JP6216957B2 - Pitch control agent for papermaking process and pitch failure prevention method - Google Patents

Description

  The present invention is used in a papermaking process, suppresses the adhesion of pitch to production equipment and pulp, and prevents a pitch product from being deteriorated due to the pitch (also referred to as a “pitch disturbance inhibitor”) and It relates to a method using it.

  Conventionally, in order to suppress and prevent the occurrence of obstacles due to pitch in the paper and pulp manufacturing process, various drugs have been developed. This pitch is a water-insoluble adhesive substance mainly composed of organic substances derived from natural resins and gum substances released from wood, pulp and paper, as well as additives used in the manufacturing process of paper and pulp. Say.

  In general, pitch is dispersed in a colloidal form in white water of the paper and pulp manufacturing process, but some external action such as large shear force, rapid pH change, sulfate band (aluminum sulfate) It is considered that the colloidal state is destroyed due to the excessive addition of, etc., and aggregates and enlarges. This agglomerated and enlarged pitch not only adheres to paper and pulp, but also to manufacturing equipment such as paper, pulp, fan pumps, pipes, chests, wires, felts, rolls, etc. And re-adheres to paper and pulp. The spots and defects of the paper formed in this way deteriorate the quality of the paper product. Further, the generated paper breakage causes a failure such as a decrease in productivity and workability. In recent years, with the diversification of paper, the types and usage of additives have increased, and as the use of water in the manufacturing process has become more closed, the occurrence of pitch disturbance has increased and the occurrence has increased. The form is complicated.

As a method for suppressing such pitch failure, a method of adsorbing pitch components to inorganic compounds such as fine talc, a method of fixing pitch particles before agglomeration to pulp fibers, a method of dispersing pitch particles, and a combination thereof Have been put to practical use.
For example, Japanese Patent Application Laid-Open No. 2004-218118 (Patent Document 1) discloses a pitch control agent composed of a low viscosity cationized starch having a specific N value (mass% of nitrogen) and viscosity. .
However, the conventional additives and methods are not sufficient in preventing the pitch failure, and more effective drugs and methods are desired.

Japanese Patent Laid-Open No. 03-45799 (Patent Document 2) discloses a method for producing a neutral paper in which a water-soluble aluminum salt such as polyaluminum chloride, an amphoteric starch, a water-swellable cationic copolymer and bentonite are added. JP-A-63-27595 (Patent Document 3) adds a copolymer derived from a mixture of cationized starch and an amphoteric acrylamide polymer and a condensed hydrated aluminum salt such as polyaluminum chloride. A papermaking method is disclosed.
However, the above-described neutral paper manufacturing method and paper manufacturing method are intended to improve the yield in the paper manufacturing process, and the effect of preventing pitch disturbance under a high alkali atmosphere with a pH of about 10 has not been specifically studied. .

  In addition, although it is different from the subject of the present invention and there is no description about the effect of preventing the pitch failure in the papermaking process, JP 2012-531301 (Patent Publication 4) cationizes starch and the like. Disclosed is a composition for improved separation of paint and spray residues from water streams in the paint and surface treatment industry, comprising a component, a polybasic metal salt, such as an amphoteric salt of aluminum, and a polymer.

JP 2004-218118 A Japanese Patent Laid-Open No. 03-45799 Japanese Patent Laid-Open No. 63-275795 Special table 2012-531301 gazette

However, each of the additives used in the above prior art has problems.
For example, fine talc of an inorganic compound has a weak effect per mass and requires a high addition rate, which increases the cost. On the other hand, the amount of addition decreases according to the cost, and a sufficient pitch suppression effect can be obtained. There is a problem that it is difficult.
In addition, since the effect of preventing pitch failure is not sufficient, the additives and nonionic surfactants are used in a highly alkaline atmosphere having a pH of about 10 as in the case of adding to a pulp slurry that has been washed through a cooking process. When conventional pitch control agents such as an agent, a cationic polymer and fine talc are used, there is a problem that an excessive amount is required and the cost is increased.
Then, this invention makes it a subject to provide the pitch control agent for paper manufacture processes which can prevent efficiently the pitch obstruction which generate | occur | produces in a paper manufacture process, and the pitch obstruction prevention method using the same.

