JPH1112970A - Pulp digesting assistant composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous slurry of anthraquinones at a high concentration useful as a pulp digesting assistant. SOLUTION: This pulp digesting assistant composition is an aqueous slurry of anthraquinones comprising a powder of the anthraquinones having <=10 μm average particle diameter and <=30 μm maximum particle diameter, an anionic surfactant, a nonionic surfactant which is a copolymer consisting essentially of an alkoxypolyalkylene glycol (meth)acrylate and an alkyl (meth)acrylate and water as essential constituent elements.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a pulp cooking aid composition comprising an anthraquinone aqueous slurry liquid. More specifically, the present invention relates to a pulp digestion aid composition which is a long-term stable anthraquinone aqueous slurry liquid containing anthraquinone powder, anionic surfactant, nonionic surfactant and water as essential components. About.

[0002]

2. Description of the Related Art In recent years, anthraquinones have been used as a pulp digestion aid, that is, as a redox catalyst, in addition to the use of dyes and pigments, to improve the productivity by shortening the digestion time and to reduce the digestion temperature. It is known that it is effective in improving pulp yield and quality while reducing energy and chemicals used.

However, anthraquinones are water-insoluble powders, and when added to the cooking liquor as it is, most of the anthraquinones float on the surface of the liquid, so that they are dispersed and dissolved in the cooking liquor within the usual cooking time. Is insufficient, and as a result, there is a problem that the effect as a cooking aid is not sufficiently exhibited.

As a method for solving the above problem, there is a method using tetrahydroanthraquinone which is a reduced form of anthraquinone which is soluble in an alkaline aqueous solution. The method is excellent in that tetrahydroanthraquinone can be dispersed and dissolved in the pulp cooking liquor quickly, but the tetrahydroanthraquinone in the alkaline aqueous solution is oxidized when brought into contact with air and precipitates as anthraquinone crystals. In transport and storage, nitrogen gas or an inert gas such as immiscible kerosene or liquid must block the contact with air.On the other hand, tetrahydroanthraquinone in an alkaline aqueous solution is transported and stored because it is a dilute solution. However, there is a problem that the cost related to is increased.

As another method, when anthraquinone is used as a powder, an anionic surfactant, particularly an anionic surfactant, is added to the anthraquinone powder to facilitate dispersion and dissolution in the pulp cooking liquor. An aqueous dispersion composition obtained by kneading an activator is disclosed (JP-B 61-6005).
No. 9). In the method for producing the composition for water dispersion, a paste having an anthraquinone content of about 30%, which is a composition of an anthraquinone powder and a surfactant, is uniformly dispersed in water,
In addition, it is described that the dispersion state is stable, but the stability of the slurry composition itself is described only after 15 hours, and it is hard to say that it is sufficient.

Further, Japanese Patent Application Laid-Open No. 55-6585 discloses a paste containing 50 to 60% of anthraquinone, which is a composition of an anthraquinone powder and a surfactant. All of the specific examples of the surfactant used in the method for producing the composition are only anionic surfactants, and the amount used is as large as 2% by weight or more in the paste. It is essential to uniformly disperse anthraquinone as a slurry liquid and add it to the digester,
As the anthraquinone concentration increases, the stability of the dispersion system is impaired. Although hard cake formation of the settled particles after several weeks does not occur, the practical problems of sedimentation separation and phase separation have not been solved yet.

[0007] WO 95/29288 discloses an aqueous dispersion of a composition of anthraquinones and rosin treated with a polyvalent metal salt. In the method for producing the aqueous dispersion, anthraquinone particles are surface-treated with a rosin alkali metal salt, and are thickened with a water-soluble polymer such as polyvinyl alcohol in order to supplement the stability of the aqueous dispersion. However, as disclosed by himself, the adsorption rate of the rosin alkali metal salt to anthraquinone is low, and sufficient stability has not been obtained even when a nonionic surfactant is used in combination. It is necessary to add a polyvalent metal salt in order to increase the adsorption rate of rosin alkali metal salt to anthraquinone, and the addition of a polyvalent metal salt such as calcium increases the scale formation in the digestion step, the bleaching step, the papermaking step, etc. It is not possible to adopt it for practical use.

