JP2019056050A - Cationic filler-treatment agent - Google Patents

Abstract

[Object] To provide a cationic filler treating agent capable of improving filler yield and reducing turbidity, a method for producing the same, a filler treated with the cationic filler treating agent, and a method for producing paper. The present invention relates to a cationic filler treating agent containing a copolymer of (A) epihalohydrin, (B) alkylamine, and (C) a crosslinkable monomer, and a method for producing the same. This is a method for producing filler and paper treated with the cationic filler treating agent. [Selection diagram] None

Description

  The present invention relates to a cationic filler treating agent, a method for producing the same, a filler, and a method for producing paper. In particular, the present invention relates to a cationic filler treating agent that can improve filler yield and reduce turbidity, a method for producing the same, a filler treated with the cationic filler treating agent, and a method for producing paper.

  In recent years, pulp made from recycled paper is often used due to environmental problems such as global warming and effective use of resources. As used paper, for example, newspaper paper, magazines, copy paper, corrugated cardboard, and the like, and paper that has been shredded from paper called shredder dust from offices are recently used. In general, the regenerated pulp has a lower yield because the pulp fiber length obtained in the production process is shorter than that of virgin pulp. For this reason, when manufacturing paper using recycled pulp, pitch troubles caused by pitch components derived from various types of pulp components contained in deinked waste paper pulp (hereinafter referred to as “DIP”), coat broke pulp, etc. Had occurred.

  On the other hand, in recent years, various fillers such as calcium carbonate, talc, clay, white carbon, and titanium oxide have been added in high blending amounts to improve the whiteness, opacity, printability, etc. of paper. Has been. However, when paper is produced using recycled pulp, the filler and the pitch component that did not yield because the yield of the filler is low, agglomerates and adheres to the paper machine or the paper surface, and the paper machine becomes dirty or has a paper surface defect. As a result, operability and productivity have been reduced.

  Therefore, it has been proposed to pre-treat the filler with a cationic polymer compound in advance and add it to the stock to make paper (Patent Document 1 and Patent Document 2). However, the amount of filler added tends to increase due to paper quality improvement, environmental problems, and cost reduction, and there has been a problem that the pretreatment of the filler as used so far does not provide sufficient effects. . For this reason, there has been a strong demand from the industry for a paper manufacturing method that can improve the yield of fillers and reduce the above-mentioned pitch components to reduce turbidity.

JP 57-048340 A JP 2006-118092 A

  An object of the present invention is to provide a cationic filler treating agent capable of improving filler yield and reducing turbidity, a method for producing the same, a filler treated with the cationic filler treating agent, and a method for producing paper. There is.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by using a copolymer of an epihalohydrin, an alkylamine, and a crosslinkable monomer as a filler treatment agent. The invention has been completed.

  That is, the cationic filler treating agent of the present invention is characterized by containing a copolymer of (A) an epihalohydrin, (B) an alkylamine, and (C) a crosslinkable monomer.

  In the cationic filler treating agent of the present invention, the (C) crosslinkable monomer preferably contains two or more vinyl groups in one molecule. In the cationic filler treating agent of the present invention, the (C) crosslinkable monomer is preferably methylenebisacrylamide or triallylamine.

  In the cationic filler treating agent of the present invention, the blending ratio of the (C) crosslinkable monomer in the copolymer is preferably 0.1% by mass or less.

  In the cationic filler treating agent of the present invention, the copolymer preferably has a viscosity average molecular weight in the range of 3,000 to 1,000,000.

  In the cationic filler treating agent of the present invention, the copolymer preferably has a cationic charge density of 5.0 meq / g or more.

  The method for producing a cationic filler treating agent of the present invention comprises a step of reacting the (A) epihalohydrin, the (B) alkylamine, and the (C) crosslinkable monomer.

  The filler of the present invention is characterized by being treated with the cationic filler treating agent.

  The paper manufacturing method of the present invention includes a step of preparing a filler dispersion by treating a filler with the cationic filler treatment agent, and a filler dispersion addition for adding the filler dispersion to a pulp slurry containing raw pulp Including a process.

  According to the present invention, there is provided a cationic filler treating agent that is excellent in filler yield and can reduce turbidity, a method for producing the same, a filler treated with the cationic filler treating agent, and a method for producing paper. Can do.

