CN102471994B - Synthetic fiber treating agent for papermaking, method for producing synthetic fiber for papermaking, and method for producing paper-made nonwoven fabric - Google Patents

Abstract

Disclosed is a synthetic fiber treating agent for papermaking, which is capable of providing synthetic fibers for papermaking used for a paper-made nonwoven fabric with good dispersibility at low share, while suppressing the formation of air bubbles during a papermaking step. Consequently, the synthetic fiber treating agent for papermaking is capable of providing excellent fiber dispersibility. Specifically disclosed is a synthetic fiber treating agent for papermaking, which contains, as essential ingredients, a component A that is composed of a polyester compound obtained by polycondensing at least one dicarboxylic acid (derivative) selected from among aromatic dicarboxylic acids, aliphatic dicarboxylic acids having 4-22 carbon atoms and ester-forming derivatives thereof, and an alkyleneglycol, a polyalkylene glycol or a derivative thereof, and a component B that is composed of a condensation product of a fatty acid and an alkanol amine.

Description

Synthetic fiber treatment agent for papermaking, method for producing synthetic fiber for papermaking, and method for producing nonwoven fabric for papermaking

technical field

The present invention relates to a synthetic fiber treatment agent for papermaking, a method for producing a synthetic fiber for papermaking, and a method for producing a nonwoven fabric for papermaking.

Background technique

Vinylon, rayon, natural cellulose, polypropylene, and polyacrylonitrile-based fibers have been widely used as synthetic fibers for papermaking. However, in recent years, in order to improve the so-called required performance, papermaking nonwoven fabrics (sometimes simply referred to as papermaking) obtained by making paper from the following synthetic fibers for papermaking with unique softness The raw material is a hydrophobic synthetic fiber such as polyolefin fiber or polyester fiber that has hand feeling, dimensional stability, heat resistance, and low cost.

However, the current status quo is that practical products cannot fully exert the excellent performance of the hydrophobic synthetic fiber itself. Especially in the papermaking process, the current situation is that there is no papermaking that can improve the dispersibility of hydrophobic synthetic fibers required by the market, realize an increase in production speed, and have antifoaming properties and provide hydrophobicity. Synthetic fiber treatment agent for papermaking.

As a synthetic fiber treatment agent for papermaking, for example, Patent Document 1 discloses a polyester polyether block copolymer. However, in the treatment agent disclosed in Patent Document 1, the low-shear dispersibility is poor, and as a result, the uniform dispersion of the synthetic fiber bundles in the dispersion bath is insufficient. Patent Document 2 discloses a mixture containing polyethylene glycol fatty acid monoester and fatty acid soap. However, in the treatment agent disclosed in Patent Document 2, there is a large amount of foaming in the papermaking process, and the generated air bubbles adhere to the fibers. Therefore, there is a problem that the uniform dispersion in the dispersion bath is insufficient.

prior art literature

patent documents

Patent Document 1: Japanese Patent Publication No. 58-208500

Patent Document 2: Japanese Patent Laid-Open No. 2004-238764

As such, among these treating agents, the foam suppressing properties, defoaming properties, and low-shear dispersibility required for current synthetic fibers for papermaking are at insufficient levels, and high-quality nonwoven fabrics cannot be obtained. Therefore, in the nonwoven fabric produced by the papermaking method, the synthetic fiber treatment agent for papermaking is desired to have all the required properties in order to improve the quality of the nonwoven fabric.

Contents of the invention

The problem to be solved by the invention

An object of the present invention is to provide a synthetic fiber used in papermaking nonwoven fabrics that can provide good low-shear dispersibility, reduce the generation of air bubbles in the papermaking process, and provide excellent fiber dispersibility. Synthetic fiber treatment agent, method for producing synthetic fiber for papermaking, and method for producing nonwoven fabric for papermaking.

means to solve the problem

As a result of earnest research by the present inventors in order to solve the above-mentioned problems, it was found that the above-mentioned problems can be solved as long as a synthetic fiber treatment agent for papermaking containing a specific component as an essential component, and thus accomplished the present invention.

That is, the synthetic fiber treatment agent for papermaking of the present invention contains A component and B component which is a condensate of fatty acid and alkanolamine as essential components. obtained by polycondensation of at least one dicarboxylic acid (derivative), alkylene glycol, and polyalkylene glycol or derivatives thereof selected from aliphatic dicarboxylic acids and their ester-forming derivatives polyester compound.

It is preferable that the ratio of A component to the non-volatile matter of the said processing agent is 40 to 90 weight%, and the ratio of B component is 5 to 30 weight%.

The above-mentioned component A is preferably formed from an aromatic dicarboxylic acid and/or its ester-forming derivative, an alkylene glycol represented by the following chemical formula (1), and a polyalkylene glycol represented by the following chemical formula (2) or its Derivatives obtained by polycondensation of polyester compounds.

[chemical 1]

HO(R ¹ )OH (1)

(In the formula, ^R1 is an aliphatic hydrocarbon group with 2 to 8 carbons or an alicyclic hydrocarbon group with 2 to 8 carbons.)

[Chem 2]

H(OR ² ) _n OR ³ (2)

(In the formula, R ² is an alkylene group with 2 to 4 carbons, n is an integer of 20 to 200, and R ³ is a hydrogen atom, an aliphatic hydrocarbon group or an aromatic group.)

The above-mentioned B component is preferably a compound represented by the following general formula (3).

[Chem 3]

(In the formula, R ⁴ is an aliphatic hydrocarbon group with 7 to 21 carbons, R ⁵ is a hydroxyalkyl group with 1 to 4 carbons, R ⁶ is a hydrogen atom, an alkyl group with 1 to 4 carbons, or an alkyl group with 1 to 4 carbons hydroxyalkyl.)

