JP2588395B2 - Production method of rosin emulsion sizing agent - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a rosin-based emulsion sizing agent, and more particularly, to a novel method for producing a rosin-based aqueous emulsion useful as a paper-making sizing agent. The present invention relates to a method for producing a rosin emulsion sizing agent by a reversal method using an agent.

[Prior art] Conventionally known rosin-based emulsion sizing agents are similar to known saponified aqueous solution-type reinforced rosin sizing agents in that the quality of water used in the papermaking process deteriorates and the size effect decreases due to an increase in temperature. It has recently attracted particular attention because of its resistance to

The production method of the rosin-based emulsion sizing agent is mainly a high-pressure emulsification method using a high-pressure homogenizer and an inversion method of adding a dispersant aqueous solution to a rosin-based material in a molten state and inverting the rosin-based material from a continuous phase to a dispersed phase. Are roughly divided into Although the former can obtain a rosin-based emulsion having an extremely fine particle system, it requires a large-scale emulsifying apparatus, and the latter is considerably difficult to efficiently produce a fine-particle emulsion.

In the past, emulsification of rosin-based materials by the inversion method is based on dispersion of rosin-based materials in an aqueous medium by using a small amount of alkali such as the Bevoid method in combination with a protective colloid material such as caustic soda and casein. In recent years, various synthetic surfactants have been studied as dispersants for rosin-based substances in water.

For example, as a dispersant in water by the inversion method of a fortified rosin substance, a salt of a sulfuric acid half ester of polyoxyethylene alkyl ether or polyoxyethylene alkyl aryl ether (Japanese Patent Laid-Open No. 52-77206) or polyethoxyethylene distyryl phenyl ether And the salts of sulfuric acid half esters (JP-A-55-106534).

In addition, the following general formula (Where n is an integer and M is a monovalent cation)
Compounds wherein R is an alkyl group (JP-A-57-167349);
Compounds wherein R is an alkylphenyl group (JP-A-53-13325)
No. 9) and compounds wherein R is an aryl or alkylaryl group having 2 to 8 benzene rings (JP-A-56-22348).
) Are also effective dispersants for producing rosin emulsions by the inversion method.

[Problems to be Solved by the Invention] In the recent papermaking industry, so-called machine wastewater discharged from the papermaking process is almost completely recycled from the viewpoint of strengthening the regulation of factory drainage and reducing the cost of water use. The process is being closed. As a result, the quality of the water tends to deteriorate, and the effects of various additives tend to decrease. Especially,
It is considered that the sulfate band, which is a fixing aid of the rosin sizing agent, has various adverse effects.

The rosin-based emulsion sizing agent can exhibit a somewhat good sizing effect even when the amount of the sulfate band used is small, as compared with the saponified aqueous solution type reinforced rosin sizing agent. Rosin emulsion sizing agents obtained using the above-mentioned known dispersants are insufficient in sizing effect when the sulfate band is added at a low level, and improvement thereof has been desired. .

[Means for Solving the Problems] In order to solve the above problems, the present inventors have intensively studied the synthesis of various dispersants, the preparation of rosin-based emulsion sizing agents using them, and the evaluation of performance and the like. As a result, a new and high-performance dispersant was discovered, and a method for producing a rosin-based emulsion sizing agent having an excellent size effect when a sulfate band was added at a low level was successfully developed.

That is, the present invention forms a dispersion in which a molten rosin-based material and water containing a dispersant are mixed and stirred to form a dispersion in which the rosin-based material is a continuous phase and water is a dispersed phase. In the method for producing a rosin emulsion sizing agent for producing an aqueous emulsion in which water is a continuous phase and a rosin-based material is a dispersed phase by adding a dispersant, the dispersant has a general formula: (Wherein, R ₁ and R ₂ represent a monovalent hydrocarbon residue,
And the total number of carbon atoms in R ₁ and R ₂ is 8 to 30, X and Y
Represents one group of —SO ₃ M and the other represents a hydrogen atom, and n represents 1
Represents an integer of 0 to 30, and M represents a monovalent cation. )).

