JPH05253465A - Production of water base emulsion of rosin material - Google Patents

Abstract

PURPOSE:To obtain a water base emulsion possible to give excellent sizing effect to paper in a wide range of pH at the time of making sheet and also excellent in dilution stability in the case of using as a sizing agent for paper making by dispersing a rosin material in water in the presence of a dispersing agent having a specific structural formula. CONSTITUTION:The water base emulsion of the rosin material is produced by dispersing the rosin material in water in the presence of the dispersing agent. In this case, one kind or two or more kinds of compounds expressed by formula I is used as the dispersing agent. In the formula I, R<1> is 4-18C alkyl, alkenyl or aralkyl group, R<2> is H, 4-18C alkyl, alkenyl or aralkyl group, R<3> is H or methyl group, A is 2-4C (substituted) alkylene group, n is integer of 1-200, M is univalent cation. The water base emulsion obtained in this way gives excellent sizing effect in the wide range of sheet making pH and is excellent in dilution stability in the case of using as the sizing agent for paper making.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an aqueous emulsion of a rosin substance using a specific dispersant.

[0002]

2. Description of the Related Art Rosin substances have hitherto been used in a wide range of fields such as paper sizing agents, tackifiers, rubber emulsifiers, paints and printing inks.
From the aspects of environmental friendliness and the like, attention has been paid to aqueous emulsification in these fields. In this specification, an aqueous emulsion sizing agent, which is particularly required to be emulsified with an aqueous solution, will be described as a representative.

Cellulose fiber products such as paper, paperboard and wood fiberboard are generally produced by adding a sizing agent to an aqueous dispersion of cellulosic fibers. Although a reinforced rosin-based sizing agent is widely used because it can impart ink bleeding resistance and the like, an aqueous emulsion sizing agent has recently attracted attention as the sizing agent. As a method for producing the aqueous emulsion sizing agent, a method in which a reinforced rosin is dispersed in water using a homogenizer having high pressure shearing force in the presence of a suitable dispersant,
There is a method of phase inversion of an emulsion of fortified rosin containing a suitable dispersant. Conventionally, a reversal method using a sulfuric acid ester salt of polyoxyethylene alkylphenyl ether as a dispersant for stabilizing a toughened rosin (JP-A-52-7)
No. 7206), an inversion method using a sulfosuccinic acid ester salt of polyoxyethylene alkylphenyl ether as the dispersant (JP-A No. 53-133259),
Inversion method using a sulfosuccinic acid ester salt of polyoxyethylene alkyl ether as the dispersant (JP-A-57-57
No. 167349) is proposed.

However, none of the emulsions obtained by these conventional methods is sufficiently stable, especially mechanical stability, and the foamability of the emulsion itself, particularly foaming during papermaking. Since it has remarkable properties, a large amount of antifoaming agent must be used during transportation and use. Further, each emulsion sizing agent obtained by these conventional methods has a drawback that the sizing effect is remarkably lowered when the papermaking pH is in a weakly acidic region of 6 to 7.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention have previously provided a method for producing an aqueous emulsion of a rosin substance, which is excellent in stability and can impart excellent size effect to papermaking in a wide papermaking pH range. For the purpose, various studies have been carried out on dispersants, especially for stabilizing rosin substances. However, no systematic research on dispersants for stabilizing rosin substances has been conducted so far, and in general, even for compounds of similar structure having similar surface activity, the stabilizing action on the rosin substance is completely unrelated. It is difficult to develop a dispersant capable of exhibiting an excellent stabilizing effect and a foam suppressing effect equivalent to or even higher than the compounds having the same surfactant activity as those of the dispersant described above, which has no property. It was considered. However, in the subsequent research, when the rosin substance was dispersed in water in the presence of a specific compound represented by the following general formula 1, which has never been used to prepare an aqueous emulsion of this kind of rosin substance, It has been found that it is possible to obtain an aqueous emulsion of a rosin substance which has excellent stability in conformity with the above and a suitability for a sizing agent in a wide range of papermaking pH range and has a low foaming property. The present invention has been completed based on this new finding.

