JP2011021143A - Starch stain preventing agent and method for preventing starch stain - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starch stain preventing agent and a method for preventing starch stains in place of an enzyme formulated preparation, and a method for using the enzyme. <P>SOLUTION: It is found that compounds of water-soluble ureas exhibit excellent cleaning and adhesion-preventing effects on the starch stains and better cleaning and adhesion-preventing effects on the starch stains are exhibited by further combining an ethylene oxide-propylene oxide block copolymer, and/or a polyoxyethylene alkyl ether or a polyoxyethylene alkenyl ether with the compounds of water-soluble ureas. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a starch stain preventing agent and a starch stain preventing method.

  Starch stains occur on a daily basis in daily life dealing with starch-containing foods and in various industries that use starch. On the other hand, starch stain detergents or starch stain inhibitors have been proposed. However, many use compositions that combine enzymes.

  For example, Patent Document 1 discloses a starch debranching enzyme and α-amylase selected from the group consisting of pullulanase, isopulluranase and isoamylase as a cleaning composition for clothing that is effective against spilled dirt such as curry. It has been proposed to use a combination of an enzyme selected from the group consisting of β-amylase, a soap, and a surfactant other than soap. Patent Document 2 proposes a detergent composition containing a surfactant containing linear alkylbenzene sulfonate and / or alkyl sulfate, a copolymer of acrylic acid and maleic acid, and amylase. ing. Furthermore, Patent Document 3 proposes a dishwashing detergent composition containing amylase and a foaming accelerator and not containing hydrogen peroxide or a specific chelating agent. Patent Document 4 proposes a textile laundry detergent and a dishwashing detergent using a combination of a natural α-amylase and an acetonitrile derivative type bleach activating substance.

  On the other hand, among the various industries that use starch, especially in the pulp and paper industry, the ratio of wastepaper pulp has increased in recent years due to environmental considerations. Instead of a force enhancer (polyacrylamide), starch that is relatively inexpensive and has a large paper strength enhancing effect and produces a good effect on yield and fixing of a sizing agent has been used in many cases. Furthermore, in a size press apparatus in a paper manufacturing process, a chemical that exhibits a size effect such as starch is applied and sent again to a drying process to become a paper product. Starch is insoluble in cold water, but when suspended in water and heated, starch particles begin to swell at around 60 ° C., and as the temperature rises, the swollen particles disintegrate and starch molecules disperse in water Due to the nature of a highly viscous solution (so-called glue solution), excess starch that does not settle on paper becomes sticky starch stains when dried in various parts of the papermaking process, and the starch stains adhere to paper products. This is one of the causes of product quality degradation. Furthermore, starch brought in from waste paper and waste paper pulp is separated from the pulp in water and returns to the paste state, which is also a factor causing trouble in the papermaking process.

  In the press part of the papermaking process in the papermaking process, cationized starch is mainly added to the process. However, in the felt for papermaking, residual starch added, poor squeezing due to accumulation, etc. occurs. The decline in operability due to this is a problem. In the size press, oxidized starch is mainly used, but there is a problem of quality deterioration due to the starch scattered on the side surface of the roll of the press and the bearing adhering to the paper product. In addition to cationized starch and oxidized starch, starch stains, including various types of starch derived from waste paper / waste paper, form complex stains that include hydrophobic substances and inorganic substances in the process, and adhere the stains to equipment and tools. Cause trouble.

  As a method for solving these problems, Patent Document 5 proposes a paper sheet felt detergent comprising polyoxyethylene alkylphenol ether or / and polypropylene glycol / polyethylene glycol condensate, α-amylase and water. Is a composition for preventing adhesion of starch stains around a size press apparatus, comprising at least one amylolytic enzyme selected from the group consisting of α-amylase, β-amylase and glucoamylase, a preservative, and / or an inorganic salt and water. Articles and adhesion prevention methods have been proposed.

