JP5928126B2 - Additive for paper - Google Patents

Description

  The present invention relates to a paper additive.

  Paper products other than sanitary paper and hybrid paper are industrial products that are premised on printing, and are therefore required to have high suitability for printing. Since recent printing methods are excellent in terms of efficiency, offset rotary printing is becoming mainstream. For offset rotary printing, in addition to general printability, it is particularly important that the paper layer does not easily form a blister. This phenomenon in which the paper layer becomes blister-like is called a blister, and is a phenomenon that easily occurs during offset rotary printing that uses heat during printing. The reason why blister occurs is that the internal bonding force, which is the strength inside the paper, is reduced by the force when the water inside the paper rapidly vaporizes when drying after printing, and the internal bonding of the paper layer can not withstand. is there. When blisters are generated during printing, the quality of the finished printing is greatly reduced and it is difficult to ship as printed matter.

  On the other hand, since the chemical | medical agent which improves the capacity | capacitance of paper is exhibiting the function by inhibiting the hydrogen bond between pulp fibers, inevitably reduces an internal bond strength. Since the reduction of the internal binding force causes the above-mentioned blisters and paper breaks, there is a demand for an agent that improves the paper capacity without reducing the internal binding force (paper strength) of the paper layer as much as possible.

  As an agent for improving the capacity of paper while suppressing a decrease in paper strength, a partially substituted esterified product of a polyhydric alcohol and a fatty acid mixture containing a fatty acid having a specific carbon number having two or more unsaturated bonds in a predetermined ratio A mixture (Patent Document 1), a reaction product of an amide compound obtained by reaction of polyalkylene polyamines and monocarboxylic acids with an epihalohydrin, an emulsifier having an alkyl group and / or an alkenyl group having 4 to 20 carbon atoms, and Examples thereof include a softening agent for paper containing water and a predetermined mass ratio (Patent Document 2). However, there has not yet been obtained a drug that achieves both good paper capacity improvement and suppression of paper strength reduction.

JP 2007-177072 A JP 2010-144271 A

  In view of the above circumstances, an object of the present invention is to provide a paper additive that achieves both good paper capacity improvement and suppression of paper strength reduction.

  As a result of intensive studies to solve the above problems, the inventors of the present invention contain a specific polyoxypropylene polyamine (A) and a specific amidoamine compound (B) at a specific mass ratio, and a specific total amine It has been found that a paper additive having a valence achieves the above object.

  That is, the paper additive of the present invention is an aliphatic having 12 to 24 carbon atoms with respect to 1 mol of the polyoxypropylene polyamine (A) represented by the formula (1) and 1 mol of the polyamine represented by the formula (2). It contains an amidoamine compound (B) obtained by condensing 1 to 5 mol of monocarboxylic acid, and the mass ratio (A / B) of polyoxypropylene polyamine (A) to amidoamine compound (B) is 1/99 to 30/70, and the total amine value is 60 to 230 mgKOH / g.

(In the formula, Z is a dehydroxylated residue of a divalent or trivalent alcohol, OP is an oxypropylene group, a is an average added mole number of the oxypropylene group, and b is 2 or 3. .)

(In the formula, c is an integer of 2 to 5.)

  According to the paper additive of the present invention, it is possible to achieve both good paper capacity improvement and suppression of paper strength reduction.

  Hereinafter, embodiments of the present invention will be described. The paper additive of the present invention contains a specific polyoxypropylene polyamine (A) and a specific amidoamine compound (B) in a specific mass ratio and has a specific total amine value. Hereinafter, the polyoxypropylene polyamine (A) and the amidoamine compound (B) will be described.

[Polyoxypropylene polyamine (A)]
The polyoxypropylene polyamine (A) used in the present invention is a compound represented by the above formula (1), and an oxypropylene group having an amino group in the dehydroxylation residue (Z) of a divalent or trivalent alcohol. An added aliphatic ether amine compound. Examples of the divalent or trivalent alcohol include divalent alcohols such as ethylene glycol, propylene glycol, and butylene glycol, and trivalent alcohols such as glycerin and trimethylolpropane, preferably propylene glycol and glycerin, and more preferably Is propylene glycol.

  OP in the formula (1) is an oxypropylene group. The average addition mole number a of oxypropylene is 1-40, Preferably it is 1-35, More preferably, it is 1-10. The oxypropylene group interacts with hydrogen in the cellulose molecule and is considered advantageous for fixing to the pulp fiber. However, when the average added mole number a increases, the hydrophobicity becomes too high, and the effect on the pulp fiber. It is difficult to fix the target. That is, when the average added mole number a of the oxypropylene group is out of the above range, there is a possibility that the paper strength reduction cannot be sufficiently suppressed.

  B in the formula (1) is the number of amino groups, which is the same as the number of dehydroxylated groups in Z. Since alcohol is divalent or trivalent, b is 2 or 3, preferably 2.