[0008]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a high-concentration anthraquinone aqueous slurry useful as a pulp digestion aid, and furthermore to provide a good stability of the anthraquinone aqueous slurry. An object of the present invention is to realize economic advantages such as improvement in ease of handling and workability, and reduction in transportation costs due to high concentration. By uniformly dispersing and stabilizing the anthraquinones, the function of the anthraquinones as a cooking aid can be sufficiently exhibited.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies on pulp digestion aid compositions to achieve the above object, and have found that anthraquinone powders, anionic surfactants and nonionic surfactants By preparing a high-concentration anthraquinone aqueous slurry solution comprising water and water, the present inventors have found that a pulp digestion aid composition that solves the above problems can be obtained, and has completed the present invention.

That is, the objects of the present invention are as follows:
This is achieved by (7).

(1) Anthraquinone powder having an average particle diameter of 10 μm or less and a maximum particle diameter of 30 μm or less, an anionic surfactant, alkoxypolyalkylene glycol (meth)
A pulp digestion aid composition which is an anthraquinone aqueous slurry liquid containing a nonionic surfactant which is a copolymer containing acrylate and alkyl (meth) acrylate as essential components, and water as an essential component.

(2) The pulp digestion aid composition according to (1), wherein the amount of the anthraquinone powder used is 20 to 80% by weight.

(3) The anionic surfactant is at least one compound selected from the group consisting of aromatic sulfonates, aromatic sulfonate formalin condensates, and dialkyl sulfosuccinate salts.
Or the pulp cooking aid composition according to (2).

(4) The pulp digestion aid composition according to any one of (1) to (3), wherein the amount of the anionic surfactant used is 0.01 to 0.5% by weight.

(5) The nonionic surfactant is an alkoxypolyalkylene glycol (meth) acrylate alkoxylated with an alkyl group having 1 to 3 carbon atoms and a (meth) acrylate having an alkyl group having 4 to 30 carbon atoms. The pulp digestion aid composition according to the above (1), wherein the pulp digestion aid composition is at least one compound selected from the group consisting of copolymers containing as an essential component.

(6) The pulp digestion according to any one of the above (1) to (5), wherein the nonionic surfactant is a compound comprising a copolymer of methoxypolyethylene glycol acrylate and dodecyl acrylate. Auxiliary composition.

(7) The above (1) or (5) wherein the amount of the nonionic surfactant used is 0.01 to 0.5% by weight.
The pulp digestion aid composition according to any one of (1) to (6).

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

The anthraquinones used in the present invention include, for example, anthraquinone, 1,4-dihydroanthraquinone, 1,4-dihydroanthraquinol,
4,4a, 9a-tetrahydroanthraquinone, 1,
2,3,4-tetrahydroanthraquinone and anthrone.

The powder of anthraquinone used in the present invention has an average particle size of 10 μm or less, preferably 7 μm or less, and a maximum particle size of 30 μm or less, preferably 20 μm.
These are: If the average particle size is greater than 10 μm or the maximum particle size exceeds 30 μm, the dispersion stability of the resulting anthraquinone aqueous slurry is impaired.

The amount of the anthraquinone powder used in the present invention is adjusted so that the concentration of the anthraquinone in the anthraquinone aqueous slurry is in the range of 20 to 80% by weight. In consideration of the above, 40 to 80% by weight is more preferable. When the amount of the anthraquinone powder is less than 40% by weight, it is economically disadvantageous in terms of transportation costs, and when it exceeds 80% by weight, the viscosity increase and dispersion stability are disadvantageous. It is not preferable because it is difficult.

