JP5111770B2 - Softener composition for paper and method for producing paper using the same - Google Patents

Description

The present invention relates to a paper softener composition and a method for producing paper using the same. More specifically, the present invention relates to a paper softener composition capable of imparting excellent bending flexibility to paper and a method for producing paper using the same.

  Paper is used for various purposes in daily life, such as bookbinding paper (comic books, paperbacks, etc.), sanitary paper (toilet papers, tissue papers, etc.). In particular, sanitary paper is required to bend flexibly from its application, and many softeners for paper have been developed.

  Patent Document 1 discloses a paper softener composition comprising a di-long alkyl quaternary ammonium salt, glycerin, and water or an alcohol having 4 or less carbon atoms. Patent Document 2 discloses lanolin or a lanolin derivative. A paper softener comprising, as an active ingredient, urethane alcohol or a cationized product thereof is disclosed in Patent Document 3, and Patent Document 4 contains pyrrolidonecarboxylic acid or a salt thereof. A paper softener is disclosed, and Patent Document 5 discloses a paper softener comprising a long-chain alkyl-type quaternary ammonium salt, an unsaturated fatty acid having 8 to 24 carbon atoms, and an esterified product of fatty acid and pentaerythritol. Is disclosed. However, these softeners for paper cannot impart sufficient softness to paper.

Japanese Patent Laid-Open No. 4-100995 JP-A-53-147803 JP-A-60-139897 JP-A-7-189170 JP 7-189171 A

An object of the present invention is to provide a softener composition for paper that can impart excellent bending flexibility to paper. Another object of the present invention is to provide a method for efficiently producing paper using the softener composition for paper.

（Ｒ^１ＣＯは炭素数が１０〜２４のアシル基であり、Ｒ^２は炭素数が２〜４のアルキレン基であり、そしてＲ^３およびＲ^４はそれぞれ炭素数が１〜４のアルキル基である）。

（Ａは炭素数が４〜１２のジカルボン酸の残基であり、Ｒ ^５ 、Ｒ ^６ 、Ｒ ^９ 、およびＲ ^１０ はそれぞれ炭素数が１〜４のアルキル基であり、そしてＲ ^７ およびＲ ^８ はそれぞれ炭素数２〜４のアルキレン基である）
さらに、本発明の紙の製造方法は、パルプ１００質量部に対して、上記紙用柔軟剤組成物を、上記アミドアミン化合物（ａ）またはその塩の量が０．０３〜８質量部となるように添加する工程を包含する。 The softener composition for paper of the present invention comprises an amidoamine compound (a) represented by the following general formula (1) or a salt thereof, and a diamidediamine compound (b) represented by the following general formula (2) or The diamidediamine compound (b) or a salt thereof is in a proportion of less than 40% by mass .

(R ¹ CO is an acyl group having 10 to 24 carbon atoms, R ² is an alkylene group having 2 to 4 carbon atoms, and R ³ and R ⁴ are each an alkyl group having 1 to 4 carbon atoms. is there).

(A is a residue of a dicarboxylic acid having 4 to 12 carbon atoms, R ⁵ , R ⁶ , R ⁹ and R ¹⁰ are each an alkyl group having 1 to 4 carbon atoms, and R ⁷ and R ^8. Are each an alkylene group having 2 to 4 carbon atoms)
Moreover, process for manufacturing paper of the present invention, with respect to 100 parts by weight of pulp, the paper softeners composition, so that the amidoamine compound (a) or amount of a salt thereof is from 0.03 to 8 parts by weight The process of adding to is included.

The softener composition for paper of the present invention can impart excellent bending flexibility to paper, and can further suppress a decrease in paper tensile strength. Therefore, by using the paper softener composition of the present invention, paper having excellent bending flexibility can be obtained.

The paper softener composition of the present invention comprises the above amidoamine compound (a) or a salt thereof, and a diamidediamine compound (b) or a salt thereof (hereinafter sometimes referred to as component b). Hereinafter, each component, a paper softener composition , and a method for producing paper using the same will be described.

(Amidamine compound (a): component a)
The amidoamine compound (a) used in the present invention is represented by the following general formula (1).

Here, R ¹ CO is an acyl group having 10 to 24 carbon atoms, R ² is an alkylene group having 2 to 4 carbon atoms, and R ³ and R ⁴ are each an alkyl group having 1 to 4 carbon atoms. It is a group.