Hereinafter, embodiments of the present invention will be described in detail.
<Cationic filler treatment agent>
It is important that the cationic filler treating agent of the present invention contains a copolymer of (A) an epihalohydrin, (B) an alkylamine, and (C) a crosslinkable monomer.

[(A) Epihalohydrin]
Examples of the (A) epihalohydrin used in the cationic filler treating agent of the present invention include epichlorohydrin, epibromohydrin, epiiodohydrin, etc. Among them, epichlorohydrin is preferable. These may be used alone or in combination of two or more.

[(B) Alkylamine]
The (B) alkylamine used in the cationic filler treating agent of the present invention may be any of primary to tertiary alkylamines, such as methylamine, ethylamine, propylamine, butylamine, dimethylamine, diethylamine, dipropylamine. , Dibutylamine, trimethylamine, triethylamine, tripropylamine, tributylamine and the like, and primary to tertiary amines having an alkyl group having 1 to 4 carbon atoms. These may be used alone or in combination of two or more.

[(C) Crosslinkable monomer]
The crosslinkable monomer that can be used in the cationic filler treating agent of the present invention is not particularly limited, but those having two or more reactive groups, particularly vinyl groups, in one molecule are preferable. Specific examples include methylene bisacrylamide, triallylamine, diacrylamide, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, vinyloxyethyl (meth) acrylate, cyanomethyl acrylate, glyoxal, and the like. Of these, those having two or more vinyl groups in one molecule are preferable, and methylenebisacrylamide and triallylamine are particularly preferable. The term (meth) acrylate means acrylate or methacrylate.

[(A) Copolymer of Epihalohydrin, (B) Alkylamine, and (C) Crosslinkable Monomer]
In the copolymer of (A) epihalohydrin, (B) alkylamine, and (C) crosslinkable monomer, the mixing ratio of each component is not particularly limited, but the addition amount of (C) crosslinkable monomer is mass ratio. And preferably 0.1% or less. When the mixing ratio of the crosslinkable monomer exceeds 0.1%, the crosslinked structure of the polymer becomes dense, the viscosity increases, and there is a possibility of gelation. A more preferable blending ratio of the crosslinkable monomer is 0.001 to 0.01% by mass. The molar ratio of (A) epihalohydrin to (B) alkylamine is not particularly limited, but is preferably 1: 4 to 4: 1.

  The copolymer of (A) epihalohydrin, (B) alkylamine, and (C) crosslinkable monomer preferably has a lower limit of the cation charge density of 5.0 meq / g, and is 6.0 meq / g. More preferably it is. The upper limit of the cation charge density is preferably 9.0 meq / g, and more preferably 8.0 meq / g. The dispersibility of a filler can be improved more by setting it as 5.0 meq / g or more. By setting it to 9.0 meq / g or less, fixability to the filler can be further improved. The cationic charge density refers to the number of equivalents (meq / g) of cationic charge in the monomer unit constituting the copolymer. The cationic charge density refers to a numerical value determined by a colloid titration method using potassium polyvinyl sulfate (manufactured by Wako Pure Chemical Industries, Ltd., trade name “Polyvinyl Potassium Sulfate Titration Solution (N / 400)”).

  In the copolymer of (A) epihalohydrin, (B) alkylamine, and (C) crosslinkable monomer, the lower limit of the viscosity average molecular weight is preferably 3000, and more preferably 10,000. Further, the upper limit of the viscosity average molecular weight is preferably 1,000,000, more preferably 500,000, and particularly preferably 300,000. By making it 3000 or more, in addition to the fixability to a filler, the yield to the pulp at the time of adding to a pulp slurry can be improved more. By setting it to 1 million or less, the dispersibility of the filler can be further improved without aggregation of the fillers. In addition, the viscosity average molecular weight here is a viscosity average molecular weight in terms of polyvinyl alcohol measured by an intrinsic viscosity method. Specifically, the intrinsic viscosity is measured and converted using an Ubbelohde viscometer (trade name “Viscometer Ubellode” manufactured by Shibata Kagaku Co., Ltd.).

  A method for producing a copolymer of (A) epihalohydrin, (B) alkylamine, and (C) a crosslinkable monomer is not particularly limited, but a radical polymerization method is preferred. Each monomer concentration should just be 2-30 mass%, Preferably it is 5-25 weight%.