R ₁ and R _{2 in the} above general formula, that is, as the monovalent hydrocarbon residue, an alkyl group, a cycloalkyl group, an alkenyl group, a straight chain selected from a cycloalkenyl group,
In addition to branched or cyclic aliphatic hydrocarbon residues, examples thereof include aromatic hydrocarbon residues such as an aryl group, an alkylaryl group, an aralkylenyl group, and an aralkylaryl group.
It should be understood that _one of R ₁ and R ₂ may be an aliphatic hydrocarbon group and the other may be an aromatic hydrocarbon residue. R ₁ and
The total number of carbon atoms of R ₂ is preferably in the range of 8 to 30 from the viewpoint of dispersibility in water for rosin-based substances. In the above general formula, the value of n is preferably 10 to 30, and examples of the monovalent cation of M include alkali metal ions such as sodium and potassium, ammonium ions and hydrogen ions based on ammonia and various amines. be able to.

The rosin-based material used in the present invention includes a fortified rosin material which is generally suitable as a sizing material. The fortified rosin substance is obtained by heat addition reaction of rosin with α, β-unsaturated polybasic acid, and generally reacts about 5 to 15 parts by weight of α, β-unsaturated polybasic acid with respect to 100 parts by weight of rosin. Lean fortified rosin materials are preferably used. Such an enriched rosin material is a mixture of an equimolar addition product of rosin with an α, β-unsaturated polybasic acid and unreacted rosin. Here, as rosin, gum rosin, wood rosin, tall oil rosin, modified products thereof or mixtures thereof are used, and as α, β-unsaturated polybasic acids, maleic acid, itaconic acid, maleic anhydride, etc. are used. Is done. Further, in addition to rosin and α, β-unsaturated polybasic acid, a phenol-modified rosin material obtained by reacting a resol type phenol-formaldehyde initial condensate can be used, and a rosin obtained from such a phenol-modified rosin material can be used. A system emulsion sizing agent can exhibit a particularly excellent sizing effect.

Further, if necessary, in addition to the above-mentioned reinforced rosin substance, various known hydrophobic substances, for example, waxes such as paraffin wax and microcrystalline wax, and hydrocarbon resins such as petroleum resin and terpene resin can be used.

In the practice of the present invention, an aqueous solution containing the dispersant represented by the above general formula was added dropwise to the melt of the rosin-based material and sufficiently stirred to form a homogeneous dispersion in which the rosin-based material was a continuous phase. Thereafter, the phase is reversed by adding warm water under sufficient stirring to form an aqueous emulsion having a rosin-based material as a dispersed phase. At this time, the aqueous solution of the dispersant contains 2 to 10% of the dispersant based on the weight of the rosin-based material used, and the total amount of the aqueous solution is preferably 15 to 35% by weight of the weight of the rosin-based material. In this range, the mixture of the molten rosin-based substance and the aqueous solution of the dispersant forms a homogeneous dispersion having the rosin-based substance as a continuous phase. Of course, the amount of water used in the aqueous dispersant solution may be appropriately adjusted within a range in which the mixture of the two exhibits the above appearance. Also, the dropping of the aqueous dispersant solution to the molten rosin-based material is generally performed at a melting temperature higher than the melting point of the rosin-based material by 20 ° C. or more, and the temperature of the mixture after the dropping of the aqueous dispersant solution is about 100 ° C. It is preferable to adjust as follows. Thereafter, hot water at 80 to 95 ° C. is added dropwise with stirring to invert the phase, thereby obtaining a fine rosin-based emulsion sizing agent in which the rosin-based substance is a dispersed phase.

In the production of the rosin-based emulsion sizing agent according to the present invention, it is possible to use a small amount of a surfactant having another chemical structure in addition to the above-mentioned specific dispersant.

[Operation] The rosin-based emulsion sizing agent obtained by the method of the present invention having the above-mentioned constitution can exhibit a good sizing effect even when the amount of the sulfate band used as a fixing aid is small. At present, the present inventors can not clearly achieve this, but due to the exceptionally excellent dispersing effect on the rosin-based material based on the chemical structure of the dispersant used in the present invention, extremely fine dispersion It is presumed that an aqueous emulsion of a rosin-based substance composed of particles is obtained, and that the rosin-based substance particles are stabilized in a state in which the reactivity between the particles and the sulfate band is enhanced.

[Examples] Hereinafter, the present invention will be specifically described based on examples and comparative examples.

Preparation Example 1 (Preparation of Dispersant Used in the Present Invention) An α, γ-dialkyl ether glycerol was synthesized by an equimolar addition reaction of 2-ethylhexyl glycidyl ether and 2-ethylhexanol, followed by addition reaction of ethylene oxide. Thus, α, γ-dialkyl ether glycerol-β-polyoxyethylene was prepared. This was half-esterified with maleic anhydride, and sodium bisulfite was added to obtain a dispersant (a) having the following formula.

Preparation Example 2 (Preparation of Dispersant Used in the Present Invention) Using phenylglycidyl ether and lauryl alcohol, α-phenyl-γ-alkyl ether glycerol was synthesized, and the same reaction as in Preparation Example 1 was carried out. A dispersant (b) having the formula was obtained.

Preparation Example 3 (Preparation of phenol-modified fortified rosin substance) To 100 parts of rosin, 3.7 parts of a resol-type phenol formaldehyde initial condensate was added, and the mixture was reacted at 160 to 170 ° C. for 1 hour. Then, 1.5 parts of maleic anhydride and 7.5 parts of fumaric acid were added. And reacted at 190-200 ° C. to confirm that substantially no free maleic anhydride and fumaric acid were present.
The reaction was completed. The phenol-modified fortified rosin material had an acid value of 220 and a melting point of 92 ° C.

Example 1 A reactor equipped with a stirrer, a thermometer, a dropping funnel, and a condenser was charged with 100 parts by weight of the phenol-modified rosin material obtained in Preparation Example 3, and heated and melted at 140 ° C. Then, 30 parts by weight of an aqueous solution of the dispersant containing 5 parts by weight of the dispersant (a) obtained in Preparation Example 1 was added with stirring to form a homogeneous dispersion in which the rosin-based substance was a continuous phase. At this time, the temperature of the dispersion was 96 ° C. Subsequently, 70 parts by weight of hot water at 90 ° C. was added dropwise with stirring to cause phase inversion to obtain an aqueous emulsion of a rosin-based substance having a uniform fine particle diameter. After that, immediately cool to 30 ℃ or less, add normal temperature water
Was adjusted.

Table 1 shows the properties of the rosin emulsion sizing agent of the present invention thus obtained and the test results of its size effect.

Example 2 As a dispersant aqueous solution, 30 parts by weight of a dispersant aqueous solution containing 5 parts by weight of the dispersant (a) of Preparation Example 1 and 1 part by weight of sodium dodecylbenzenesulfonate was used. All others are Example 1.
The rosin emulsion sizing agent of the present invention was obtained in the same manner as described above. Table 1 shows the properties and size effects.

Example 3 As a dispersant aqueous solution, 30 parts by weight of a dispersant aqueous solution containing 5 parts by weight of the dispersant (a) of Preparation Example 1 and 0.4 part by weight of potassium hydroxide was used. All other operations were the same as in Example 1 to obtain a rosin emulsion sizing agent of the present invention. Table 1 shows the properties and size effects.

Comparative Example 1 (method based on JP-A-57-167349) Instead of using the dispersant (a) in Example 1, a sulfosuccinic acid half ester salt of polyoxyethylene alkyl ether (trade name: SOFTANOL MES-12) , Manufactured by Nippon Shokubai Chemical Industry Co., Ltd.). All other operations were the same as in Example 1 to obtain a rosin-based emulsion sizing agent for comparison. The properties and size effects are shown in Table 1.

Comparative Example 2 (method based on JP-A-53-133259) A sulfosuccinic acid half-ester salt of polyoxyethylene alkylphenyl ether (trade name: Aerosol A-103) was used instead of the dispersant (a) in Example 1. , Manufactured by Mitsui Cyanamid Co., Ltd.). All other operations were the same as in Example 1 to obtain a rosin-based emulsion sizing agent for comparison. The properties and size effects are shown in Table 1.

Comparative Example 3 (method based on JP-A-55-106534) A half-sulfuric acid salt of polyoxyethylene (15 moles of EO added) distyryl phenyl ether instead of using the dispersant (a) in Example 1 It was used. All other operations were the same as in Example 1 to obtain a rosin-based emulsion sizing agent for comparison. The properties and size effects are shown in Table 1.

<Test method> (i) Appearance After collecting 50 cc of the sizing agent in a 200 cc transparent glass bottle, sealing the bottle, invert the bottle, and allow to stand. The state in which the sizing agent flowed down as a thin layer on the wall surface was visually observed, and judged based on the following criteria.

：: No coarse particles are present, and a clear feeling appears within 10 seconds.

：: No coarse particles are present, and a clear feeling appears after about 20 seconds.

Δ: Slight coarse particles are present, and after 20 seconds or more, a transparent feeling appears.

(Ii) Permeability A diluent of 0.05% (solid content) of a sizing agent was prepared using deionized water, and a diffraction grating type photoelectric colorimeter (Spectronic 20;
The light transmittance at a wavelength of 560 nm was measured by Shimadzu Corporation. The transmittance of deionized water is 100%, and the higher the transmittance, the finer the dispersed particle size of the sizing sample.

(Iii) Size effect To a 2.4% pulp slurry of L-BKP (CSF400ml), add 20% of talc and 0.2% of rosin-based emulsion sizing agent to dry pulp weight, mix well, and then mix with sulfuric acid band. Predetermined amount (shown in Tables 1 and 2 below)
Was added to obtain a prepared pulp slurry. Next, hand-sheeting is performed using a standard TAPPI sheet machine according to a standard method,
After dewatering at 3.5 kg / cm ^2, a drum dryer (surface temperature 70
C.) for 1 minute to prepare a hand-made paper. The obtained handmade paper was equivalent to an adult paper weight of 60 g / cm ^2, and after humidity control, was measured for the sizing degree according to JIS;

Examples 4 and 5 In a reactor equipped with a stirrer, a thermometer, a dropping funnel and a condenser, 100 parts by weight of the phenol-modified rosin material obtained in Preparation Example 3 was charged, and heated and melted at 140 ° C. Next, an aqueous dispersant solution containing the dispersant (b) of Preparation Example 2 prepared in advance was added through a dropping funnel, and a homogeneous dispersion in which the rosin-based material was a continuous phase was produced with sufficient stirring. Subsequently, 70 parts by weight of 90 ° C. warm water was dropped under strong stirring to cause phase inversion, thereby obtaining an aqueous emulsion of a rosin-based substance having a uniform fine particle diameter. Thereafter, the mixture was immediately cooled, and normal temperature water was added to obtain a rosin-based emulsion sizing agent having a concentration of 50%. Table 2 shows the composition of the aqueous dispersant solution used, and the properties and size effects of the obtained rosin emulsion sizing agent.

[Effects of the Invention] As is clear from the above description, the rosin-based emulsion sizing agent obtained by the present invention has a dispersed phase composed of a rosin-based material which is very finely and stably dispersed, and has an excellent size effect. In particular, it has a special effect that the size effect when the sulfuric acid band is added at a low level is good.
Therefore, the sizing agent has high industrial value as a sizing agent that can cope with the deterioration of the quality of water due to the closed papermaking process and the like.

Claims (1)

(57) [Claims] (1) mixing and stirring a molten rosin-based material and water containing a dispersant to form a dispersion in which the rosin-based material is a continuous phase and water is a dispersed phase, and then water is added to the dispersion; In the method for producing a rosin-based emulsion sizing agent in which an aqueous emulsion in which water is a continuous phase and a rosin-based substance is a dispersed phase is produced by inverting the phase by addition, the dispersant has a general formula (Wherein, R ₁ and R ₂ represent a monovalent hydrocarbon residue,
R ₁ and R ₂ have a total of 8 to 30 carbon atoms, one of X and Y is a —SO ₃ M group, the other is a hydrogen atom, and n is 10 to 30.
And M represents a monovalent cation. A method for producing a rosin-based emulsion sizing agent comprising the compound of the above).