JPH08209070A - Production of pale colored tall oil rosin ester - Google Patents

Abstract

PURPOSE: To obtain the subject compound at a low cost, capable of markedly improving an initial color and smelling thereof by using a new method for treating a tall oil rosin with a specific clay, and then esterifying with alcohol in the presence of a specific compound without using any special technique. CONSTITUTION: This method for producing a pale colored tall oil rosin ester comprises first adsorption treating a tall oil rosin by an acid clay and/or an activated clay, preferably by a mineral acid treated activated clay and then removing a high boiling point substance by a distillation, and esterifying the obtained purified tall oil rosin with an alcohol (preferably pentaerythritol) in the presence of the compound of the formula (A is a substituted aromatic ring such as benzene ring, naphthalene ring, etc.; R is H, a 1-20C alkyl, etc.; (n) is 1-3; (m), (x) are each 1-4; (y) is 0-2; (p) is 0 10) [preferably 4,4'-bis(6-t- butylmethacresol)sulfide] to obtain the objective compound. Furthermore, based on the weight of the rosin, 1-5wt.% acid clay and/or activated clay and 0.01-5wt.% compound of the formula are preferably used.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing light oil and odor-improved tall oil rosin ester.

[0002]

[Prior Art and its Problems] Rosin ester has been used in the past for adhesive resin (tackifier), ink resin,
It is used in a wide range of applications such as traffic paint resins, various rubber and plastic modifiers. The raw material rosin resources are gum rosin, wood rosin,
There are three types of tall oil rosin, and of these, tall oil rosin, which is a by-product of the paper pulp manufacturing process, has a stable supply and can be said to be the most industrially available resource. In various uses of rosin esters, color tone is an extremely important factor together with acid value and softening point, and generally, the lighter the color resin, the higher the industrial value thereof. When the rosin is reacted with alcohol to form an ester, the rosin is heated at a high temperature, so that a potential coloring component contained in the rosin is susceptible to oxidation or thermal denaturation, resulting in deterioration of color tone.
Nos. 80,012 and 3,780,013 disclose esters of tall oil rosin and pentaerythritol,
It is described that the color is remarkably darker than when gum rosin or wood rosin is used.

In order to remedy such drawbacks, US Pat. No. 3,780,012 discloses a method in which tall oil rosin is treated with paraformaldehyde, high boiling substances are removed by distillation, and then esterification is carried out. However, the obtained ester is still colored yellowish brown, and the effect is not sufficient. Also, JP-A-63-156874 and US Pat. No. 5,162,
No. 496 describes a method for producing a light-colored rosin ester by using phosphinic acid and a phosphoric acid ester in combination with phenol sulfide, but it is still yellow and not satisfactory as a light-colored rosin ester, and The odor characteristic of oil rosin still remains. Further, a method for producing a rosin ester having improved color tone, odor and stability by carrying out operations such as disproportionation reaction with metal catalyst, dehydrogenation reaction and hydrogenation is disclosed in JP-A-5-171112. As described in JP-A-5-279631, these methods require many steps and are not economically disadvantageous. In addition, when the starting material is tall oil rosin, the sulfur contained in the rosin is However, since it acts as a catalyst poison to a metal catalyst such as palladium which is a disproportionation and dehydrogenation catalyst, its application to tall oil rosin is practically difficult. As described above, none of the methods known so far are sufficient to improve the initial color tone and odor of tall oil rosin ester, and it is desired to develop a more sophisticated new method. There is.

[0004]

In view of the above situation, the present inventors have proposed a method for inexpensively producing tall oil rosin ester having a significantly improved initial color tone and odor, without using any special technique. We have conducted intensive studies for the purpose of developing.

[0005]

[Means for Solving the Problems] When the light-colored tall oil rosin ester is produced, the present inventors remove the coloring component contained in the raw tall oil rosin and, at the same time, improve the color tone of the esterification reaction. We have come to recognize that maintenance and improvement are important.

Regarding the maintenance and improvement of the color tone in the esterification process, in Japanese Patent Publication No. 2-52943, a light color is obtained by coexisting a specific organic sulfur compound when esterifying a rosin that has been purified by distillation with an alcohol. It is described that it is possible to produce rosin esters.

Therefore, the present inventors have found that in the removal of coloring components, not only coloring components such as high molecular weight substances and unsaponifiable compounds but also coloring components specific to tall oil rosin are present in the raw material tall oil rosin, Focusing on the fact that this colored component is difficult to remove only by distillation operation, and that the main colored component and sublimable odorous component are selectively adsorbed and decomposed by specific clay, the results show that the initial color tone We have succeeded in developing a new method for producing tall oil rosin ester that dramatically improves odor.