Moreover, it is preferable that the synthetic fiber processing agent for papermaking of this invention further contains C component which is a C8-C22 fatty acid soap. Moreover, it is preferable that the ratio of A component to the non-volatile content of the said processing agent is 40-90 weight%, the ratio of B component is 5-30 weight%, and the ratio of C component is 5-30 weight%.

In addition, in the synthetic fiber treatment agent for papermaking of the present invention, it is preferable that the treatment agent is an aqueous liquid containing water, and that the proportion of non-volatile components in the entire treatment agent is 0.05 to 50% by weight.

The method for producing synthetic fibers for papermaking according to the present invention includes the step of treating raw synthetic fibers with the aforementioned synthetic fiber treating agent for papermaking.

The method for producing paper according to the present invention includes the step of dispersing the synthetic fiber for papermaking treated with the above-mentioned synthetic fiber treatment agent for papermaking in water to make paper.

The effect of the invention

The synthetic fiber treatment agent for papermaking of the present invention can improve the low-shear dispersibility of synthetic fibers for papermaking used in papermaking, reduce the generation of air bubbles in the papermaking process, and impart excellent fiber dispersibility.

According to the method for producing synthetic fibers for papermaking of the present invention, it is possible to obtain synthetic fibers for papermaking that have good dispersibility at low shear, reduce the generation of air bubbles in the papermaking process, and have excellent dispersibility.

According to the method for producing a papermaking nonwoven fabric of the present invention, a papermaking nonwoven fabric having high productivity and a uniform and good texture can be obtained.

Description of drawings

Fig. 1 is a schematic diagram of a method for measuring fiber/fiber friction when wet.

Detailed ways

The synthetic fiber processing agent for papermaking of this invention contains A component and B component as an essential component. Each component which comprises the synthetic fiber processing agent for papermaking of this invention is demonstrated below.

〔A component〕

Component A is at least one dicarboxylic acid (derivative) selected from aromatic dicarboxylic acids, aliphatic dicarboxylic acids having 4 to 22 carbon atoms, and ester-forming derivatives thereof, an alkylene glycol, and A polyester compound obtained by polycondensation of polyalkylene glycol or its derivatives. Component A has strong affinity for synthetic fibers for papermaking, low fiber/fiber friction when wet, and anti-foaming properties when dissolved in water, so it can be used together with component B to provide good dispersion. sex and antifoam.

The ester-forming derivative refers to a derivative of carboxylic acid, that is, a derivative capable of forming a hydroxyl group-containing compound and a carboxylic acid ester through esterification reaction, transesterification reaction, or the like. Specific examples of ester-forming derivatives include aromatic dicarboxylic acids, esters, acid anhydrides, and amides of aliphatic dicarboxylic acids having 4 to 22 carbon atoms.

The dicarboxylic acid (derivative) is not particularly limited, but examples include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and 2,6-naphthalene dicarboxylic acid; succinic acid, Glutaric acid, adipic acid, pimelic acid, sebacic acid and other aliphatic dicarboxylic acids with 4 to 22 carbon atoms; dimethyl terephthalate, dimethyl 5-sulfoisophthalate, 1, Aromatic dicarboxylic acid esters such as dimethyl 4-naphthalene dicarboxylate and dimethyl adipate, ester-forming derivatives of aliphatic dicarboxylic acids having 4 to 22 carbon atoms, and the like. These dicarboxylic acids (derivatives) may be used alone or in combination of two or more. Among dicarboxylic acids (derivatives), aromatic dicarboxylic acids are preferred, terephthalic acid and isophthalic acid are more preferred, and the combination of terephthalic acid and isophthalic acid is particularly preferred.

Although it does not specifically limit as an alkylene glycol, The alkylene glycol represented by the said chemical formula (1) is preferable. In the chemical formula (1), R ¹ is an aliphatic hydrocarbon group having 2 to 8 carbons or an alicyclic hydrocarbon group having 2 to 8 carbons.

Specific examples of alkylene glycol include ethylene glycol, propylene glycol, butylene glycol, butylene glycol, 1,6-hexanediol, 1,8-octanediol, 1,4- Cyclohexanediol, etc. These alkylene glycols may be used alone or in combination of two or more.

Among alkylene glycols, ethylene glycol, propylene glycol, and butanediol are preferable, and ethylene glycol is more preferable.

The polyalkylene glycol or its derivative is not particularly limited, but the polyalkylene glycol represented by the above chemical formula (2) or its derivative is preferable. The polyalkylene glycol or its derivative may consist of 1 type, and may consist of 2 or more types. Here, the polyalkylene glycol derivative refers to a compound in which a single one of the two terminal hydroxyl groups of the polyalkylene glycol molecule is blocked with an organic group.

In the chemical formula (2), R ² is an alkylene group having 2 to 4 carbon atoms. That is, the (OR ² ) moiety is an oxyalkylene group, and if the carbon number is 2, it is an oxyethylene group, if the carbon number is 3, it is an oxypropylene group, and if the carbon number is 4, it is an oxybutenyl group. These oxyalkylene groups may be used alone or in combination of two or more. The (H(OR ² ) _n O) moiety is a polyalkylene glycol moiety, but when two or more oxyalkylene groups are used in combination, the combination form may be random or block. In addition, the polyalkylene glycol moiety is preferably bonded at a ratio of oxyethylene group/oxypropylene group=100/0 to 40/60 (molar ratio), more preferably only oxyethylene group is bonded.

