorous acid = 3/7 are thoroughly mixed and added dropwise over 1 hour. During this period, toluene and water (reaction dehydration by esterification) were collected through a condenser with a water separator to keep the temperature at 260 ° C. Then 6
It was pumped out when the acid value reached 20 after reacting with time.

This rosin-modified phenolic resin had an acid value of 20, a weight average molecular weight of 23.200 (by GPC method), and a melting point of 158 ° C (capillary method).

Example 2 In the same reaction apparatus as in Example 1, 120 parts of B resol solution was reacted with 200 parts of rosin without catalyst, and B novolak solution was acidified to 24 in the same process as in Example 1 under acidic catalyst. Reacted.

The acid value of this resin is 24, the weight average molecular weight is 18700, and the melting point is 152 ° C.
Met.

Example 3 200 parts of Chinese gum rosin was charged into the same apparatus as in Example 1, heated while blowing nitrogen gas, melted and stirred at 200 ° C. or lower, and 240 ° C., 120 parts of A resol solution was added dropwise over 1 hour. After reacting for 2 hours, 200 parts of A resol solution and p-
Toluene sulfonic acid / hypophosphorous acid = 1/1 catalyst solution 1.2 parts was mixed well and added dropwise to the reaction system at 240 ° C over 1 hour.
After stirring for 30 minutes, an acid value of 23 was pumped out.

This resin had an acid value of 23, a weight average molecular weight of 22,800 and a melting point of 163 ° C.

Example 4 In the same process as in Example 3, 200 parts of Chinese gum rosin and 120 parts of A resole solution were reacted without a catalyst, and then A novolac solution 200 was added.
And 2.5 parts of an esterification catalyst of p-toluenesulfonic acid / hypophosphorous acid = 1/1 were mixed well, added dropwise and subjected to an esterification reaction for 8 hours, and an acid value of 26 was pumped out.

This resin had an acid value of 26, a weight average molecular weight of 19,700 and a melting point of 159 ° C.

Comparative Example 1 (Preparation of varnish from conventional resin and naphthenic solvent) 200 parts of Chinese gum rosin were charged into the same reactor as in Production Example 1 and heated while blowing nitrogen gas, and stirring was started at 200 ° C and further 230 ° C. The temperature was raised to 150 ° C and 150 parts of Hitachinol 2501 (p-octylphenol resol-type phenol resin manufactured by Hitachi Chemical) was added over 2 hours, and the reaction was conducted for 2 hours at the same temperature, the acid value was 83, and esterification occurred. Not not. After this, 16 parts of glycerin was added and the reaction was carried out for 8 hours, the acid value decreased to 16. This resin had a melting point of 143 ° C. and a weight average molecular weight of 17,400.

Comparative Example 2 200 parts of Chinese gum rosin were charged in the same reactor as in Example 1, heated while blowing nitrogen gas, stirred at 200 ° C. and heated up to 260 ° C., 400 parts of B resole solution was added to p-toluene sulfone. Acid / hypophosphorous acid = 1/1 catalyst solution (2.5 parts) was mixed well, added dropwise over 2 hours, stirred for 4 hours, and pumped out with an acid value of 18. The acid value of this resin is 18, the weight average molecular weight is 5700,
The melting point was 150 ° C.

[Ink conversion evaluation]

a. Preparation of varnish Varnishing (A) Examples of 6 kinds of rosin-modified phenolic resins obtained
1. Varnishing of the resins of Example 2 and Comparative Example 2 was performed using resin 200
, No. 00 polymerized oil 40 parts, Nisseki No. 0 solvent H (Nippon Petrochemical normal paraffin) 160 parts were charged into a four-necked flask and kept warm for 30 minutes while blowing nitrogen gas, then 10
After cooling to 0 ° C., 3 parts of ALCH (gelling agent manufactured by Kawaken Fine Chemicals Co., Ltd.) was added, the temperature was raised to 180 ° C., and the mixture was stirred for 1 hour to obtain a gel varnish (A).

