JPS584938B2 - Process for making aqueous emulsion of rosin material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for making an aqueous emulsion of a rosin material, and more particularly to a method for making an aqueous emulsion of a rosin material by an inversion process using a specific dispersant.

Cellulose fiber products such as paper, paperboard, and wood fiberboard are generally made by adding a sizing agent to an aqueous dispersion of cellulose fibers, and the sizing agent usually imparts water resistance and ink bleed resistance to the resulting product. Reinforced rosin-based sizing agents are widely used because of their ability to impart such properties, and recently, aqueous emulsion sizing agents have attracted attention as such sizing agents.

The sizing agent can be produced by dispersing the reinforced rosin in water using a high-pressure shearing homogenizer in the presence of an appropriate dispersant, and by inverting an emulsion of the reinforced rosin containing an appropriate dispersant. Recently, an inversion method using a sulfuric ester salt of polyoxyethylene alkyl phenyl ether as a dispersant for stabilizing reinforced rosin has been proposed (Japanese Patent Application Laid-Open No. 77206/1983).

However, the emulsion obtained by this method was not sufficient in terms of stability, especially mechanical stability.

The present inventors have long sought to provide a method for producing an aqueous emulsion of a rosin material that is excellent in stability and can impart an excellent size effect to paper formation, and in particular, a dispersion for stabilizing a rosin material. We have conducted various research on the drug.

However, no systematic research has been conducted on dispersants for stabilizing rosin materials, and even if compounds with similar structures and similar surfactants generally have similar stabilizing effects on rosin materials, their stabilizing effects on rosin materials are generally not related at all. It is difficult to develop a dispersant that can exhibit an excellent stabilizing effect equivalent to or even better than that of the dispersant described in the above-mentioned JP-A-Sho from among compounds that have no surfactant properties and have the same surfactant effect as the dispersant described in JP-A-Sho. it was thought.

However, in subsequent research, a rosin material was produced using phase inversion in the presence of a specific sulfonate represented by the following general formula [I], which had never been used to produce an aqueous emulsion of this type of rosin material. When dispersed in water, it has excellent stability and size AIM that meets the above objectives.
It has been found that it is possible to obtain an aqueous emulsion of a rosin material that has a high level of properties and has low foaming properties.

The present invention was completed based on this new knowledge.

That is, the present invention involves mixing a molten rosin material, a dispersant, and water to form an emulsion in which the rosin material is a continuous phase and water is a dispersed phase, and then adding water and inverting the emulsion to form a rosin material. When obtaining an aqueous emulsion in which the dispersed phase is water and the continuous phase is water, the above-mentioned dispersant is used as the general formula [where R is a hydrocarbon residue having 4 to 18 carbon atoms, m is 1 or 2, and n is an integer of 4 to 25] , X represents a hydrogen atom or a hydroxyl group, and M represents a monovalent cation.

According to the method of the present invention, the rosin substance is dispersed in water using phase inversion as described above, and the method uses a specific dispersing agent represented by the above general formula [■]. It is possible to easily obtain an aqueous emulsion of a rosin material that has stability and suitability as a sizing agent and has low foaming properties.

In particular, the method of the present invention allows an aqueous emulsion having the above-mentioned excellent properties to be obtained even when the specific dispersant represented by the general formula [I] is used in a small amount of about 2% by weight based on the dry weight of the rosin material. can.

This effect cannot be expected at all with the method described in JP-A-52-77206 in which a sulfuric ester salt of polyoxyethylene alkyl phenyl ether is used as a dispersant.

In fact, in the above method, as shown in Tables 1 and 2 below as comparative examples, when the amount of dispersant used is 2% by weight,
The resulting emulsion is unstable and becomes unsuitable for use because it becomes water-separated in about a day, and even before water-separation, its size effect is extremely poor and is of little practical use.

In addition, in the above-mentioned method using a known dispersant, the stability is somewhat improved by increasing the amount of the dispersant (for example, 4% by weight), but the mechanical stability is still not sufficient, and furthermore, when the amount of the dispersant is increased, the stability is improved to some extent. When this is done, there is a disadvantage that the foaming property increases significantly and it takes a long time to defoam, and it is not economically preferable at all.

The rosin material used as a dispersion material in the present invention is usually 0 to 95% by weight of rosin and 5 to 100% by weight of reinforced rosin.
% by weight, including the addition of a fortified rosin filler, if necessary, up to 50% by weight of the total.

As the rosin, gum rosin, wood rosin, tall oil rosin, modified products thereof, and mixtures thereof can be used.

Examples of the above-mentioned modified products include hydrogenated rosin, disproportionated rosin, polymerized rosin, and aldehyde-modified rosin.