In the chemical formula (2), R ³ is a hydrogen atom, an aliphatic hydrocarbon group or an aromatic group.

The aliphatic hydrocarbon group may be linear or branched, saturated or unsaturated. Examples of the aliphatic hydrocarbon group include alkyl groups having 1 to 22 carbon atoms (preferably 1 to 12 carbon atoms). Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, lauryl group, stearyl group, behenyl group and the like.

The aromatic group in ^R3 of the general formula (2) refers to an organic group containing aromatic hydrocarbons such as benzene, naphthalene, and anthracene in the present invention, and the number of aromatic hydrocarbons contained may be one or more. When ^R3 is an aromatic group, the site of R bonded to the oxygen atom in the general formula (2) may or may not be an aromatic hydrocarbon part. Examples of the aromatic group include phenyl, tolyl, xylyl, styrenated phenyl, phenylethyl, distyrenated phenyl, tristyrenated phenyl, benzyl, benzylated Phenyl, dibenzylated phenyl, tribenzylated phenyl, etc.

R ³ in the general formula (2) is preferably an alkyl group or an aromatic group.

In the chemical formula (2), n is an integer of 20-200, preferably 40-150, more preferably 50-100. When n is 20, the hydrophilicity may be insufficient, it may be difficult to disperse in water, and it may be difficult to apply oil evenly to the fiber. Interfacial friction increases, and good dispersibility cannot be imparted. Here, specific examples of polyalkylene glycol derivatives include polyethylene glycol monophenyl ether (average molecular weight: 3000), polyethylene glycol (average molecular weight: 2000), polyethylene glycol monophenyl ether (average molecular weight: 3000), polyethylene glycol monophenyl ether (average molecular weight: 3000), polyethylene glycol Methyl ether (average molecular weight: 1000) and the like.

Regarding the ratio (molar ratio) of dicarboxylic acid (derivative), alkylene glycol, and polyalkylene glycol or derivatives thereof when producing the above-mentioned polyester compound as component A, it is preferable that [dicarboxylic acid (derivative) substance)/alkylene glycol] ratio (molar ratio) in the range of 20/80 to 60/40, more preferably 30/70 to 50/50, further preferably 40/60 to 50/50. By making the ratio of dicarboxylic acid (derivative) and alkylene glycol into this range, reaction will progress easily, and the unreacted thing after reaction will reduce.

In addition, the ratio (molar ratio) of [dicarboxylic acid (derivative)/polyalkylene glycol or its derivative] is preferably in the range of 100/2 to 100/100, more preferably 100/2 to 100/50 , more preferably 100/2 to 100/20. By setting the ratio of dicarboxylic acid (derivative) to polyalkylene glycol or its derivative within this range, it can be easily dispersed in water, the handling property is good, the affinity to synthetic fibers is good, and the fibers when wet /Friction between fibers is reduced and good dispersibility can be imparted.

The reaction for producing a polyester compound can be carried out by appropriately selecting methods and conditions known in this field. In addition, the reaction pressure may be carried out under normal pressure or under reduced pressure.

The ratio of A component to the nonvolatile matter of the synthetic fiber processing agent for papermaking of this invention is 40 to 90 weight%, Preferably it is 50 to 90 weight%, More preferably, it is 70 to 90 weight%. By making the ratio of A component into this range, fiber/fiber friction at the time of wetness can be reduced, and favorable dispersibility can be provided. It should be noted that the non-volatile components of the synthetic fiber treatment agent for papermaking of the present invention refer to components in the synthetic fiber treatment agent for papermaking that remain on the fiber surface even after a heat drying process for removing moisture, etc. Usually, it refers to a component that remains without volatilization under the heat treatment conditions of 110° C. and 30 minutes.

[Component B]

Component B is a condensate obtained by condensing fatty acid and alkanolamine. The fatty acid constituting the B component is a fatty acid having 8 to 22 carbon atoms, preferably a fatty acid having 12 to 22 carbon atoms, more preferably a fatty acid having 16 to 22 carbon atoms. When component B is used in combination with component A, good dispersibility and antifoaming properties can be imparted, and particularly good antifoaming properties and antifoaming properties can be imparted in a papermaking process. In addition, here, carbon number 8-22 means that the carbon number of the fatty acid which comprises B component is 8-22.

Specific examples of fatty acids constituting component B include lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, ricinoleic acid, and behenic acid. . Among these fatty acids, when the fatty acid constituting the B component is stearic acid, oleic acid, or ricinoleic acid, it is preferable that the so-called antifoaming properties, antifoaming properties, and water solubility in water are well balanced. The fatty acid which comprises B component may consist of 1 type, and may consist of 2 or more types.

Specific examples of the alkanolamine constituting the B component include monomethanolamine, dimethanolamine, monoethanolamine, diethanolamine, monopropanolamine, dipropanolamine, and monoisopropanolamine. Among these alkanolamines, diethanolamine is preferable because it is well-balanced in so-called antifoaming properties, antifoaming properties, and water solubility in water. The alkanolamine constituting the B component may be composed of one type, or may be composed of two or more types.

As B component, the fatty acid amide represented by said chemical formula (3) is mentioned, for example. In formula (3), R ⁴ is an aliphatic hydrocarbon group with 7 to 21 carbons, R ⁵ is a hydroxyalkyl group with 1 to 4 carbons, R ⁶ is a hydrogen atom, an alkyl group with 1 to 4 carbons, or an alkyl group with 1 to 4 carbons. 1 to 4 hydroxyalkyl groups.