That is, the present invention is a method for producing a tall oil rosin ester having a light color and improved odor, wherein tall oil rosin is subjected to adsorption treatment with acid clay and / or activated clay, and then distilled to a high boiling point. Remove things,
Then, the purified tall oil rosin is added to the reaction system by one or two selected from the group of compounds represented by the following general formula (1).
A method for producing a light-colored rosin ester, which comprises esterifying with an alcohol in the presence of at least one compound. General formula (1)

Embedded image In the formula, A is a substituted aromatic ring such as a benzene ring or naphthalene ring, R is hydrogen, or a C1 to C20 alkyl group or a cycloalkyl group, n is an integer of 1 to 3, and m is 1
To an integer of 4, x is an integer of 1 to 4, y is an integer of 0 to 2, p
Represents an integer of 0 to 10. Therefore, when the tall oil rosin is purified by either the clay treatment or the distillation operation or when the organic sulfur compound represented by the compound (1) does not coexist during the esterification, it is an object of the present invention. Tall oil rosin esters with light color and improved odor cannot be produced at all.

In the present invention, tall oil rosin used is abietic acid, parastophosphoric acid, neoabietic acid,
It is a resin mixture containing a resin acid such as pimaric acid, isopimaric acid, and dehydroabietic acid as a main component.

Next, as the acid clay and / or activated clay used in the present invention, the acid clay is Al ₂ O ₃ .4.
This is a montmorillonite clay having the general formula of SiO ₂ n H ₂ O, which contains Al ₂ O ₃ and SiO ₂ as main components, and also contains a small amount of Fe ₂ O ₃ , CaO and MgO. Furthermore, the activated clay obtained by treating the clay with a mineral acid such as sulfuric acid has a large specific surface area and a large adsorption capacity. In order to further improve the color tone, the mineral acid-treated activated clay is preferable. In the adsorption step, it is suitable to add 0.1 to 10% of acidic clay or activated clay based on the weight of rosin, but usually 1 to 5% is preferable. If the addition amount is too low, the coloring component cannot be completely removed and the color tone is not sufficiently improved.On the contrary, if the addition amount is too high, the resin acid may be adsorbed to reduce the yield or the resin may be decomposed due to excess acid. is there. The temperature of the rosin at the time of addition is not particularly limited, but usually 250 ° C. or lower is suitable. Further, the adsorption treatment may be carried out as a solution by dissolving tall oil rosin in a good solvent such as toluene or xylene.

Distillation is usually performed at a pressure of 50 mmHg or less for 20 times.
It is carried out at a still temperature of 0 to 300 ° C., and methods such as ordinary simple distillation, thin film distillation, and rectification are applied. Under ordinary distillation conditions, an initial fraction of 2 to 15% by weight based on the charged rosin is obtained. As a high molecular weight substance, 2 to 15% by weight of pitch is removed.

In this manner, the raw material tall rosin is purified by the adsorption step and the distillation step using the acid clay and / or activated clay. The adsorption step and the distillation step may be carried out in any order, but since activated clay has a function of decomposing a coloring component, it is desirable to carry out an adsorption treatment and then distill.

Alcohols used in the present invention include monohydric alcohols such as n-octyl alcohol, 2-ethylhexyl alcohol, decyl alcohol, lauryl alcohol and stearyl alcohol, ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, Dihydric alcohols such as dipropylene glycol, polypropylene glycol and neopentyl glycol, trihydric alcohols such as glycerin and trimethylolpropane, tetrahydric alcohols such as pentaerythritol and diglycerin, and hexahydric alcohols such as dipentaerythritol and sorbitol. Alcohol. Of these, pentaerythritol is particularly preferable from the viewpoints of lightening effect and economical efficiency. The esterification reaction is performed by a known method, that is, by heating rosin and alcohol to 200 to 300 ° C. under an atmosphere of an inert gas and removing the produced water out of the system. The excess ratio of alcohol is arbitrary, but generally 0.5 to
1.5 is preferred. Further, in the esterification, known catalysts such as phosphoric acid, p-toluenesulfonic acid, lithium hydroxide, calcium hydroxide, magnesium oxide, zinc oxide and calcium oxide can be used to accelerate the reaction. In the esterification reaction, 0.01 to 5% by weight of the compound represented by the general formula (1) based on the weight of rosin is present in the reaction system.