  The polymerization initiator used in the radical polymerization method is not particularly limited as long as it is water-soluble, and is usually used after being dissolved in an aqueous monomer solution. Specifically, peroxides such as hydrogen peroxide, benzoyl peroxide and tert-butyl peroxide, persulfates such as sodium persulfate, potassium persulfate and ammonium persulfate, bromine such as sodium bromate and potassium bromate And perborates such as acid salts, sodium perborate, potassium perborate, and ammonium perborate. In this case, it can be used alone, but it can also be used as a redox polymerization initiator in combination with a reducing agent. Examples of the reducing agent include low-order ionization salts such as sulfite, bisulfite, iron, copper, and cobalt, breeding amines such as N, N, N ′, and N′-tetramethylethylenediamine, and further aldose and ketose. And reducing sugars.

  Other azo compounds used as polymerization initiators include 2,2′-azobis-4-amidinopropane hydrochloride, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2, 4-Dimethylvaleronitrile, 4,4′-azobis-4-cyanovaleric acid, its salt, and the like can be used.

  Further, two or more kinds of the above polymerization initiators can be used in combination. The addition amount of a polymerization initiator is 0.01-10 mass% with respect to a monomer, Preferably it is 0.0-8 mass%. In the case of the redox system, the amount of the reducing agent added to the initiator is 0.1 to 10%, preferably 0.2 to 8% on a molar basis. The polymerization temperature is 30 to 90 ° C. in the case of a single polymerization initiator, and 5 to 50 ° C. in the case of a redox polymerization initiator. Further, it is not necessary to keep the same temperature during the polymerization, and the temperature may be appropriately changed as the polymerization progresses. Generally, the temperature is raised by the polymerization heat generated as the polymerization progresses. The atmosphere in the polymerization vessel at that time is not particularly limited, but it is better to substitute with an inert gas such as nitrogen gas in order to carry out the polymerization quickly. The polymerization time is not particularly limited, but is generally 1 to 20 hours, preferably 1 to 4 hours.

<Method for producing cationic filler treatment agent>
It is important that the method for producing a cationic filler treating agent of the present invention includes a step of reacting the (A) epihalohydrin, the (B) alkylamine, and the (C) crosslinkable monomer.

  In the manufacturing method of this invention, after obtaining the copolymer through the said reaction process, the process of dissolving the said copolymer in a solvent, for example, water, may be included. The solid concentration is preferably 20-70%. Although it does not restrict | limit especially as said melt | dissolution process, For example, it can manufacture by adding the said copolymer with respect to the water stirred with the stirrer.

<Filler>
The filler to be treated with the cationic filler treating agent of the present invention is not particularly limited. For example, titanium oxide, talc, clay, white carbon, various kaolins, calcium carbonate, magnesium carbonate, barium carbonate, aluminum hydroxide, Inorganic fillers such as calcium hydroxide, magnesium hydroxide, zinc hydroxide, zinc oxide, silicon oxide, synthetic silica, amorphous silica, acrylic resin, urea-formalin resin, polystyrene resin, phenol resin, polyethylene resin, micro hollow Examples thereof include particles. Of these, titanium oxide, talc and calcium carbonate are preferred. These may be used alone or in combination of two or more.

<Paper manufacturing method>
The paper manufacturing method of the present invention includes a step of preparing a filler dispersion by treating a filler with a cationic filler treating agent, and a step of adding a filler dispersion to a pulp slurry containing raw material pulp. It is important to include Hereinafter, each step will be described.

[Process for preparing filler dispersion]
The filler dispersion is a dispersion in which a filler is dispersed in water using a cationic filler treatment agent. The blending ratio of the filler is preferably in the range of 1.0% by mass to 50% by mass with respect to the pulp component, and more preferably in the range of 5.0% by mass to 30% by mass.

  The method for preparing the filler dispersion is not particularly limited, and for example, an aqueous slurry is prepared by first charging a powdery filler in water and uniformly dispersing it using a stirrer or the like. Thereafter, the filler dispersion can be prepared by adding the cationic filler treating agent of the present invention to the aqueous slurry and stirring for a certain time. Note that any known method may be used as the method of dispersing.