  However, in the composition combining these enzymes (enzyme formulation) and the treatment method using the enzyme, the enzyme is easily affected by temperature, so that it is also used in detergents for clothing and tableware and in the papermaking process. Even in antifouling agents, there is a drawback that sufficient effects cannot be obtained at low temperatures in winter. In addition, especially in the papermaking process, preparations containing acids and alkalis are often used to clean and remove the hydrophobic substances and inorganic substances that constitute starch dirt and hydrophobic substances and inorganic substances. Since the enzyme loses its effect in a strongly acidic or strongly alkaline pH range, it is difficult to use the enzyme-blended preparation in combination with a preparation containing these acids and alkalis. Furthermore, the activity of the enzyme tends to decrease due to the influence of a slime control agent that is generally added in the papermaking process, and the enzyme is resistant to fluctuations in the amount of starch derived from waste paper and the amount of starch added to the process. There is a drawback that it is difficult to respond quickly in the treatment method using a combination preparation or an enzyme. Therefore, there is a demand for the development and improvement of a starch stain cleaning agent, an anti-adhesion agent, and an anti-adhesion method in place of an enzyme-containing preparation and a method using an enzyme.

Japanese Patent Application Laid-Open No. 06-17279 JP 2001-64693 A Special Table 2002-536500 Special Table 2002-517553 Japanese Unexamined Patent Publication No. Sho 63-120192 JP 2006-16718 A

  An object of the present invention is to provide an enzyme compounded preparation and a starch stain preventing agent and a method for preventing starch stain in place of a method using an enzyme.

  As a result of intensive investigations on a starch stain preventing agent and a starch stain preventing method that effectively prevent soiling due to adhesion and deposition of starch, the present inventors have found that a specific water-soluble urea compound is superior to starch stains. Shows cleaning and anti-adhesion effects, and further reduces starch contamination by combining ethylene oxide-propylene oxide block copolymer and / or polyoxyethylene alkyl ether or polyoxyethylene alkenyl ether with the above water-soluble urea compounds. On the other hand, it has been found that more excellent cleaning and adhesion prevention effects are exhibited.

That is, the invention according to claim 1 is a starch antifouling agent containing (A) a water-soluble urea compound having a structure represented by the general formula [1] as an active ingredient.
(Chemical formula 1)
_{(R 1 R 2 N) (} R 3 NH) C = X ... [1]
(Wherein, X is an oxygen atom, a sulfur atom or an NH group, and R ₁ , R ₂ and R ₃ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms. , Acetyl group, NH ₂ group, or hydroxyl group.)

The invention according to claim 2 is based on (A) the water-soluble urea compound having the structure represented by the general formula [1], and (B) the general formula [2] or the general formula [3]. As an active ingredient, an ethylene oxide-propylene oxide block copolymer having a structure represented by: and / or (C) polyoxyethylene alkyl ether or polyoxyethylene alkylene ether having a structure represented by formula [4]: It is a starch stain inhibitor.
(Chemical formula 2)
_{HO- (C 2 H 4 O)} a - (C 3 H 6 O) b - (C 2 H 4 O) c H ... [2]
(However, in the formula, a + c is 16 to 80, a and c are not 0, b is 20 to 70, and (a + c) / b is 0.8 or more.)

(Chemical formula 3)
_{HO- (C 3 H 6 O)} d - (C 2 H 4 O) e - (C 3 H 6 O) f H ... [3]
(However, in the formula, d + f is 20 to 70, d and f are not 0, e is 16 to 80, and e / (d + f) is 0.8 or more.)

(Chemical formula 4)
R—O— (C ₂ H ₄ O) _g H [4]
(Wherein, R is a linear or branched alkyl group or alkenyl group having 6 to 22 carbon atoms, g is 4 to 50, and g / (the carbon number of R) is 0.6 or more. .)

  The invention according to claim 3 is the starch stain preventing agent according to claim 1 or claim 2, wherein the water-soluble urea compound of (A) is selected from urea, thiourea, guanidine, and salts thereof.

  The invention according to claim 4 is a method for preventing starch stains in a papermaking process, characterized in that (A) a water-soluble urea compound having a structure represented by the general formula [1] is added to washing water in the papermaking process. is there.

  The invention according to claim 5 includes (A) a water-soluble urea compound having a structure represented by the general formula [1], and (B) a structure represented by the general formula [2] or the general formula [3]. And / or (C) polyoxyethylene alkyl ether or polyoxyethylene alkylene ether having a structure represented by the general formula [4] is added to the washing water in the papermaking process. A method for preventing starch contamination in a papermaking process.