  The inventors of the present invention, as a result of intensive studies to solve the above problems, have found that a water-soluble aluminum compound such as highly basic aluminum chloride and a modified starch such as a hydroxypropylated starch degradation product, By using together at a specific ratio, it is possible to efficiently prevent the pitch failure occurring in the papermaking process due to their synergistic effect, and to find out the fact that the effect is sufficiently exerted even in a highly alkaline environment, and to complete the present invention. Arrived.

Thus, according to the present invention, one or more water-soluble aluminum compounds selected from polyaluminum chloride, highly basic aluminum chloride, aluminum hydroxide, hydroxyaluminum chloride, aluminum nitrate and aluminum sulfate , and starch , Hydroxyalkylated starch, carboxyalkylated starch, cationized starch, crosslinked starch and porous starch, and one or more starch components selected from degradation products thereof in a mass ratio of 1: 0. A pitch control agent for a papermaking process is provided, which is contained as an active ingredient at a blending ratio of 01 to 1: 3 .

  Further, according to the present invention, the pitch control agent as an active ingredient is added to the pulp slurry in the paper making process in an amount of 0.01 to 100 g / kg with respect to the mass of the absolutely dry pulp, and the quality of the paper product by the pitch. There is provided a pitch failure prevention method characterized by preventing a decrease.

  According to the present invention, it is possible to provide a pitch control agent for a papermaking process capable of efficiently preventing a pitch failure occurring in the papermaking process and a pitch failure prevention method using the same. That is, the pitch control agent for papermaking process of the present invention can obtain a high pitch failure prevention effect at a low addition rate, and can reduce the cost.

In addition, the pitch control agent for papermaking process of the present invention has at least one of the following requirements:
(1) The water-soluble aluminum compound is one or more selected from polyaluminum chloride, highly basic aluminum chloride, aluminum hydroxide, aluminum hydroxychloride, aluminum nitrate and aluminum sulfate. (2) Water-soluble aluminum The compound is one or more selected from polyaluminum chloride, highly basic aluminum chloride and aluminum sulfate. (3) The starch component is starch, hydroxyalkylated starch, carboxyalkylated starch, cationized starch, (4) The starch component is starch, dextrin, hydroxypropylated starch degradation product, cationized starch, hydroxya starch, or one or more selected from crosslinked starch and porous starch and degradation products thereof One or more selected from killed phosphoric acid crosslinked starch and porous starch (5) the water-soluble aluminum compound is highly basic aluminum chloride, and the starch component is a hydroxypropylated starch degradation product or It is a dextrin (6) When the blending ratio of the water-soluble aluminum compound and the starch component satisfies a mass ratio of 1: 0.01 to 1: 3, the above effect is further exhibited.

It is a figure which shows the synergistic effect of pitch obstacle prevention of highly basic aluminum chloride and a hydroxypropylated starch degradation product in the pulp slurry of pH 8.5. It is a figure which shows the synergistic effect of pitch obstacle prevention of the highly basic aluminum chloride and the hydroxypropylated starch degradation product in the pulp slurry of pH10. It is a figure which shows the synergistic effect of pitch obstacle prevention of the aluminum sulfate and hydroxypropylated starch degradation product in the pulp slurry of pH 8.5. It is a figure which shows the synergistic effect of pitch obstacle prevention of highly basic aluminum chloride and dextrin in the pulp slurry of pH 8.0. 2 is a schematic diagram of a pulp pitch adhesion tester used in Test Example 1. FIG.

(1) Pitch control agent for papermaking process The pitch control agent for papermaking process of the present invention has a synergistic effect between a water-soluble aluminum compound and a starch component selected from starch, modified starch, and degradation products thereof. It is contained as an active ingredient.

[Water-soluble aluminum compound]
The water-soluble aluminum compound used in the present invention is not particularly limited as long as it exhibits a synergistic effect with the starch component described later.
Examples of the water-soluble aluminum compound include polyaluminum chloride, highly basic aluminum chloride, aluminum hydroxide, hydroxyaluminum chloride, aluminum nitrate and aluminum sulfate. In the present invention, one of these is used alone. Alternatively, two or more kinds can be used in combination.
Among these, one or more selected from polyaluminum chloride, highly basic aluminum chloride, and aluminum sulfate are preferable from the viewpoint of the effect of preventing pitch disturbance.