  The total amine value of the polyoxypropylene polyamine (A) used in the present invention can be adjusted by changing the average addition mole number a of oxypropylene and the amino group number b. For example, the amine value can be increased by using polyoxypropylene polyamine (A) having a small average added mole number a and a large amino group number b. In the present invention, two or more polyoxypropylene polyamines (A) having different hydroxyl group residues (Z), average added mole number a, and amino group number b in formula (1) may be used.

  Commercially available products of polyoxypropylene diamine, which is an example of polyoxypropylene polyamine (A), include Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine T-403, Jeffamine by Huntsman. Examples thereof include T-3000 and Jeffamine T-5000.

[Amidamine compound (B)]
The amidoamine compound (B) used in the present invention is an amidoamine compound obtained by condensing 1 to 5 mol of an aliphatic monocarboxylic acid having 12 to 24 carbon atoms to 1 mol of the polyamine represented by the above formula (2). It is.

(Polyamine)
The polyamine represented by the formula (2) is an aliphatic polyamine having a primary amino group at the terminal and having a secondary amino group bonded linearly with an ethylene chain. In this polyamine, all amino groups can be condensed with carboxyl groups. In formula (2), c is an integer of 2-5, and 2 is preferable. Since each polyamine has a specific boiling point, it can be separated by a distillation operation. In this invention, the 1 type (s) or 2 or more types of polyamine represented by Formula (2) can be used.

(Aliphatic monocarboxylic acid)
In order to condense with the amine, an aliphatic monocarboxylic acid is used in the present invention. The aliphatic monocarboxylic acid used in the present invention is a fatty acid having 12 to 24 carbon atoms. Specific examples include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, arachidic acid, behenic acid, erucic acid, and lignoceric acid. Of these, fatty acids having 14 to 20 carbon atoms are preferred. These aliphatic monocarboxylic acids may be used alone or as a mixture.

  When the number of carbon atoms of the aliphatic monocarboxylic acid is less than 12, it is considered that the ability to improve the paper capacity is reduced, and fixing to the pulp is lowered due to the improvement in hydrophilicity. On the other hand, when the number of carbon atoms of the aliphatic monocarboxylic acid exceeds 24, the aggregation of agents derived from the cohesive energy of the alkyl chain easily occurs, resulting in water-insoluble aggregates, and fixing to pulp fibers in the papermaking process. Is expected to decrease.

  The amidoamine compound (B) used in the present invention is obtained by subjecting 1 mol of the aliphatic monocarboxylic acid to a condensation reaction with 1 mol of the polyamine. For example, polyamine and aliphatic monocarboxylic acid are mixed without solvent, and the temperature is raised to 160 to 230 ° C. while stirring in an inert gas atmosphere such as nitrogen gas, and the produced water produced as a by-product with the reaction is moved out of the reaction system. It can manufacture by making it react, removing. If the number of moles of the aliphatic monocarboxylic acid to be condensed with respect to 1 mole of polyamine is smaller than 1, it is considered that the ability to improve the paper capacity is reduced and the fixing to the pulp is lowered due to the improved hydrophilicity. On the other hand, when the number of moles of the aliphatic monocarboxylic acid to be condensed with respect to 1 mol of polyamine is larger than 5, the aggregation of agents derived from the cohesive energy of the alkyl chain easily occurs to form a water-insoluble aggregate. It is thought that the fixing to the pulp fiber at the time decreases. In addition, the number of moles of the aliphatic monocarboxylic acid to be reacted with 1 mole of the polyamine compound is hereinafter also referred to as “reaction molar ratio”.

  The total amine value of the amidoamine compound (B) used in the present invention is adjusted by changing the number of amino groups per mole of the polyamine, the reaction molar ratio of the aliphatic carboxylic acid, and the carbon number of the aliphatic monocarboxylic acid. be able to. For example, the total amine value can be increased by using a polyamine having a large number of amino groups per mole, reducing the reaction molar ratio, or using an aliphatic monocarboxylic acid having a small number of carbon atoms.

[Additives for paper]
The paper additive of the present invention has a mass ratio (A / B) of polyoxypropylene polyamine (A) to amidoamine compound (B) of 1/99 to 30/70, preferably 5/95 to 15/85. Composed.

  The total amine value of the paper additive is 60 to 230 mgKOH / g, preferably 100 to 180 mgKOH / g. The above range of the total amine value indicates that the paper additive has appropriate hydrophobicity in order to achieve a good effect. That is, a compound having a high effect of improving the paper capacity has an important balance between the hydrophobicity that can be fixed to the pulp fiber and the hydrophilicity that can be uniformly dispersed in the papermaking process. When the total amine value is less than 60 mgKOH / g, the hydrophobicity is too high and the chemicals are likely to aggregate to form water-insoluble aggregates, which may reduce the fixing to pulp fibers in the papermaking process. On the other hand, when the total amine value exceeds 230 mgKOH / g, the hydrophilicity is too high, so that it is difficult to fix to the pulp fiber, and the fixing to the pulp fiber may be insufficient in the paper making process. For the above reasons, when the total amine value range specified is exceeded, there is a possibility that a sufficient paper capacity improving effect cannot be obtained.

