JPH07224135A - Lignin condensate and dispersant therefrom - Google Patents

Abstract

PURPOSE:To obtain a lignin condensate which provides a dispersant useful for dyes, cement, inorganic and organic pigments, gypsum, coal, aqueous slurry, agrochemicals and ceramics by reacting lignin and amino acid with formaldehyde under aqueous conditions at a specific ratio. CONSTITUTION:(A) 100 pts.wt. of lignin such as KP lignin or its sulfomethylated derivative or a ligninsulfonic acid and (B) 5 to 30 pts.wt. of an amino acid such as glycine, glutamic acid or imino-diacetic acid are mixed in water. The aqueous solution or suspension is adjusted in pH to 4-11, preferably 7 to 10 and heated up to 50 to 120 deg.C, then (C) 1 to 30 pts.wt. of formaldehyde (for example, formation) is allowed to react with the resultant product in a reaction concentration of 10 to 50% for 1 to 30 hours. By this method, a lignin condensate is obtained.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an industrial dispersant. More specifically, it relates to a dispersant useful for dyes, cements, inorganic and organic pigments, gypsum, coal / water slurries, agricultural chemicals, ceramics and the like.

[0002]

2. Description of the Related Art Conventionally, as a lignin-based dispersant, KP lignin purified from kraft pulp effluent is sulfomethylated with sulfite and formaldehyde, or obtained from sulfite pulp effluent. Known lignin sulfonic acid, its partially desulfonated product, and ultrafiltered and purified products are known.Dyes, cements, inorganic and organic pigments, gypsum, coal
It is used in a wide range of fields such as water slurries, agricultural chemicals, and ceramics. However, the conventionally known lignin-based dispersants have insufficient dispersibility when used as a dispersant for dyes, for example, so that lignin remains on the dyed cloth and colors the dyed cloth (hereinafter abbreviated as stain). It has the drawback of Further, when used as a dispersant for a cement composition that is used in large amounts in the field of civil engineering and construction, it has the disadvantage that the pot life is limited due to insufficient stability of the fluidity of the cement composition over time. Have

Therefore, the present inventors have improved the affinity and the adsorptivity by introducing a carboxyl group into lignin rather than using a conventional sulfonic acid type dispersant such as sulfomethylated lignin or lignin sulfonic acid. The lignin-based dispersant, which is superior in dispersibility and dispersion sustainability (stability of fluidity over time) to the lignin-based dispersant, was investigated, and various investigations have been conducted, resulting in the invention. is there.

[0004]

The present invention provides a lignin 100.
Parts by weight and 5 to 50 parts by weight of amino acid were reacted with 1 to 30 parts by weight of formaldehyde under aqueous conditions by a dispersant based on a condensate produced. The lignin and amino acids used in the present invention also include salts thereof. As lignin, in addition to KP lignin purified from kraft pulp effluent, explosive lignin, organosolv lignin, sulfomethylated products of KP lignin, sulfo groups such as lignin sulfonic acid, modified products thereof, and ultrafiltration. It is possible to use processed products,
KP lignin, a sulfomethylated product of KP lignin, lignin sulfonic acid and its partially desulfonated product, and a product purified by ultrafiltration are suitable.

As the amino acid, glycine, glutamic acid, iminodiacetic acid, alanine, aspartic acid, serine, aminobutyric acid, glutathione, aminocaproic acid,
Valine, phenylalanine, methionine, leucine and the like can be used, but glutamic acid, iminodiacetic acid, glycine and the like are preferable. Further, for formaldehyde, formalin (formaldehyde aqueous solution) is preferably used. In addition, acetaldehyde, paraformaldehyde, hexamethylenetetramine and the like can also be used.

