JPH0573153B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a resin for printing ink and a method for producing the same. [Prior Art] Hitherto, rosin-modified phenolic resins have been used as resins for printing inks, particularly as resins for offset printing inks. However, in recent years, there has been a strong demand for printing ink resins to be suitable for high-speed printing due to demands for labor-saving and high-speed printing.
In particular, when the solvent is absorbed into the paper fibers and coating layer, the ink rapidly thickens, and the color does not transfer to the back side of the printed matter that is piled up one after another.
In addition to "good setting" (meaning that the elapsed time from printing to setting is short), other performance requirements are also becoming more sophisticated. However, conventional printing ink using a rosin-modified phenolic resin as a vehicle has drawbacks such as insufficient setting and misting (a phenomenon in which the printing ink becomes atomized and scatters when the printing press is operated). In general, gloss, drying performance, and setting are contradictory performances, and it is often difficult to maintain a balance between the two.
There is a need for the development of a resin for printing ink that can simultaneously satisfy the following requirements (printability). [Problems to be Solved by the Invention] In view of the fact that conventionally known rosin-modified phenolic resins cannot satisfy the printability during high-speed printing, the present inventors have developed a new printing ink that can solve the drawbacks. The aim was to develop a resin for [Means for Solving the Problems] In view of the above problems, the present inventors focused on the molecular structure, physical constants, etc. of the rosin-modified phenolic resin and conducted intensive studies on various manufacturing methods to obtain the desired resin. I did this. As a result, the present inventors conducted a so-called novolac reaction between a specific rosin-phenol reactant and formaldehyde in the presence of an acid catalyst, and then subjected this to an esterification reaction to obtain a specific phenol-modified rosin resin for the purpose of the present invention. It has been discovered that this resin can be used as an excellent printing ink resin that meets the following requirements (see specification of Japanese Patent Application No. 1982-1920). Furthermore, in order to provide a resin that further improves the gloss and solubility of the resin for printing ink, the present inventors conducted intensive studies focusing on phenols, which are the raw materials used, and found that Furthermore, we have found that it is effective to use specific alkylphenols in combination. The present invention was completed based on this new knowledge. That is, the present invention is a reaction product obtained by heat-reacting rosins and phenols in the presence of an acid catalyst, alkylphenols having an alkyl group having 4 to 12 carbon atoms, and formaldehyde in the presence of an acid catalyst. A printing ink resin comprising a reaction product obtained by converting the novolak into a novolak and then esterifying the novolak, and a reaction product obtained by subjecting rosins and phenols to a heating reaction in the presence of an acid catalyst. This invention relates to a method for producing a resin for printing ink, which comprises reacting alkylphenols having an alkyl group having 4 to 12 carbon atoms and formaldehyde in the presence of an acid catalyst to form a novolak, which is then subjected to an esterification reaction. [Function and Examples] The present invention relates to a resin for printing ink having a novel molecular structure that is clearly different from that of conventional resins, and a method for producing the same. A printing ink with excellent high-speed printing suitability can be obtained in which the problems encountered with phenolic resins have been largely eliminated. Below, the method for producing a printing ink resin of the present invention and the characteristics of the obtained printing ink resin will be explained. The resin for printing ink of the present invention is produced by forming a novolak from a specific intermediate, a specific alkylphenol, and formaldehyde, and then esterifying the novolak by maintaining the novolak at a high temperature in the presence or absence of a polyhydric alcohol. It can be obtained by forcing people. In the printing ink resin of the present invention, as a first step,
Predetermined amounts of the intermediate, alkylphenols, and formaldehyde are charged, and the mixture is heated in the presence of an acid catalyst to approx.
A novolak compound is obtained by reacting at 100-120°C for 3-6 hours. The intermediate in the present invention is a reaction product obtained by subjecting rosins and phenols to a heating reaction in the presence of an acid catalyst. Here, rosin refers to gum rosin, oil rosin, tall oil rosin, disproportionated rosin, polymerized rosin, and the like. Phenols include carbolic acid,
Cresol is preferred. Preferred acid catalysts include para-toluenesulfonic acid, dodecylbenzenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, sulfuric acid, hydrochloric acid, boron trifluoride, anhydrous aluminum chloride, and the like. This intermediate can be easily produced by employing the following method. That is, for 1 mole of the rosin, 1.5 to 4 moles of phenol are added in the presence of an acid catalyst to about 140 to 140 moles of phenol.
React at 180°C for 4-14 hours. Furthermore, unreacted phenols are distilled off while gradually increasing the temperature in the reaction system until the final temperature reaches 250 to 300°C. There are no particular restrictions on the amount of acid catalyst used, but it is usually 0.05 to 0.5% (weight%, same below) based on rosin.