The carbon number of R ⁴ is 7-21, preferably 11-21, particularly preferably 15-21. When the carbon number of ^R4 is less than 7, sufficient foam suppressing properties and defoaming properties are not exhibited in the papermaking process, and good dispersibility cannot be obtained in this case. On the other hand, when the carbon number of R ⁴ exceeds 21, the water solubility to water deteriorates, the workability is impaired, and the cost increases, so it is not suitable for practical use. R ⁴ may be linear or branched, saturated or unsaturated. Examples of R ⁴ include heptyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecyl, pristane, cis-9-heptadecene Base etc. Among them, as R ⁴ , undecyl, tridecyl, pentadecyl, heptadecyl and pristyl are preferable, and heptadecyl is particularly preferable.

The hydroxyalkyl group of R ⁵ may be linear or branched. The carbon number of the hydroxyalkyl group of R ⁵ is preferably 1-3, more preferably 1-2. When the number of carbon atoms in ^R5 exceeds 4, the condensation reactivity is low, and the recovery rate of the condensate becomes poor.

R ⁶ is preferably a hydroxyalkyl group having 1 to 4 carbon atoms, more preferably a hydroxyalkyl group having 1 to 2 carbon atoms. When the number of carbon atoms in ^R6 exceeds 4, the condensation reactivity becomes low, and the recovery rate of the condensate deteriorates.

When producing said B component, it is preferable that the ratio (molar ratio) of a fatty acid and an alkanolamine exists in the range of fatty acid/alkanolamine=3/1-1/3.

About the reaction of producing said B component, the method and conditions well-known in this field can be selected suitably, and it can carry out. In addition, the reaction pressure may be carried out under normal pressure or under reduced pressure.

The ratio of B component to the nonvolatile matter of the synthetic fiber processing agent for papermaking of this invention is 5 to 30 weight%, Preferably it is 5 to 25 weight%, More preferably, it is 5 to 15 weight%. By setting the proportion of component B within this range, sufficient foam suppression and defoaming properties can be imparted in the papermaking process, and fiber/fiber friction during wet can be reduced, so that good dispersibility can be imparted.

[Component C]

It is preferable that the synthetic fiber processing agent for papermaking of this invention contains C component which is C8-C22 fatty acid soap other than said A component and B component. Component C is obtained by neutralizing fatty acid with alkali. By containing component C, better dispersibility can be imparted to the synthetic fiber for papermaking with low shear.

Component C is a fatty acid soap having 8 to 22 carbon atoms, preferably a fatty acid soap having 12 to 22 carbon atoms, more preferably a fatty acid soap having 16 to 22 carbon atoms. In addition, here, a carbon number means the carbon number of the fatty acid which comprises a fatty acid soap.

Specific examples of fatty acids constituting component C include lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, ricinoleic acid, and behenic acid. . Among these fatty acids, when the fatty acid constituting component C is stearic acid, oleic acid, or ricinoleic acid, the balance between dispersibility and water solubility in water is favorable. The fatty acid which comprises C component may consist of 1 type among these fatty acids, and may consist of 2 or more types. As C component, the fatty acid soap represented by following chemical formula (4), for example is mentioned.

[chemical 4]

(R ⁷ COO ^- ) _n M ⁿ⁺ (4)

(In the above chemical formula (4), ^R7 is an aliphatic hydrocarbon group having 7 to 21 carbons, Mn ⁺ is a cation, and n is an integer of 1 or more.)

In the above chemical formula (4), examples of M ⁿ⁺ include alkali metals such as sodium, potassium, and lithium, and alkaline earth metals such as calcium and magnesium. Among them, alkali metals are preferable, and sodium and potassium are more preferable.

The carbon number of R ⁷ is 7-21, preferably 11-21, particularly preferably 15-21. When the carbon number of R ⁷ is less than 7, bubbles are generated in the papermaking process, so good dispersibility cannot be obtained. On the other hand, when the carbon number of ^R7 exceeds 21, wettability and dispersibility under low shear will deteriorate. Furthermore, since the cost increases, it is not suitable for practical use. In addition, R ⁷ may be linear or branched, saturated or unsaturated. Examples of R ⁷ include heptyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecyl, pristyl, cis-9-heptadecenyl and the like. Among them, as R ⁷ , undecyl, tridecyl, pentadecyl, heptadecyl and pristyl are preferable, and heptadecyl is particularly preferable.

When C component is contained, the ratio of C component to the non-volatile matter of the synthetic fiber processing agent for papermaking of this invention is 5-30 weight%, Preferably it is 5-25 weight%, More preferably, it is 5-15 weight%. By setting the ratio of component C within this range, favorable low-shear dispersibility can be imparted in the papermaking process.

It does not specifically limit about the manufacturing method of C component, For example, it can manufacture by neutralizing the fatty acid of C8-C22 with alkali.

[other ingredients]

The synthetic fiber treatment agent for papermaking of the present invention is preferably a water-based aqueous liquid in which the aforementioned components are dispersed or emulsified. As water used in the present invention, any of pure water, distilled water, purified water, soft water, ion-exchanged water, tap water, and the like may be used. In the case of an aqueous liquid containing water, the proportion of non-volatile components in the entire treatment agent is preferably 0.05 to 50% by weight, more preferably 0.5 to 40% by weight, and still more preferably 1 to 30% by weight.