The dispersant of the present invention can be obtained by reacting 100 parts by weight of lignin and 5 to 50 parts by weight of amino acid with 1 to 30 parts by weight of formaldehyde under an aqueous condition. If it deviates from this range, a large amount of unreacted substances remain, or the reaction rate of amino acids is too low to show a sufficient effect. Also, usually lignin and amino acids are mixed in water,
The aqueous solution or suspension is stirred, further heated and reacted with formaldehyde. The reaction concentration at that time is 10
-50%, reaction temperature 50-120 ° C, reaction time 1-
30 hours is appropriate. Further, the pH of the aqueous solution or suspension of lignin and amino acid is preferably 4 to 11, and it is desirable to adjust the pH by adding alkali or acid as necessary. A particularly preferred pH is 7 to 10. The alkali and acid used are not particularly limited, but sodium hydroxide, calcium hydroxide, sulfuric acid, etc. are common.

[0007]

EXAMPLES The present invention will be described in more detail with reference to examples, but parts in the examples indicate parts by weight. Example 1 KP lignin 100 parts, glutamic acid 10 parts, water 400
While stirring the parts, a 30 wt% sodium hydroxide aqueous solution is added to adjust the pH to 9. 90 ° C while stirring this solution
The mixture was heated up to 5 parts, and 5 parts of formalin (37% by weight formaldehyde aqueous solution) was added dropwise, followed by reacting under reflux for 20 hours to obtain an aqueous condensate solution of the present invention. The pH of the obtained aqueous solution was 8.6. The KP lignin used was 10% by weight of the hardwood bleached kraft pulp effluent heated to 70 ° C.
After adjusting the pH to 3 with an aqueous sulfuric acid solution, the precipitated lignin was filtered, washed twice with water and purified (hereinafter abbreviated as KPL).

Aqueous condensate solutions of Examples 2 to 19 were obtained in the same manner as in Example 1 except that the amounts of lignin, amino acid and formalin in Example 1 were changed to the parts by weight shown in Table 1. The pH values of the aqueous solution before the reaction and the aqueous solution after the reaction are also shown in Table 1.
As for lignin, Examples 2 to 6 have the same KP as Example 1.
L, Examples 7 to 14 are trade names Vanillex RN (hereinafter abbreviated as VRN), which is a partially desulfonated lignin sulfonic acid manufactured by Nippon Paper Industries, and Examples 15 to 16 are trade names REAX85A (hereinafter, REA) from West Baco. Examples 17 to 19 are ligninsulfonic acid (hereinafter abbreviated as SPL) obtained by subjecting a coniferous sulfite pulp effluent to ultrafiltration treatment to reduce the reducing sugar content to 2% or less. Examples of amino acids are glutamic acid in Examples 2-3, 7-9, and 15-19, glycine in Examples 4-6, and 12-14,
Examples 10 and 11 used iminodiacetic acid.

[0009]

[Table 1]

In order to show the usefulness of the present invention, a dye dispersibility test and a cement dispersibility test of the condensate produced by the examples were conducted. As comparative examples, KPL used in Examples 1 to 6, VRN used in Examples 7 to 14, REA used in Examples 15 to 16 and SPL used in Examples 17 to 19 were used.

1. Dye dispersibility test The stain resistance using the condensate of the example and the dispersibility at high temperature were compared with the lignin of the comparative example. (1) Contamination test A condensate of the example or 600 mg of lignin of the comparative example was dissolved in 200 cc of water and adjusted to pH 5 with an aqueous acetic acid solution, and then water was added to adjust the total amount to 250 cc to obtain a test adjustment solution. After that, 8 g of test cloth (cotton, polyester) is wound around the test holder, charged into a pot together with the adjusting solution, set in a dyeing tester, and dyed at 105 ° C. for 1 hour, and then the test cloth is dried and white. The degree was measured. The obtained results are shown in Tables 2 and 3.