  The addition amount of the cationic filler treatment agent is preferably in the range of 0.05 to 5% by mass, more preferably in the range of 0.1 to 0.8% by mass with respect to the filler.

(Filler dispersion addition process)
In this step, the filler dispersion obtained in the preparation step is added to a pulp slurry containing raw material pulp.

  The pulp slurry is obtained by mixing and suspending raw material pulp that has been conventionally used in producing paper. As the raw material pulp, as well as virgin pulp, recycled paper recycled pulp can be used. The types of pulp include, for example, waste newspaper, magazine waste, leaflet waste paper, corrugated waste paper and shredder dust, etc. Examples thereof include chemical pulps such as pulp, soda pulp, kraft pulp, and chlorinated pulp, and mechanical and chemical pulps such as chemical pulp and chemiground pulp. In addition, examples of the raw wood of the pulp include coniferous trees such as spruce, todomatsu and red pine, and broad-leaved trees such as beech, poplar and hippopotamus. These pulps can be used in combination of two or more. It is preferable that the pulp density | concentration in a pulp slurry is 0.2-2.0 mass%.

  When adding the filler dispersion liquid to the pulp slurry, it is preferable to add the filler dispersion liquid while sufficiently stirring the pulp slurry, and examples of the place of addition include a machine chest inlet and a fan pump inlet.

  In the paper manufacturing method of the present invention, conventionally used conventional additives can be used. Examples thereof include a retention agent, a sulfuric acid band, a sizing agent, a paper strength agent, a drainage improver, a coagulant, a pitch control agent, a bulking agent, and a slime control agent. In addition, these additives may be used independently and may be used in combination of 2 or more type.

  There is no restriction | limiting in particular regarding the addition place of the said additive, For example, a mixing chest, a machine chest, a seed box, a fan pump, a screen, a white water pit etc. can be mentioned. A mixing chest and a machine chest are preferable.

  The reason why the filler yield is improved in the present invention is presumed as follows. By reacting epihalohydrin, alkylamine, and a crosslinkable monomer, a three-dimensional structure is formed in the copolymer, and the filler can be made to work in a direction to disperse the fillers due to steric hindrance, thereby further improving filler dispersibility. it can. Furthermore, since the number of reaction molecules with the filler can be increased, it is expected that the number of copolymers to be fixed to the filler is increased and the processing efficiency is increased.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely using an Example, this invention is not limited by these Examples.

<Examples 1-1 to 3-2, Comparative Examples 1-1 to 3-3, Reference Examples 1 to 3>
Various monomers and water shown in the following Tables 1 to 3 were charged into a four-round flask equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen gas introduction tube, and then adjusted to pH 4.5 with a 10% sulfuric acid aqueous solution. Thereafter, while blowing nitrogen gas, the internal temperature was raised to 45 ° C. While stirring, 10% ammonium persulfate aqueous solution and 10% sodium hydrogensulfite aqueous solution were added to initiate polymerization.
Thereafter, the temperature was kept at 85 ° C., and water was added 3 hours after the start of polymerization to complete the polymerization reaction, thereby preparing a cationic filler treatment agent. Water was added to the obtained cationic filler treating agent to make a 50% by mass solution. Using this solution, a filler dispersion and a papermaking raw material slurry were prepared by the following method. About the obtained filler dispersion liquid, papermaking raw material slurry, and the obtained paper, the yield (filler yield), turbidity, zeta potential, and filler fixing rate of the papermaking raw material slurry were evaluated. These items were evaluated by the following methods.

[Preparation of papermaking raw material slurry]
The powdery fillers listed in Tables 1 to 3 below were added in water to a concentration of 30% by mass and dispersed uniformly at 500 revolutions per minute using a stirrer to obtain an aqueous slurry. Using an aqueous solution containing 50% by mass of the neutral filler treatment agent, the cationic filler treatment agent was added to a concentration of 0.1% by mass and stirred for 5 minutes to obtain a filler dispersion.
Subsequently, a pulp-containing suspension having a pulp component concentration of 3.2% by mass was diluted with white water to prepare a pulp slurry having a slurry concentration of 1.0% by mass. White water refers to water that is recycled in the paper manufacturing process. This pulp slurry was put into a Brit type dynamic drainage jar tester (equipped with a stirrer equipped with a 40 mesh screen and turbine blades, hereinafter abbreviated as “Brit jar”), and then 1000 μm per minute using a stirrer. While stirring by rotation, after 20 seconds had elapsed, the filler dispersion was added at a filler concentration of 20% by mass with respect to the pulp components, and further stirred for 25 seconds to obtain a papermaking raw material slurry.