The synthetic fiber treatment agent for papermaking of the present invention may be supplemented with additives in order to prepare an aqueous liquid in which the above-mentioned components are dispersed or emulsified, and to improve the wettability at the time of adhesion. Examples of additives used for this purpose include copolymer derivatives of polyoxyethylene and polyoxypropylene, polyoxyethylene (hereinafter abbreviated as POE) alkyl ethers, nonionic surfactants such as POE alkyl esters, alkanes, etc. Anionic surfactants such as alkyl sulfate (salt), alkyl sulfonate (salt), alkyl phosphate (salt), etc. Including the case where these additives are used in combination, an organic solvent can also be used appropriately when preparing the aqueous liquid of the treatment agent of the present invention. In addition, the proportion of these additives in the nonvolatile content of the synthetic fiber treatment agent for papermaking is not particularly limited, but is preferably less than 50% by weight, more preferably less than 20% by weight, and even more preferably less than 10% by weight.

In addition, the synthetic fiber treatment agent for papermaking of the present invention may contain antibacterial agents, antioxidants, preservatives, matting agents, pigments, antirust agents, fragrances, and the like as necessary.

The aqueous emulsion in which the non-volatile matter concentration in the synthetic fiber treatment agent for papermaking of the present invention is adjusted to 1% is an emulsion that does not generate precipitates when heated to 40°C. In addition, it is preferable not to contain an anionic surfactant and a cationic surfactant at the same time.

[Manufacturing method of synthetic fiber treatment agent for papermaking]

The synthetic fiber processing agent for papermaking of this invention can be manufactured by mixing A component and B component, and also mixing C component in some cases, and also mixing other components as needed. The order of mixing the components is not particularly limited, and these components may be mixed at room temperature (20°C to 25°C), or may be mixed after heating (20°C to 80°C).

Regarding the form of component A, there are aqueous liquid, paste, powder, block, etc., and aqueous liquid is preferable from the viewpoint of handling. The form of component B includes aqueous liquid, powder, and block, but aqueous liquid is preferable from the viewpoint of handling. The form of component C is preferably an aqueous liquid, a powder form, a lump, or the like, and an aqueous liquid is preferred from the viewpoint of handling. Therefore, the synthetic fiber treatment agent for papermaking of the present invention is preferably produced by mixing an aqueous liquid containing component A and an aqueous liquid containing component B, and optionally an aqueous liquid containing component C, and optionally other components.

The concentration of the aqueous solution containing component A is, for example, 10 to 40% by weight, the concentration of the aqueous solution containing component B is, for example, 20 to 100% by weight, and the concentration of the aqueous solution containing component C is, for example, 20 to 40%. 50% by weight.

The components constituting the synthetic fiber treatment agent for papermaking of the present invention are dissolved in water at room temperature (20 to 25° C.) or heated (20 to 80° C.) in an aqueous liquid (at least 10% by weight) / Mixed to become a homogeneous and stable latex composition. Therefore, at the production site such as applying a synthetic fiber treatment agent for papermaking to synthetic fibers, the aqueous solution of each component is dissolved/mixed at room temperature or under heating, and the synthetic fiber treatment for papermaking as a stable latex can also be prepared. agent.

In the case of handling, storing, transporting, etc., the raw materials used to manufacture the synthetic fiber treatment agent for papermaking of the present invention, the synthetic fiber treatment agent for papermaking of the present invention obtained even if A component, B component, and optionally C component coexist. The product stability of the fiber treating agent was good, so there was no problem. In this case, the aqueous liquid that is a high-concentration product of a compounded product of these components, specifically, an aqueous liquid of 50% by weight or less can be prepared. Of course, A component, B component, and C component may be separately separated without mixing.

[Manufacturing method of synthetic fibers for papermaking]

The manufacturing method of the synthetic fiber for papermaking of this invention includes the process of treating a raw material synthetic fiber with the synthetic fiber processing agent for papermaking of this invention. Here, the raw material synthetic fiber refers to a synthetic fiber that has not been treated with a synthetic fiber treatment agent for papermaking. Synthetic fibers for papermaking refer to short fibers cut to a predetermined length so that they can be used in a papermaking process. The synthetic fibers for papermaking obtained by the method for producing synthetic fibers for papermaking of the present invention are short fibers that have been treated with the synthetic fiber treatment agent for papermaking of the present invention. Dispersed, air bubbles are suppressed.

The (raw material) synthetic fibers are not particularly limited, and examples thereof include polyester fibers, polyamide fibers, polyolefin fibers, polyphenylene sulfide (PPS) fibers, polyacrylonitrile-based fibers, and polypropylene-based fibers. Composite synthetic fibers of two or more polymers, etc. Among them, when the synthetic fiber is a polyester fiber, the synthetic fiber treatment agent for papermaking of the present invention has a high affinity with the fiber, which is preferable, and polyethylene terephthalate (PET) fiber is more preferable. hour. The monofilament fineness of the fiber is preferably 0.01 to 2 dtex, and the fiber length is preferably 0.5 to 25 mm. In particular, it is particularly effective in the case of polyester-based fibers for papermaking whose fiber length is 5 mm or more and fineness is 1.0 denier or less to be cut. It should be noted that the so-called polyester fiber, in addition to polyethylene terephthalate fiber, also refers to polylactic acid (PLA) fiber, polytrimethylene terephthalate (PTT) fiber, polyethylene terephthalate Butylene glycol ester (PBT) fibers, polyethylene naphthalate (PEN) fibers, polyacrylate fibers, and the like are fibers composed of polymers obtained by condensation through reactions to form ester bonds.

