JPS625470B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an oil-modified rosin phenolic resin composition that has excellent performance as a vehicle for offset printing inks and has good storage stability. Traditionally, rosin phenolic resins have been most commonly used as vehicles for offset printing inks, but with the development of the printing industry, printing speeds have become increasingly high, and gloss and drying properties (commonly referred to as set) have been increasing. The requirements for ink performance are also becoming more sophisticated. Therefore, various types of resins have been developed to meet these demands. For example, the use of various petroleum resin-modified rosin phenol resins to improve solubility in aliphatic solvents
-27492; 53-38113) and the use of rosin phenol resins modified with cyclopentadiene (Japanese Patent Application Laid-open No. 125494/1983).Also, α, β- Method using unsaturated polybasic acid (Special Publication No. 11354 of 1983)
Or a method using hardened rosin
No. 40669), but although all of these give satisfactory results for each required characteristic of printing suitability, the balance between gloss and set, which is the most important as a vehicle for printing ink, has been reported. It must be said that this is still insufficient. That is, those with good gloss are slow to set, and conversely, those with fast setting have poor gloss. However, in order to resolve the above-mentioned difficulties in the prior art, the present inventors conducted a detailed study of various factors related to gloss and set, and found that in the ink component solidified after transferring the printing ink to the printing material, They found that the higher the amount of vehicle in relation to the pigment, the better the gloss, and the higher the softening point of the resin, the faster the setting. We have discovered that modified rosin phenol resin is extremely superior. Through further detailed studies, the present inventors found that although oil-modified rosin phenolic resin has the above-mentioned features, the solubility of the resin in solvents decreases over time during storage. Knowing that there are drawbacks, and discovering that such drawbacks can be overcome by adding an appropriate amount of antioxidant without impairing any of its excellent features, we have completed the present invention. . That is, the present invention relates to (a) phenols, (b) formaldehyde supply substances, (c) animal and vegetable oils with an iodine value of 100 or more, (d) rosins, and (e) monohydric and/or polyhydric alcohols (hereinafter, these (hereinafter abbreviated as alcohols) is further subjected to an addition condensation reaction with (f) a monobasic acid and/or a polybasic acid (hereinafter abbreviated as acids), if necessary.
Contains as main components an oil-modified rosin phenol resin 1 with an oil length of ~40%, a softening point of 60°C or more, and an acid value of 30 or less, and an antioxidant 2, and both of these components are combined with the former resin 1. 0.01 to 5 per 100 parts by weight
The present invention provides a resin composition for printing ink containing the latter antioxidant 2 in a proportion of parts by weight. Here, typical examples of the above phenols (a) include phenol; cresol, pt-
Alkylphenols such as butylphenol, p-octylphenol, or p-nonylphenol; or biphenols such as bisphenol A, etc., and typical formaldehyde supplying substances (b) include formalin and paraformaldehyde. . And each of these above phenols (a)
and formaldehyde feed material (b) are initial resol type phenol formaldehyde obtained by addition reaction in the presence of an alkali catalyst, then neutralized with acid, and then washed with water if necessary. It is particularly preferred to use it in the form of a condensate, combined with other oil-modified, rosin phenol resin forming components (c), (d), (e) and (f), if necessary with Ca, Mg Alternatively, the resin 2 may be obtained by adding a known catalyst such as a hydroxide, oxide, or acetate of Zn, or tertiary amines in a range of 100 to 10,000 ppm to carry out an addition condensation reaction. The resol type phenol-formaldehyde initial condensate is 10 to 35 parts by weight, more preferably 20 to 30 parts by weight when the total amount of the forming components is 100 parts by weight in all oil-modified rosin phenol resin forming components. It is appropriate to set it within the range of
When this condensate exceeds 35 parts by weight, the self-condensate of the condensate itself increases, and when used in a printing ink, the viscosity of the ink becomes extremely high, which is undesirable. If it is less than 10 parts by weight, the molecular weight of the resulting resin will be low,
Furthermore, since the reactivity with the oil component (c) described above also decreases, the viscosity of the ink eventually becomes too low, which is not preferable. Next, typical examples of the oil component (c) include tall oil, cottonseed oil, soybean oil, safflower oil, dehydrated castor oil, linseed oil, tung oil, squid oil, and sardine oil. In addition to these fatty acids, it is also possible to use polymerized oils that are generally widely used for making varnishes, such as di- to tetramers or higher polymers of linseed oil. The oil components (c) as mentioned above may be used alone, or two or more types may be mixed together as required. It is appropriate to use the component (c) in an amount of 5 to 40 parts by weight, more preferably in a range of 5 to 30 parts by weight, based on the total oil-modified rosin phenol resin forming components. . If more than 40 parts by weight is used, the amount of unreacted oil components in the resulting resin will increase, making it impossible to obtain the desired balance between gloss and set; If less than part by weight, this oil component (c)
This is not preferable because the effect of denaturation caused by this is extremely reduced. On the other hand, as for the component (c), the iodine value of the oil is 100.