[Filling yield]
100 ml of the papermaking material slurry was added to Whatman No. Filtration was performed using 4 filter papers, and the obtained filtrate was dried at 110 ° C. for 60 minutes, and the filler yield (%) was measured from the ash content when the dried filter paper was heated at 550 ° C. for 2 hours.

[Turbidity]
While stirring the papermaking raw material slurry with a stirrer, 50 ml was collected from the pilot hole. Suction filtration was performed with 4 filter papers, and the formazine turbidity of the filtrate was measured according to JIS K0101. This turbidity is for evaluating the yield, the fixability of the drug and the pitch component, and the smaller the value, the higher the yield and the higher the fixing rate of the drug and the pitch component.

[Filler fixing rate]
The filler dispersion was centrifuged to separate the filler and the supernatant, and the supernatant was collected and the anion requirement A was measured by “PCD03” manufactured by MUTEK. Separately, the cationic filler treatment agent was added to water to a concentration of 0.1% by mass, and the mixture was stirred for 5 minutes at 500 rpm with a stirrer to obtain a cationic filler treatment agent dispersion. The amount B was measured by “PCD03” manufactured by MUTEK. Using the following formula, the fixing ratio (%) of the cationic filler treating agent to the filler was calculated from the anion requirement thus measured.
(1- (required anion A / required anion B)) × 100

[Zeta potential]
The zeta potential was measured by electrophoresis using a zeta potential / particle size measurement system “ELS-Z2” manufactured by Otsuka Electronics.

  From the results shown in Table 1 above, it can be seen that in the case of the cationic filler treating agents of the examples, the fixing rate is high, and the filler yield and turbidity are remarkably improved. On the other hand, Comparative Example 1-2 using the cationic filler treating agent of Comparative Example 1-1 and DADMAC (diallyldimethylammonium chloride) in which a crosslinkable monomer is not blended even if a copolymer of epihalohydrin and alkylamine is used. It can be seen that the cationic filler treating agents 1-3 and 1-3 are significantly inferior to the examples in terms of filler yield, turbidity, and fixing rate. Moreover, it can be seen from the measured value of the zeta potential that the cationic filler treating agent of the example can cationize the system more efficiently than the filler treating agent of the comparative example. Furthermore, from the results shown in Tables 2 and 3 above, even when talc or titanium oxide is used as the filler, the cationic filler treatment agent of the example is more in comparison with the cationic filler treatment agent of the comparative example than the filler yield and turbidity. It can be seen that both have improved significantly.

Claims (9)

  A cationic filler treating agent comprising a copolymer of (A) an epihalohydrin, (B) an alkylamine, and (C) a crosslinkable monomer.   The cationic filler treating agent according to claim 1, wherein the crosslinkable monomer (C) contains two or more vinyl groups in one molecule.   The cationic filler treating agent according to claim 1 or 2, wherein the (C) crosslinking monomer is methylenebisacrylamide or triallylamine.   The cationic filler treating agent according to any one of claims 1 to 3, wherein a blending ratio of the (C) crosslinkable monomer in the copolymer is 0.1% by mass or less.   The cationic filler treating agent according to any one of claims 1 to 4, wherein the copolymer has a viscosity average molecular weight of 3,000 to 1,000,000.   The cationic filler treatment agent according to any one of claims 1 to 5, wherein the copolymer has a cationic charge density of 5.0 meq / g or more. It is a manufacturing method of the cationic filler processing agent as described in any one of Claims 1-6,
The manufacturing method of the cationic filler processing agent characterized by including the process of making the said (A) epihalohydrin, the said (B) alkylamine, and the said (C) crosslinking | crosslinked monomer react.   The filler processed with the cationic filler processing agent as described in any one of Claims 1-6. A step of preparing a filler dispersion by treating the filler with the cationic filler treating agent according to any one of claims 1 to 6, and a filler for adding the filler dispersion to a pulp slurry containing raw pulp A method for producing paper, comprising a step of adding a dispersion.