In the general formula (2), R ¹ CO is an acyl group derived from a carboxylic acid having 10 to 24 carbon atoms. Examples of such a carboxylic acid include capric acid, lauric acid, Linderic acid, myristic acid, Examples include myristoleic acid, palmitic acid, palmitoleic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, elaidic acid, arachidic acid, eicosenoic acid, behenic acid, erucic acid, lignoceric acid, and ceracolonic acid. Of these, carboxylic acids having 16 to 22 carbon atoms are preferred. These carboxylic acids may be used alone or in combination of two or more. When the number of carbon atoms is less than 10, sufficient bending flexibility cannot be imparted to the paper. When the number of carbon atoms exceeds 24, the paper is given flexibility in bending, but the resulting amidoamine compound has a high melting point, which may make handling difficult.

In the general formula (1), examples of the alkylene group having 2 to 4 carbon atoms in R ² include an ethylene group, a propylene group, and a butylene group. Among these, a propylene group is preferable.

In the general formula (1), examples of the alkyl group having 1 to 4 carbon atoms of R ³ and R ⁴ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and an isobutyl group. Of these, an ethyl group is preferred.

  The amidoamine compound (a) is obtained by reacting a dialkylaminoalkyleneamine with the carboxylic acid. This reaction is performed by a normal condensation reaction.

The amidoamine compound (a) may be used as it is as a component of a paper softener composition, or may be neutralized with an inorganic acid or an organic acid and used as a salt. The use of a salt is preferable in terms of easy handling. Examples of the acid include hydrochloric acid, sulfuric acid, carbonic acid, nitric acid, phosphoric acid, formic acid, acetic acid, propionic acid, butyric acid, glycolic acid, lactic acid, gluconic acid, salicylic acid, hydroxyvaleric acid, aspartic acid, glutamic acid, taurine, sulfamic acid and the like. Is mentioned. Among these, formic acid, acetic acid, glycolic acid, lactic acid, and gluconic acid are preferable. The amount of these acids used can be appropriately set depending on the conditions for using the paper softener composition, but the amine value of the obtained amidoamine compound (a) is measured and used so as to be equivalent to the amine value. It is preferred that

(Diamidediamine compound (b): component b)
In the present invention, the diamidediamine compound (b) is used for the purpose of further suppressing a decrease in the tensile strength of the paper. The diamidediamine compound (b) used in the present invention is represented by the following general formula (2).

Where A is a residue of a dicarboxylic acid having 4 to 12 carbon atoms, R ⁵ , R ⁶ , R ⁹ and R ¹⁰ are each an alkyl group having 1 to 4 carbon atoms, and R ⁷ and R ⁸ is an alkylene group having 2 to 4 carbon atoms.

  In the above general formula (2), A is a residue of a dicarboxylic acid having 4 to 12 carbon atoms. Examples of such a dicarboxylic acid include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, Azelaic acid, sebacic acid, dodecanedioic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, and terephthalic acid. Of these, dicarboxylic acids having 6 to 10 carbon atoms are preferred. When the number of carbon atoms exceeds 12, the paper softener using such a diamidediamine compound has a high melting point of the resulting diamidediamine compound, and may be difficult to handle.

In the general formula (2), examples of R ⁵ , R ⁶ , R ⁹ , and R ¹⁰ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and an isobutyl group. Among these, a methyl group and an ethyl group are preferable. When the number of carbon atoms exceeds 4, the softening agent for paper using such a diamidediamine compound has a high melting point of the resulting diamidediamine compound, and may be difficult to handle.

In the general formula (2), the alkylene group having a carbon number of 2 to 4 R ⁷ and R ^8, an ethylene group, a propylene group, and butylene group. Among these, an ethylene group or a propylene group is preferable.

  The diamidediamine compound (b) is obtained by reacting a dialkylaminoalkyleneamine with the dicarboxylic acid. This reaction is performed by a normal condensation reaction.

  The diamidediamine compound (b) may be used as it is, or may be used as a salt after neutralizing with an inorganic acid or an organic acid. The use of a salt is preferable in terms of easy handling. As an acid, the acid used when making the above-mentioned amidoamine compound (a) into a salt may be used. The amount of these acids used can be appropriately set depending on the conditions for using the paper softener, but the amine value of the obtained diamidediamine compound (b) is measured and used so as to be equivalent to the amine value. It is preferable.