  By applying the starch antifouling agent and the starch antifouling method of the present invention, it is possible to wash and remove the adhered starch stains that occur daily in the daily life of dealing with starch-containing foods, and various industries that use starch, In particular, it is possible to prevent or wash starch stains adhering and depositing at various papermaking processes in the pulp and paper industry, and stains in which starch stains are combined with hydrophobic substances and inorganic substances, or to contribute to maintaining the quality of paper products.

The present invention is described in detail below.
The “water-soluble” in the water-soluble urea compound having the structure represented by the general formula [1] used in the starch stain preventing agent of the present invention is dissolved in water and water after being dissolved in a hydrophilic solvent. Means to dissolve. Examples of the water-soluble urea compounds include urea, thiourea, guanidine, guanidine nitrate, 1-ethylthiourea, 1-butylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,3-diethylthiourea, 1,1,3-trimethylthiourea, 1-aminourea (semicarbazide), 1-acetylthiourea, 1-hydroxyurea, N-hydroxythiourea, etc. are mentioned, and these compounds are produced in a state dissolved in water. Each salt can also be used in the starch stain preventing agent of the present invention. Of these, urea, thiourea, guanidine, and salts thereof are preferable.

  The starch antifouling agent of the present invention is an active ingredient (A) which dissolves a water-soluble urea compound having a structure represented by the general formula [1] in water, or dissolves in water after being dissolved in a hydrophilic solvent. Can be prepared. The content in the anti-starch antifouling agent depends on the solubility of the compound (A) used in water and a hydrophilic solvent, and can be arbitrarily selected within the range of the solubility. Include in the range. If the content is less than 1%, it is not practical to use the starch antifouling agent in a large amount when applied to starch fouling. In addition, the water used for preparation of this starch stain | pollution | contamination inhibitor can utilize a fresh water, softening water, ion-exchange water, etc.

  In the starch antifouling agent of the present invention, ethylene oxide having a structure represented by the general formula [2] or the general formula [3] is added to the water-soluble urea compound having the structure represented by the general formula [1]. -The propylene oxide block copolymer and / or the polyoxyethylene alkyl ether or polyoxyethylene alkylene ether which has a structure represented by General formula [4] can be contained.

  The ethylene oxide-propylene oxide block copolymer having the structure represented by the general formula [2] used for the starch stain preventing agent of the present invention can be obtained by addition reaction of polypropylene glycol with ethylene oxide. Examples of the ethylene oxide-propylene oxide block copolymer include Sanyo Kasei Kogyo Co., Ltd. New Pole PE series, Aoki Yushi Kogyo Co., Ltd. BLAUNON P series, Adeka Co., Ltd. Pluronic L, P, F series, or BASF Japan stock. The company's Pluronic PE series can be used.

  The ethylene oxide-propylene oxide block copolymer having the structure represented by the general formula [3] used for the starch stain preventing agent of the present invention can be obtained by addition reaction of propylene oxide to polyethylene glycol. As the ethylene oxide-propylene oxide block copolymer, for example, BLAUNON EP series of Aoki Yushi Kogyo Co., Ltd., Pluronic R series of Adeka Corporation, or Pluronic RPE series of BASF Japan Corporation can be used.

  The polyoxyethylene alkyl ether or polyoxyethylene alkylene ether having the structure represented by the general formula [4] used for the starch stain preventing agent of the present invention is obtained by adding 4 to 50 mol of ethylene oxide to the corresponding alcohol. Examples of alcohols that can be obtained by using hexanol, octyl alcohol, 2-ethylhexanol, decyl alcohol, lauryl alcohol, myristyl alcohol, stearyl alcohol, oleyl alcohol, behenyl alcohol, and coconut alcohol . As the polyoxyethylene alkyl ether or polyoxyethylene alkylene ether, for example, BLAUNON EL, CH, SR, EN, EH series, COCOSURF series, etc. manufactured by Aoki Yushi Kogyo Co., Ltd. can be used.