However, if the iodine value is less than 100, the reactivity with the resol-type phenol formaldehyde initial condensate will be poor, and the desired gloss and set will not be achieved. This is not preferable because it becomes impossible to obtain a well-balanced product. Further, the above-mentioned rosins (d) are rosins such as gum rosin, oil rosin, tall oil rosin, or hardened rosin, and the above-mentioned alcohols (e) include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, and butylene glycol. glycol, neopentyl glycol, hexanediol, hexanetriol,
Typical examples include polyhydric alcohols such as glycerin, trimethylolethane, trimethylolpropane, or pentaerythritol; and higher monohydric alcohols such as hexyl alcohol, nonyl alcohol, or octyl alcohol, and acids (f). are monobasic acids such as benzoic acid or pt-butylbenzoic acid; polybasic acids such as succinic acid, adipic acid, (anhydrous) maleic acid, (anhydrous) itaconic acid, (anhydrous) phthalic acid or trimellitic acid. etc. are listed as representative examples. Normally, the acid (f) is not particularly required, but it is particularly useful when designing a resin with a high molecular weight and a high softening point. In addition, the alcohols mentioned above
Among (e), preferred are trihydric or higher alcohols. When using components (d), (e) and (f), it is preferable that the equivalent ratio of total hydroxyl groups to total carboxylic acids in these components is 0.7 to 1.3, more preferably. ranges from 0.9 to 1.2.
When the equivalent ratio exceeds 1.3, the resulting resin becomes hydrophilic as a result of excess hydroxyl groups, and therefore is easily emulsified by dampening water used during printing, making it unusable for practical use; If it is less than that, the acidity becomes excessive and the molecular weight becomes low, which lowers the softening point too much, which is not preferable. In the synthesis of oil-modified rosin phenol resin 1, these components (d), (e), and (f) may be used as they are, or they may be esterified in the form of an ester condensate by a known and commonly used method. You may use it after doing so. The oil-modified rosin phenol resin (1) can be obtained using the above-mentioned various components (a) to (f), for example, by the following method. First, each of the above-mentioned phenols (a) and formaldehyde supply substance (b) are reacted by a known and commonly used method to obtain a resol type phenol formaldehyde initial condensate, and then the initial condensate thus obtained, Oil component (c), rosin (d), alcohol (e) and, if necessary, acid (f) (however, (d), (e) and (f) among these may be in the form of an ester condensate) and are reacted together by heating at a temperature of 200 to 280°C, or preferably at a temperature of 120 to 180°C in the coexistence of an oil component (c), a rosin (d) and, if necessary, an acid (f). After reacting the resol type phenol formaldehyde initial condensate by dropping it over 1 to 5 hours or adding it in portions, adding the alcohol (e),
By carrying out an esterification reaction at 200 to 280°C, Diels-Alder addition and ester condensation are carried out to obtain a rosin phenol resin (1) modified with an oil component. Next, as the antioxidant 2 as the other main component constituting the composition of the present invention, there is no restriction on its type, and any substance having antioxidant ability may be used, such as oil-modified rosin phenol resin. Basically, any of them can be used as long as they are compatible with each other. Among them, the most representative ones are 2,6-
Phenol-based such as di-t-butylphenol or 2,4-dimethyl-6-t-butylphenol; Phosphorus-based such as triphenyl phosphite or tris-nonylphenyl phosphoite;