The step of treating the raw material synthetic fiber with a synthetic fiber treatment agent for papermaking is not particularly limited as long as the treatment is performed before the step of making paper using the synthetic fiber for papermaking. Generally, synthetic fibers (short fibers) for papermaking can be produced through a spinning process, a stretching process, a finishing process, a crimping process, and a cutting process, but at least one selected from the spinning process, the stretching process, and the finishing process can be used. In the first process, the raw synthetic fiber is treated with a synthetic fiber treatment agent for papermaking, and it can be treated before and after the crimping process, before and after the cutting process, etc. It does not specifically limit as a processing method (oiling method), A well-known method can be employ|adopted. For example, in the case of processing in a spinning step, a stretching step, and a finishing step, it can be carried out by a common processing method (oiling method) such as a roller contact method, a spray method, and a dipping method.

It is preferable that it is 0.05-2 weight% with respect to the synthetic fiber for papermaking with respect to the adhesion amount of the non-volatile matter of the synthetic fiber processing agent for papermaking, and it is more preferable that it is 0.1-1 weight%. When the adhesion amount is less than 0.05% by weight, the dispersibility becomes insufficient, and when it exceeds 2% by weight, foaming in the dispersion tank in the papermaking process increases.

〔Manufacturing method of papermaking nonwoven fabric〕

The method for producing a nonwoven fabric for papermaking of the present invention includes a step of dispersing synthetic fibers for papermaking treated with the synthetic fiber treatment agent for papermaking of the present invention in water to make paper (also referred to as a papermaking step). This synthetic fiber for papermaking is difficult to entangle with each other during stirring/dispersion in the papermaking process, disperses into single fibers quickly, and has good stable dispersibility.

As the papermaking process, a conventional wet papermaking process can be employed. In the wet papermaking process, synthetic fibers for papermaking (short fibers) treated with a synthetic fiber treatment agent for papermaking in the above-mentioned process are charged into a paper machine, stirred/dispersed in water, and suspended. At this time, the dispersion is carried out in water with low shear, the air bubbles are suppressed, and the fibers are uniformly dispersed, thereby obtaining paper with a good texture. Next, it is supplied to a papermaking wire to make wet paper. In addition, after passing through the drying process of drying the wet paper, it is wound into a roll to obtain a wet papermaking nonwoven fabric. The papermaking wire is usually a cylinder wire or a short wire, but it can also be a fourdrinier wire, a vacuum cylinder paper machine, a hydrogenation reforming device, a connecting rod forming machine (Japanese: パ チ フ ォ マ 1) and the like. The drying step may be any one of a plurality of rotating heated rolls (multi-drum type) or a Yankee drum type.

In addition, the method for producing a nonwoven fabric for papermaking according to the present invention can produce paper by dispersing raw material synthetic fibers or synthetic fibers for papermaking in water containing the aforementioned synthetic fiber treatment agent for papermaking in the papermaking process.

According to the method for producing a papermaking nonwoven fabric of the present invention, the synthetic fibers for papermaking can be made to have good dispersibility under low shear, the occurrence of air bubbles in the papermaking process can be reduced, excellent fiber dispersibility can be imparted, and the production speed can be improved. Acceleration, not only related to cost reduction, but also to obtain uniform and good texture paper nonwovens.

The papermaking nonwoven fabric obtained by the production method of the present invention is used in various well-known fields. Especially suitable as rags, air filters, liquid filters, battery separators, base fabrics for artificial leather, disposable diapers, tea bags, and packaging materials.

Example

The present invention will be described below using examples, but the present invention is not limited thereto. In addition, the evaluation items and evaluation methods in each Example and a comparative example are as follows. Hereinafter, "%" all represent "% by weight".

The numerical values in Table 1 all represent the ratio of non-volatile components contained in the synthetic fiber treatment agent for papermaking (in component A1, component A2 and component A3, they are obtained as respective aqueous dispersions as shown below, but in the table 1 shows the ratio of each non-volatile component after removing water).

Each component described in Table 1 is as follows.

Component A1: Dimethyl terephthalate and dimethyl isophthalate are mixed at a molar ratio of 80:20 and a total of 25 parts by weight, and 20 parts by weight of ethylene glycol and polyethylene glycol monophenyl Ether (average molecular weight: 3000) 55 parts by weight, add a small amount of zinc acetate and titanium tetrabutoxide as a catalyst, make it react at 175-200°C under normal pressure for 180 minutes, distill off approximately theoretical amount of methanol, and make transesterification reaction Finish. Next, after raising the temperature to 230°C and allowing it to react for about 1 hour, the pressure was reduced to 0.5mmHg, and it was reacted at 230-260°C for 20 minutes, and then it was reacted at 275°C at 0.1-0.5mmHg for 40 minutes, and immediately The obtained polymer (average molecular weight: 7000) was thrown into warm water with stirring to obtain an aqueous dispersion of Component A1. The concentration of component A1 in the obtained aqueous dispersion was 20% by weight.

Ingredient A2: Dimethyl terephthalate, dimethyl isophthalate, and dimethyl 5-sulfoisophthalate were mixed in a molar ratio of 75:20:5 in a total of 25 parts by weight, while also mixing 10 parts by weight of ethylene glycol, 20 parts by weight of diethylene glycol and 55 parts by weight of polyethylene glycol (average molecular weight 2000), as a catalyst, add a small amount of zinc acetate and titanium tetrabutoxide to make it work under normal pressure at 175 ~ The reaction was carried out at 200° C. for 180 minutes, and an approximately theoretical amount of methanol was distilled off to complete the transesterification reaction. Next, after raising the temperature to 230°C and reacting for about 1 hour, the pressure was reduced to 0.5mmHg, and the reaction was carried out at 230-260°C for 20 minutes, and then the reaction was carried out at 275°C at 0.1-0.5mmHg for 40 minutes, and immediately The obtained polymer (average molecular weight: 5,000) was thrown into warm water with stirring to obtain an aqueous dispersion of component A2. The concentration of component A2 in the obtained aqueous dispersion was 20% by weight.