  Although the action of the water-soluble urea compound having the structure represented by the general formula [1] used in the starch stain preventing agent of the present invention has not been fully elucidated, hydrogen bonds in the starch molecular structure are It is thought to have the effect of loosening and peeling off the starch stain from the adhesion site. Similarly, the action of the ethylene oxide-propylene oxide block copolymer having the structure represented by (B) the general formula [2] or the general formula [3] promotes the penetration of the compound (A) into the starch soil. The action of polyoxyethylene alkyl ether or polyoxyethylene alkylene ether having a structure represented by (C) the general formula [4] wets the surface of the starch soil peeled off from the adhesion site. It is considered to have an effect of dispersing in water.

  When the starch stain preventing agent of the present invention contains the compound (A), the compound (B) and / or the compound (C), the respective ratios are (A): {(B) + (C)} by weight ratio. Is within the range of 9: 1 to 1: 9, and an optimal ratio can be selected depending on the properties of the starch stain and the state of the adhesion site. Moreover, the ratio of both in the case of containing (B) compound and (C) compound can also be suitably selected in the range of 9: 1 to 1: 9 by weight ratio. If the target starch stain is mainly starch and the purpose is to prevent adhesion or removal of the stain, the ratio of the compound (A) should be increased, and if further exfoliation effect is desired, the ratio of the compound (B) should be increased. In order to prevent small dirt particles from accumulating and becoming large adhering dirt, and to disperse starch dirt finely and efficiently discharge it from the system, the ratio of the compound (C) is increased. Is a composite soil of starch and a hydrophobic substance such as oil and fat, it is desirable to increase the ratio of the compound (B) and / or the compound (C) that can also be expected to have an emulsifying and dispersing action on the hydrophobic substance.

  The preparation method in the case of containing the (A) compound, the (B) compound and / or the (C) compound in the starch antifouling agent of the present invention comprises (A) the compound, (B) the compound and / or (C) the compound. What is necessary is just to make it melt | dissolve in water, and there is no dissolution order of each compound especially. In addition, each compound may be dissolved in water after being dissolved in a hydrophilic solvent as necessary. The content of the starch antifouling agent varies depending on the solubility of the compound (A) to (C) used in water and a hydrophilic solvent, and can be arbitrarily selected within the range of the solubility. ) To (C) The total amount of the compounds is 1 to 50% by weight. If the content is less than 1%, it is not practical to use the starch antifouling agent in a large amount when applied to starch fouling. In addition, the water used for preparation of this starch stain | pollution | contamination inhibitor can utilize a fresh water, softening water, ion-exchange water, etc.

  The starch antifouling agent of the present invention may be used in combination with other antifouling agents as long as the effect of the present invention is not impaired, and is possible within the range not impairing the effect and stability of the starch antifouling agent of the present invention. If so, another antifouling agent component may be contained in the starch antifouling agent of the present invention. Examples of such other antifouling agent components include sulfuric acid, nitric acid, hydrochloric acid, sulfamic acid, citric acid, glycolic acid, malic acid, methanesulfonic acid, maleic acid, tartaric acid, nitrilotrimethylenephosphonic acid (NTMP), hydroxy Examples include ethylidene diphosphonic acid (HEDP), ethylenediaminetetramethylene phosphonic acid (EDTP), and phosphonobutanetricarboxylic acid (PBTC).

  The starch stain preventive agent of the present invention can be used as a detergent for clothes and dishes, as well as a detergent and anti-adhesive agent for starch stains in various parts of the papermaking process, and for stains where starch stains are combined with hydrophobic substances and inorganic substances. Although it can be used as a cleaning agent or an anti-adhesive agent, especially in the press part of the papermaking process, in order to prevent the adhesion and accumulation of starch stains on the papermaking felt by the starch paper strength enhancer added to the process, In addition, in the size press, the starch stain preventing agent of the present invention can be applied to prevent adhesion and accumulation of starch stains scattered on the side surface of the press roll and the bearing.

  The method for applying the starch stain preventive agent of the present invention is not particularly limited, but in order to prevent adhesion and accumulation of starch stains in the papermaking process, the starch stain preventive agent of the present invention is added to the washing water with a chemical injection pump. Is preferred, and the washing water is sprayed on the target site. As cleaning water, fresh water or white water having a water temperature of 50 ° C. or less can be used, and the spraying method can be appropriately selected according to the situation of the target part. A method of adding a starch antifouling agent is preferred because it is easy.