(Softener composition for paper)
The paper softener composition of the present invention comprises the component a and the diamidediamine compound (b) or a salt thereof (component b).

In the paper softener composition of the present invention, the component b is in a proportion of less than 40% by mass. In addition to being able to impart excellent bending flexibility to the paper, the composition having the component b in such a ratio can further suppress the decrease in the tensile strength of the paper. The component b is preferably 0.1% by mass to 39.9% by mass of the composition , and more preferably 10% by mass to 35% by mass.

(Paper manufacturing method)
The paper manufacturing method of the present invention is characterized in that the paper softener composition is used in paper manufacturing. The softener composition for paper is added so that the amount of the amidoamine compound (a) or a salt thereof is 0.03 to 8 parts by mass, preferably 0.1 to 4 parts by mass with respect to 100 parts by mass of the pulp. To do. When the amount of the amidoamine compound (a) or a salt thereof is less than 0.03 parts by mass, the effect of improving the flexibility of bending may be small. When the amount of the above-mentioned amidoamine compound (a) or a salt thereof exceeds 8 parts by mass, an effect of improving flexibility corresponding to the amount used cannot be obtained, but rather the cost of paper is increased, which is economically disadvantageous.

  Examples of the pulp (raw pulp) include chemical pulp (exposed or unexposed kraft pulp of softwood or hardwood), mechanical pulp (such as ground pulp, thermomechanical pulp, chemithermomechanical pulp), deinked pulp (newspaper, magazine) Used paper). These can be used alone or in combination.

The paper softener composition of the present invention can be used in various processes in the production of paper. That is, it can be added to the papermaking system at any stage of the papermaking process (internal addition method), and can also be applied to the surface of the pulp sheet obtained by the papermaking process (external addition method). For example, the internal addition method that is added to the pulp slurry in the mixing chest, machine chest, seed box, etc. in the paper making process, or the size press, gate roll, spray, etc. that are applied to the pulp sheet surface obtained by paper making The addition method is adopted.

In particular, the internal addition method is preferably employed. For example, paper is obtained by adding the paper additive composition to a mixture (for example, pulp slurry) containing pulp and water and making paper by a usual method.

  In the paper manufacturing method of the present invention, paper machines such as a long net paper machine, a twin wire machine, and a Yankee machine, which are generally used for paper making, can be used.

  The present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

(Synthesis Example 1: Synthesis of Amidoamine Compound (a))
(Synthesis Example 1.1)
A 500 mL four-necked flask equipped with a stirrer, a condenser, a thermometer, and a nitrogen inlet tube was charged with 252.0 g (0.9 mol) of carboxylic acid (oleic acid) described in Table 1 and an amine (dimethylamino). 91.8 g (0.9 mol) of propylamine) was charged. Next, the temperature was raised to 120 to 130 ° C. with stirring in a nitrogen atmosphere, and the reaction was performed for 15 hours while removing the generated water out of the system to obtain amidoamine compound a-1 having an amine value of 149.

(Synthesis Examples 1.2 to 1.5)
Except that the carboxylic acid (0.9 mol) and amine (0.9 mol) listed in Table 1 were used, the amidoamine compounds a-2 to a-5 were respectively prepared in the same procedure as in Synthesis Example 1.1. Obtained.

(Comparative Synthesis Example 1.1)
Amidoamine compound a′-1 was obtained in the same procedure as in Synthesis Example 1.1 except that the carboxylic acid (0.9 mol) and amine (0.9 mol) shown in Table 1 were used.

(Synthesis Example 2: Synthesis of diamidediamine compound (b))
(Synthesis Example 2.1)
A 500 mL four-necked flask equipped with a stirrer, a condenser, a thermometer, and a nitrogen inlet tube was charged with 146.1 g (1 mol) of adipic acid and 260.0 g of amine (diethylaminopropylamine) listed in Table 2 ( 2 mol) was charged. Next, the temperature was raised to 120 to 130 ° C. with stirring in a nitrogen atmosphere, and the reaction was performed for 15 hours while removing the generated water out of the system to obtain a diamidediamine compound b-1 having an amine value of 299.