Varnishing (B) Varnishing of the resins of Examples 3, 4 and Comparative Example 1 was carried out by adding 200 parts of resin, 60 parts of polymerized oil No. 00 and 140 parts of Nisseki No. 5 solvent (ink solvent made by Nippon Petrochemical Co., Ltd.). Charge into a one-necked flask,
The temperature was raised to 180 ° C., the mixture was stirred at 30 ° C., cooled to 100 ° C., 3 parts of AlCH 3 was added, the temperature was raised to 180 ° C., and the reaction was carried out for 1 hour to give a gel varnish (B).

b. Preparation of Ink An ink (A) was prepared using each of the inks obtained from the ink-formation (A) -gel varnish (A). That is, gel varnish (A)
Carmin 6BA (red pigment manufactured by Toyo Ink Mfg. Co., Ltd.) 1 in 60 parts
8 parts were dispersed using a 3-roll mill, and a total amount of 10 parts was obtained using Nisseki No. 0 Solvent H and varnish and / or gel varnish.
0 copies, tack value 5.5-6.0, flow value 19.0
It was adjusted to be ~ 20.0 (at 25 ° C).

However, the ink of Comparative Example 2 had a flow value of 23.2 even if the tack value was 6.0, making it impossible to adjust the viscosity of the ink.

Inkification (B) -Using each of the gel varnishes (B) obtained, the Nisseki No. 0 solvent H used in the Inksification A was replaced with the Nisseki No. 5 solvent, and the manganese dryer 2 was used. Parts, drying inhibitor 0.3 parts, wax compound 3 parts, tack value 6.5-7.0, flow value 1
Adjusted to 7.5-18.5.

[Print test]

Ink is evaluated for Ink A by Mitsubishi Heavy Industries L-500
A printing test was performed using an off-wheel printer and a TEC dryer made by Inoue Metal. The evaluation results are shown in Table-1.
The evaluation method is as follows.

Drying temperature-The printed material immediately after being ejected was free from stickiness, and the paper surface temperature at the dryer outlet at that time was judged.

Gloss-Made by Murakami Gloss Meter GM26D (60 ° -60 °)
Was measured using.

Water Width-Indicated by the water bar dial of the press to obtain a normal print. In other words, if you set the dial of the water rod to a value larger than the upper limit, a water spot will appear on the image area. On the other hand, if it is set to a value smaller than the lower limit value, soiling will occur.

Further, the evaluation of the ink B was performed by a Mitsubishi DAIYA-1 sheet-fed printing machine manufactured by Mitsubishi Heavy Industries. The results are shown in Table-2.

As described above, the resin of the present invention is an excellent printing ink resin.

Claims (4)

[Claims] 1. A reaction component obtained by reacting a resol-type phenol resin and rosin in the absence of a catalyst, and a reaction component obtained by reacting a resol-type phenol resin and / or a novolac-type phenol resin with a rosin under an acidic catalyst. A resin for printing ink, which is a rosin-modified phenolic resin containing an acid value of 40 or less. 2. The resol type phenolic resin or the novolac type phenolic resin is pt-butylphenol,
The resin for printing ink according to claim 1, which is a condensate of formaldehyde mainly containing at least one selected from p-octylphenol and p-nonylphenol. 3. The printing ink according to claim 1 or 2, wherein the weight ratio of rosin to phenol resin in the rosin-modified phenol resin is 30 to 150 with respect to 100 rosin. resin. 4. 100 parts by weight of rosin and 30 to 150 phenolic resin
A rosin-modified phenolic resin obtained by reacting parts by weight, the first step of reacting the rosin and the resole-type phenolic resin in the absence of a catalyst, and the weight ratio to the resole-type phenolic resin used in the first step is 0.8. A method for producing a resin for printing ink, which comprises a second step of adding the resole-type phenol resin and / or the novolac-type phenol resin and the acid catalyst of 4 to react them until the acid value becomes 40 or less.