That is, according to the present invention, when a rosin substance is dispersed in water in the presence of a dispersant to produce an aqueous emulsion of the rosin substance, the above-mentioned dispersant has the general formula:

[0007]

[Chemical 1]

(Wherein R ¹ is an alkyl group, an alkenyl group or an aralkyl group having 4 to 18 carbon atoms, R ² is hydrogen or an alkyl group, an alkenyl group or an aralkyl group having 4 to 18 carbon atoms, and R ³ is hydrogen. Or methyl group, A
Is an alkylene group having 2 to 4 carbon atoms, or a substituted alkylene group, n is an integer of 1 to 200, and M is a monovalent cation), and one or more kinds of compounds are used. The present invention relates to a method for producing an aqueous emulsion of a rosin substance.

According to the method of the present invention, as described above, when the rosin substance is dispersed in water, the specific dispersant represented by the general formula 1 is used, and the stability is remarkably excellent. A wide range of papermaking pH including weakly acidic regions of pH 6-7
It is possible to easily obtain an aqueous emulsion of a rosin substance, which has a suitability for a sizing agent in the range, has little foaming property per se, and is hardly accompanied by the problem of large foaming property in a papermaking system.

The rosin substance used as the substance to be dispersed in the present invention usually comprises 0 to 95% by weight of rosin and 5 to 100% by weight of rosin derivative, and if necessary, the rosin derivative is added up to 50% by weight. Including agents added.

As the rosin, gum rosin, wood rosin and tall oil rosin can be used alone or in a mixture thereof. Examples of the rosin derivative include hydrogenated rosin, disproportionated rosin, polymerized rosin, modified rosins such as aldehyde-modified rosin, reinforced rosins, rosin esters, reinforced rosin esters and the like. Examples of the reinforced rosin extender contained 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. The rosin material containing these usually preferably contains at least 25% by weight of the rosin derivative.

In the present invention, it is essential to use the compound represented by the general formula 1 as a dispersant. In the general formula 1, R ¹ is an alkyl group having 4 to 18 carbon atoms, an alkenyl group or an aralkyl group, and examples of the alkyl group include a butyl group, an isobutyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, Nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group and the like, and examples of the alkenyl group include butenyl group, isobutenyl group, pentenyl group, hexenyl group. Group, heptenyl group, octenyl group,
Examples include nonenyl group, decenyl group, undecenyl group, tridecenyl group, tetradecenyl group, pentadecenyl group, heptadecenyl group, octadecenyl group, and the like, and aralkyl groups include, for example, styryl group, benzyl group, cumyl group, and the like. May be

R ² is hydrogen or an alkyl group, an alkenyl group or an aralkyl group having 4 to 18 carbon atoms, and the alkyl group, the alkenyl group or the aralkyl group is the same as that of R ^1, and these are a mixture. It may be. R ³ is hydrogen or a methyl group.

A is an alkylene group having 2 to 4 carbon atoms or a substituted alkylene group, specifically, an ethylene group,
Examples thereof include a propylene group, a butylene group, and an isobutylene group. These alkylene oxides may be individually added, randomly added, or block added.

N is an integer of 1 to 200, more preferably 2 to 100. Further, as the monovalent cation defined by M, an alkali metal ion such as lithium, sodium and potassium, an ammonium group derived from ammonia and various amines such as triethylamine, dimethylamine and triethanolamine can be presented.

The compound represented by the general formula 1 used as the dispersant is, for example, the corresponding known alkyl,
Alkenyl or aralkylphenol is heated and reacted with allyl chloride or methallyl chloride in the presence of a catalyst, and then the reaction product obtained by distillation under reduced pressure is further added with an alkylene oxide, followed by sulfation of sulfuric acid, sulfamic acid or the like. It can be easily synthesized by sulfating with an agent and, if necessary, neutralizing with an alkaline substance which becomes the cation.

The method of the present invention is usually carried out according to the inversion method. In the case of the inversion method, the dispersant is usually about 0.5 to 10% by weight, preferably 1 to 8% by weight based on the dry weight of the rosin substance. Used in a percentage by weight. If the amount is less than 0.5% by weight, the dispersibility is insufficient, and it is not economical to use the amount exceeding 10% by weight. Particularly, the dispersant represented by the general formula 1 used in the present invention contains, for example, 1 to 2% by weight.
Even when used in a small amount, there is an advantage that an aqueous emulsion capable of exhibiting a desired effect can be obtained.