It is said that Although the structure of this intermediate is still unclear, it is thought that the main reaction product is a Friedel-Crafts reaction between phenols and rosins, in which the hydrogen atom at the para position of the phenols is replaced by the rosin. It will be done. The intermediate can be appropriately adjusted by manipulating the reaction conditions so that the intermediate has an acid value of 100 to 110, a hydroxyl value of 60 to 90, and a softening point of 100 to 120°C. Examples of the alkylphenols used in novolacizing the intermediates include various alkylphenols in which the alkyl group has 4 to 12 carbon atoms, preferably 4 to 9 carbon atoms. Specific examples include butylphenol, amylphenol, octylphenol, nonylphenol, dodecylphenol, and the like. There is no particular limit to the amount of the alkylphenol used, and it is determined by taking into consideration the gloss and solubility of the resulting printing ink resin, but it is usually determined based on 100 parts (parts by weight, hereinafter referred to as action) of the intermediate. The amount may range from 10 to 100 parts, preferably from 15 to 65 parts. If it exceeds 100 parts, the softening point of the resin for printing ink will be significantly lowered, which is not preferable. Formaldehyde is an essential component for converting the intermediate into a novolak-type phenol-modified rosin resin. Formaldehyde herein means a formaldehyde supply substance, and examples thereof include formaldehyde and paraformaldehyde. The amount of formaldehyde used varies depending on the type of alkylphenol and the amount used, but is usually 4 to 22% based on the intermediate. If the amount of formaldehyde used is less than 4%, the molecular weight of the resulting resin will decrease, and 22%
If it exceeds this, the molecular weight will be high and in some cases gelation will occur, which is not preferable. There are no particular restrictions on the type of acid catalyst used to obtain the novolac body, and various known novolac catalysts used in the production of ordinary novolac resins can be used. Specifically, the various materials used in producing the intermediates can be used as they are. The amount of the acid catalyst used is usually 0.01 to 0.5% based on the intermediate. There are no particular limitations on the acid value and molecular weight of the novolak compound thus obtained, but it is usually preferred that they be 80-100 and 700-1200, respectively. Next, as a second step for converting the novolak body into the printing ink resin of the present invention, the novolak body is subjected to an esterification step. Here, the esterification step refers to the esterification process that occurs between the carboxyl group derived from rosin and the phenolic hydroxyl group derived from phenol present in the novolac body, if a polyhydric alcohol is not used for the novolac body. On the other hand, when a polyhydric alcohol is used for a novolac compound, not only the dehydration reaction but also the reaction between the carboxyl group derived from the rosin and the alcoholic hydroxyl group derived from the polyhydric alcohol occurs. Refers to a dehydration reaction. The esterification reaction is carried out as follows. That is, the esterification reaction is carried out, for example, by esterifying the novolak compound and a polyhydric alcohol in the presence of an acid catalyst at about 200 to 27°C with stirring for 5 to 15 hours until the desired acid value and softening point are reached. This is done by As mentioned above, the polyhydric alcohol is used as an optional component in the esterification step of the present invention, and the type thereof is not particularly limited in the present invention, and various known ones may be used. I can do it. Specific examples of such polyhydric alcohols include glycerin, trimethylolethane, trimethylolpropane, diethylene glycol, and pentaerythritol. Since the amount of polyhydric alcohol used is closely related to the solubility of the resulting printing ink resin,
It is limited to some extent, and is usually limited to a maximum of 10%, preferably 6%, based on the novolak. If it exceeds 10%, it is not preferable because the solubility decreases. Incidentally, triphenyl phosphite or triphenyl phosphate can also be used as a co-catalyst for esterification, if necessary. The reaction product thus obtained usually has an acid value of 50 or less, preferably 40 or less. Acid value
This is because if it exceeds 50, problems such as stains tend to occur during printing. Further, the softening point of the resin is usually 160°C or higher, preferably 170°C or higher. This is because if the temperature is lower than 160°C, the drying property and setting will be significantly reduced. The solubility of the resin for printing ink of the present invention, which is the reaction product obtained in this way, is appropriately determined in consideration of the workability during printing ink production and printing, and is usually determined by Preferably, the tolerance is 8 g/g or more. Here, the tolerance refers to the amount (g) of solvent used until the dissolved material becomes cloudy when 1 g of resin is dissolved with the solvent. Furthermore, the resin for printing ink clearly contains methylene bonds based on the novolacification reaction and ester bonds based on the esterification reaction. This fact is confirmed by NMR and IR measurement results. For example, according to IR, a characteristic absorption of the ester bond is observed at 1748 cm ^-1 . The resin for printing ink of the present invention can be made into a printing ink by suitably blending and kneading various known pigments, petroleum solvents, drying oils, additives, etc. according to a conventional method. The printing ink is particularly useful for offset printing, and can also be suitably used for letterpress printing and gravure printing. Incidentally, when preparing the ink, it is of course possible to use an appropriate amount of a known resin for printing ink such as a rosin-modified phenolic resin. Hereinafter, the present invention will be explained in more detail with reference to Reference Examples and Examples, but the present invention is not limited to these Examples. Reference Example 1 A flask equipped with a stirrer, a Liebig condenser, and a thermometer was charged with 1000 parts of gum rosin, 1000 parts of carbolic acid, and 0.7 parts of paratoluenesulfonic acid as an acid catalyst, and the temperature was raised to 150 to 170°C. Next, the reaction was carried out at the same temperature for 5 hours, and the temperature was further raised to 250-260°C while distilling off unreacted carbolic acid.
The phenol reactant (hereinafter referred to as intermediate) is approximately
1250 copies sold. The acid value of the intermediate is 107 and the softening point is 110.
℃, and the hydroxyl value was 75. Reference Example 2 In Reference Example 1, the amount of carbolic acid used was reduced to 570 parts, and the reaction time at 150 to 170°C was changed to 10 to 13 parts.
The same operation as in Reference Example 1 was carried out except that the time was extended, and about 1200 parts of an intermediate having an acid value of 105, a softening point of 120° C., and a hydroxyl value of 70 was obtained. Example 1 1000 g of the intermediate obtained in Reference Example 1 was placed in a flask equipped with a stirrer, a Liebig condenser, and a thermometer.
1 part, 200 parts of paraoctylphenol, 63 parts of paraformaldehyde, 0.5 part of paratoluenesulfonic acid, and 212 parts of xylene were charged, and the temperature was raised to 100 to 110°C. After carrying out the novolacification reaction at the same temperature for 4 hours, the
The temperature was raised to . Furthermore, an esterification reaction was carried out at the same temperature for 10 hours, and the resin for printing ink of the present invention was
1137 copies were sold. The acid value of this substance is 23, and the softening point is
The temperature was 177°C, and the tolerance of the resin to a petroleum solvent (manufactured by Nippon Oil Co., Ltd., trade name "Nisseki No. 5 Solvent") was 20 g/g or more at 25°C. Example 2 In Example 1, paraoctylphenol,
The same operation as in Example 1 was carried out except that the amounts of paraformaldehyde and xylene used were changed to 400 parts, 95 parts, and 247 parts, respectively, to obtain 1346 parts of a resin having an acid value of 25 and a softening point of 176°C. The resin Nisseki 5
Tolerance for No. Solvent is 20g/at 25℃
It was more than g. Example 3 In Example 1, paraoctylphenol,
The amounts of paraformaldehyde, paratoluenesulfonic acid and xylene used were 600 parts each,
The same operation as in Example 1 was carried out except that the amounts were changed to 127.3 parts, 0.68 parts, and 282 parts, and the acid value was 22 and the softening point was 181.
1554 parts of resin was obtained at ℃. The tolerance of this resin to Nisseki No. 5 solvent was 20 g/g or more at 25°C. Example 4 In Example 1, paraoctylphenol,
The amounts of paraformaldehyde, paratoluenesulfonic acid and xylene used were 900 parts each,
The same operation as in Example 1 was performed except that the amounts were changed to 157.5 parts, 0.75 parts, and 336 parts, and the acid value was 30 and the softening point was 169.
1852 parts of resin was obtained at ℃. The tolerance of the resin to a petroleum solvent (manufactured by Nippon Oil Co., Ltd., trade name "Nisseki No. 5 Solvent") was 20 g/g or more at 25°C. Example 5 The same operation as in Example 3 was carried out except that paraoctylphenol was changed to paratertiary butylphenol and the amount of paraformaldehyde used was changed to 154.6 parts.
19. 1558 parts of resin with a softening point of 183°C was obtained. The tolerance of this resin to Nisseki No. 5 solvent is 25℃.
It was 8.3g/g. Example 6 The same procedure as in Example 3 was carried out except that paraoctylphenol was replaced with paranonylphenol and the amount of paraformaldehyde used was changed to 127.0 parts. Acid value 21, softening point 163
1563 parts of resin was obtained at ℃. The tolerance of this resin to Nisseki No. 5 solvent was 20 g/g or more at 25°C. Example 7 The same procedure as in Example 1 was carried out up to the novolacification reaction, and after heating to 250 to 260°C, 50 parts of glycerin was added and the esterification reaction was carried out at the same temperature for 8 hours, resulting in an acid value of 21 and softening. 1182 parts of resin with a temperature of 176°C were obtained. The tolerance of this resin to Nisseki No. 5 solvent was 20 g/g or more at 25°C. Example 8 In Example 1, the same operation as in Example 1 was carried out except that the type of intermediate used was changed to that obtained in Reference Example 2, and a resin with an acid value of 20 and a softening point of 179°C was obtained.
1132 copies were sold. The tolerance of this resin to Nisseki No. 5 solvent was 20 g/g or more at 25°C. Comparative Example 1 Commercially available rosin-modified phenolic resin (manufactured by Arakawa Chemical Industry Co., Ltd., trade name "Tamanol 354", acid value 18, softening point
The tolerance for Nisseki No. 5 solvent was 4.0 g/g at 25° C. at 170° C. Comparative Example 2 Using the same reaction apparatus as Example 1, Reference Example 1
1000 parts of the resulting intermediate, paraformaldehyde
45 parts, 1.5 parts of para-toluenesulfonic acid, and 150 parts of xylene were charged, and the temperature was raised to 100 to 110°C.
After carrying out the novolacization reaction at the same temperature for 4 hours, the temperature was heated to 250-260°C while distilling off xylene. Further, an esterification reaction was carried out at the same temperature for 8 hours, yielding approximately 950 parts of resin for printing ink.
The acid value of this product was 25, the softening point was 177°C, and the tolerance of this resin to Nisseki No. 5 solvent was 5.7 g/g at 25°C. Inks were prepared by the following method using the printing ink resins of the present invention obtained in Examples 1 to 8 and the comparative printing ink resins obtained in Comparative Examples 1 and 2, and their ink performance was evaluated. was evaluated. The evaluation results are shown in Table 1. (Preparation of ink) A varnish was obtained by mixing and dissolving 45 parts of resin, 25 parts of linseed oil, and 30 parts of Nisseki No. 5 solvent. This varnish was kneaded using three rolls at the following blending ratio to form an ink. Carmine 6B (red pigment) 20 parts The above varnish 65-70 parts Nisseki No. 5 solvent 4-9 parts Friction improver (wax-based compound) 5 parts Ink dryer 1 part Based on the above formulation, the tack value of the ink is 9 ±
0.5, and the flow value was adjusted to be 18±0.5. (Gloss) After applying 0.4 ml of ink on art paper using an RI tester (manufactured by Mei Seisakusho Co., Ltd.), the humidity was controlled at 20°C and 65% RH for 24 hours, and the reflectance at 60°-60° ( %) was measured using a gloss meter. (Set) After spreading 0.4ml of ink onto art paper using an RI tester (manufactured by Mei Seisakusho Co., Ltd.), divide the displayed color into pieces by time, and use the RI tester roller to divide the displayed color into different pieces of art. Observe the degree of ink adhesion on the paper,
The time (minutes) until the ink stopped adhering was measured. (Misting) Charge 4ml of ink to the inkometer,
The paper was rotated at 400 rpm for 1 minute and then at 1200 rpm for 3 minutes, placed directly below the roll, and the degree of ink scattering on the white paper was observed and evaluated according to the following criteria. ◎: Misting did not occur. ○: Misting occurred slightly. Δ: Misting occurred to a noticeable extent. ×: Misting was completely generated.

[Table] [Effects of the Invention] The printing ink resin of the present invention and its manufacturing method have significantly improved the drawbacks of conventionally known rosin-modified phenolic resins, and have improved gloss, setting, misting, etc. even under high-speed printing. Since the printing ink can sufficiently satisfy the printing suitability of the ink, it is possible to provide a printing ink that meets today's demands such as resource saving and high-speed printing.

Claims (1)

[Claims] 1. A reactant obtained by heating rosins and phenols in the presence of an acid catalyst, having 4 carbon atoms.
A resin for printing ink comprising a reaction product obtained by reacting alkylphenols having ~12 alkyl groups and formaldehyde in the presence of an acid catalyst to form a novolak, and then subjecting the novolak to an esterification reaction. 2. The reaction product is directed against the novolak body.
The resin for printing ink according to claim 1, wherein the novolak is subjected to an esterification reaction using a polyhydric alcohol in a range not exceeding 10% by weight. 3 Reactant obtained by heating rosins and phenols in the presence of an acid catalyst, carbon number 4
A method for producing a resin for printing ink, which comprises reacting alkylphenols having ~12 alkyl groups and formaldehyde in the presence of an acid catalyst to form a novolak, and then subjecting this to an esterification reaction.