Component A3: Dimethyl terephthalate and dimethyl isophthalate were mixed at a molar ratio of 80:20 and a total of 28 parts by weight, and 7 parts by weight of ethylene glycol and polyethylene glycol monomethyl Ether (average molecular weight: 1000) 65 parts by weight, as a catalyst, add a small amount of zinc acetate and titanium tetrabutoxide, make it react for 180 minutes at 175 ~ 200 ° C under normal pressure, distill off approximately theoretical amount of methanol, make the ester The exchange reaction is complete. Next, after reacting at 230°C for about 1 hour, reduce the pressure to 0.5mmHg, and react at 230-260°C for 20 minutes, then react at 275°C at 0.1-0.5mmHg for 40 minutes, and immediately put it in warm water. The obtained polymer (average molecular weight 7000) was thrown in with stirring, and the aqueous dispersion liquid of the component A3 was obtained. The concentration of component A3 in the obtained aqueous dispersion was 20% by weight.

Ingredient B1: Condensate of lauric acid and diethanolamine

Ingredient B2: Condensate of stearic acid and diethanolamine

Ingredient B3: Condensate of myristic acid and diethanolamine

Ingredient C1: Potassium laurate

Ingredient C2: Sodium Stearate

Ingredient C3: Potassium Oleate

Ingredient C4: Sodium behenate

Component D1: POE palmitic acid monoester MW: 2500

[Table 1]

(Examples 1-16 and Comparative Examples 1-7)

(1) Preparation of latex

The components shown in Table 1 and water were mixed, and the non-volatile components accounted for 20% by weight of the synthetic fiber treatment agent for papermaking in Examples 1-16 and Comparative Examples 1-7, respectively. Synthetic fiber treatment agent for papermaking. Emulsions were prepared by diluting the obtained synthetic fiber treatment agents for papermaking with water so that the weight ratio of non-volatile components in warm water at a concentration of 25 to 60° C. was 0.4% by weight. Using the obtained latex, evaluation was performed according to (2) of the following evaluation method. The results are shown in Table 2.

(2) Fiber/fiber friction (F/F friction) test when wet

As shown in FIG. 1 , the polyester monofilament (150d/48f) (1) obtained by degreasing the fiber bundle immediately before cutting was passed through pulleys (2 to 6), and set as shown in FIG. 1 . Pull one end of the single fiber connected to the U-shaped pressure gauge (7) at a speed of 3 cm/min., thereby impregnating the single fiber with the latex in the above (1), and measure the maximum friction force between the fibers in the twisted part (g). All the atmospheres for the measurement were 20° C.×65% RH.

(3) Polyethylene terephthalate short fibers for papermaking evaluation

In the production of oiled cotton, the non-volatile content of the synthetic fiber treatment agent for papermaking used as the evaluation object was adjusted to 10 g of the raw material fiber (polyethylene terephthalate staple fiber with a fineness of 1.3 dtex and a length of 5 mm). 5 g of latex prepared in the above (1) was sprayed so that 0.2% by weight of the treated fiber was attached, and dried in a hot air dryer at 80° C. for 1 hour. For the polyethylene terephthalate short fibers (synthetic fibers for papermaking) obtained after drying, the temperature and humidity were adjusted under the evaluation environmental conditions, and then evaluated according to (4) to (7) of the following evaluation method . The results are shown in Table 2.

(4) Low shear dispersion test

500 g of ion-exchanged water was taken in a 500 ml beaker, 1.00 g of fibers for a test was added thereto, and stirred for 1 minute with a propeller stirrer (100 rpm). After the stirring was stopped, the dispersion state of the fibers after 1 minute was visually judged using the following judgment criteria, and it was used as an index of the low-shear dispersibility of the fibers.

<Judgement Criteria>

◎: Low-shear dispersibility is very good, and fibers are uniformly dispersed.

◯: Low-shear dispersibility is good, and some fiber bundles are seen.

Δ: Low-shear dispersibility is slightly better, and many fiber bundles are seen.

×: Low-shear dispersibility is poor, and many fiber bundles are seen.

(5) Foam suppression test

500 g of ion-exchanged water was taken in a 500 ml beaker, 1.00 g of fibers for the test was added thereto, and stirred for 10 minutes with a propeller stirrer (1000 rpm). The state of foaming after the stirring was stopped was visually judged using the following judgment criteria, and it was used as an index of the foam suppressing property.

<Judgement Criteria>

⊚: Very good in the state of no foaming at all.

◯: The degree of foaming is slight and almost no foaming, which is good.

△: Slightly better because foaming occurred.

×: It is a state in which foaming occurs violently, and it is remarkably unfavorable.

(6) defoaming test

500 g of ion-exchanged water was taken in a 500 ml beaker, 1.00 g of fibers for the test was added thereto, and stirred for 10 minutes with a propeller stirrer (1000 rpm). After the stirring was stopped, stir again with a propeller stirrer (100 rpm) for 1 minute. After the stirring was stopped, the condition of air bubbles adhering to the fibers was visually judged using the following judgment criteria, and it was used as an index of defoaming properties.

<Judgement Criteria>

⊚: Very good because no air bubbles adhering to the fibers were observed at all.

◯: Good condition in which almost no air bubbles adhering to the fibers were observed.

△: The state of air bubbles adhering to the fiber is partially seen, which is slightly better.

×: Air bubbles adhering to the fiber are clearly seen, and it is remarkably unfavorable.