More specifically, the above method is carried out as follows. That is, first, a rosin derivative is heated and stirred together with either or both of a rosin and a bulking agent, if desired, to prepare a molten rosin substance. The heating temperature at that time is preferably set at a temperature higher by at least 20 ° C. than the softening point of the rosin substance, and an appropriate temperature depends on the compounding ratio of the rosin derivative, the rosin and the extender, but generally 90
Is in the range of ~ 160 ° C.

The molten rosin substance is then added to this while adding the aqueous dispersant solution or the dispersant and water to form an emulsion in which the rosin substance is the continuous phase and the water is the dispersed phase. The amount of water used here should be adjusted so that the resulting emulsion contains about 70 to 90% by weight of solids.

Next, hot water (reversed water) of about 70 to 100 ° C.
Is added to the emulsion with vigorous stirring. The phase inversion of the emulsion is such that the solid content concentration is 60 to 70% by weight.
It occurs when water is added so that it becomes a continuous phase, and an emulsion in a form in which a rosin substance is dispersed in water is obtained. If desired, this emulsion can be diluted and / or pH adjusted with water or alkaline water. It is preferable that the amount of alkali used is such that the pH of the emulsion is 6.5 or less. In an emulsification method using an emulsifier, for example, a rosin substance is first dissolved in a water-insoluble organic solvent to obtain a solution viscosity (25 ° C.) of 100.
The solution should be 0 cps or less, preferably 500 cps or less. In this case, the solution concentration is usually about 20 to 70% by weight, preferably 40 to 60% by weight. As the water-insoluble organic solvent, those which are azeotropic with water are preferable, and benzene, toluene, cyclohexane, carbon tetrachloride and the like can be exemplified, and benzene is particularly preferable. Next, water and a dispersant or an aqueous dispersant solution are added to the obtained organic solvent solution to carry out pre-emulsification, followed by emulsification at a temperature of about 10 to 80 ° C, preferably about 30 to 60 ° C. Here, the amount of water used is preferably adjusted so that the mixture of the rosin substance before emulsification, the organic solvent, and the water used contains 10 to 40% by weight of the rosin substance. Since the emulsion thus obtained contains an organic solvent, in this method, the organic solvent is then distilled off, preferably under reduced pressure at about 30 to 90 ° C. to obtain the desired aqueous emulsion. When the organic solvent is distilled off, a part of the water is usually distilled off together, so that the concentration of the obtained aqueous emulsion is somewhat increased.

The aqueous emulsion of the present invention can also be produced by the following method. That is, first, the rosin substance is heated and dissolved, and water and a dispersant or an aqueous solution of the dispersant are added thereto, or three members are heated at the same time, and then the molten mixture is emulsified. The temperature at the time of melting and emulsifying the rosin substance needs to be in a range that imparts fluidity to the rosin substance but does not cause its decomposition, and is generally about 140 to 200.
C., preferably temperatures of about 160-190.degree. C. are employed. The viscosity of the rosin substance melted at this temperature is 300c.
It is good to set it to ps or less, preferably 100 cps or less. As is clear from the above description, the emulsification by this method needs to be carried out in a closed container, and the internal pressure is 10
It may be about kg / cm ² . The amount of water used is appropriately determined according to the desired concentration of the resulting aqueous emulsion.

When any of the above methods is used, when using an emulsifying machine, a homogenizer, a piston type high pressure emulsifying machine, an ultrasonic emulsifying machine or the like can be used. The water used during emulsification and which is a constituent of the aqueous emulsion of the present invention does not have to be purified water, but so-called soft water is preferably used.