  The concentration of the starch antifouling agent of the present invention added to the washing water can be appropriately selected depending on the degree of adhesion and accumulation of dirt in the papermaking process, but generally 10 to 5000 mg as an active ingredient of the starch antifouling agent. / L, and within that range, if the main purpose is to prevent adhesion, the effect may be achieved even with a small added concentration, but when the adhered starch stains are washed, a higher concentration may be required. It is customary. In addition, the active ingredient said here is the sum total of solid content of (A) compound, solid content of (B) compound, and solid content of (C) compound. When only the compound (A) is used, the solid content of the compound (A) is the amount of the active ingredient, and when using the compound (A), the compound (B) and the compound (C), the sum of the solid contents of the three is effective. It becomes the amount of ingredients.

  As a method for preventing starch stains of the present invention, in addition to the method for applying the starch stain preventive agent according to claim 1 or 2, (A) a water-soluble urea compound having a structure represented by the general formula [1] May be added to washing water alone, or (A) a water-soluble urea compound having a structure represented by the general formula [1], and (B) a general formula [2] or a general formula [3] The ethylene oxide-propylene oxide block copolymer having the structure represented and / or (C) the polyoxyethylene alkyl ether or polyoxyethylene alkylene ether having the structure represented by the general formula [4] are separately washed. It may be added to water.

  When the compound (A), the compound (B), or the compound (C) is a solid compound or a compound having a high viscosity at room temperature, dissolve or dilute in an appropriate solvent such as water, and use a chemical injection pump. Add to wash water.

  When the (A) compound, the (B) compound, and the (C) compound are separately added to the washing water, the respective addition ratios are 9 (A): {(B) + (C)} by weight ratio. : Optimal ratio can be selected depending on the nature of the starch stain and the state of the adhesion site within the range of 1-1: 9. Further, the ratio of both the (B) compound and the (C) compound can be appropriately selected within the range of 9: 1 to 1: 9 by weight. If the target starch stain is mainly starch and the purpose is to prevent adhesion or removal of the stain, the ratio of the compound (A) should be increased, and if further exfoliation effect is desired, the ratio of the compound (B) should be increased. In order to prevent small dirt particles from accumulating and becoming large adhering dirt, and to disperse starch dirt finely and efficiently discharge it from the system, the ratio of the compound (C) is increased. Is a composite soil of starch and a hydrophobic substance such as oil and fat, it is desirable to increase the ratio of the compound (B) and / or the compound (C) that can also be expected to have an emulsifying and dispersing action on the hydrophobic substance.

  (A) Addition concentration to washing water in case of single addition of compound, or addition concentration to washing water in case of combined addition of (A) compound and (B) compound and / or (C) compound, Although it can be appropriately selected depending on the degree of adhesion and accumulation of dirt in the papermaking process, in general, the total concentration of the compound (A), the compound (B), and the compound (C) is 10 to 5000 mg / In the range of L, within the range, when the main purpose is prevention of adhesion, the effect may be exerted even with a small addition concentration, but when the adhered starch soil is washed, a higher concentration is usually required. It is. In addition, the active ingredient said here is the sum total of solid content of (A) compound, solid content of (B) compound, and solid content of (C) compound. When only the compound (A) is used, the solid content of the compound (A) is the amount of the active ingredient, and when using the compound (A), the compound (B) and the compound (C), the sum of the solid contents of the three is effective. It becomes the amount of ingredients.

  Addition of the starch antifouling agent of the present invention to washing water, or addition of (A) compound, (B) compound, and (C) compound to individual washing water can be performed intermittently. However, in order to obtain a stable antifouling effect, it is more preferable to always add continuously.

  In the application to the papermaking process by the starch stain inhibitor of the present invention, (A) compound alone, or (A) compound and (B) compound and / or (C) compound in combination, There is no limitation on the use of other process additives such as an antifoaming agent, a scale control agent, etc., as long as the effects are not impaired.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these Examples.