The anionic surfactant used in the present invention is not particularly limited, but is preferably selected from the group consisting of aromatic sulfonates, aromatic sulfonate formalin condensates, and dialkyl sulfosuccinate esters. At least one compound selected from the group consisting of sodium dodecylbenzenesulfonate, sodium 2-naphthalenesulfonate, sodium p-toluenesulfonate, sodium anthraquinone-2-sulfonate, sodium anthraquinone-disulfonate,
Examples include sodium salts of β-naphthalenesulfonic acid formalin condensate, sodium dioctylsulfosuccinate, sodium alkylnaphthalenesulfonate, alkyldiphenyl ether, sodium disulfonate and sodium bisnaphthalenesulfonate. More preferably, it is at least one compound selected from the group consisting of alkyl benzene sulfonate, anthraquinone sulfonate, naphthalene sulfonate formalin condensate and dialkyl sulfosuccinate salt, and among them, sodium anthraquinone-2-sulfonate Salts, sodium anthraquinone-disulfonate and naphthalene sulfonate formalin condensates are particularly desirable.

The amount of the anionic surfactant to be used is such that the concentration of the anionic surfactant in the aqueous slurry of anthraquinone is 0.01 to 0.5% by weight, preferably 0.03 to 0.3%.
It is prepared in the range of weight%. When the amount of the anionic surfactant is less than 0.01% by weight, the dispersion stability becomes insufficient, and when the amount exceeds 0.5% by weight, it is economically disadvantageous. Absent.

The nonionic surfactant used in the present invention is a copolymer containing alkoxypolyalkylene glycol (meth) acrylate and alkyl (meth) acrylate as essential components. Preferably, the nonionic surfactant comprises, as essential components, an alkoxypolyalkylene glycol (meth) acrylate alkoxylated with an alkyl group having 1 to 3 carbon atoms and a (meth) acrylate having an alkyl group having 4 to 30 carbon atoms. It is at least one compound selected from the group consisting of copolymers. Examples of the alkyl (meth) acrylate include lauryl (meth) acrylate, stearyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, and t-butyl (meth) acrylate. , Iso-butyl (meth) acrylate, cetyl (meth) acrylate and n-butyl (meth) acrylate. Further, the alkoxypolyalkylene glycol (meth) alkoxylated with the alkyl group having 1 to 3 carbon atoms
Examples of the polyalkylene glycol residue of the acrylate include polyethylene glycol, polypropylene glycol, polybutylene glycol, and the like, and a block copolymer thereof. More preferably, as the nonionic surfactant, the content of methoxypolyethylene glycol acrylate having 5 to 30 mol of polyalkylene oxide repeating units is 40 to 97% by weight, and the content of dodecyl acrylate is 3 to 60% by weight.
It is at least one copolymer selected from the group consisting of copolymers having a total content of both monomers of 70% by weight or more, among which methoxypolyethylene having a polyalkylene oxide repeating unit number of 5 to 30 mol. It is selected from the group consisting of copolymers having a glycol acrylate content of 40 to 97% by weight, a dodecyl acrylate content of 3 to 60% by weight, and a weight average molecular weight in the range of 1,000 to 500,000. At least one copolymer is particularly desirable. The nonionic surfactant may contain, for example, an auxiliary for dissolution or a component such as ethylene glycol or toluene for the purpose of facilitating handling, in addition to the essential component.

The amount of the nonionic surfactant used is such that the concentration of the nonionic surfactant in the anthraquinone aqueous slurry is 0.01 to 0.5% by weight, preferably 0.03 to 0.3%.
It is prepared in the range of weight%. When the amount of the nonionic surfactant is less than 0.01% by weight, the dispersion stability becomes insufficient. When the amount exceeds 0.5% by weight, it is economically disadvantageous. Absent. In addition, the synthesis of the nonionic surfactant may be a known polymerization method, and is not particularly limited.

The amount of water used in the present invention is such that the anthraquinone aqueous slurry has a water concentration of 20 to 80% by weight,
It is preferably prepared in the range of 20 to 60% by weight. If the amount of the water is less than 20% by weight, the dispersion stability becomes insufficient or the viscosity increases, which causes a practical obstacle. It is not preferable because it is economically disadvantageous.

The pulp digestion aid composition, which is an anthraquinone aqueous slurry liquid of the present invention, may contain, if necessary, a bio-gum of a microbial acidic polysaccharide called a fermented polysaccharide bio-gum as a dispersion stabilizer. You may. For example,
It is a polysaccharide gum such as xanthan gum. Furthermore, clay and silica derivatives typified by sodium carboxymethylcellulose, guar gum, gum arabic, sodium alginate, polyvinyl alcohol, montmorillonite and the like may be contained. The presence of these dispersion stabilizers is useful for adjusting the viscosity and rheology of the anthraquinone aqueous slurry liquid, suppressing sedimentation of the anthraquinone-like particles, and stabilizing the dispersion of the aqueous slurry liquid for a long period of time.

The amount of the above-mentioned dispersion stabilizer to be used is adjusted so that the concentration of the dispersion stabilizer in the aqueous anthraquinone slurry is 0.01 to 5% by weight, preferably 0.05 to 2% by weight.
When the use amount of the dispersion stabilizer is less than 0.01% by weight, the dispersion stability becomes insufficient. When the use amount exceeds 5% by weight, the viscosity of the anthraquinone aqueous slurry liquid increases, causing various obstacles in practical use. And economically disadvantaged.

The pulp digestion aid composition, which is the aqueous anthraquinone slurry of the present invention, may further contain, if necessary, a water-soluble aqueous solution having a molecular weight of 200 or less, preferably 130 or less for the purpose of lowering the freezing temperature of the anthraquinone aqueous slurry. Alcohols may be contained. Examples of the water-soluble alcohols having a molecular weight of 200 or less include methanol,
Lower monohydric alcohols such as ethanol, propanol and isopropanol, and dihydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, 1,3-butylene glycol, neopentyl glycol and the like. No.

The amount of the water-soluble alcohol used is adjusted so that the concentration of the water-soluble alcohol in the anthraquinone aqueous slurry is in the range of 1 to 5% by weight, preferably 1 to 3% by weight. If the amount of the water-soluble alcohol is less than 1% by weight, the effect of lowering the freezing temperature of the aqueous solution of anthraquinone cannot be sufficiently exerted. Is unfavorable because it may affect the long-term stabilization mechanism.

Further, the pulp digestion aid composition which is the aqueous slurry of anthraquinone of the present invention may contain a known preservative or disinfectant for the purpose of preventing spoilage, if necessary. Examples of known preservatives or bactericides used for the purpose of preventing spoilage include, for example, sodium pentachlorophenolate, aromatic alcohols of paraformaldehyde (such as benzyl alcohol), formaldehyde, isothiazolines, and brominated nitropropanediol. Can be

The amount of the preservative or fungicide used is such that the concentration of the preservative or fungicide in the anthraquinone aqueous slurry is 0.01 to 0.2% by weight, preferably 0.02 to 0.1%.
It is prepared in the range of weight%. If the amount of the preservative or bactericide is less than 0.01% by weight, its function is insufficiently exhibited, and the object cannot be achieved. On the other hand, if it exceeds 0.2% by weight, it is not preferable because it affects the mechanism of other additives or is economically disadvantageous.

Next, specific embodiments of the present invention will be described.

When a predetermined amount of an anionic surfactant, a nonionic surfactant and distilled water are stirred with a stirrer having a sufficient stirring ability, the average particle size is 10 μm or less and the maximum particle size is 30 μm or less. A predetermined amount of anthraquinone powder is gradually added, and then a predetermined amount of a dispersion stabilizer is added and maintained for a certain period of time. At the time of stirring, if necessary, a water-soluble alcohol having a molecular weight of 200 or less for the purpose of lowering the freezing temperature of the aqueous solution of anthraquinone slurry, or a known antiseptic or a disinfectant for the purpose of preventing spoilage, is prepared. Is also possible.

The method of preparing the anthraquinone aqueous slurry liquid may be such that anthraquinones or the like may be prepared directly by a wet method using a general stirrer such as a homomixer or an attritor or a high-pressure emulsifier, or may be prepared in advance by a dry method. A wet powder in which anthraquinones, activators, and the like are uniformly mixed may be prepared using a ball mill, a kneader, or the like, and the slurry may be adjusted using an ordinary stirring tank or the like immediately before addition to the cooking step.

[0036]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples, but it goes without saying that the present invention is not limited to only these Examples.

<Preparation of Anthraquinone Water Slurry> Predetermined amounts of anionic surfactant, nonionic surfactant and distilled water were collected in a 500 ml beaker, and homomixer manufactured by Tokushu Kika Kogyo Co., Ltd .; K. Auto Homo Mixer M
While stirring with a mold, a predetermined amount of anthraquinone powder is gradually added in 5 minutes, and then a predetermined amount of a dispersion stabilizer is added and maintained for 30 minutes.

<Measurement of Viscosity> The viscosity of the prepared anthraquinone aqueous slurry liquid was measured using a B-type viscometer DIGITAL VISCOMETER DVL- manufactured by Tokyo Seiki Co., Ltd.
B, the rotor No. It was measured at 3, 60 rpm and 25 ° C.

<Evaluation of Stability> The stability of the aqueous anthraquinone slurry was evaluated in five steps from good (も の) to 25% (1 month) immediately after the preparation and no effect (XX). (◎, ○, Δ, ×, XX) were evaluated.

<Measurement of Particle Size of Anthraquinone Powder> After preparing an anthraquinone aqueous slurry, a laser diffraction / scattering particle size distribution analyzer (MICROTR manufactured by Nikkiso Co., Ltd.)
AC HRA), and the average particle size indicates a volume average particle size.

Reference Example 1 (Production Example of Nonionic Surfactant Polymer) A flask equipped with a thermometer, a stirrer, two dropping funnels, a gas inlet tube and a reflux condenser was charged with 50 parts by weight of toluene. The atmosphere in the flask was replaced with nitrogen under stirring, and the flask was heated to 100 ° C. in a nitrogen stream. Thereafter, 80 parts by weight of methoxypolyethylene glycol acrylate (containing 9 moles of ethylene oxide units per molecule, average molecular weight 966) of 80 parts by weight, 20 parts by weight of dodecyl acrylate (molecular weight 240) while maintaining the same temperature under a nitrogen stream. A monomer mixed solution consisting of 50 parts by weight of toluene was added dropwise over 120 minutes, and at the same time, a polymerization initiator solution consisting of 1.5 parts by weight of azobisisobutyronitrile and 50 parts by weight of toluene was added from the other dropping funnel for 180 minutes. It dripped over. After the completion of the dropwise addition, the temperature was further maintained at the same temperature for 60 minutes to complete the polymerization.

At this time, the polymerization rate of each monomer was 98% for methoxypolyethylene glycol acrylate and 99% for dodecyl acrylate, and the average molecular weight of the obtained polymer was 20,000. Thereafter, the toluene solvent was distilled off under reduced pressure to obtain a nonionic surfactant polymer (1). The average molecular weight of the polymer is a weight average molecular weight measured by GPC and calculated in terms of polystyrene.

Reference Example 2 (Production Example of Nonionic Surfactant Polymer) A nonionic surfactant polymer was synthesized in the same manner as in Reference Example 1. However, the amount was changed to 70 parts by weight of methoxypolyethylene glycol acrylate (containing an average of 9 mol of ethylene oxide units per molecule, average molecular weight of 966), 30 parts by weight of dodecyl acrylate (molecular weight 240) and 50 parts by weight of toluene. At this time, the polymerization rate of each monomer was 9% for methoxypolyethylene glycol acrylate.
9% and dodecyl acrylate were 99%, and the obtained polymer had a polystyrene reduced weight average molecular weight of 25,000. Thereafter, the toluene solvent was distilled off under reduced pressure to obtain a nonionic surfactant polymer (2).

Example 1 125.0 g of anthraquinone having an average particle size of 8.4 μm and a maximum particle size of 22.0 μm, and 0.19 of an anionic surfactant containing 82% of sodium anthraquinone-2-sulfonate
0 g, 0.156 g of a copolymer of methoxypolyethylene glycol acrylate and dodecyl acrylate (nonionic surfactant polymer (1) obtained in Reference Example 1), 6.75 g of ethylene glycol and 0.43 of xanthan gum
The amount was 8 g, and the anthraquinone aqueous slurry was prepared by using the remaining amount as distilled water so that the total amount was 250 g. The viscosity of the obtained anthraquinone aqueous slurry liquid is 870 mPa · s
The stability after one month had been good.

Example 2 An anthraquinone aqueous slurry was prepared in the same manner as in Example 1. However, as the nonionic surfactant, the nonionic surfactant polymer (2) obtained in Reference Example 2 was used, and as the anionic surfactant, sodium naphthalene sulfonate formalin condensate was used. The viscosity of the obtained anthraquinone aqueous slurry was 920 mPa · s, and the stability after one month had passed was good.

Comparative Example 1 The average particle size was 14.8 instead of the anthraquinone of Example 1.
The same procedure as in Example 1 was carried out except that anthraquinone having a maximum particle size of 35.6 μm was used. Table 1 shows the results of the viscosity and dispersion stability of the obtained anthraquinone aqueous slurry liquid.

Comparative Examples 2-3 The anionic surfactant containing sodium anthraquinone-2-sulfonate of Example 1 or the nonionic surfactant polymer of methoxypolyethylene glycol acrylate and dodecyl acrylate (obtained in Reference Example 1) The same procedure as in Example 1 was carried out except that the nonionic surfactant polymer (1)) was not added. However, the amount of the activator added was twice the amount of Example 1. Table 1 shows the results of the viscosity and dispersion stability of each of the obtained anthraquinone aqueous slurry liquids.

[0048]

[Table 1]

From the results of Examples 1 and 2 and Comparative Examples 1 to 3 shown in Table 1, as the particle size of anthraquinone increases, the sedimentation property and slurry viscosity are affected, and the stability is also deteriorated.
In addition, anionic or nonionic surfactant polymer alone gives insufficient results in dispersibility and stability.

Example 3 175.0 g of anthraquinone having an average particle diameter of 8.4 μm and a maximum particle diameter of 22.0 μm, and an anionic surfactant 0.21 containing 82% of sodium anthraquinone-2-sulfonate
3 g, 0.263 g of a copolymer of methoxypolyethylene glycol acrylate and dodecyl acrylate (the nonionic surfactant polymer (1) obtained in Reference Example 1) and 6.75 g of ethylene glycol, and the remaining amount was 250 g. An anthraquinone aqueous slurry was prepared using distilled water as the amount. The viscosity of the obtained anthraquinone aqueous slurry liquid was 1,830 mPa · s, and the stability after one month had passed was good.

COMPARATIVE EXAMPLES 4-5 Except that the anionic surfactant containing sodium anthraquinone-2-sulfonate of Example 3 or the nonionic surfactant polymer of methoxypolyethylene glycol acrylate and dodecyl acrylate was not added. Performed as in Example 3. However, the amount of the activator added was twice the amount of Example 3. Table 2 shows the results of the viscosity and dispersion stability of the obtained anthraquinone water slurries.

[0052]

[Table 2]

Example 3 and Comparative Examples 4 to 4 shown in Table 2 above
From the results of 5, the anionic or nonionic surfactant polymer alone gives insufficient results in dispersibility and stability as in Comparative Examples 2 and 3.

Comparative Example 6 125.0 g of anthraquinone having an average particle size of 8.4 μm and a maximum particle size of 22.0 μm, and disproportionated rosin potassium salt 12.5
g and ethylene oxide 30 mole addition rosin 6.25
g, 75 g of distilled water was added and dispersed, and then a solution of 1.25 g of calcium chloride dissolved in 12.5 g of distilled water was slowly added dropwise at 50 ° C. Furthermore, polyvinyl alcohol6.
An aqueous solution obtained by dissolving 25 g in predetermined distilled water was added. The resulting dispersion had an anthraquinone content of 50% and a viscosity of 31.
It was 0 mPa · s.

Comparative Example 7 Instead of adding the aqueous calcium chloride solution of Comparative Example 6,
The procedure was performed in the same manner as in Comparative Example 6 except that 13.75 g of distilled water was added.

Comparative Example 8 Instead of adding the anionic surfactant containing sodium anthraquinone-2-sulfonate of Example 1 and the copolymer of methoxypolyethylene glycol acrylate and dodecyl acrylate, naphthalenesulfonic acid formalin condensate 4 was used instead. The procedure was performed in the same manner as in Example 1 except that 0.0 g was added. However, the amount of the activator added was twice the amount of Example 1.

Comparative Example 9 Instead of adding the anionic surfactant containing sodium anthraquinone-2-sulfonate of Example 1 and the copolymer of methoxypolyethylene glycol acrylate and dodecyl acrylate, 19.0 g of sodium ligninsulfonate was used. Was carried out in the same manner as in Example 1 except that was added. However, the amount of the activator added was 2 in Example 1.
Double the amount.

Table 3 shows the results of the viscosity and dispersion stability of the aqueous anthraquinone slurries obtained in Comparative Examples 6 to 9, respectively.

[0059]

[Table 3]

Example 1 and Comparative Examples 6 to 6 shown in Table 3 above
9, the combination of disproportionated rosin potassium salt and ethylene oxide 30 mol added rosin was converted to a polyvalent metal salt (C
(a salt) treatment is insufficient in stability even if the influence of an increase in calcium scale, which is an important obstacle in the cooking step, is ignored.

In the combination of disproportionated rosin potassium salt and ethylene oxide 30 mol added rosin, the surface treatment of anthraquinone particles with disproportionated rosin potassium salt is insufficient, and dispersibility and stability cannot be secured with ethylene oxide 30 mol added rosin. .

With only the anionic surfactant of naphthalenesulfonic acid formalin condensate or sodium ligninsulfonate, even if the viscosity is increased by the addition of xanthan gum or polyvinyl alcohol, phase separation or a hard cake is formed in the long term.

[0063]

The pulp cooking aid composition obtained according to the present invention comprises the above-mentioned anthraquinone powder of the prior art,
Higher concentration than anthraquinone paste or tetrahydroanthraquinone which is soluble in alkaline aqueous solution,
In addition, it consists of an anthraquinone aqueous slurry liquid with good stability, fully demonstrates the performance of anthraquinone as a cooking aid, and is economical to achieve easy handling, improved workability, and reduced transportation costs. Excellent composition.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshinori Saito 9-1, Takayashinmachi, Ichikawa-shi, Chiba Japan Nippon Distillery Co., Ltd.

Claims (7)

[Claims] 1. An average particle diameter of 10 μm or less, and a maximum particle diameter of 30 μm.
m, an anthraquinone powder or less, an anionic surfactant, a nonionic surfactant which is a copolymer containing alkoxypolyalkylene glycol (meth) acrylate and alkyl (meth) acrylate as essential components, and water as essential components A pulp cooking aid composition which is an anthraquinone aqueous slurry liquid. 2. The pulp cooking aid composition according to claim 1, wherein the amount of the anthraquinone powder used is 20 to 80% by weight. 3. The compound according to claim 1, wherein the anionic surfactant is at least one compound selected from the group consisting of aromatic sulfonates, aromatic sulfonate formalin condensates, and dialkyl sulfosuccinate salts.
A pulp cooking aid composition according to any one of the above. 4. The amount of the anionic surfactant used is:
The pulp cooking aid composition according to any one of claims 1 to 3, which is 0.01 to 0.5% by weight. 5. The nonionic surfactant according to claim 1, wherein the nonionic surfactant has 1 to 1 carbon atoms.
An alkoxypolyalkylene glycol (meth) acrylate alkoxylated with an alkyl group having 3 to 3 carbon atoms;
The pulp digestion aid composition according to claim 1, which is at least one compound selected from the group consisting of copolymers comprising (meth) acrylate having an alkyl group of 30 as an essential component. 6. The pulp digestion aid composition according to claim 1, wherein the nonionic surfactant is a compound consisting of a copolymer of methoxypolyethylene glycol acrylate and dodecyl acrylate. . 7. The use amount of the nonionic surfactant is as follows:
The pulp cooking aid composition according to any one of claims 1, 5 to 6, wherein the content is 0.01 to 0.5% by weight.