Sulfur-based such as dilauryl-3,3'thiodipropionate; amine-based such as phenyl-α-naphthylamine or N,N'-di-phenyl-p-phenylenediamine; imidazole-based such as 2-mercaptobenzimidazole; or a sulfur-phenol covalent system such as 4,4'thiobis-(6-t-butyl-3-methylphenol). The amount of the above-mentioned antioxidant 2 added to the oil-modified rosin phenol resin 1 depends on the type of antioxidant 2 used, but is usually 0.01~
It is 5phr. In this case, it is of course possible to use two or more kinds of antioxidants in combination. A blend exceeding the limit of the antioxidant 2 specified herein poses no problem from the viewpoint of storage stability of the composition of the present invention, but it may cause problems in the ink film after printing using the composition of the present invention. During curing, the degree of inhibition of crosslinking due to air oxidation of the oil component is large, making it impossible to form a highly durable ink film, which is undesirable. The resin composition of the present invention thus obtained can be used as a vehicle for printing ink in the same way as the rosin phenol resin commonly used in the past. Since it has already been introduced, it goes without saying that it is not necessary to combine it with the oil component again. That is, the composition of the present invention can be simply dissolved in a solvent and made into an ink, or it can be made into an ink by adding a small amount of polymerized linseed oil. Known and commonly used resins can be added to the composition of the present invention, and it goes without saying that conventional rosin phenol resins that do not contain oil and fat components can also be used as one of them. By using the characteristic composition of the present invention, it is possible to simultaneously satisfy the conventionally contradictory properties of gloss and set, and to provide a printing ink with excellent storage stability. It is. Next, the present invention will be explained in more detail with reference to Examples. Hereinafter, all parts and percentages are based on weight unless otherwise specified. Reference Example 1 (Preparation example of oil-modified rosin phenolic resin) 500 g of rosin and 500 g of linseed oil were charged into a 4-necked kolben equipped with a stirrer, a thermometer, a dropping funnel, and a reflux device, and the temperature was raised to 160°C. . Next, while maintaining the temperature at the same temperature, 250 g of a solid resol-type p-octylphenol formaldehyde initial condensate was added dropwise from the dropping funnel over a period of 2 hours. Hold for 1 hour, then add 50g of glycerin and gradually heat to 250°C over 4 hours.
The temperature was raised to 250 to 260°C for 8 hours, and the esterification reaction was carried out while removing condensed water. The resin thus obtained had an acid value of 20 and a softening point of 126°C. Reference Example 2 (Same as above) 500 g of rosin and 200 g of linseed oil were charged into a 4-neck kolben equipped with a stirrer, thermometer, dropping funnel, and reflux device, and the temperature was raised to 160°C. 300 g of the resol-type p-octylphenol-formaldehyde initial condensate (as a solid) was added dropwise from the dropping funnel over a period of 2 hours, and the temperature was maintained at the same temperature for 1 hour after the addition was completed. Furthermore, add 55g of pentaerythritol to this,
The temperature was raised to 250°C over 4 hours, maintained at 250-260°C, and the esterification reaction was carried out while removing condensed water for 8 hours. The resulting resin had an acid value of 16 and a softening point of 94°C.
It was hot. Reference Example 3 (Preparation example of rosin phenol resin) 500 g of rosin was charged into a four-necked kolben equipped with a stirrer, thermometer, dropping funnel, and reflux device.
The temperature was raised to 160°C, and then the pre-synthesized resol type p-octylphenol was added while maintaining the same temperature.