Each component shown below was mixed and dissolved at the following blending ratio to prepare starch antifouling agents Examples 1 to 15 and Comparative Examples 1 to 3. “Ethylene oxide-propylene oxide block copolymer” is abbreviated as “EO-PO block copolymer”.
(1) Example 1
20% by weight of urea
80% by weight of water
(2) Example 2
Urea 10% by weight
EO (48 mol) -PO (35 mol) block copolymer 10% by weight
80% by weight of water
(3) Example 3
Urea 10% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 10% by weight
80% by weight of water
(4) Example 4
Urea 10% by weight
EO (48 mol) -PO (35 mol) block copolymer 5% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 5% by weight
80% by weight of water
(5) Example 5
Thiourea 10% by weight
EO (48 mol) -PO (35 mol) block copolymer 5% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 5% by weight
80% by weight of water
(6) Example 6
Guanidine 2% by weight
EO (48 mol) -PO (35 mol) block copolymer 9% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 9% by weight
80% by weight of water
(7) Example 7
Guanidine nitrate 8% by weight
EO (48 mol) -PO (35 mol) block copolymer 6% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 6% by weight
80% by weight of water
(8) Example 8
Urea 10% by weight
EO (16 mol) -PO (20 mol) block copolymer 10% by weight
80% by weight of water
(9) Example 9
Urea 10% by weight
EO (80 mol) -PO (70 mol) block copolymer 10% by weight
80% by weight of water
(10) Example 10
10% by weight of urea
Polyoxyethylene hexyl ether (EO4 mol) 10% by weight
80% by weight of water
(11) Example 11
10% by weight of urea
Polyoxyethylene-2-ethylhexyl ether (EO 30 mol)
10% by weight
80% by weight of water
(12) Example 12
10% by weight of urea
Polyoxyethylene oleyl ether (EO 50 mol) 10% by weight
80% by weight of water
(13) Example 13
10% by weight of urea
Polyoxyethylene behenyl ether (EO 20 mol) 10% by weight
80% by weight of water
(14) Example 14
18% by weight of urea
EO (48 mol) -PO (35 mol) block copolymer 1% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 1% by weight
80% by weight of water
(15) Example 15
Urea 2% by weight
EO (48 mol) -PO (35 mol) block copolymer 9% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 9% by weight
80% by weight of water
(16) Comparative Example 1
α-amylase 20% by weight
(B. subtilis, 20 units / mg, Wako Pure Chemical Industries, Ltd.)
80% by weight of water
(17) Comparative Example 2
α-amylase 10% by weight
(B. subtilis, 20 units / mg, Wako Pure Chemical Industries, Ltd.)
Adecanol B-4001 (trade name, manufactured by Adeka Corporation) 10% by weight
80% by weight of water
(18) Comparative Example 3
EO (48 mol) -PO (35 mol) block copolymer 10% by weight
Polyoxyethylene lauryl ether (EO 15 mol) 10% by weight
80% by weight of water

1. Felt adhesion starch washing test for papermaking (1)
The cleaning effect on starch adhering to papermaking felt was investigated.
(Preparation of test piece)
A 5% aqueous dispersion of eclipse Neotac # 130 (trade name, manufactured by Nippon Shokuhin Kako Co., Ltd.), which is a cationized starch, is heated to gelatinize, then cooled to room temperature, and then a new paper is made in it. A felt test piece (6 cm × 6 cm) was immersed. After 10 minutes, the test piece was taken out, washed lightly with water, and dried at 105 ° C. for 2 hours.
(Cleaning test)
100 ml of the test solutions of Examples 1 to 4 and Comparative Examples 1 and 2 diluted with water so as to contain 1000 mg / L as the total active ingredient concentration were put in a 300 ml Erlenmeyer flask and kept at a predetermined liquid temperature. The test solution was cut into 1 cm × 1 cm strips of the dried test piece prepared by the above method, and then placed in a shaker and stirred with shaking at 100 rpm for 10 minutes. After completion of stirring, the test piece was taken out of the test solution, rinsed with water, and dried at 105 ° C. for 2 hours. Moreover, the same washing | cleaning test was done using only the water of predetermined water temperature as a blank.
(Washing rate)
The starch adhering to the felt test piece before and after the washing test was extracted with hot water at 90 to 95 ° C., and the amount of starch was measured by the phenol-sulfuric acid method.
The adhesion starch washing rate was calculated by the following formula. The results are shown in Table 1.
Adhesive starch washing rate (%)
= {(Starch adhesion amount before washing test (mg))-(Starch adhesion amount after washing test (mg))} / (Starch adhesion amount before washing test (mg)) × 100
In addition, the starch adhesion amount before the washing test was about 160 mg.

