JPS5831081B2 - Method for producing printing paste for reactive dyes by solid-phase reaction - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the use of cellulose IJ as a printing paste for reactive dyes.
'=r-Relating to a method for producing sodium phosphate (hereinafter, cellulose sodium glycolate is abbreviated as NaCMC).

NaCMC is produced by reacting cellulose, caustic soda, sodium monochloroacetate, and water, and various production methods have been developed, and demand for it as a printing paste has increased in recent years.

However, it is almost impossible to put it into practical use when printing reactive dyes due to poor desizing properties, and even today, sodium alginate is almost the only printing paste used for reactive dyes. It is used like something.

The present inventor conducted research to develop a method for producing NaCMC, which has excellent desizing properties when used as a thickening agent for printing reactive dyes, and completed the present invention.

That is, the present invention is a method for producing NaCMC by reacting cellulose, caustic soda, sodium monochloroacetate, and water, which includes a step of adding bleaching powder to the reaction product and performing a solid phase reaction using a small amount of water as a medium. It is characterized in that the relative viscosity of a 1% aqueous solution of the reaction product NaCMC at 25° C. is 5.0 or less.

The reaction product of the solid phase reaction is swollen crude NaCMC1 or purified NaCM containing salts such as common salt, sodium glycolate, caustic soda, and soda carbonate, and residual free alkali.
Any of C may be used, and the purpose can also be achieved by mixing cellulose and caustic soda at the beginning of the production process, aging them under severe conditions, and then etherifying them to carry out the solid phase reaction of the present invention.

Now, in the past, there have been almost no noteworthy research reports regarding the improvement of the printing suitability of reactive dyes of NaCMC, but in recent years, the following 2.3 studies have been made related to the oxidation of NaCMC by bleaching powder by the present inventor. There is a literature on this.

Namely (1) M. Kamel et al. Tex. Res. J. 4
15.450-4 1971: AmericanD
yestuff Reporter 64 (3)
, 22.24-51975, (2) A, K, Nar
Kar et al., Tex, Dyer & Printer, 9
．． 1.41-4 1975, (3) Masamoto Takato et al., Japanese Patent Application Publication, 1982-1876, etc.

Methods (1) and (2) above involve oxidation using an aqueous Na0C1 solution, but since both of these oxidation systems contain a large amount of water, NaCMC dissolves in water to form a viscous paste liquid and is oxidized. All reactions are carried out in a liquid phase, and method (3) does not use water as a medium, but uses particularly high concentration (80% or more) alcohol.

Note that the above document (3) states that when only water is used as a medium, the bonds within the CMC molecules are broken by an oxidizing agent, but these clearly indicate that a large amount of water is present. It describes the phenomenon of the so-called liquid phase reaction, and does not relate to the solid phase reaction of the present invention in which a small amount of water is present, but rather describes the oxidation reaction conditions and the printing suitability of the product, which are the most important industrially. There is no description of the interrelationship between the two, and therefore, the most important issue mentioned above is still completely unclear from any past literature.

However, the method of the present invention requires only a small amount of water to be used as the reaction medium, and a viscous paste solution of NaCMC as described in (1) and (2) above. It is not a phase oxidation reaction but a solid phase oxidation reaction, and (
It is not a heterogeneous oxidation reaction using a unique reaction medium as in 3), and the degree of oxidation necessary for the desired desizing property was clarified from the viewpoint of the viscosity of the oxide stone product as a result of systematic research. This method is essentially completely different from the methods described in all of the above-mentioned documents, is advantageous from a pharmacoeconomic standpoint, and is the simplest method for industrial application.

To describe the content of the present invention in more detail, NaCMC, which is normally produced by applying a solid-phase oxidation reaction using bleaching powder to a general NaCMC production method, is used as a printing paste of a reactive dye that has particularly excellent desizing properties. It can be reformed into raw materials.

Also, the amount of bleaching powder to be added is 25% of NaCMC as described above.
An essential condition is to use an amount such that the relative viscosity of a 1% aqueous solution at °C is 5.0 or less.

More specifically, it is a method of oxidizing NaCMC using bleaching powder with an amount of 1% to 5% of available chlorine.

In addition, the solid phase reaction is performed at the final stage of the normal NaCMC production, for the swollen crude cellulose sodium glycolate containing salts such as common salt, sodium glycolate, caustic soda, and soda carbonate, and residual free alkali, or in addition, The purpose can be achieved by applying this to any NaCMC after purification.

