JPH08302594A - Slime controlling agent for papermaking - Google Patents

Abstract

PURPOSE: To obtain a slime controlling agent for papermaking by dissolving o-phthalaldehyde in propylene carbonate or a solvent consisting essentially of it, excellent in long-term/high-temperature shelf stability. CONSTITUTION: This slime controlling agent for papermaking is prepared by dissolving 0.1-50 pts.wt., preferably 5-30 pts.wt. of o-phthalaldehyde of the formula in propylene carbonate or a solvent obtained by blending it with another organic solvent in the weight ratio of <=1/2 to adjust to 100 pts.wt. of the total.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a stabilized o-form useful as a slime control agent in industrial water in a papermaking process.
Regarding phthalaldehyde preparations.

[0002]

2. Description of the Related Art It is known that o-phthalaldehyde has a remarkably excellent slime control action as a papermaking (industrial) bactericide (JP-A-6-264397). O-phthalaldehyde is dissolved in diethylene glycol monomethyl ether, which is a glycol solvent, to form a liquid preparation, or used as an aqueous suspension.

[0003]

However, in the case of o-phthalaldehyde solution or water suspension, it cannot be said that stability at high temperature and long-term storage is not always good, and coloring of the solution,
There is a decrease in active ingredient. Therefore, the value of the product is reduced due to the coloring of the product and the reduction of the slime control effect. The present invention has been made under such circumstances, and an object thereof is to provide an o-phthalaldehyde preparation having improved stability.

[0004]

Means for Solving the Problems As a result of intensive studies on organic compounds capable of stabilizing o-phthalaldehyde, the present inventors have found that o-phthalaldehyde can be dissolved in propylene carbonate or a solvent mainly containing it. According to the above, it was found that a liquid formulation having extremely high stability can be obtained even when a high concentration of o-phthalaldehyde is contained,
The present invention has been completed.

The present invention has the following formula (I)

Embedded image It is a slime control agent for papermaking in which o-phthalaldehyde represented by the following is dissolved in propylene carbonate or a solvent composed mainly of propylene carbonate.

The slime control agent for papermaking of the present invention can be prepared by mixing o-phthalaldehyde and propylene carbonate or a solvent mainly containing this. The solvent containing propylene carbonate as a main component means a solvent containing an organic solvent other than propylene carbonate in a ratio of about ½ (weight ratio) or less of propylene carbonate. Examples of such organic solvents include aromatic hydrocarbons such as benzene, toluene and xylene, esters such as ethyl acetate, butyl acetate, ethyl adipate and ethyl lactate, alcohols such as methanol and ethanol,
Glycols such as ethylene glycol, polyethylene glycol, diethylene glycol, diethylene glycol monomethyl ether, cellosolves, dimethylacetamide, dimethylformamide, dimethylsulfoxide, dioxane, chloroform and the like are used.

The slime control agent for papermaking of the present invention may be combined with other fungicides. Examples of the other fungicides include the following compounds. 2,2-dibromo-2-nitroethanol, 2-bromo-2-nitropropanediol-1,3,2-bromo-2-nitro-1,3-diacetoxypropane, 2,2-dibromo-2-nitro -1-acetoxyethane, methylenebisthiocyanate, 4,5
-Dichloro-1,2-dithiol-3-one, 2,2-
Dibromo-3-nitrilopropionamide, 1,2-bis-bromoacetoxyethane, 1,4-bis-bromoacetoxyethane-2-butene, 1,2-bis-bromoacetoxypropane, 1,2-benzisothiazoline-3
-One, 3,3,4,4-tetrachlorotetrahydrothiophene-1,1-dioxide, α-bromo-3-nitroacetophenone, α-chloro-benzaldoxime,
α-chloro-o-acetylbenzaldoxime, α-chloro-p-chlorobenzaldoxime, α-chloro-o
-Acetyl-p-chlorobenzaldoxime and the like.

The content of o-phthalaldehyde in the preparation of the present invention is usually 0.1 to 50 parts by weight (50 to 99.9 parts by weight of solvent), particularly 5 to 30 parts by weight in view of the stability of the preparation. It is preferable that the amount of the solvent is 70 to 95 parts by weight. The o-phthalaldehyde preparation of the present invention has good stability at high temperature and long-term storage, and is effective in controlling slime in industrial water in the paper manufacturing process.

[0009]

EXAMPLES Parts in the following formulation examples mean parts by weight. Formulation Example 1 10 parts of o-phthalaldehyde was added to 90 parts of propylene carbonate and dissolved by stirring to obtain a solution. Formulation Example 2 20 parts of o-phthalaldehyde was added to 80 parts of propylene carbonate and dissolved by stirring to obtain a solution. Formulation Example 3 30 parts of o-phthalaldehyde was added to 70 parts of propylene carbonate and dissolved by stirring to obtain a solution.

Comparative Example 1 10 parts of o-phthalaldehyde was added to 90 parts of diethylene glycol monomethyl ether and dissolved by stirring to obtain a solution. Comparative Example 2 10 parts of o-phthalaldehyde was mixed with 90 parts of ethylene glycol.
A part was added and dissolved by stirring to obtain a solution. Comparative Example 3 10 parts of o-phthalaldehyde was mixed with 9 parts of diethylene glycol.
0 part was added and dissolved by stirring to obtain a solution.

[Stability Test] 40 ml each of the solutions of Formulation Examples 1 to 3 and Comparative Examples 1 to 3 were placed in a 50 ml transparent glass bottle.
It was taken and sealed, and these were used as reagent reagents. Immediately after preparation and after storage in a thermostat at a temperature of 50 ° C. for 30 days, the stability was evaluated from the change in appearance and the residual ratio of o-phthalaldehyde. The residual ratio of o-phthalaldehyde is HP
It was measured by LC. Table 1 shows the results. The symbols in the table are as follows. A: The appearance rate is unchanged, and the residual rate is 95% or more. B: Afterimage ratio is 70 to 95% with no change in appearance. C: Coloring occurred and the residual rate was less than 70%.

[0012]

[Table 1]

Test Example 2 300 ml of white water collected from the corrugated fiberboard core papermaking process was placed in an Erlenmeyer flask, and the reagent was added to the white water at 5, 20 p.
Add to pm. After plugging with a paper stopper and shaking tow at 32 ° C. for 1 hour, the viable cell count was measured. At the same time, white water without addition of chemicals was also tested, and the bactericidal activity was compared by the degree of reduction in viable cell count due to addition of chemicals. Formulation Examples 1 to 3 were used as the test reagents. The test results are shown in Table 2. The formulations in the table are the same as in Test Example 1.

[0014]

[Table 2]

[0015]

The slime control agent for papermaking of the present invention is o-
It is capable of stabilizing phthalaldehyde and shows no decrease in efficacy even after long-term storage, and is extremely useful in practice as a slime control agent for papermaking.

Claims (2)

[Claims] 1. The following formula (I): A slime control agent for papermaking, wherein o-phthalaldehyde represented by the following is dissolved in propylene carbonate or a solvent composed mainly of propylene carbonate. 2. The paper-making slime control agent according to claim 1, which comprises 0.1 to 50 parts by weight of o-phthalaldehyde and 50 to 99.9 parts by weight of propylene carbonate or a solvent mainly containing propylene carbonate.