The aqueous emulsion thus obtained is usually 5 to 70% by weight, preferably 30 to 55% by weight, and about 0.5 to 10% by weight based on the rosin substance.
Preferably, the compound comprises the compound represented by the general formula 1 as a dispersant in an amount of about 1 to 8% by weight and water in an amount of 100% by weight, and the rosin substance is 1 μm or less in the emulsion.
Most of the particles are uniformly dispersed as particles of about 0.5 μm or less. The aqueous emulsion also has a milky white appearance,
It has a pH of 3.5-6.5. The aqueous emulsion of the present invention is stable at room temperature for at least 2 months, does not cause precipitation, and has very little foaming, which is usually associated with the use of a dispersant. Further, it has excellent mechanical stability and dilution stability as shown in Examples described later.

The aqueous emulsion obtained according to the present invention is not limited to the papermaking of cellulose fibers, but also papermaking of a mixture of the fibers and mineral fibers such as asbestos, rock wool, etc. and synthetic fibers such as polyamide, polyester, polyolefin etc. It can be advantageously applied to the production of paperboard, fiberboard and the like.

When the aqueous emulsion obtained according to the present invention is used as a sizing agent for papermaking, it is added to an aqueous dispersion of pulp together with a fixing agent such as a sulfuric acid band, and papermaking is carried out at pH 4 to 7, 49-30
As described in JP-A No. 201-201, a method of adding a fixing agent such as a sulfuric acid band and an extremely small amount of a cationic fixing agent to an aqueous dispersion of pulp and making a paper at pH 5 to 7 can be adopted, and a wide range of papermaking pH can be adopted. Within the range, an excellent size effect can be imparted to the paper. In this case, the aqueous emulsion is about 0.05 to 3% by weight with respect to the pulp (dry weight basis)
Used in. Since the aqueous emulsion obtained by the present invention has excellent dilution stability, it can be sufficiently diluted with water from rivers, taps, wells, etc. and is well dispersed in an aqueous dispersion of pulp. Moreover, the diluted solution is stable for a long time.

The aqueous emulsion obtained according to the present invention can also be used as a surface sizing agent, and in this case, it can be applied to a wet paper sheet previously made by a conventional method such as spraying, dipping or coating.
Of the aqueous emulsions obtained by the present invention, the aqueous emulsions of rosin esters and reinforced rosin esters are effectively used as tackifiers.

[0027]

EXAMPLES The method for producing the aqueous emulsion of the present invention will be described in more detail below with reference to examples. The reference example shows an example of producing a rosin substance used in the present invention. The middle part and% are based on weight unless otherwise specified.

The properties of the aqueous emulsion in the table are those measured by the following methods. (1) Mechanical stability 50 g of an aqueous emulsion was weighed in a container of a Marlon type stability tester (manufactured by Shinsei Sangyo Co., Ltd.), and the temperature was 25 ° C., the load was 10 kg, and the rotation speed was 1000 r.s. p. m. After adding a mechanical shear for 5 minutes, the generated agglomerates were filtered through a 100-mesh wire net and the mechanical stability was calculated according to the following formula. Mechanical stability (%) = (absolute dry weight of aggregate / absolute dry weight of sample emulsion) × 100 (2) Foamability (a) Dilute aqueous emulsion to a concentration of 5% with deionized water, and dilute this For the liquid, the height (mm) of bubbles was measured according to JIS K3362. (3) Foamability (b) Obtained by adding 5% and 2.5% aqueous emulsion (absolute dry weight basis) and sulfuric acid band to 1% aqueous slurry of pulp (L-BKP), respectively. 1 liter of the aqueous liquid was placed in a device of JIS K 3362, and the contents were circulated by a pump for 10 minutes (8 liters / minute),
The circulation was stopped and the height (mm) of bubbles was measured.

Reference Example 1 1800 parts of tall oil rosin was heated and melted, and 2.7 parts of p-toluenesulfonic acid monohydrate was added as a catalyst while stirring at 165 ° C. Then, 118 parts of a 37% aqueous formaldehyde solution was added at 160 to 170 ° C. over 90 minutes. The mixture was stirred at the same temperature for 1 hour to obtain formaldehyde-modified rosin. To this modified rosin, 1200 parts of gum rosin was further added, and the mixture was stirred and mixed at 175 ° C. for 1 hour. 2950 parts of the mixture and 177 parts of fumaric acid were melted by heating and reacted at 200 ° C. for 3 hours to give an acid value of 203,
A rosin substance (1) having a softening point (ring and ball method) of 103.5 ° C. was obtained.