250 g of formaldehyde initial condensate (as solids) was added dropwise from the dropping funnel over a period of 2 hours, and the same temperature was maintained for 1 hour after the addition was completed. Further, 50 g of glycerin was added thereto, the temperature was raised to 250°C over 4 hours, and the esterification reaction was carried out while maintaining the temperature at 250-260°C for 12 hours while removing condensed water. The resin thus obtained has an acid value of 20 and a softening point of
It was 162℃. Example 1 500 g of the oil-modified rosin phenol resin obtained in Reference Example 1 and 2.5 g of 4,4'-thiobis-(6-t-butyl-3-methyl-phenol) were melt-mixed at 200°C for 5 minutes. The thus obtained composition of the present invention was cooled to room temperature, and then ground to 100 mesh or less to obtain a test sample. Example 2 Oil-modified rosin phenol resin obtained in Reference Example
500 g and 5 g of 2,6-di-t-butyl-4-methyl-phenol were melt-mixed at 150°C for 5 minutes, the thus obtained composition of the present invention was cooled to room temperature, and then ground to 100 mesh or less. and used as a sample. Comparative Example 1 500 g of the oil-modified rosin phenol resin obtained in Reference Example 1 was pulverized as it was into 100 meshes or less to prepare a sample. Comparative Example 2 500 g of the oil-modified rosin phenol resin obtained in Reference Example 2 was pulverized as it was into 100 meshes or less to prepare a sample. Comparative Example 3 500 g of the pure rosin phenol resin obtained in Reference Example 3, which was not subjected to oil modification, was pulverized as it was into 100 meshes or less to prepare a sample. The changes over time when the samples prepared in Examples 1 and 2 and Comparative Examples 1 to 3 were stored at 50°C in air were observed in the following two terms. Change in viscosity when diluted to 50% (Gardner-Holdt scale - 25℃) b) When the sample is diluted to 50% with toluene, n -
Heptane solubility (that is, heptane tolerance - 25°C) In addition, the various samples described above were tested over time for the following items: ink storage stability, gloss, and setting time. The results are summarized in Table 1. The preparation of the varnish and ink, as well as the procedures and evaluation methods for comparative tests of various physical properties of the ink, are as described below.

【table】

[Preparation of varnish]

The formulation of the varnish was based on 45 parts of rosin-modified phenol, 25 parts of polymerized oil, and 30 parts of ink solvent (using Nisseki No. 5 solvent), and the oil-modified rosin phenol resin of each Example and Comparative Examples 1 and 2. If so, reduce the amount of vegetable oil by the amount of oil denaturation, and
On the other hand, in the case of the rosin-modified phenolic resin of Comparative Example 3, cooking was carried out at 250°C for 1 hour, but in the case of the former oil-modified rosin phenolic resin, it only dissolved and was not cooked at this stage.
After that, all the varnishes were dissolved, and after the mixture was cured, 1 part of Al chelate was added and gelatinized at 160° C. for 1 hour to obtain a varnish. [Preparation of ink] Ink was prepared by kneading using three rolls at the following blending ratio. "Carmine 6B" (pigment) 20 parts varnish 65 parts wax 5 parts No. 5 solvent Required amount However, the amount of No. 5 solvent used depends on the tack value.
11-12 and the amount necessary to adjust the flow value to 31-33. [Storage stability of ink] The ink was stored in a closed container at room temperature for one week, and the difference in flow value at the time of preparation and after one week was used as a measure of stability. [Gloss test] After applying 0.4 ml of ink on art paper using an RI tester, the humidity was controlled at 20°C and 65% RH for 24 hours, and the gloss was measured using a 60°-60° gloss meter. [Set test] After applying 0.4 ml of ink on art paper using an RI tester, it was placed on the art paper using an RI tester roller to observe the degree of ink adhesion, and the time until the ink stopped adhering ( minutes) was measured.

Claims (1)

[Claims] 1 (a) phenols, (b) formaldehyde supply material, (c) animal and vegetable oils with an iodine value of 100 or more, (d) rosins, and (e) monohydric and/or polyhydric alcohols,
5 to 40% obtained by further addition-condensation reaction with a monobasic acid and/or polybasic acid, if necessary.
The main component is a mixture of 0.01 to 5 parts by weight of antioxidant 2 to 100 parts by weight of oil-modified rosin phenol resin 1 having an oil length of 60°C or more, a softening point of 60°C or more, and an acid value of 30 or less. A resin composition for printing ink, characterized by: