JP3311095B2 - Printing plate dampening solution - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel fountain solution for printing plates,
More specifically, the harmful microorganisms bacteria, mold,
The present invention relates to a fountain solution for printing plates, which has an excellent antibacterial action over a wide range irrespective of its type against yeasts and the like, prevents the generation of slime, and can circulate for a long period of time.

[0002]

2. Description of the Related Art In lithographic printing, generally, a lipophilic image portion and a hydrophilic non-image portion are provided on the same plane of a plate. 2. Description of the Related Art A method of printing by attaching ink is used. This dampening solution is used, for example, to prevent the printing ink from depositing on the non-image area, to wash the non-image area (to make it insensitive), to wash the image area (a synergistic effect with the water bar roller), and to print the image area. This is used for the purpose of preventing the deterioration of the image (preventing the fluctuation of the image line width) and maintaining the printing temperature constant. Among these, cleaning (desensitization) of the non-image area is particularly important, and the amount of dampening water can be reduced by improving the cleaning (desensitization) effect.

A fountain solution used for such a purpose is usually an acidic aqueous solution having a pH of from 2 to 3, and usually contains
Surface cleaners such as sulfuric acid, phosphoric acid, and citric acid, nonionic surfactants, desensitizing agents, buffers such as sodium phosphate, ammonium monophosphate, sodium citrate, ethyl alcohol, and inpropyl Contains water retention and drying regulators such as alcohol.

Among these components, desensitizing agents incorporated for washing non-image areas include gum arabic, carboxymethylcellulose, sodium alginate, ammonium alginate, starch oxide, sodium hexametaphosphate, sodium phosphate, There are many nutrients of bacteria such as sodium citrate and sodium tartrate, and when circulating the dampening water, bacteria and fungi taken from the atmosphere and from the makeup water will proliferate and important In addition to causing a reduction in the desensitizing effect and a bad smell from the dampening solution, it forms slime and blocks various pipes and storage tanks of the dampening solution circulation system.

[0005] Since isopropyl alcohol used as a water retention and drying regulator has a bacteriostatic effect, the above-mentioned troubles can be suppressed to some extent by adding it as a component. As regulations have been tightened and the use of isopropyl alcohol has been restricted, it is no longer possible to expect the antibacterial action of this use.

Therefore, in general, a compound having a fungicidal action is added to the dampening solution as a component to suppress the growth of bacteria and fungi. Fungicides and fungicides for preventing the occurrence of bacteria and mold include dichloroisocyanurate, 2,4,6-trichlorophenol, methylenebisthiocyanate, 2-mercaptobenzothiazole, 3,5-dimethyltetrahydro-
1,3,5-2H-thiadiazine-2-thione, 2-
Compounds such as (2-furyl) -3- (5-nitro-2-furyl) acrylamide, N-bromoacetamide, and 1,4-bisbromoacetoxy-2-butene are known. Low effect on mold generated in water, lack of sustained effect, inhibit rust prevention, reduce ink adhesion of printing plate, promote emulsification of ink, limit usage conditions However, it is not always satisfactory to mix it in a fountain solution for printing plates due to reasons such as the presence of a fountain solution.

Recently, a 4-isothiazolin-3-one compound has been proposed as a compound to be added to the processing solution for printing plates (Japanese Patent Publication No. 1-26051), and a considerable effect has been recognized. Since the compound has a narrow antibacterial spectrum and limits the types of microorganisms that can be suppressed, it is unavoidable that bacteria and mold will be generated when the fountain solution is reused over a long period of time, Depending on the composition, there is a drawback that the desensitizing effect and the performance of the ink are reduced.

[0008] The fountain solution usually contains different components depending on the maker, but can meet the demand that the fountain solution does not inhibit the effect of the fountain solution and is effective against a wide range of bacteria and fungi. Is not known.

[0009]

Under such circumstances, the present invention provides (1) excellent harmful microorganisms such as bacteria, molds, yeasts, etc. in a wide range regardless of their types. Has antibacterial action, (2) can prevent slime formation, (3) does not interfere with performance required for dampening solution such as desensitization, (4) has low skin irritation and is easy to handle It is a fountain solution having excellent properties such as certain ones, and has been made for the purpose of providing a fountain solution for printing plates that can prevent troubles caused by harmful microorganisms even when used for a long period of time.

[0010]

DISCLOSURE OF THE INVENTION The present inventors have developed a fountain solution for a printing plate which has an effective antibacterial effect against a wide range of bacteria and mold without inhibiting the fountain solution effect. As a result of various studies to develop the compound, 1,2-bisbromoacetoxyethane, a specific aliphatic nitro alcohol and optionally 3,3,4,4-tetrachlorotetrahydrothiophene-1,1-dioxide were obtained. The fountain solution for printing plates containing the combination was found to exhibit an antibacterial spectrum in a wide range without impairing the original performance of the fountain solution, and based on this finding, the present invention was accomplished.

That is, the present invention relates to (A) 1,2-bisbromoacetoxyethane, (B) a compound represented by the general formula

Embedded image Wherein R ¹ and R ² are each a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl group, and X is a halogen atom, and optionally (C) 3,3,4 The present invention provides a fountain solution for a printing plate, characterized in that it contains 1,4-tetrachlorotetrahydrothiophene-1,1-dioxide.

The 1,2-bisbromoacetoxyethane used as the component (A) in the fountain solution of the present invention is a compound known as an industrial bactericide (JP-A-53-34).
No. 920), when it is added alone to a fountain solution, the effect of inhibiting the growth of Gram-negative bacterium Entropobacter and gram-positive bacterium Staphylococcus bacteria present in the atmosphere is small, and thus satisfactory results are obtained. Can not be obtained.

The aliphatic nitro alcohol of the above formula (I) used as the component (B) includes R ^{1 in} the formula
And R ² are a hydrogen atom, a linear or branched alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a ter
Those such as a t-butyl group are preferred. This alkyl group may be substituted with a substituent such as a halogen atom, a hydroxyl group, an alkoxy group, an amino group, an acyl group or the like, particularly a hydroxyl group. These R ¹ and R ² may be the same or different. X in the formula represents a halogen atom such as a chlorine atom, a bromine atom and an iodine atom, and a bromine atom is particularly preferred.

Examples of the aliphatic nitro alcohol represented by the general formula (I) include 2,2-dibromo-2-nitroethanol, 2-bromo-2-nitro-1,3-propanediol, 1,1 -Dibromo-1,1-nitro-2
-Propanol, 3-bromo-3-nitropentane-
2,4-diol and the like can be mentioned.

These aliphatic nitro alcohols are compounds known as industrial germicides (Japanese Patent Publication No. 40-89).
No. 17), when this is added alone to a fountain solution,
Gram-negative bacteria have a small antibacterial effect against Pseudomonas aeruginosa and molds, and satisfactory results cannot be obtained.

As described above, the fountain solution containing the component (A) or the component (B) alone has a limited fungicidal effect only to specific microorganisms, and does not always provide satisfactory results. Although the sustainability of the antibacterial effect is also insufficient, if both are used together, harmful mold, bacteria,
Yeasts can be protected against a wide range of bacteria.

The content ratio of component (A) to component (B) in the fountain solution of the present invention is in the range of 10: 1 to 1: 5, preferably 5: 1 to 1: 2 by weight. It is desirable. If this content ratio deviates from the above range, a broad antibacterial spectrum cannot be obtained.

In the fountain solution of the present invention, in addition to the above components (A) and (B), if desired, 3,3,4,4-tetrachlorotetrahydrothiophene-1,3 1-dioxide can be used. The 3,3,4,4-tetrachlorotetrahydrothiophene-1,1-dioxide is a compound known as an industrial bactericide (US Pat. No. 2,957,887). Even if it is mixed with water, the bactericidal effect is insufficient and lacks sustainability, and the above-mentioned components (A) and (B)
When used in a fountain solution in combination with a component, a sufficient antibacterial effect and its durability can be exhibited for the first time.

When the component (C) is blended, its content is selected so as to fall within the range of 1 to 50 parts by weight per 100 parts by weight of the total amount of the components (A) and (B). Is preferred. If the amount is smaller than this, the effect of blending the component (C) becomes insufficient, and if the amount is larger than this, no remarkable difference is produced particularly in the effect.

In the present invention, (A) is added to the fountain solution.
The component, the component (B), and the component (C) optionally used are prepared in advance in the form of a master solution containing each component at a high concentration, and if necessary, added to a dampening water to obtain a predetermined solution. It is advantageous to adjust the concentration to.

The final content of the component (A), the component (B) and the optional component (C) in the fountain solution of the present invention thus adjusted is 0.01 to 0.5 g / g. Liter, preferably in the range of 0.02 to 0.2 g / liter. If the amount is less than 0.01 g / l, a sufficient antibacterial effect cannot be obtained, and if it is more than 0.5 g / l, the performance as a fountain solution decreases.

The fountain solution for a printing plate of the present invention may contain various components conventionally used in fountain solutions, in addition to the combination of the components (A), (B) and optionally the component (C). ,
For example, surface detergents such as sulfuric acid, phosphoric acid, and citric acid, surfactants such as nonionic surfactants, gum arabic, carboxymethylcellulose, sodium alginate, ammonium alginate (high-viscosity products, low-viscosity products), oxidized starch, It may contain desensitizing agents such as sodium hexametaphosphate and sodium tartrate, buffers such as sodium phosphate, ammonium monophosphate and sodium citrate, and water retention / drying agents such as ethyl alcohol and isopropyl alcohol. .

[0023]

The fountain solution for a printing plate of the present invention has excellent antibacterial action in a wide range against harmful microorganisms such as bacteria, molds and yeasts irrespective of their types. (2) Since the adhesive substance is changed to a non-adhesive substance, the generation of slime can be prevented. (3) The performance required for dampening solution such as desensitization is not impaired. (4) Skin irritation In addition to showing excellent properties such as weakness and easy handling, even if used for a long period of time, it will not cause troubles due to harmful microorganisms (such as generation of bad smell, slime, desensitization effect etc.) There are advantages.

[0024]

Next, the present invention will be described in more detail by way of examples.

The indicator microorganisms in each case include Bacillus subtilis (Bacillus subtilis).
tilis), Entrobacter aerogines (En)
troobacter aerogenes), Pseudomonas a
eruginosa), Trichoderma sp. (T
richoderum sp. ), Aspergillus
Niger (Aspergillus niger), Geotrichum sp.
p. ), Cephalosporium spices (Cepha)
losprium sp. ) Was used.

Example 1 5 parts by weight of 1,2-bisbromoacetoxyethane and 2,2
-Dibromo-2-nitroethanol (8 parts by weight) was dissolved in a glycol solvent to make the total amount 100 parts by weight, thereby preparing a master solution. Next, the above master solution was added in different amounts to a stock solution of a fountain solution having no antibacterial action to form five types of mixtures, and the mixture was diluted 100-fold with sterile water to obtain a concentration of 0.005 wt. %, 0.01%, 0.05%, 0.1% and 0.5% by weight of the sample were prepared.

Each 100 ml of this sample was dispensed into an Erlenmeyer flask, and 1 ml of the pre-cultured indicator microorganism was added to each, and a continuous shaker (60 times / shaking) was placed in a constant temperature room at 30 ° C. for 4 days. ), 1 ml each was taken in a petri dish, and cultured on a dissolved denatured Waxman agar medium in a thermostat maintained at 30 ° C. for 4 days to observe the presence or absence of colonies.

Separately, the above sample was applied to the surface of an aluminum plate, and one drop of a commercially available printing ink was applied in a wet state.
After the dropping, the cloth was lightly wiped with a cloth, and it was visually determined whether or not the ink remained on the surface. Table 1 shows the results.

[0029]

[Table 1]

As is clear from this table, if the concentration of the master liquid is less than 0.01% by weight, a sufficient antibacterial effect cannot be obtained. Certain desensitizing performance is reduced.

Example 2 10% by weight of 1,2-bisbromoacetoxyethane and 3,3
3,4,4-tetrachlorotetrahydrothiophenone-
A master solution was prepared by dissolving 2 parts by weight of 1,1-dioxide and 10 parts by weight of 2-bromo-2-nitro-1,3-propanediol in a glycol solvent to make the total amount 100 parts by weight. Example 1 using this master solution
Table 2 shows the results of the test performed in the same manner as in the above.

[0032]

[Table 2]

Example 3 Instead of 8 parts by weight of 2,2-dibromo-2-nitroethanol in Example 1, 2-bromo-2-nitro-1,3 was used.
-A master solution was prepared in the same manner as in Example 1 except that 8 parts by weight of propanediol was used. Using this master solution, the results of a test performed in the same manner as in Example 1 are shown in Table 3.

[0034]

[Table 3]

Example 4 8% by weight of 1,2-bisbromoacetoxyethane and 2,2
A master solution was prepared by dissolving 5 parts by weight of -dibromo-2-nitroethanol in a glycol solvent to make the total amount 100 parts by weight. Table 4 shows the results of a test performed using this master solution in the same manner as in Example 1.

[0036]

[Table 4]

Comparative Example 1 A master solution was prepared by dissolving 13 parts by weight of 1,2-bisbromoacetoxyethane in a glycol solvent to make the total amount 100 parts by weight. Table 5 shows the results of a test performed using this master solution in the same manner as in Example 1.

[0038]

[Table 5]

Comparative Example 2 2-Bromo-2-nitro-1,3-propanediol 1
A master solution was prepared by dissolving 3 parts by weight in a glycol solvent to make the total amount 100 parts by weight. Table 6 shows the results of a test performed in the same manner as in Example 1 using this master solution.
Shown in

[0040]

[Table 6]

Comparative Example 3 A master solution was prepared by dissolving 13 parts by weight of 2,2-dibromo-2-nitroethanol in a glycol solvent to make the total amount 100 parts by weight. Table 7 shows the results of a test performed using this master solution in the same manner as in Example 1.

[0042]

[Table 7]

Comparative Example 4 A master solution was prepared by dissolving 2 parts by weight of 3,3,4,4-tetrachlorotetrahydrothiophene-1,1-dioxide in a glycol solvent to make the total amount 100 parts by weight. Table 8 shows the results of a test performed using this master solution in the same manner as in Example 1.

[0044]

[Table 8]

Further, the master liquids of Example 1 and Comparative Example 3 were applied to a commercially available fountain solution having no antibacterial effect at a site using a sheet-fed lithographic printing press of yellow, red, indigo and black, respectively. In addition to the undiluted solution, a solution prepared by diluting with tap water 100-fold the concentration of the adjusted solution was 0.05% by weight. Example 3
In about one month, odors and molds were generated from the dampening solution, and slime was formed in pipes and storage tanks of the dampening solution circulating device, and the desensitizing effect was reduced. Further, in Example 1, the fountain solution was circulated for 3 months and used. However, the phenomenon described above was not at all, the ink receptivity was good, and 4000 sheets /
Good prints were obtained over time.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-278364 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41N 3/08 101

Claims (7)

(57) [Claims] (A) 1,2-bisbromoacetoxyethane and (B) a general formula: Wherein R ¹ and R ² in the formula are each a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl group, and X is a halogen atom. Fountain solution. (A) 1,2-bisbromoacetoxyethane, (B) a general formula: Wherein each of R ¹ and R ² is a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl group, and X is a halogen atom, and (C) 3,3,4,4 -A fountain solution for printing plates, characterized by containing -tetrachlorotetrahydrothiophene-1,1-dioxide. 3. The fountain solution for a printing plate according to claim 1, wherein the aliphatic nitro alcohol as the component (B) is 2,2-dibromo-2-nitroethanol. 4. The dampening solution for a printing plate according to claim 1, wherein the content ratio of the component (A) to the component (B) is in the range of 10: 1 to 1: 5 by weight. 5. The printing plate wet according to claim 2, wherein the content of the component (C) is in the range of 1 to 50 parts by weight per 100 parts by weight of the total of the components (A) and (B). Water. 6. The dampening solution for a printing plate according to claim 1, wherein the component (A) and the component (B) are in the range of 0.01 to 0.5 g / liter of the total amount of the dampening solution. 7. The printing according to claim 2, wherein the components (A), (B) and (C) are in the range of 0.01 to 0.5 g / liter of the total amount of the dampening solution. Fountain solution for plates.