Polyaluminum chloride and highly basic aluminum chloride are commercially available products with different concentrations in terms of Al ₂ O ₃ and basicity, and those having high concentrations are generally referred to as highly basic aluminum chloride.
Polyaluminum chloride is, for example, a basic aluminum chloride polymer [Al ₂ (OH) _a Cl _6-a ] _b obtained by dissolving aluminum hydroxide in hydrochloric acid, wherein a and b are basicity. And a is an integer of 1 to 5 and b is an integer of 10 or less), and is known as a water treatment flocculant. The basicity B (%) is represented by B = (a / 6) × 100 using the variable a and varies. Generally, the composition of B = 40 to 65% is commercially available and can be easily obtained.
The polyaluminum chloride may be synthesized by a known method, but may be a commercially available product as used in the examples.

Highly basic aluminum chloride is an inorganic ionic polymer formed by polycondensation of aluminum hydroxide Al _c (OH) _d Cl _3c-d (where c and d are variables depending on basicity, c Is generally an integer of 1 or more and less than 5, and d is an integer of 9 or less. Since it is a polynuclear complex, it has a higher positive charge than an aluminum monoatomic ion, and only 1/4 to 1/6 equivalent of an acid radical is contained in the molecule as compared with a normal aluminum salt. The basicity B (%) is represented by B = (d / 3c) × 100 using the variables c and d and varies. Generally, a composition having a composition of B = 70 to 85% is commercially available and can be easily obtained.
The highly basic aluminum chloride may be synthesized by a known method, but may be a commercially available product as used in the examples.

[Starch component]
The starch component used in the present invention is not particularly limited as long as it is selected from starch, modified starch, and degradation products thereof and exhibits a synergistic effect with the water-soluble aluminum compound described above.
Examples of the starch include starch (raw starch) subjected to purification treatment by a known method using corn, rice, wheat, potato (potato), tapioca, sweet potato and the like as raw materials.

  Modified starches include, for example, etherified starches such as hydroxyalkylated starch, carboxyalkylated starch, and cationized starch; esterified starches such as starch acetate, octenyl succinate starch and phosphate starch; cross-linked starch; grafted starch; porous Quality starch and the like.

Examples of the hydroxyalkylated starch include those obtained by introducing a hydroxyalkyl group into the above starch by etherification by a known method.
Here, alkyl has about 1 to 4 carbon atoms, and examples of the hydroxyalkylated starch include hydroxymethylated starch, hydroxyethylated starch, and hydroxypropylated starch.

Examples of the carboxyalkylated starch include those obtained by introducing a carboxyalkyl group into the above starch by etherification by a known method.
Here, the alkyl has about 1 to 4 carbon atoms, and examples of the carboxyalkylated starch include carboxymethylated starch, carboxyethylated starch, carboxypropylated starch and the like. Carboxymethylated starch is particularly preferable from the viewpoint of availability as a compound.

  Examples of the cationized starch include those obtained by cationizing the above starch by a known method.

Examples of the crosslinked starch include those obtained by crosslinking the above starch by a known method. Examples include phosphate distarch, glycerol distarch, and hydroxyalkylated phosphate cross-linked starch.
Here, alkyl has about 1 to 4 carbon atoms, and examples of the hydroxyalkylated phosphoric acid crosslinked starch include hydroxymethylated phosphoric acid crosslinked starch, hydroxyethylated phosphoric acid crosslinked starch, and hydroxypropylated phosphoric acid crosslinked starch. Of these, hydroxypropylated phosphoric acid crosslinked starch is particularly preferred from the viewpoint of the effect of preventing pitch disturbance and the availability as a compound.

  Examples of the porous starch include known methods such as those obtained by decomposing the above-mentioned starch or modified starch with an enzyme or acid, and drying to form a powder, such as those used in the examples. It may be.

Examples of the decomposition product of the starch component include a product obtained by hydrolyzing part or all of the starch component with an acid or an enzyme, preferably an enzyme.
Examples of the degradation product of the starch component include dextrin which is a low molecular weight hydrocarbon compound obtained by hydrolysis of the above starch.

The starch component may be synthesized (processed) by a known method, or may be a commercially available product as used in the examples.
In the present invention, one of the above starch components can be used alone or in combination of two or more.
Among the above-mentioned starch components, one or more selected from starch, hydroxyalkylated starch, carboxyalkylated starch, cationized starch, crosslinked starch and porous starch and their degradation products in terms of the effect of preventing pitch disturbance Two or more types are preferable, and one or more types selected from starch, dextrin, hydroxypropylated starch degradation product, cationized starch, hydroxyalkylated phosphate cross-linked starch and porous starch are more preferable. Preferably, hydroxypropylated starch degradation products and degradation products such as dextrin are particularly preferred from the standpoint of ease of formulation.
As described above, in the present invention, a combination in which the water-soluble aluminum compound is highly basic aluminum chloride and the starch component is a hydroxypropylated starch degradation product or dextrin is particularly preferable.

[Combination ratio]
The blending ratio of the water-soluble aluminum compound and the starch component, that is, the ratio in which both have a synergistic effect varies depending on the type of both and the conditions of addition (pH, temperature, etc.), but is usually 1: 0.01 by mass ratio. It is preferably ˜1: 3.
When the starch component is less than 0.01 with respect to the water-soluble aluminum compound 1, that is, when the high basic aluminum chloride is excessive, and when the starch component exceeds 3, that is, when the high basic aluminum chloride is too low, both In the former case, the pitch may agglomerate and precipitate excessively, and in the latter case, the agglomeration of the pitches cannot be prevented, which may hinder the subsequent process.
A more preferable blending ratio is 1: 0.01 to 1: 1 by mass ratio, and a particularly preferable range is 1: 0.01 to 1: 0.5.

The preferable mixture ratio in the combination of a specific water-soluble aluminum compound and starch component is listed.
A preferable blending ratio of the highly basic aluminum chloride and the hydroxypropylated starch degradation product (when added to a pulp slurry having a pH of 8.5) is 1: 0.01 to 1: 3 by mass ratio, and a particularly preferable range is 1: 0.1 to 1: 3.
A preferable blending ratio of the highly basic aluminum chloride and the hydroxypropylated starch degradation product (when added to a pulp slurry having a pH of 10) is 1: 0.01 to 1: 3 by mass ratio, and a particularly preferable range is 1: 0.1 to 1: 0.5.
A preferred blending ratio of aluminum sulfate and hydroxypropylated starch degradation product (when added to a pulp slurry having a pH of 8.5) is 1: 0.01 to 1: 3 by mass ratio, and a particularly preferred range is 1: 0. .1-1: 0.5.
A preferable blending ratio of highly basic aluminum chloride and dextrin (when added to a pulp slurry having a pH of 8.0) is 1: 0.01 to 1: 3 by mass ratio, and a particularly preferable range is 1: 0.1. ~ 1: 0.5.

[Pitch control agent for papermaking process]
The pitch control agent for papermaking process of the present invention is preferably formulated and used in the form of a normal liquid.
When it is set as a liquid agent, it is preferable to set it as the liquid agent which used water as a solvent.
The concentration of the liquid agent may be appropriately set depending on the concentration of pulp slurry to be added, the type and amount of pitch components, papermaking conditions, and the like, but is usually 10 to 500 g / kg.
When the solution concentration is less than 10 g / kg, it may be necessary to add a large amount of the solution to the addition target. On the other hand, when the liquid agent concentration exceeds 500 g / kg, it may be difficult to handle the liquid agent.
A preferred concentration is 50 to 500 g / kg.

(2) Pitch failure prevention method In the pitch failure prevention method of the present invention, 0.01 to 100 g / kg of the above pitch control agent as an active ingredient is added to the pulp slurry in the papermaking process with respect to the mass of the absolutely dry pulp. Thus, the quality of the paper product is prevented from being deteriorated due to the pitch.

When the addition amount of the pitch control agent is less than 0.01 g / kg, the effect of preventing the pitch failure may not be obtained sufficiently, which is not preferable. On the other hand, when the addition amount of the pitch control agent exceeds 100 g / kg, not only the pitch is agglomerated but also pulp fibers and fine fibers may agglomerate and may adversely affect the texture of the paper. . Depending on the type, amount, and papermaking conditions of the pitch component, there may be no adverse effects as described above. In such a case, the pitch control agent of the present invention is added beyond the above range. May be acceptable.
A preferable addition amount of the pitch control agent is 0.01 to 20 g / kg.

  The pitch failure prevention method of the present invention can be applied to a papermaking process in which a pitch failure has occurred or is likely to occur. Specifically, the purpose can be achieved by adding to the pulp slurry or white water at the stage where the pitch failure occurs in the papermaking process or at the previous stage.

  Examples of the addition method include a method of adding the pitch control agent of the present invention to a required concentration in the equipment in each stage of the papermaking process or the pipe connecting them.

  The present invention will be specifically described by the following formulation examples and test examples, but the present invention is not limited thereto.

In the formulation examples, the following compounds were used.
[Water-soluble aluminum compound]
・ Polyaluminum chloride: PAC
(30% by mass as content Al ₂ O ₃ , manufactured by Daimei Chemical Co., Ltd., product name: polyaluminum chloride powder pack, basicity: 40-60%)
・ Highly basic aluminum chloride: AA
(23.5 mass% as content Al ₂ O ₃ , manufactured by Taki Chemical Co., Ltd., product name: Takibaine # 1500, basicity: 82 to 85%)
・ Aluminum sulfate: AS
(Content Al ₂ (SO ₄ ) ₃ as 54% by mass, manufactured by Kishida Chemical Co., Ltd., product name: aluminum sulfate (14-18 water))

[Starch component]
・ Starch: St
(Content: 100% by mass, manufactured by Wako Pure Chemical Industries, Ltd., product name: starch, derived from corn)
・ Cationized starch: CS
(Content: 100% by mass, manufactured by Nippon Shokuhin Kako Co., Ltd., product name: Neotack # 30T)
・ Hydroxypropylated starch degradation product: HPS
(Content: 100% by mass, manufactured by Nissho Chemical Co., Ltd., product name: PENON PKW)
・ Dextrin: DS
(Content 100% by mass, manufactured by Matsutani Chemical Co., Ltd., product name: TK-16)
Hydroxypropylated phosphate cross-linked starch: HS
(Content 100% by mass, manufactured by Matsutani Chemical Industry Co., Ltd., product name: Matsuya Asagao)
・ Porous starch: OWP
(Content: 100% by mass, manufactured by Nissho Chemical Co., Ltd., product name: Long Food OWP)
・ Porous starch: Q
(Content: 100% by mass, manufactured by Nissho Chemical Co., Ltd., product name: Oil Q 50)

[Known Pitch Control Agent]
・ Nonionic surfactant: NS
(100% by mass, manufactured by Wako Pure Chemical Industries, Ltd., product name: polyoxyethylene (10) castor oil)
・ Cationic polymer: CP
(Content 20% by mass, manufactured by Wako Pure Chemical Industries, Ltd., product name: polydiallyldimethylammonium chloride)
・ Talc: Talc
(100% by mass, manufactured by Kishida Chemical Co., Ltd., product name: talc)

[Formulation Example 1]
Hydroxypropylation as a starch component while putting 726 g of pure water into a 1 L glass beaker equipped with a stirrer (manufactured by Shinto Kagaku Co., Ltd., product name: Three-One Motor, model: BL1200) and stirring at 400 rpm. 112 g starch degradation product HPS was added and held for 1 hour.
Thereafter, 162 g of highly basic aluminum chloride AA as a water-soluble aluminum compound was added and stirred for 10 minutes to obtain a pitch control agent 1 (formulation 1) having a concentration of 150 g / kg as an active ingredient.
When Formulation 1 is added so that the pitch control agent is 15.0 g / kg with respect to the mass of the absolutely dry pulp, 15 g of Formulation 1 is added as an active ingredient to the absolutely dry 150 g of pulp. At this time, the blending amount S of the starch component and the blending amount A of the water-soluble aluminum compound in the preparation 1 are 11.2 g / kg and 3.8 g / kg, respectively, as shown in Table 1, and their blending ratio S / A is 2.95.

[Formulation Examples 2 to 6]
Formulations 2 to 6 were obtained in the same manner as Formulation Example 1 except that the blending amounts of the starch component HPS and the water-soluble aluminum compound AA were changed as shown in Table 1.

[Formulation Example 7]
With a stirrer similar to Formulation Example 1, 420 g of pure water was placed in a 1 L glass beaker placed in a warm bath controlled at a temperature of 90 ° C., and 18 g of starch St as a starch component was stirred while rotating at 400 rpm. Added and held for 1 hour.
Thereafter, the temperature of the warm bath is lowered to 40 ° C. and the mixture is cooled. Then, 562 g of highly basic aluminum chloride AA as a water-soluble aluminum compound is added and stirred for 10 minutes, and a pitch with a concentration of 150 g / kg as an active ingredient is added. Control agent 7 (formulation 7) was obtained.
The blending amount S of the starch component and the blending amount A of the water-soluble aluminum compound in the preparation 7 are 1.8 g / kg and 13.2 g / kg, respectively, and the blending ratio S / A thereof is 0.14.

[Formulation Examples 8 to 10]
The compounding ratio S / A of the starch component and the water-soluble aluminum compound is fixed to 0.14, the water-soluble aluminum compound is fixed to the highly basic aluminum chloride AA, and the cationized starch CS, dextrin DS and hydroxypropyl are respectively used as the starch components. Preparations 8 to 10 were obtained in the same manner as in the above preparation examples except that the phosphorylated phosphate starch HS was used.
However, when the starch component was a degradation product such as dextrin and hydroxypropylated starch degradation product, it was not heated during the formulation process (the same applies to the following formulation examples).

[Formulation Examples 11 to 13]
The compounding ratio S / A of the starch component and the water-soluble aluminum compound is fixed to 0.14, the water-soluble aluminum compound is fixed to the polyaluminum chloride PAC, and the cationized starch CS and the hydroxypropylated starch degradation product HPS are respectively used as the starch components. Preparations 11 to 13 were obtained in the same manner as in the above preparation examples except that dextrin DS was used.

[Formulation Examples 14 and 15]
Preparations 14 and 15 are obtained in the same manner as in the above preparation examples except that hydroxypropylated starch degradation product HPS as the starch component and aluminum sulfate AS as the water-soluble aluminum compound are used in the blending ratio shown in Table 1. It was.

[Comparative Formulation Examples 1 to 12]
Comparative preparation 1 in the same manner as in the above preparation examples except that the starch component or the water-soluble aluminum compound and the known pitch control agent nonionic surfactant, cationic polymer or talc are used in the amounts shown in Table 1. ~ 12 were obtained.

[Formulation Examples 16 to 20 and Comparative Preparation Examples 13 to 18]
Preparations 16 to 20 and comparative preparations 13 to 18 were obtained in the same manner as in the above preparation examples except that the starch component and / or the water-soluble aluminum compound was used in the blending amounts shown in Table 2.

Test Example 1 [Confirmation test of pitch adhesion suppression effect]
In accordance with JAPAN TAPPI (Japan Paper Pulp Technology Association) Paper Pulp Test Method No. 11: 2000 “Pulp-Pitch Wire Mesh Adhesion Test Method”, a test for confirming the effect of inhibiting pitch adhesion was carried out.
FIG. 5 is a schematic diagram of the pulp pitch adhesion tester used in Test Example 1.
Absolutely dry 150 g softwood unbleached kraft pulp (NUKP) was disaggregated to a concentration of 3% with hot water at a temperature of 50 ° C. and placed in a 3 L glass container, and 10 g of rosin (Kishida Chemical Co., Ltd., product name: rosin) A pitch component prepared by dissolving 10 g of turpentine oil (manufactured by Kishida Chemical Co., Ltd., product name: turpentine oil) in 80 g of ethanol was added.

Next, put the glass container (diagram 2 in FIG. 5) into a constant temperature water bath (diagram 1 in FIG. 5) at a temperature of 50 ° C., assuming no pH adjustment (pH 8.5), and in a highly alkaline atmosphere. For each of cases where the pH was adjusted using an aqueous calcium hydroxide solution (pH 10), the formulations shown in Tables 1 and 2 or comparative formulations were added so as to be 15 g / kg based on the mass of the absolutely dry pulp.
However, Formulation 5 was added at 7.5 g / kg, Formulation 6 at 3.0 g / kg, Comparative Formulation 4 at 7.5 g / kg, and Comparative Formulation 12 at 160 g / kg.
Formulations 1-15 and Comparative Formulations 1-12 were tested at pH 8.5, and Formulations 16-20 and Comparative Formulations 13-18 were tested at pH 10. (Table 1 is the test result of pH 8.5 and Table 2 is 10.)
Next, twelve blades (Fig. 4 in Fig. 5) with a paper-made wire mesh attached to a ¼ circular brass frame with a radius of 70 mm are attached to the shaft (stirring bar, Fig. 3 in Fig. 5) at about 10 degrees. Was stirred for 60 minutes at a rotational speed of 200 rpm in a direction in which the pulp was pushed up by the rotation of the blades using a stirrer (made by Shinto Kagaku Co., Ltd., product name: Three-One Motor, model: BL1200) attached in a spiral shape with an inclination of .

After the stirring, the bladed shaft was taken out, washed gently in a suitable container containing water, washed off the adhering pulp, attached to a stirrer again and spun for 10 minutes to dry.
Next, the blade is removed, and the shaft and blade are washed twice with a solvent (ethanol and cyclohexane mixed in a volume ratio of 1 to 2) so that the total amount used is about 200 mL, and the attached pitch is eluted. I let you.
Next, the solvent of the pitch solution was collected in a precisely weighed container, concentrated with an evaporator, and the pitch was dried with a dryer at 105 ° C. for 1 hour.
Next, the pitch mass (100%) when the chemical was not added and the pitch mass (X%) when the chemical was added were compared, and the pitch adhesion suppression effect (adhesion inhibition rate%) was calculated.
The obtained results are shown in Tables 1 and 2 together with the blending amounts of the starch component S and the water-soluble aluminum compound A and the blending ratio S / A thereof.
In Tables 1 and 2, the numbers of Examples and Comparative Examples correspond to the numbers of Preparation Examples and Comparative Preparation Examples, respectively.

FIGS. 1 and 2 are diagrams showing the synergistic effect of preventing pitch disturbance between highly basic aluminum chloride and hydroxypropylated starch degradation products in pH 8.5 and 10 pulp slurries, respectively.
Moreover, FIG. 3 is a figure which shows the synergistic effect of pitch obstacle prevention of the aluminum sulfate and the hydroxypropylated starch decomposition product in the pulp slurry of pH 8.5.
Furthermore, FIG. 4 is a figure which shows the synergistic effect of pitch obstacle prevention of highly basic aluminum chloride and dextrin in the pulp slurry of pH 8.0.
The abscissa indicates the compounding amount of starch components (starch amount, g / kg) relative to the absolute dry pulp mass, and the ordinate indicates the inhibitory effect on the prevention of pitch disturbance (adhesion inhibition rate%). That is, the amount obtained by subtracting the starch amount from the added amount 15 g / kg of the active pharmaceutical ingredient with respect to the mass of the dry pulp becomes the blending amount (g / kg) of the water-soluble aluminum compound with respect to the mass of the dry pulp.

According to the results of Table 1 and FIG. 1, when the mixed solution has a pH of 8.5, when the starch component is 0 g / kg, that is, the water-soluble aluminum compound is 15 g / kg, the inhibitory effect is 56%, When the starch component is 15 g / kg, that is, when the water-soluble aluminum compound is 0 g / kg, the inhibitory effect is 32%. Therefore, when starch and the water-soluble aluminum compound are blended, the above two points are connected in FIG. It can be seen that the effect above the straight line, that is, a synergistic effect is exhibited, and an excellent pitch failure prevention effect is obtained.
Moreover, it turns out that the pitch obstacle prevention effect superior to the well-known pitch control agent of the comparative preparations 10-12 is acquired.

  Similarly, according to the results of Table 2 and FIG. 2, when the mixture solution has a pH of 10, when the starch component is 0 g / kg, that is, the water-soluble aluminum compound is 15 g / kg, the inhibitory effect is 53%. On the other hand, when the amount of starch is 15 g / kg, that is, when the water-soluble aluminum compound is 0 g / kg, the inhibitory effect is 0%. Therefore, when starch and a water-soluble aluminum compound are blended, a synergistic effect is exhibited. It can be seen that an excellent pitch failure prevention effect can be obtained.

  According to the results of Table 1 and FIG. 3, when the mixed solution is pH 8.5, when the hydroxypropylated starch degradation product is 0 g / kg, that is, when the aluminum sulfate is 15 g / kg, the inhibitory effect is 60%, On the other hand, when the hydroxypropylated starch degradation product is 15 g / kg, that is, when the aluminum sulfate is 0 g / kg, the inhibitory effect is 32%. Therefore, when the hydroxypropylated starch degradation product and aluminum sulfate are blended, FIG. It can be seen that an effect on the upper side of the straight line connecting the two points, that is, a synergistic effect is exhibited, and an excellent pitch failure prevention effect is obtained. In addition, since the effect by itself when the aluminum sulfate is adjusted to 7.5 g / kg in the comparative preparation 4 is low, the synergistic effect is exhibited when the aluminum sulfate and the hydroxypropylated starch degradation product are blended. Recognize.

  According to the results of Table 3 and FIG. 4 described later, when the mixed solution is pH 8.0, when dextrin is 0 g / kg, that is, high basic aluminum chloride is 15 g / kg, the inhibitory effect is 50%. On the other hand, when dextrin is 15 g / kg, that is, when high basic aluminum chloride is 0 g / kg, the inhibitory effect is 42%. Therefore, when dextrin and high basic aluminum chloride are blended, the above 2 in FIG. It can be seen that the effect on the upper side of the straight line connecting the points, that is, a synergistic effect is exhibited, and an excellent pitch failure prevention effect is obtained.

Moreover, according to the results of Tables 1 and 2, it can be seen that the same effect can be obtained even when the blending ratio of the starch component and the water-soluble aluminum compound is fixed and either one of the compounds is changed.
It can also be seen that even when the amount of the pitch control agent added as an active ingredient is 7.5 g / kg and 3 g / kg as in preparations 5 and 6, a sufficient pitch-inhibiting effect can be obtained.

[Formulation Examples 21 to 25 and Comparative Preparation Examples 19 to 24]
Formulations 21 to 25 and Comparative formulation examples 19 to 24 were obtained in the same manner as in the above formulation examples except that the starch component and / or the water-soluble aluminum compound was used in the blending amounts shown in Table 3.

Test Example 2 [Confirmation test of pitch adhesion suppression effect]
Use the aqueous solution of acrylic ester resin product (product name: PPC label, manufactured by A-One G.K.) as the pitch component, with no pH adjustment (pH 8.0), except using the preparations shown in Table 3 or comparative preparations In the same manner as in Test Example 1, a confirmation test of the effect of suppressing the adhesion of pitch was performed.
The obtained results are shown in Table 3 together with the blending amounts of the starch component S and the water-soluble aluminum compound A and the blending ratio S / A thereof.
In Table 3, the numbers of Examples and Comparative Examples correspond to the numbers of Formulation Examples and Comparative Formulation Examples, respectively.

According to the results in Table 3, organic substances derived from additives used in the manufacturing process of paper and pulp, from rosin and turpentine oils, assuming natural resins and gum substances whose pitch components are released from wood, pulp and paper Even if it replaces the water-insoluble adhesive substance mainly composed of acrylate with an acrylate ester, a synergistic effect is obtained by blending water-soluble aluminum and starch components as in the case of Test Example 1 (results of Tables 1 and 2). It can be seen that an excellent pitch suppression prevention effect is obtained.
Moreover, although the result is not shown, even when ethylene vinyl acetate is used as the pitch component, as in Test Example 2, it has been confirmed by tests that an excellent pitch suppression preventing effect can be obtained.

1 Thermostatic water tank 2 Glass container 3 Shaft 4 Blade

Claims (5)

One or more water-soluble aluminum compounds selected from polyaluminum chloride, highly basic aluminum chloride, aluminum hydroxide, hydroxyaluminum chloride, aluminum nitrate and aluminum sulfate , and starch, hydroxyalkylated starch, carboxyalkyl Formulation which is 1: 0.01-1: 3 by mass ratio with the starch component which is 1 type, or 2 or more types of starch components selected from ized starch, cationized starch, crosslinked starch, porous starch, and those decomposition products A pitch control agent for a papermaking process, which is contained as an active ingredient in a proportion. The pitch control agent for papermaking process according to claim 1, wherein the water-soluble aluminum compound is one or more selected from polyaluminum chloride, highly basic aluminum chloride and aluminum sulfate. Wherein the starch component is a starch, dextrin, hydroxypropyl starch hydrolyzate, cationic starch, according to claim 1 or 2 hydroxy alkyl phosphate-crosslinked starch and porous starch is one or more selected Pitch control agent for papermaking process. The pitch control agent for papermaking process according to any one of claims 1 to 3 , wherein the water-soluble aluminum compound is highly basic aluminum chloride, and the starch component is a hydroxypropylated starch degradation product or dextrin. The pitch control agent according to any one of claims 1 to 4 is added as an active ingredient to the pulp slurry in the papermaking process, and 0.01 to 100 g / kg of the absolutely dry pulp mass is added. A pitch obstruction prevention method characterized by preventing deterioration of product quality.

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