  From Table 1, the adhesion starch cleaning effects of Examples 1 to 4 are higher than those of Comparative Examples 1 and 2, and the effects of Comparative Examples 1 and 2 which are enzyme-containing preparations are greatly reduced particularly in the low temperature range. It can be seen that the effect reductions of 1 to 4 are small and hardly affected by temperature.

2. Starch adhesion prevention test for papermaking felt (1)
The effect of preventing starch adhesion in papermaking felts was investigated.
(Preparation of starch gelatinization solution)
A 5% aqueous dispersion of solar eclipse Neotac # 130 (trade name, manufactured by Nippon Shokuhin Kako Co., Ltd.), which is a cationized starch, was heated to gelatinize, and then cooled to room temperature to prepare a starch gelatinized solution. .
(Adhesion prevention test)
From the papermaking process using raw materials containing waste paper and waste paper of printing paper using starch paper strength enhancer and high quality paper coated with starch sizing agent, and adding a normal slime control agent To the collected white water, 500 ml of the starch gelatinized solution prepared by the above method was added to and mixed with 4500 ml of the solution added to contain 200 mg / L of each of Examples 1 to 4 and Comparative Examples 1 and 2 as the total active ingredient concentration. A prepared test solution was prepared. Next, a new felt test piece for papermaking (circular shape with a diameter of 9 cm) was placed on the Buchner funnel, and the test liquid maintained at a liquid temperature of 30 ° C. was filtered while suctioning at a reduced pressure of 40 kilopascals. After completion of filtration, the test piece was rinsed with water and then dried at 105 ° C. for 2 hours. Moreover, the same adhesion prevention test was done using the test liquid which added and mixed 500 ml of starch gelatinization liquid prepared by said method to 4500 ml of white water extract | collected from said papermaking process as a blank.
(Starch adhesion prevention rate)
The starch adhering to the felt test piece after the test was extracted with hot water at 90 to 95 ° C., and the amount of starch was measured by the phenol-sulfuric acid method.
The starch adhesion prevention rate was calculated | required by following Formula. The results are shown in Table 2.
Starch adhesion prevention rate (%)
= {(Amount of adhered starch in blank (mg))-(Amount of adhered starch in Examples and Comparative Examples (mg))} / (Amount of adhered starch in blank (mg)) × 100

  From Table 2, the starch adhesion preventing effects of Examples 1 to 4 are higher than those of Comparative Examples 1 and 2, and the effect is white water conditions in which various agents such as a slime control agent are added and many fine fibers are suspended. It can be seen that it is high below.

3. Felt adhesion starch washing test for papermaking (2)
The same test as the “felt adhesion starch washing test for papermaking (1)” was performed except that the starch used was replaced with cationized starch and the following starch was used. However, the liquid temperature of the test liquid was 30 ° C.
Used starch (all made by Nippon Food Chemical Co., Ltd.)
Corn starch: solar eclipse corn starch (trade name)
Oxidized starch: Solar eclipse MS # 3600 (trade name)
Urea phosphate esterified starch: Solar eclipse MS # 4400 (trade name)
The results are shown in Table 3.

  From Table 3, the adhesion starch cleaning effect of Examples 1 to 4 of the present invention is higher than that of Comparative Examples 1 and 2, and even if the target starch is a starch other than cationized starch, the cleaning effect of the present invention. It can be seen that Note that starch stains attached to clothing fabrics and tableware are mainly starch of a kind called raw starch represented by corn starch, and the same effect as this test result can be expected for these stains. .

4). Starch adhesion prevention test for papermaking felt (2)
The same test as the “Starch adhesion prevention test (1) in papermaking felt” was performed except that the starch used was replaced with cationized starch and the following types of starch were used. The liquid temperature of the test liquid is 30 ° C.
Used starch (all made by Nippon Food Chemical Co., Ltd.)
Corn starch: solar eclipse corn starch (trade name)
Oxidized starch: Solar eclipse MS # 3600 (trade name)
Urea phosphate esterified starch: Solar eclipse MS # 4400 (trade name)
The results are shown in Table 4.