(Synthesis Examples 2.2 and 2.3)
Diamidediamine compounds b-2 and b-3 were obtained in the same procedure as in Synthesis Example 1.1, except that the dicarboxylic acid (1 mol) and amine (2 mol) shown in Table 2 were used.

( Reference Example 1: Preparation and evaluation of dispersion)
1. Preparation of Dispersion In a 200 mL beaker, 158.1 g of ion-exchanged water, 0.3 g of acetic acid (corresponding to 1 equivalent of the amine value of amidoamine compound a-1), and 1.6 g of amidoamine compound a-1 And stirred at 70 ° C. for 30 minutes to prepare a paper softener dispersion (referred to as Dispersion I). This dispersion I contains 1.2% by mass of the salt of amidoamine compound a-1.

2. Evaluation of Dispersion A handsheet was produced as follows using the dispersion I obtained above. And about the obtained handsheet, (1) flexibility of bending (bending rigidity) and (2) tensile strength were evaluated.

2-1. Preparation of handsheets LBKP (hardwood bleached pulp) having a freeness of 450 mL was disaggregated using a disaggregator (manufactured by Kumagaya Riken Co., Ltd.) to prepare a pulp slurry containing 1% by mass of pulp. 400 g of this pulp slurry (pulp amount 4 g) was put in a 500 mL beaker, and 2 g of the dispersion I (the amount of the salt of amidoamine compound a-1 was 0.6 parts by mass with respect to 100 parts by mass of pulp) was added. . Subsequently, it stirred for 1 minute at 250 rpm with the turbine blade of diameter 4.5cm. After stirring, 105 g of pulp slurry was used to make a paper using a TAPPI standard sheet machine (manufactured by Yasuda Seiki Co., Ltd.). After paper making, press for 5 minutes at 0.35 MPa using a hydraulic press (manufactured by Yasuda Seiki Co., Ltd.), and dry at 105 ° C. for 2 minutes using a drum dryer (manufactured by Yasuda Seiki Co., Ltd.). Three handsheets were produced. The handsheet was further stored for 17 hours in a constant temperature and humidity chamber at a temperature of 23 ° C. and a humidity of 50% to adjust the humidity.

2-2. Evaluation (1) Evaluation of bending flexibility (bending stiffness)
Using a pure bending tester (KES-FB2, manufactured by Kato Tech Co., Ltd.), the bending stiffness of the 155 mm diameter portion of the three handsheets was measured in the longitudinal direction and the transverse direction, respectively, and the average value was obtained. The average value obtained was evaluated according to the following criteria. The results are shown in Table 3.

(Evaluation criteria)
Flexural rigidity is less than 5.68 × 10 ⁻⁵ N · m ² / m: Good flexibility (◯)
Flexural rigidity of 5.68 × 10 ⁻⁵ N · m ² / m or more: Insufficient flexibility (×)

(2) Evaluation of tensile strength Three 120 × 15 mm test pieces were cut from a single handsheet, and the paper was removed using a tensile / compression tester SV-201-0-SH (manufactured by Imada Manufacturing Co., Ltd.). The tensile strength at the time of pulling apart was measured. And according to JISP8113, the tearing length was calculated from the following formula | equation, and the average of 3 sheets was calculated | required. Next, the tearing length of the handsheet when no paper softener was added (blank) was determined in the same procedure. And the ratio (ratio with a blank) of the tear length of the handsheet obtained by adding the paper softener with respect to the tear length of the handsheet in the case of the blank was evaluated on the following criteria. The results are shown in Table 3.

(Evaluation criteria)
Ratio to blank is 90% or more: Tensile strength is very good (◎)
Ratio to blank is 80% or more and less than 90%: Good tensile strength (◯)
Ratio to blank is less than 80%: tensile strength is insufficient (x)

( Reference Examples 2-5)
Using the amidoamine compound (a) and acid (corresponding to 1 equivalent to the amine value of the amidoamine compound (a)) described in Table 3, in the same procedure as in Reference Example 1, respectively, II to V were obtained. Table 3 shows the amount of the salt of the amidoamine compound (a) contained in these dispersions II to V. Subsequently, using the dispersions II to V, handsheets were produced in the same procedure as in Reference Example 1, and the obtained handsheets were evaluated. The results are shown in Table 3.