Reference Example 2 1000 parts of gum rosin and 190 parts of fumaric acid were heated and melted to 200 ° C. and reacted at the same temperature for 4 hours to obtain a reinforced rosin having an acid value of 286 and a softening point of 138.5 ° C. 550 parts of enhanced rosin and gum rosin 500 obtained above
Parts were heated to 170 ° C. and mixed for 30 minutes to obtain a rosin substance (2).

Reference Example 3 1000 parts of gum rosin was heated and melted at 165 ° C., and 0.95 part of p-toluenesulfonic acid monohydrate was added as a catalyst while stirring. Then, 54 parts of a 37% formaldehyde aqueous solution was added over 90 minutes at 160 to 170 ° C. The mixture was stirred at the same temperature for 1 hour to obtain formaldehyde-modified rosin. The temperature was raised to 200 ° C. and the reaction was carried out at the same temperature for 4 hours. 90 parts of fumaric acid was added to this, and 2
After reacting at 00 ° C for 3 hours, acid value 230, softening point 125
A rosin substance (3) of ℃ was obtained.

Reference Example 4 1000 parts of gum rosin and 80 parts of glycerin (equivalent ratio (-OH / -COOH) = 0.86) were charged, heated to 250 ° C. under a nitrogen stream, and esterified at the same temperature for 12 hours. , Acid value 32, rosin substance with softening point 86 ℃ (4)
Got

Reference Example 5 A rosin substance having an acid value of 126 and a softening point of 79 ° C. was prepared in the same manner as in Reference Example 4 except that the amount of glycerin charged in Reference Example 4 was changed to 20 parts (equivalent ratio = 0.22). 5) was obtained.

Reference Example 6 The procedure of Reference Example 4 was repeated except that the amount of glycerin charged was changed to 120 parts (equivalent ratio = 1.29).
A rosin substance (6) having an acid value of 8 and a softening point of 88 ° C. was obtained.

Reference Example 7 The rosin substance (4) obtained in Reference Example 4 was kept at 180 ° C. after completion of esterification, 160 parts of maleic anhydride was added, and 2
Addition reaction is carried out at 10 ° C for 3 hours, acid value 185, softening point 1
A 22 ° C. rosin material (7) was obtained.

Reference Example 8 The rosin substance (5) obtained in Reference Example 5 was kept at 180 ° C. after completion of esterification, and 90 parts of maleic anhydride was added to
Addition reaction is performed at 0 ° C for 2 hours to give an acid value of 90 and a softening point of 210.
A rosin substance (8) of ℃ was obtained.

Reference Example 9 The rosin substance (6) obtained in Reference Example 6 was maintained at 180 ° C. after completion of esterification, and 90 parts of maleic anhydride was added to
Addition reaction is carried out at 0 ° C. for 2 hours to give an acid value of 90 and a softening point of 115.
A rosin substance (9) of ℃ was obtained.

Examples 1 to 6 In a flask equipped with a stirrer and a thermometer, 100 parts of the rosin substance (1) of Reference Example 1 was charged and melted by heating.
At 0 ° C., 20 parts of a 20% aqueous solution of the compound shown in Table 1 as a dispersant was added to the molten rosin substance in about 3 minutes with stirring. At this point a considerable amount of water had evaporated and the temperature had dropped to 93 ° C. Then, 20 parts of hot water (95 ° C.) was added to produce a creamy water-in-oil emulsion. While stirring the emulsion vigorously, it was further mixed with hot water (90
When 70 parts of (.degree. C.) was added over 1 minute, phase inversion occurred and an oil-in-water emulsion was formed. This was rapidly cooled from the outside to lower the temperature to 30 ° C. and then put into a glass bottle through a 100-mesh wire net. No solidified material was found on the wire mesh,
The rosin substance contained in the obtained aqueous emulsion had substantially the same weight (yield 98% or more) as the rosin substance used. Table 2 shows the properties of the obtained emulsion.

[0039]

[Table 1] In Table 1, EO represents ethylene oxide, PO represents propylene oxide, and BO represents butylene oxide.