  From Table 4, the starch adhesion preventing effects of Examples 1 to 4 are higher than those of Comparative Examples 1 and 2, and various agents such as a slime control agent are added, and under white water conditions where a lot of fine fibers are suspended, It can be seen that the high starch adhesion-preventing effect of the present invention can be obtained even if the resulting starch is a type of starch other than cationized starch.

5. Felt adhesion starch washing test for papermaking (3)
Using Examples 5 to 15 and Comparative Example 3, the same test as “felt adhesion starch washing test for papermaking (1)” was performed. However, the liquid temperature of the test liquid was 30 ° C. The starch used is solar eclipse Neotac # 130. The results are shown in Table 5.

6). Starch adhesion prevention test for papermaking felt (3)
Using Examples 5 to 15 and Comparative Example 3, the same test as “Starch adhesion prevention test (1) in papermaking felt” was performed. The starch used is solar eclipse Neotac # 130. The results are shown in Table 5.

  From Table 5, the comparative example 3 which does not contain a specific water-soluble urea compound is clearly lower in both the adhered starch cleaning effect and the starch adhesion preventing effect than in Examples 5 to 15. A specific water-soluble urea compound exhibits excellent cleaning and anti-adhesion effects on starch stains, and further contains an ethylene oxide-propylene oxide block copolymer and / or polyoxyethylene alkyl ether or polyoxyethylene alkenyl ether. It can be seen that by combining with the above water-soluble urea compounds, the starch stains exhibit more excellent cleaning and adhesion prevention effects.

The starch stain preventing agent and the starch stain preventing method of the present invention can be used to prevent or wash starch stains that adhere to and accumulate in various papermaking processes in the pulp and paper industry. It can also be used for cleaning and removing starch stains that occur daily in the life scene.

Claims (5)

(A) A starch stain preventing agent containing a water-soluble urea compound having a structure represented by the general formula [1] as an active ingredient.
(Chemical formula 1)
_{(R 1 R 2 N) (} R 3 NH) C = X ... [1]
(Wherein, X is an oxygen atom, a sulfur atom or an NH group, and R ₁ , R ₂ and R ₃ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms. , Acetyl group, NH ₂ group, or hydroxyl group.) (A) a water-soluble urea compound having a structure represented by general formula [1], and (B) an ethylene oxide-propylene oxide block copolymer having a structure represented by general formula [2] or general formula [3]. Starch antifouling agent containing a polymer and / or (C) polyoxyethylene alkyl ether or polyoxyethylene alkylene ether having a structure represented by the general formula [4] as an active ingredient.
(Chemical formula 2)
_{HO- (C 2 H 4 O)} a - (C 3 H 6 O) b - (C 2 H 4 O) c H ... [2]
(However, in the formula, a + c is 16 to 80, a and c are not 0, b is 20 to 70, and (a + c) / b is 0.8 or more.)

(Chemical formula 3)
_{HO- (C 3 H 6 O)} d - (C 2 H 4 O) e - (C 3 H 6 O) f H ... [3]
(However, in the formula, d + f is 20 to 70, d and f are not 0, e is 16 to 80, and e / (d + f) is 0.8 or more.)

(Chemical formula 4)
R—O— (C ₂ H ₄ O) _g H [4]
(Wherein, R is a linear or branched alkyl group or alkenyl group having 6 to 22 carbon atoms, g is 4 to 50, and g / (carbon number of R) is 0.6 or more. .)   The starch stain preventing agent according to claim 1 or 2, wherein the water-soluble urea compound (A) is selected from urea, thiourea, guanidine, and salts thereof.   (A) A method for preventing starch contamination in a papermaking process, comprising adding a water-soluble urea compound having a structure represented by the general formula [1] to washing water in the papermaking process. (A) a water-soluble urea compound having a structure represented by general formula [1], and (B) an ethylene oxide-propylene oxide block copolymer having a structure represented by general formula [2] or general formula [3]. A papermaking process comprising adding a polymer and / or (C) polyoxyethylene alkyl ether or polyoxyethylene alkylene ether having a structure represented by the general formula [4] to washing water in the papermaking process Of preventing starch stains.