The above general formula (1) used in the present invention
Examples of the compound represented by the following include 4,4 ′ especially in the esterification reaction of tall rosin with alcohol (pentaerythritol).
-Bis (6-t-butylmetacresol) sulfide (Santonox manufactured by Monsanto), t-amylphenol disulfide oligomer (VULTAC manufactured by Pennwalt Corp.)
2), nonylphenol disulfide oligomer (Ethyl
It has been found preferable to use Corp. ETHANOX 323). Examples of the compound represented by the general formula (1) that is allowed to coexist in the reaction system during the esterification reaction include 4,4′-bis (phenol) sulfide 4,4′-bis (phenol) sulfoxide 4,4 ′ -Bis (phenol) sulfone 4,4'-bis (phenol) thiol sulfinate 4,4'-bis (phenol) thiolsulfonate 2,2'-bis (p-cresol) sulfide 2,2'-bis (p-cresol) Sulfoxide 2,2'-bis (p-cresol) sulfone 2,2'-bis (pt-butylphenol) sulfide 2,2'-bis (pt-butylphenol) sulfoxide 2,2'-bis (pt-butylphenol) sulfone 4,4'-bis (6-t-Butylmetacresol) sulfide 4,4'-bis (6-t-Butylmetacresol) sulfoxide 4,4'-bis (6-t-butylmetacresol) sulfide 4,4'- Sus (6-t-butyl orthocresol) sulfoxide 4,4'-bis (6-t-butyl orthocresol) sulfone 4,4'-bis (6-t-butyl orthocresol) sulfone 4,4'-bis (resorcinol) sulfide 4,4'-bis (resorcinol) sulfoxide 4,4'-bis (resorcinol) sulfone 1,1'-bis (β-naphthol) sulfide 1,1'-bis (β-naphthol) sulfoxide 1,1'-bis (β-naphthol) Sulfone 4,4'-bis (α-naphthol) sulfide 4,4'-bis (α-naphthol) sulfoxide 4,4'-bis (α-naphthol) sulfone t-amylphenol disulfide oligomer Nonylphenol disulfide oligomer p-cresol and thionyl chloride Examples include polysulfoxide obtained by reacting A compound in which the bonded hydroxyl group is sterically hindered is preferable, and a sulfide is preferable as the organic sulfur compound. Hereinafter, these organic sulfur compounds will be referred to as lightening agents.
The above-mentioned lightening agent can be added in an amount of 0.01 to 5% by weight with respect to the refined tall oil rosin, but in consideration of the lightening effect and economical efficiency, the addition of 0.05 to 1% by weight is particularly preferable. preferable. The reason why the light-coloring agent is allowed to coexist in the esterification reaction is because of the fact that the disproportionation reaction and the esterification reaction of rosin proceed at almost the same temperature. This is due to the purpose of promoting the leveling reaction. However, even if the light-coloring agent is added at the final stage of the esterification reaction, the effect of improving the color tone of the resulting rosin ester may not be as good as expected, and in many cases it is preferable to add it at the early stage of the esterification reaction.

When a high degree of stability is required for the rosin ester, a phenolic antioxidant or a phosphite stabilizer may be used in combination.

The tall oil rosin ester obtained by the method of the present invention has a light color and improved odor that cannot be considered from the conventional fixing concept of tall oil rosin ester, and is a pressure-sensitive adhesive or hot melt adhesive. , Ink resins, traffic paint resins, sealing materials, heat-sealable plastics, etc. to improve the quality and value of raw materials.

[0017]

INDUSTRIAL APPLICABILITY The tall oil rosin ester obtained according to the present invention is remarkably improved in color tone and odor as compared with conventionally known ones, and can be economically provided at a low price.

[0018]

EXAMPLES The present invention will now be described in detail with reference to examples. The number of colors is a Gardner colorimeter, and the softening point is a value measured by a ring and ball method (JIS K-5902).

(Example 1) (1) Treatment of rosin with activated clay In a 2 L glass reaction vessel equipped with a thermometer, a stirrer, an exhaust pipe and a nitrogen introducing pipe, an acid value of 169.8 and a softening point of 81.5.
1,200 g of tall oil rosin (Harthol RX, Harima Kasei Co., Ltd.) having a color number of 6 and a color number of 6 was charged, melted under a nitrogen stream and kept at 180 ° C., and activated clay (trade name: Galleon Earth Mizusawa Chemical Industry ( 36 g) was added and stirred for 30 minutes. Then, the activated clay was separated by filtration to obtain a rosin having the representative physical properties shown in Table 1. (2) Distillation of Rosin 600 g of the rosin obtained in Example 1 (1) was charged into a 1 L volume distillation flask equipped with a thermometer and an air-cooled tube, the rosin was melted under a nitrogen stream, and vacuum distillation was performed at a pressure of 3 mmHg. went. Table 1 shows representative physical properties of each fraction. (3) Esterification 500m equipped with a thermometer, stirrer, exhaust pipe, nitrogen introduction pipe
The main distillate 2 described in Example 1 of Table 1 in an L glass reaction vessel.
50 g was charged and rosin was melted under a nitrogen stream. 20
At 0 ° C., 31.4 g of pentaerythritol and 1 g of nonylphenol disulfide oligomer (trade name: ETHANOX 323, Ethyl Corp.) as a lightening agent were added, and the temperature was raised to 275 ° C. and reacted at the same temperature for 12 hours. The obtained rosin ester has a good color tone as shown in Table 2,
The odor during heating was also improved.