  The total amine value can be measured according to a known method, for example, Tf 1b-64 (indicator method) of American Oil Chemists' Society (AOCS). Further, the adjustment of the total amine value of the paper additive can be carried out by appropriately adjusting the total amine value and the mass ratio (A / B) of the polyoxypropylene polyamine (A) and amidoamine compound (B) to be used. it can.

  The paper additive of the present invention can typically be used as a dispersion by dispersing the above mixture in a dispersion medium. As the dispersion medium, water is preferable. In order to improve dispersibility, alcohols such as ethanol, propylene glycol, and glycerin may be blended. When the paper additive of the present invention is used as a dispersion, it is preferably neutralized with an acid to form a salt in order to facilitate the preparation of the dispersion. Examples of the acid used in this case include various inorganic acids or organic acids. Specifically, hydrochloric acid, sulfuric acid, carbonic acid, nitric acid, phosphoric acid, formic acid, acetic acid, propionic acid, butyric acid, glycolic acid, lactic acid, Examples include gluconic acid, salicylic acid, hydroxyvaleric acid, aspartic acid, glutamic acid, taurine, sulfamic acid, and the like. Preferred are formic acid and acetic acid. The amount of these acids to be used can be appropriately set depending on the conditions for using the paper additive, but an amount corresponding to 1 equivalent with respect to the total amine value of the paper additive is preferable.

  The paper additive of the present invention can achieve a good increase in paper capacity and suppress a reduction in paper strength that accompanies it, so bookbinding paper, newsprint, printing / information paper, cardboard paper, paperboard, tissue paper It can be widely used for various papers such as toilet paper and kitchen towels. In particular, since it is possible to suppress the occurrence of blisters that are likely to occur during offset rotary printing, it can be suitably used for paper for offset rotary printing.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.

[Synthesis of Amidoamine Compound (B)]
Polyamines (1 to 3) listed in Tables 1 and 2 and aliphatic monocarboxylic acids listed in Table 2 are subjected to a condensation reaction at the reaction molar ratios listed in Table 2 (Synthesis Examples 1 to 3 and Comparative Synthesis Examples 1 to 2). , Amidoamine compounds (B-1 to B-3, B′-1 to B′-2) were obtained. Note that c in Table 1 represents c in the formula (2).

[Measurement of total amine value]
For each of the amidoamine compounds (B-1 to B-3, B′-1 to B′-2) described in Table 2, the total amine value was measured according to AOCS Tf 1b-64 (indicator method). Described.

[Examples 1 to 5 and Comparative Examples 2 to 6]
The polyoxypropylene polyamines (A-1, A-2) listed in Table 3 and the amidoamine compounds (B-1 to B-3, B′-1 to B′-2) listed in Table 2 were used at the ratios listed in Table 4. The paper additive was obtained by mixing. Moreover, the paper additive of the amide amine compound which does not contain polyoxypropylene polyamine and the paper additive containing hexamethylenediamine instead of polyoxypropylene polyamine were also obtained. The total amine value of the resulting paper additive was measured according to AOCS Tf 1b-64 (indicator method) and listed in Table 4. In Table 3, Z, a, and b represent Z, a, and bc, respectively, in Formula (1).

  Dispersions of paper additives (1 to 10) were prepared in the following manner, and were sequentially designated as Examples 1 to 5 and Comparative Examples 2 to 6. The dispersion was prepared by adding an amount of acetic acid corresponding to 1 equivalent to the total amine value of each paper additive to ion-exchanged water, and dispersing it to 1.0 mass% as an acetate salt.

[Evaluation of paper additives]
Handsheets (Examples 1 to 5 and Comparative Examples 2 to 6) were prepared as follows using the paper additive dispersions (1 to 10) obtained above. The handsheet of Comparative Example 1 is a sheet prepared by the same procedure as Example 1 except that the paper additive was not added. The obtained handsheets were evaluated for paper capacity and internal bond strength (paper strength).