Among these rosins, for example, aldehyde-modified rosin is usually made by mixing rosin and 2 to 8% by weight of formaldehyde or acetaldehyde in the presence of an acidic catalyst such as sulfuric acid or para-toluenesulfonic acid at a temperature of about 140 to 200°C.
It is obtained by reacting for 5 to 3 hours.

The reinforced rosin is made by combining the above rosin and 2 to 30% by weight, preferably 3 to 15% by weight of α,β monounsaturated carboxylic acid.
It is obtained by a heating reaction at a temperature of about 50 to 250°C.

The α,β-monounsaturated carboxylic acids used include acrylic acid, maleic acid, fumaric acid, iconic acid, their anhydrides and mixtures thereof, with fumaric acid, maleic acid and maleic anhydride being particularly preferred.

Examples of the reinforced rosin extender that may be included in the rosin substance include waxes such as paraffin wax and microcrystalline wax, petroleum resins, terpene resins, and hydrocarbon resins such as hydrogenated products thereof.

Rosin materials containing these are usually at least 25% by weight.
Preferably, it contains a fortified rosin.

In the present invention, it is essential to use a sulfonate represented by the above general formula [I] as a dispersant.

4 to 18 carbon atoms represented by R in the general formula [■]
The hydrocarbon residues include straight-chain or branched alkyl groups, specifically butyl, isobutyl, hexyl, octyl, isooctyl, nonyl, isononyl, dodecyl,
Tetradecyl, hexadecyl, octadecyl groups, etc. and formulas (where R1 is a hydrogen atom or a lower alkyl group such as methyl, ethyl, propyl, butyl group, etc., and A is a linear or branched alkylene having 1 to 3 carbon atoms) For example, aromatic hydrocarbon residues represented by methylene, methylmethylene, ethylene, methylethylene, trimethylene groups, etc. are included.

In the above, when R represents a linear or branched alkyl group, the total number of carbon atoms in the group represented by (R) is 4 to 3.
0, particularly preferably 6 to 25.

Further, when R represents an aromatic hydrocarbon residue represented by the above formula, m is preferably 2, and the total number of carbon atoms of the group represented by (R)m is preferably 14 to 20.

Preferred examples of the group represented by (R)m include a distyryl group, a di(ρ-methylstyryl) group, and a di(α-methylstyryl) group.

Further, in the present invention, as the sulfonic acid salt represented by the above general formula [I], it is particularly preferable to use one in which n is 6 to 17, and furthermore, two or more types of sulfonic acid salts in which n is 4 to 25 are mixed, It is also a preferred embodiment that the average value n is 6 to 17.

In the sulfonate represented by the above general formula [I], M
Examples of the monovalent cation defined in the formula include alkali metal ions such as lithium, sodium, potassium, and cesium, and ammonium groups derived from ammonia and various amines such as trimethylamine, dimethylamine, diethylamine, and triethanol.

The dispersant is generally used in an amount of about 0.5 to 10% by weight, preferably about 1 to 8% by weight, based on the dry weight of the rosin material.

If it is less than 0.5% by weight, the dispersing power is insufficient;
It is not economical to use more than this amount.

In particular, the dispersant represented by the above general formula [I] used in the present invention has the advantage that an aqueous emulsion capable of exhibiting the desired effect can be obtained even when it is used in a small amount, for example, about 1 to 2% by weight. .

To carry out the manufacturing method of the present invention, a molten rosin material is first prepared by heating and stirring the fortified rosin, optionally with rosin and/or filler.

The heating temperature at this time should be set at least 20 degrees Celsius higher than the softening point of the rosin material.The appropriate temperature is generally in the range of 90 to 160 degrees Celsius, depending on the blending ratio of the reinforced rosin, rosins, and fillers. It is.

An aqueous dispersant solution or a dispersant and water is then added to the molten rosin material while stirring to form an emulsion in which the rosin material is the continuous phase and water is the dispersed phase.

The amount of water used at this time is approximately 7
It is preferable to adjust the solid content to 0 to 90% by weight.

Hot water (invert water) at about 70-100° C. is then added to the emulsion with vigorous stirring.

Phase inversion of the emulsion occurs when the amount of water exceeds about 30% of the total amount, and water becomes the continuous phase, resulting in an emulsion in which the rosin material is dispersed in water.

If desired, this emulsion can be diluted and/or pH adjusted with water or alkaline water.

The amount of the alkali used is preferably such that the pH of the emulsion is 6 or less.

The aqueous emulsion thus obtained usually contains 5 to 70% by weight of the rosin material, preferably 30 to 55% by weight, and 0.5 to 10% by weight, preferably 1 to 8% by weight of the rosin material as a dispersant. The emulsion consists of a compound represented by the formula and 100% by weight of water, and the rosin material is uniformly dispersed in the emulsion as particles of about 1 micron or less, mostly about 0.5 micron or less.