Comparative Example 1 The same as Example 1 except that the sodium salt of polyoxyethylene (average polymerization degree 10) nonylphenyl ether sulfuric acid half ester was used in place of the compound shown in Table 1 as the dispersant. An aqueous emulsion was obtained in the same manner. Table 2 shows the properties of the obtained emulsion.

Comparative Example 2 The same procedure as in Example 1 was repeated except that the sodium salt of polyoxyethylene (average degree of polymerization: 9) nonylphenyl ether sulfosuccinic acid half ester was used as the dispersant in place of the compound shown in Table 1. To obtain an aqueous emulsion.
Table 2 shows the properties of the obtained emulsion.

[0042]

[Table 2]

From Table 2 above, according to the method of the present invention, based on the use of the specific dispersant represented by the general formula 1, the mechanical stability is superior to the use of the known dispersant, Moreover, it was found that an aqueous emulsion having a considerably low foaming property can be obtained.

<Practical Test 1> When the aqueous emulsions obtained in Examples 1 to 6 and Comparative Examples 1 and 2 were used as a sizing agent for papermaking, the sizing degree (seconds) of the formed paper was measured by the Steckigt method (JIS P8122). ). That is, 0.2% based on the dry weight of pulp with a beating degree of 30 ° SR.
Or 0.5% aqueous emulsion and then 2.5% sulfuric acid band were added in the order of chemicals and dispersed uniformly,
Paper was prepared at pH 4.5 using a TAPPI standard sheet machine so that the weight was 60 ± 1 g / cm ³ . This was dehydrated at a pressure of 5 kg / cm ² for 3 minutes and then dried at 100 ° C. for 1 minute.
H. The size effect was measured after conditioning the humidity for 24 hours. The results are shown in Table 3.

<Practical test 2> Pulp having a beating degree of 30 ° SR (newspaper waste paper, containing 3% of calcium carbonate) was used as a 1% aqueous slurry, and 0.5% based on the dry weight of pulp.
% Aqueous emulsion, then 1.0% sulfuric acid band in order of chemicals to diffuse evenly, then paper pH
Paper was made at 6.5 in the same manner as in practical test 1, and the size effect was measured. The results are shown in Table 3.

[0046]

[Table 3]

From Table 3 above, the aqueous emulsion obtained by the method of the present invention not only exhibits an excellent size effect under ordinary acidic papermaking conditions of pH 4.5, but also has a pH of 6.
It can be seen that even under a weakly acidic papermaking condition such as No. 5, an excellent size effect which cannot be obtained by the aqueous emulsion obtained by using the known dispersant is exhibited.

Examples 7 to 14 A stable aqueous emulsion was obtained by the same procedure as in Example 1 except that the rosin substance (1) was replaced with the rosin substances (2) to (9) shown in Table 4. The yield is almost 100%, and all emulsions have a particle size of 0.20 to 0.35.
It was μ. The size effect of each of the resulting emulsions was similarly measured. The results are shown in Table 4.

[0049]

[Table 4]

[0050]

When the aqueous emulsion obtained according to the present invention is used as a sizing agent for papermaking, an excellent sizing effect can be imparted to papermaking in a wide range of papermaking pH range. Further, since it has excellent dilution stability, it can be sufficiently diluted even with water from rivers, waterworks, wells, etc. and is well dispersed in an aqueous dispersion of pulp. Moreover, the diluted solution is stable for a long time.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display part D21H 17/62

Claims (1)

[Claims] 1. When a rosin substance is dispersed in water in the presence of a dispersant to prepare an aqueous emulsion of a rosin substance, the dispersant is represented by the general formula: (However, R ¹ is an alkyl group, alkenyl group, or aralkyl group having 4 to 18 carbon atoms, R ² is hydrogen or an alkyl group, alkenyl group, or aralkyl group having 4 to 18 carbon atoms, and R ³ is hydrogen or a methyl group. , A has 2 to 2 carbon atoms
4 alkylene group or substituted alkylene group, n is 1
To an integer of 200, and M is one or more compounds represented by monovalent cations), and a method for producing an aqueous emulsion of a rosin substance.