(Example 2) (1) Adsorption treatment with activated clay The treatment was carried out according to the procedure described in Example 1 except that the amount of activated clay was reduced to 12 g. (2) Distillation Distillation was carried out according to Example 1 using the rosin obtained in Example 2 (1). Table 1 shows typical physical properties of rosin treated with clay and each fraction. (3) Esterification Using the main distillate described in Example 2 of Table 1, esterification was carried out according to Example 1 to obtain a rosin ester with a light color and improved odor as shown in Table 2. .

(Example 3) (1) Adsorption treatment with activated clay Example 1 was repeated except that the amount of activated clay was increased to 60 g.
Treatment was performed according to the procedure described in. (2) Distillation Distillation was carried out according to Example 1 using the rosin obtained in Example 3 (1). Table 1 shows typical physical properties of rosin treated with clay and each fraction. (3) Esterification Using the main distillate described in Example 3 of Table 1, pentaerythritol 31.0 g, t-amylphenol disulfide oligomer as a lightening agent (trade name: Vultac 2, Pennwalt
Esterification was carried out using 1 g of Corp.). The procedure was according to Example 1. The obtained rosin ester was a light color as shown in Table 2 and had almost no tall oil odor when heated.

Example 4 (1) Adsorption treatment with activated clay An acid value of 182.0 obtained by distilling tall oil rosin (Harthol RX, Harima Kasei Co., Ltd.) as a raw material,
Distilled rosin having a softening point of 83.5 ° C. and a color number of 4 was used. The activated clay treatment was performed according to Example 1. (2) Distillation Using the rosin obtained in Example 4 (1), distillation was carried out according to Example 1. Table 1 shows typical physical properties of rosin treated with clay and each fraction. (3) Esterification Esterification was carried out according to Example 1 except that the main distillate described in Example 4 of Table 1 was used and the amount of pentaerythritol added was 30.6 g. A very light-colored rosin ester having a small odor component was obtained.

Table 1 shows typical values of rosin treated with clay and each fraction in the above examples.

[0024]

[Table 1]

(Comparative Example 1) Using the tall oil rosin used in Example 1 as a raw material, an esterification reaction was carried out according to Example 1 without treatment with clay and purification by distillation. However, the amount of pentaerythritol used was 29.6 g. The obtained rosin ester was used in Examples 1 to 4 in terms of color number.
It was much inferior to the above and the removal of tall oil odor was insufficient.

(Comparative Example 2) The distilled tall oil rosin described in Example 4 was used as a raw material, and the esterification reaction was carried out according to Example 1 without treatment with clay or distillation purification. However, the amount of pentaerythritol used was 31.7 g. The obtained rosin ester was inferior in the number of colors as in Examples 1 to 4 as shown in Table 2.

(Comparative Example 3) Using the clay treated with clay of Example 1 in Table 1, the esterification reaction was carried out according to Example 1 without distillation. However, the amount of pentaerythritol used was 29.9 g. The obtained rosin ester had an improved odor, but as shown in Table 2, the number of colors was considerably inferior to those in Examples 1 to 4.

Table 2 shows the typical physical properties of the rosin esters obtained from the above Examples and Comparative Examples.

[0029]

[Table 2]

Compared with the existing tall oil rosin ester, the resins shown in Examples 1 to 4 are not only improved in the number of colors by two stages or more, but also improved the odor peculiar to tall oil rosin. , The value as a rosin ester is greatly increased.

Claims (5)

[Claims] 1. A method for producing a light-colored and odor-improved tall oil rosin ester, which comprises subjecting tall oil rosin to adsorption treatment with acid clay and / or activated clay,
Then, the high-boiling substance is removed by distillation, and the purified tall oil rosin is then added to the reaction system in the presence of one or more compounds selected from the group of compounds represented by the following general formula (1) in the presence of alcohol. A method for producing a light-colored rosin ester, which comprises: General formula (1) In the formula, A is a substituted aromatic ring such as a benzene ring or naphthalene ring, R is hydrogen, or a C1 to C20 alkyl group or a cycloalkyl group, n is an integer of 1 to 3, and m is 1
To an integer of 4, x is an integer of 1 to 4, y is an integer of 0 to 2, p
Represents an integer of 0 to 10. 2. The method according to claim 1, wherein the amount of the acid clay and / or activated clay added to the tall oil rosin is 0.1 to 5% by weight. 3. The method according to claim 1, wherein 0.01 to 5% by weight of the compound represented by the general formula (1) is present based on the weight of rosin. 4. The method of claim 1, wherein the alcohol is pentaerythritol. 5. The use of 4,4′-bis (6-t-butylmetacresol) sulfide, t-amylphenol disulfide oligomer, nonylphenol disulfide oligomer as the compound represented by the general formula (1). the method of.