(Example 1 )
In a 200 mL beaker, 158.2 g of ion-exchanged water, 0.3 g of acetic acid (corresponding to 1 equivalent to the total amine value of amidoamine compound a-1 and diamidediamine compound b-1), 1.4 g of amidoamine Compound a-1 and 0.1 g of diamidediamine compound b-1 (mass ratio of amidoamine compound a-1 and diamidediamine compound b-1 is 90/10) were stirred at 70 ° C. for 30 minutes, and paper A dispersion of a softening agent was prepared (referred to as dispersion VI). This dispersion VI contains 1.1% by mass of the salt of amidoamine compound a-1. Subsequently, using the dispersion VI, a handsheet was produced in the same procedure as in Reference Example 1, and the obtained handsheet was evaluated. The results are shown in Table 3.

(Examples 2 and 3 )
Charge the amidoamine compound (a) and diamidediamine compound (b) at the mass ratio shown in Table 3, and add an acid (equivalent to the total amine value of the amidoamine compound (a) and diamidediamine compound (b)) Then, in the same procedure as in Reference Example 1, dispersions VII and VIII of a paper softener were obtained. Table 3 shows the amount of the salt of the amidoamine compound (a) contained in these dispersions VII and VIII. Subsequently, using the dispersion liquids VII and VIII, a handsheet was produced in the same procedure as in Reference Example 1, and the obtained handsheet was evaluated. The results are shown in Table 3.

(Comparative Example 1)
In Reference Example 1, a handsheet was produced in the same procedure as in Reference Example 1 except that the paper softener was not added, and the obtained handsheet was evaluated. The results are shown in Table 3.

(Comparative Example 2)
A handsheet was produced by the same procedure as in Reference Example 1 except that a 1% by weight ethanol solution of stearamide was used instead of the paper softener dispersion I used in Reference Example 1. The handsheets were evaluated. The results are shown in Table 3.

(Comparative Example 3)
A handsheet is produced in the same manner as in Reference Example 1 except that the paper softener dispersion IX shown in Table 3 is used instead of the paper softener dispersion I used in Reference Example 1. The handsheets obtained were evaluated. The results are shown in Table 3.

As shown in Table 3, when the paper softener dispersions I to V comprising the amidoamine compounds (a) of Reference Examples 1 to 5 were used, any of the papers (handsheets) had excellent bending flexibility. It can be seen that Furthermore, when the compositions of Examples 1 to 3 are used, it is understood that the obtained handsheets have excellent bending flexibility and lower tensile strength. .

  On the other hand, in Comparative Example 1, no paper softening agent was used, so that a paper excellent in bending flexibility could not be obtained. In Comparative Example 2, since stearic acid amide was used instead of the salt of the amidoamine compound (a), a paper excellent in bending flexibility could not be obtained. In Comparative Example 3, R1CO used a salt of an amidoamine compound having a carbon number of less than 10 (2-ethylhexanoic acid (carbon number 8)) instead of the salt of the amidoamine compound (a). An excellent paper was not obtained.

ADVANTAGE OF THE INVENTION According to this invention, the softener composition for paper which can provide the softness | flexibility of the outstanding bending is provided. When the softener composition for paper of the present invention is used, paper having excellent bending flexibility can be obtained. Paper obtained by using the paper softener of the present invention is widely used as paper in various fields such as bookbinding paper, newsprint paper, printing / information paper, cardboard base paper, paperboard, tissue paper, toilet paper, kitchen towel, etc. .

Claims (2)

It consists of an amidoamine compound (a) represented by the following general formula (1) or a salt thereof and a diamidodiamine compound (b) or a salt thereof represented by the following general formula (2). A softener composition for paper, wherein b) or a salt thereof is less than 40% by mass .

(R ¹ CO is an acyl group having 10 to 24 carbon atoms, R ² is an alkylene group having 2 to 4 carbon atoms, and R ³ and R ⁴ are each an alkyl group having 1 to 4 carbon atoms. ).

(A is a residue of a dicarboxylic acid having 4 to 12 carbon atoms, R ⁵ , R ⁶ , R ⁹ and R ¹⁰ are each an alkyl group having 1 to 4 carbon atoms, and R ⁷ and R ^8. Are each an alkylene group having 2 to 4 carbon atoms) The process includes adding the paper softener composition according to claim 1 to 100 parts by mass of pulp so that the amount of the amidoamine compound (a) or a salt thereof is 0.03 to 8 parts by mass. , Paper manufacturing method.