(1) Preparation of handsheet A pulp slurry containing 1% by mass of LBKP (hardwood bleached pulp) having a freeness of 420 mL was prepared. 400 g (4 g of pulp amount) of this pulp slurry was taken in a beaker, 0.5% by mass of the above dispersion was added as an effective component, and the mixture was stirred for 1 minute with a turbine blade. After that, paper is made with a TAPPI standard sheet machine (manufactured by Yasuda Seiki Seisakusho Co., Ltd.), pressed with a hydraulic press machine (manufactured by Yasuda Seiki Seisakusho Co., Ltd.) for 0.35 MPa for 5 minutes, and then a drum dryer (Yasuda Seiki Co., Ltd.). (Manufactured by Seisakusho) was dried at 105 ° C. for 2 minutes to prepare three handsheets having a basis weight of about 60 g / m ² . The handsheet was conditioned for 17 hours in a constant temperature and humidity chamber (temperature 23 ° C., humidity 50%).

(2) Evaluation of paper volume improvement effect The basis weight of the handsheet was measured according to JIS P8124. Further, the thickness was measured 10 points per handsheet using a JIS paper pressure measuring device MEI-10 (manufactured by Citizen Watch Co., Ltd.), and the average of the thicknesses of 10 points was taken as the thickness of the handsheet. The handsheet capacity was determined from the following formula (3) using the measured basis weight and thickness. Next, the sheet capacity of the handsheet without additive for paper (Comparative Example 1) was determined in the same procedure. The specific capacity was calculated from the following formula (4), the average value of the three sheets was obtained, and evaluated according to the following criteria. The results are shown in Table 5.

Handsheet capacity (cm ³ / g) = thickness (μm) / basis weight (g / m ² ) (3)
Specific capacity (%) = V / V ₀ × 100 (4)
V: handmade at the time of the addition of additives for paper sheet capacity V _0: handmade sheet capacity paper additives is at the time of no addition

(Evaluation criteria)
Specific capacity is 110% or more: very good (◎)
Specific capacity is 105% or more and less than 110%: good (◯)
Specific capacity is less than 105%: insufficient (×)

(3) Evaluation of suppression effect of paper strength reduction The internal bonding strength (paper strength) of the handsheet was measured with an internal bond tester (Kumagaya Riki Kogyo Co., Ltd., TAPPI-T569 compliant). Each example was measured 6 times, and the average value of the internal binding force was obtained. Subsequently, the sheet | seat internal bond strength of the handsheet (Comparative Example 1) to which the paper additive was not added was determined in the same procedure. The internal bond strength with respect to the blank was calculated from the following formula (5), and the average value of the three sheets was obtained and evaluated according to the following criteria. The results are shown in Table 5.

Inner bonding force against blank (%) = S / S ₀ × 100 (5)
S: Internal binding force of the handsheet when the paper additive is added S ₀ : Internal binding force of the handsheet when the paper additive is not added

(Evaluation criteria)
The internal bond strength with respect to the blank is 70% or more: paper strength reduction is suppressed (○)
The internal bond strength with respect to the blank is less than 70%: the suppression of the decrease in paper strength is insufficient (×)

〔Evaluation results〕
In each of Examples 1 to 5 using the paper additive of the present invention, the specific capacity is 105% or more, and the internal bond strength to the blank is 70% or more, and the paper capacity is improved and the paper strength is suppressed. Was compatible.

  On the other hand, since Comparative Example 2 uses an amidoamine compound (B′-1) produced from a polyamine that does not satisfy the provisions of the present invention, the improvement in paper capacity was insufficient. In Comparative Example 3, since the total amine value of the paper additive used in the dispersion (7) exceeds the specified upper limit of the present invention, the paper capacity improvement is small. This is thought to be because the hydrophilicity of the paper additive became too high, and the amount of fixing to the pulp fiber decreased. In Comparative Example 4, when preparing the amidoamine compound (B′-2), caprylic acid, which is an aliphatic monocarboxylic acid having 8 carbon atoms lower than the lower limit defined in the present invention, is used. It was small. Since Comparative Example 5 did not contain polyoxypropylene polyamine, the decrease in internal binding force was large, and a good paper capacity improvement effect and a suppression of paper strength reduction could not be achieved at the same time. Since the comparative example 6 mix | blended hexamethylenediamine different from polyoxypropylene polyamine, the fall of internal binding force was large, and the favorable paper capacity improvement effect and suppression of the paper strength fall were not compatible.

Claims (1)

The polyoxypropylene polyamine (A) represented by the formula (1) and 1 mol of the polyamine represented by the formula (2) are condensed with 1 to 5 mol of an aliphatic monocarboxylic acid having 12 to 24 carbon atoms. The resulting amidoamine compound (B) is contained, the mass ratio (A / B) of the polyoxypropylene polyamine (A) to the amidoamine compound (B) is from 1/99 to 30/70, and the total amine value is 60 Paper additive which is ˜230 mg KOH / g.

(In the formula, Z is a dehydroxylated residue of a divalent or trivalent alcohol, OP is an oxypropylene group, a is an average added mole number of the oxypropylene group, and b is 2 or 3. .)

(In the formula, c is an integer of 2 to 5.)