Moreover, the aqueous emulsion exhibits a milky appearance; 3.
It has a pH of 5-6.

It is stable at room temperature for at least two months, does not precipitate, and exhibits very little foaming typically associated with the use of dispersants.

Furthermore, it has excellent mechanical stability and dilution stability as shown in the Examples below.

The aqueous emulsion obtained according to the present invention can be produced not only by making cellulose fibers, but also by making a mixture of the cellulose fibers and mineral fibers such as asbestos, rock wool, etc. or synthetic fibers such as polyamide, polyester, polyolefin, etc. to produce paper, paperboard, etc.
It can be advantageously applied to manufacturing fiberboards and the like.

When the aqueous emulsion obtained according to the present invention is used as a sizing agent for paper manufacturing, for example, it can be added to an aqueous dispersion of pulp together with a fixing agent such as sulfuric acid and made into paper at a pH of 4 to 6, or as described in Japanese Patent Publication No. 49-30201. As described above, a method can be adopted in which paper is made by adding a small amount of a fixing agent such as sulfuric acid or the like and a very small amount of a cationic fixing aid to an aqueous dispersion of pulp at a pH of 5 to 7.

In this case, the aqueous emulsion is 0.05% of the pulp
It is used at about 3% by weight (dry weight basis).

The aqueous emulsion obtained by the present invention also has excellent dilution stability, so it can be sufficiently diluted with water from rivers, taps, wells, etc., and is well dispersed in an aqueous pulp dispersion.

Moreover, the diluted solution is stable for a long time.

The aqueous emulsion obtained by the present invention can also be used as a surface sizing agent, and can be sprayed, dipped, or
It is applied by conventional methods such as painting.

The method for producing the aqueous emulsion of the present invention will be explained in more detail below with reference to Examples.

Note that the reference example shows an example of manufacturing the rosin material used in the present invention.

Examples Middle and percentages are based on weight unless otherwise specified.

Reference Example 1 1800 parts of tall oil rosin is heated and melted, and 2.7 parts of p-1-luenesulfonic acid monohydrate is added as a catalyst while stirring at 165°C.

Then, 118 parts of a 37% formaldehyde aqueous solution was added to 160 parts.
Addition takes 90 minutes at ~170°C.

Stir for another 1 hour at the same temperature to obtain formaldehyde-modified rosin.3 To this modified rosin, gum rosin 12
00 parts and stirred and mixed at 175°C for 1 hour.

2950 parts of the above mixture and 177 parts of fumaric acid were heated and melted and reacted at 200°C for 3 hours.

The obtained rosin substance (1) has an acid value of 208 and a softening point (ring and ball method) of 103.5°C.

Reference Example 2 1000 parts of gum rosin and 190 parts of fumaric acid are heated and melted to 200°C, and reacted at the same temperature for 4 hours.

The obtained reinforced rosin has an acid value of 286 and a softening point of 138.5°C.
It is.

550 parts of the reinforced rosin and 500 parts of gum rosin obtained above were heated to 170°C and mixed for 30 minutes to form the rosin material...
).

Examples 1 and 2 Into a flask equipped with a stirrer and a thermometer, l o o parts of the rosin substance (I) of Reference Example 10 was charged and melted by heating to 150 g.
It reached ℃.

While stirring, add 2-hydroxy-3-(distyrylphenoxypolyoxyethylene)propylsulfonic acid sorter (
The compound represented by the general formula [I], m-2, n
13) 20% aqueous solution of 10 parts (Example 1) and 20 parts (
Each of Example 2) was added to the molten rosin material over a period of 2-3 minutes.

At this point, significant water had evaporated and the temperature had dropped to 93°C.

Then, 20 parts of hot water (95°C) was added to form a creamy water-in-oil emulsion.

While vigorously stirring the emulsion, 70 parts of hot water (90° C.) was further added over 1 minute to cause phase inversion, resulting in an oil-in-water emulsion.

This is rapidly cooled from the outside to reduce the temperature to 30℃,
It was passed through a 100 mesh wire mesh and placed in a glass bottle.

No coagulum was observed on the wire mesh, and the rosin material contained in the resulting aqueous emulsion had substantially the same weight as the rosin material used (yield: 98% or more).

The properties of the obtained emulsion are shown in Table 1.

Comparative Examples 1 and 2 Polyoxyethylene (average polymerization K 10
) An aqueous emulsion was obtained in the same manner except that the sodium salt of nonylphenyl ether sulfate half ester was used.

The properties of the obtained aqueous emulsion are shown in Table 1.

In addition, each property of the aqueous emulsion in the table was measured by the following method.