(2) High-Temperature Dispersibility Test 99 g of the dye (Despers Red 60), the condensate of the example, or 94.4 g of the lignin of the comparative example are put in a pot together with 400 cc of glass beads and set in a sand mill. The dye was pulverized to a particle size of 0.8 μm or more to 19% or less and then filtered through two polyester cloths to obtain a disperse dye solution. 1.2 g of this disperse dye solution was collected as a solid content, 200 cc of water was added, and then the pH was adjusted to 5 using an aqueous acetic acid solution. Water was added to bring the total amount to 250 cc to obtain a preparation liquid. 10 g of test cloth (polyester) is wound around a holder for testing and charged into a pot together with an adjusting solution, and set in a dyeing tester at 130 ° C.
After the dyeing operation was performed for 10 minutes, the test cloth was dried at room temperature and the specs condensed on the cloth were visually judged. The obtained results are shown in Tables 2 and 3. Items without specs were marked with O, those with slight specs were marked with Δ, and those with many specs were marked with X.

[0013]

[Table 2]

[0014]

[Table 3]

2. Cement dispersibility test The change with time of the fluidity and the change with time of the amount of entrained air of the mortar to which the condensate was added in Example were compared with those of the mortar to which lignin of Comparative Example was added. (1) Mixing of used materials and mortar The used materials and mortar are 850 g of ordinary Portland cement (specific gravity 3.16) according to JIS R5210.
Kawasuna (Shimane / Kashima = 5/5 mixture, specific gravity 2.57, coarse grain ratio 2.74), 2380 g, and water 500 g. (2) Kneading of mortar Kneading of mortar was performed for 3 minutes using a mortar mixer according to JIS R5201.

(3) Flow measurement Immediately after kneading and after 30 minutes and 60 minutes, the flow of mortar was slump cone (upper inner diameter 50 mm, lower inner diameter 100).
m and a height of 150 mm). The addition rate of the dispersant was adjusted so that the flow immediately after kneading was 200 ± 5 mm. The obtained results are shown in Tables 4 and 5. The addition rate is shown as% by weight of cement. (4) Measurement of air content The air content of the mortar immediately after kneading and after 30 minutes and 60 minutes was measured by the gravimetric method using a container having a capacity of 400 cc according to JIS A1116. The results obtained are shown in Table 4,
5 shows. (5) Change with time After measuring the flow and the amount of air immediately after kneading, the mortar was collected in a mixing pole and allowed to stand for 30 minutes and 60 minutes, and then the flow and the amount of air were measured. The obtained results are shown in Tables 4 and 5.

[0017]

[Table 4]

[0018]

[Table 5]

As is clear from the results of the dye dispersibility test shown in Tables 2 and 3, the condensate of the present invention has a lower staining property on the dyed fabric and an excellent dispersibility at the time of high temperature dyeing than the lignin of the comparative example. . Further, as is clear from the results of the cement dispersibility test in Tables 4 and 5, the condensate of the present invention causes less decrease in the fluidity of the cement composition than the lignin of the comparative example. Further, as compared with the lignin of the comparative example, the same flow is exhibited at a low addition amount, so that the dispersibility is excellent.

[0020]

INDUSTRIAL APPLICABILITY The dispersant of the present invention is useful as a dispersant for dyes, cements, inorganic and organic pigments, gypsum, coal / water slurries, agricultural chemicals, ceramics, etc., but especially when used as a dispersant for dyes. Rarely contaminates dyed fabrics. Further, when used as a dispersant for cement, it exhibits an excellent effect on dispersion durability.

Claims (7)

[Claims] 1. 100 parts by weight of lignin and 5 to 5 amino acids
A condensate produced by reacting 0 part by weight with 1 to 30 parts by weight of formaldehyde under aqueous conditions. 2. A dispersant containing the condensate according to claim 1 as a main component. 3. A dispersant for a dye, which comprises the condensate according to claim 1 as a main component. 4. A dispersant for cement comprising the condensate according to claim 1 as a main component. 5. The dye dispersant according to claim 3, wherein the lignin is KP lignin or a sulfomethylated product of KP lignin. 6. The dispersant for cement according to claim 4, wherein the lignin is lignin sulfonic acid. 7. The dispersant according to any one of claims 2 to 6, wherein the amino acid is glycine, glutamic acid, or iminodiacetic acid.