(7) Dispersion test

500 g of ion-exchanged water was taken in a 500 ml beaker, 1.00 g of fibers for the test was added thereto, and stirred for 10 minutes with a propeller stirrer (1000 rpm). The dispersion state of the fibers after the stirring was stopped was visually judged using the following judgment criteria, and it was used as an index of dispersibility.

<Judgement Criteria>

◎: The dispersibility is very good, and the fibers are uniformly dispersed.

◯: Dispersibility is good, and some fiber bundles are seen.

Δ: The dispersibility is slightly better, and many fiber bundles are seen.

×: Dispersibility is poor, and many fiber bundles are seen.

[Table 2]

As can be seen from Table 2, compared with the synthetic fibers for papermaking using the conventional synthetic fiber treating agents for papermaking in Comparative Examples 1 to 7, the synthetic fiber treating agents for papermaking of the present invention in Examples 1 to 16 were oiled. The synthetic fiber bundle for papermaking is difficult to entangle with each other because the fiber/fiber friction is low when wet in the papermaking process when the synthetic fiber bundle is used for papermaking. In addition, since the dispersibility under low shear is good, it disperses rapidly in the single fiber. Furthermore, since the foam suppressing property and defoaming property are good, the fiber is less foamed, and since there are no air cells adhering to the fiber, the stable dispersibility is also good. By adding this synthetic fiber treatment agent for papermaking, it is possible to obtain synthetic fibers for papermaking suitable for the papermaking process in which high-quality and high-speed papermaking nonwoven fabrics are required. In addition, by using synthetic fibers for papermaking, a uniform and good papermaking nonwoven fabric can be obtained.

Industrial Utilization Possibility

The synthetic fiber treatment agent for papermaking of the present invention is suitably used for obtaining synthetic fibers for papermaking having excellent dispersibility. The method for producing synthetic fibers for papermaking according to the present invention is suitable for obtaining synthetic fibers for papermaking having excellent dispersibility. The method for producing a papermaking nonwoven fabric of the present invention is suitable for obtaining a uniform and good papermaking nonwoven fabric.

Explanation of symbols

1: Polyester monofilament

2~6: Pulley

7: U-shaped pressure gauge

8: record meter

9: Load (20g)

Claims (10)

1. A synthetic fiber treatment agent for papermaking, which contains A component and B component which is a condensate of fatty acid and alkanolamine as essential components, and said A component is selected from aromatic dicarboxylic acid, carbon number 4-22 obtained by polycondensation of at least one dicarboxylic acid or derivative thereof selected from aliphatic dicarboxylic acids and their ester-forming derivatives, alkylene glycol, and polyalkylene glycol or derivatives thereof Polyester compounds, of which, The proportion of component A in the non-volatile components of the treatment agent is 40 to 90% by weight, and the proportion of component B is 5 to 30% by weight. 2. The synthetic fiber treatment agent for papermaking according to claim 1, wherein: The A component is an aromatic dicarboxylic acid and/or its ester-forming derivative, an alkylene glycol represented by the following chemical formula (1), and a polyalkylene glycol represented by the following chemical formula (2) or its Polyester compounds obtained by polycondensation of derivatives, HO(R ¹ )OH (1) Wherein, in the formula, ^R is an aliphatic hydrocarbon group with 2 to 8 carbons or an alicyclic hydrocarbon group with 2 to 8 carbons, H(OR ² ) _n OR ³ (2) Wherein, in the formula, R ² is an alkylene group with 2 to 4 carbons, n is an integer of 20 to 200, and R ³ is a hydrogen atom, an aliphatic hydrocarbon group or an aromatic group. 3. The synthetic fiber treatment agent for papermaking according to claim 1 or 2, wherein: The B component is a compound represented by the following general formula (3),

Among them, in the formula, R ⁴ is an aliphatic hydrocarbon group with 7 to 21 carbons, R ⁵ is a hydroxyalkyl group with 1 to 4 carbons, R ⁶ is a hydrogen atom, an alkyl group with 1 to 4 carbons, or an alkyl group with 1 to 4 carbons. 4 Hydroxyalkyl. 4. The synthetic fiber treatment agent for papermaking according to claim 1 or 2, wherein: It also contains component C which is a fatty acid soap having 8 to 22 carbon atoms. 5. The synthetic fiber treatment agent for papermaking according to claim 4, wherein: The proportion of component A in the non-volatile components of the treatment agent is 40 to 90% by weight, the proportion of component B is 5 to 30% by weight, and the proportion of component C is 5 to 30% by weight. 6. The synthetic fiber treatment agent for papermaking according to claim 3, wherein: It also contains component C which is a fatty acid soap having 8 to 22 carbon atoms. 7. The synthetic fiber treatment agent for papermaking according to claim 6, wherein: The proportion of component A in the non-volatile components of the treatment agent is 40 to 90% by weight, the proportion of component B is 5 to 30% by weight, and the proportion of component C is 5 to 30% by weight. 8. The synthetic fiber treatment agent for papermaking according to claim 1 or 2, wherein: The treatment agent is an aqueous liquid containing water, and the proportion of non-volatile components in the whole treatment agent is 0.05-50% by weight. 9. A method for producing synthetic fibers for papermaking, wherein, It includes the process of treating a raw material synthetic fiber with the synthetic fiber treating agent for papermaking as described in any one of Claims 1-8. 10. A method of manufacturing a paper-making nonwoven fabric, wherein, It includes the step of dispersing the synthetic fiber for papermaking treated with the synthetic fiber treatment agent for papermaking according to any one of claims 1 to 8 in water to make paper.