(1) Mechanical stability 50 g of the aqueous emulsion was weighed into a container of a Marlon stability tester (manufactured by Shinsei Sangyo Co., Ltd.), and the temperature was 25°C, the load was 10 kg, and the rotation speed was 100 r. p. After applying mechanical shear for 5 minutes at
Filter it through a mesh wire gauze, and calculate the mechanical stability according to the following formula.

(2) Dilution stability The aqueous emulsion is diluted to a concentration of 5% with water having a hardness of 10° DH at 25°C.

After dilution, the time required for the emulsion to coagulate and form flocs is measured with the naked eye.

(3) The foamable aqueous emulsion was diluted with deionized water to a concentration of 500 ppm, and the diluted solution was measured according to JIS K3362.

From Table 1 above, the method of the present invention, based on the use of the specific dispersant represented by the general formula CI), has improved mechanical stability, dilution stability, and storage stability compared to the case of using known dispersants. It can be seen that an aqueous emulsion with excellent stability and considerably low foaming property can be obtained.

In particular, according to the method of the present invention, the desired aqueous emulsion that is stable for more than two months can be obtained by using only 2% by weight (dry weight basis) of the above-mentioned dispersant based on the rosin material, whereas the known dispersant is only 2% by weight (dry weight basis). %, only unstable emulsions that become water-separated in just one day can be obtained.

<Practical Test> When the aqueous emulsions obtained in Examples 1 to 2 and Comparative Examples 1 to 2 were used as paper sizing agents, the sizing degree (seconds) of the paper was determined by the Stekicht method (115 P 81
22).

That is, a pulp (L-BKP) with a freeness of 30°SR is made into a 1% aqueous slurry, and a 0.0% aqueous slurry is prepared based on the dry weight of the pulp.
2% or 0.5% aqueous emulsion then 2.5%
After adding chemicals in the order of sulfuric acid bands and uniformly dispersing them, paper is made using a TAPPI standard sheet machine so that the basis weight is 60±1 g/m.

This was dehydrated for 3 minutes at a pressure of 5 kg/cm' and then
℃ for 5 minutes and the paper stock was dried at 20℃ and 65SR. H. After conditioning the humidity for 24 hours under the following conditions, measure the size effect.

The results are shown in Table 2. From Table 2 above, the aqueous emulsion obtained by the method of the present invention uses only 2% by weight (dry weight basis) of the dispersant represented by the general formula [■] based on the rosin material, and 4% by weight of the known dispersant. It is clear that approximately the same size effect can be achieved as the emulsion obtained using %.

On the other hand, an aqueous emulsion obtained using 2% by weight of a known dispersant exhibits an extremely low size effect even when used at 0.5% based on the dry weight of the pulp, which may be difficult to put into practical use. I understand.

Example 3 and Comparative Example 3 Aqueous emulsions were obtained in the same manner as in Example 1 except that the amount of dispersant used was 1% based on the rosin material.

Comparative Example 1 was carried out in the same manner as in Comparative Example 1 except that the amount of dispersant used was 1% based on the rosin substance, but no phase inversion occurred and an oil-in-water emulsion could not be obtained.

Examples 4 to 13 Rosin substance (II) was used in place of rosin substance (1), and the compounds shown in Table 3 below were used as a dispersant in rosin substance (II).
) A stable aqueous emulsion was obtained in the same manner except that 4% of the emulsion was used.

The yield was approximately 100%, the particle size of each emulsion was 0.2 to 0.3 μ, the dilution stability was 24 hours or more, and the emulsions could be stored stably for 2 months or more.

Table 4 shows the results of measuring the mechanical stability and foaming properties of these emulsions, and the results of using them as paper sizing agents according to the above-mentioned method.

Claims (1)

Claims: 1. Mixing a molten rosin material, a dispersant, and water to form an emulsion in which the rosin material is a continuous phase and water is a dispersed phase, and then inverting the emulsion by adding water. When obtaining an aqueous emulsion in which the rosin substance is a dispersed phase and water is a continuous phase, the above-mentioned dispersant is used as the general formula [wherein R is a hydrocarbon residue having 4 to 18 carbon atoms, m is 1 or 2, and n is 4 to 4]. 1. A method for producing an aqueous emulsion of a rosin material, characterized in that one or more sulfonic acid salts are used, each of which is an integer of 25, X is a hydrogen atom or a hydroxyl group, and M is a monovalent cation. 2. The method according to claim 1, which uses a sulfonate represented by the above general formula [I], in which R represents a linear or branched alkyl group. 3 R represents an aromatic hydrocarbon residue represented by the formula (wherein R1 is a hydrogen atom or a lower alkyl group and A represents an alkylene chain), and m is 2
The method according to claim 1, which uses a sulfonate represented by the above general formula [1].