Furthermore, if the alkali cellulose is aged under particularly severe conditions in the early stages of NaCMC production, the amount of bleaching powder required can be reduced to a considerable extent (for example, by half).

However, no matter how severe the aging process is to reduce the viscosity of the product to a predetermined viscosity or less, the desired printing suitability cannot be obtained, and the desired printing paste production method cannot be achieved. , solid phase oxidation by bleaching is an absolute must.

The features of the present invention can be summarized as follows.

(2) As mentioned above, from the standpoint of desizing properties of reactive dyes as printing pastes, the relative viscosity of the aqueous solution of the product after oxidation reaction is 1.0% concentration as NaCMC, 25°C.
It has been confirmed and investigated that the most important and essential condition is to reduce the value to 5.0 or less.

2. Relatively inexpensive bleaching powder (hypochlorous acid Ca) as an oxidizing agent
salt).

This oxidation reaction takes place at room temperature, but bleached powder is approximately 35°C.
Self-decomposition hardly occurs at room temperature below, so all bleached powder used is used in the reaction.

Therefore, the viscosity reduction caused by the aqueous bleaching powder solution of NaCMC is actually more closely related to the amount of bleaching powder used for NaCMC than other conditions.

Therefore, the above-mentioned viscosity reduction can be easily controlled mainly by bleaching alone.

3. Do not use an organic solvent or the like as a medium for the oxidation reaction, but use a small amount of water to carry out the solid phase reaction.

Therefore, the reaction can be completed in the state of wet fine powder or swollen fibers like bread crumbs, so it can be put to practical use as it is.

The oxidation reaction conditions are not limited to pH, etc., and can generally be completed at room temperature in a short time of 2 to 3 hours.

Next, the present invention will be explained based on Examples and Comparative Examples.

The standard test method for printing suitability for the purposes of these Examples and Comparative Examples was to use 5% reactive dye Remazol Black B (manufactured by Hoechst) as color paste, and 60% base paste (depending on the viscosity of the sample). Rayon and cotton fabrics were screen-printed using a composition of 5% urea, 1% soda carbonate, and 29% water (total 100%), prepared at the respective concentrations listed, and air-dried under the same conditions. After steaming and using the standard method (air-dried), the dyed fabric is immersed in water at a room temperature of 10 to 25°C for about 15 minutes, and it takes about 20 minutes to gently shake the dyed fabric up and down and left and right a total of 320 times. The desizing properties, texture, hue, etc. of the dyed fabrics after washing were compared visually and by hand.

There was almost no difference in hue or anything else, so
All evaluations of suitability for printing were made based solely on desizing properties.

Printing results marked with an x mark indicate poor quality, a mark with an ○ mark indicates an excellent quality, a mark D indicates an intermediate level between ○ and an x mark, and a printing result with two marks indicates an intermediate level between the two.

Printing results marked with a circle indicate that the desizing property is at least equivalent to or better than that of sodium alginate, which was tested in parallel as a control, and that there is no difference in color tone or other general printing effects. The judgment was based on the absence of *.

Examples, Comparative Example 1 Using three types of purified NaCMC powders with different manufacturing methods and varying the amount of bleaching powder added, a solid phase reaction was performed at room temperature for 2 hours.

For this oxidation, a bleached powder aqueous solution with an available chlorine concentration of 29.2 g/l was used.

NaCMC powder /161-5 is obtained by monochlorosodium acetate method-sulfuric acid purification method, scraps 6-11 are obtained by monochlorosodium acetate method-methanol purification method, 412-1
5 is based on the Arcel method-methanol purification method,
The average degree of etherification (DS) of each is 0.73.0.
62.0.92.

Table 1 shows the solid phase oxidation conditions, the relative viscosity of the NaCMC produced, and the printing test results.

The above table shows that there is a clear tendency for printing performance to improve as the viscosity of the paste decreases.

And for the preferred viscosity reduction, the viscosity of the product (1%
, 25°C) of 6.5 is still insufficient, and in this experimental example, a very low viscosity of 4.0 was used to achieve excellent desizing when used for the first time for printing with the target reactive dye. It can be seen that a paste with properties can be obtained.

Although the DS of purified NaCMC used in the present example and comparative example is slightly different, Table 1 shows that in both cases, it is a kind of significant critical phenomenon that occurs with the viscosity of 5 as the inflection point. I can say that.

This is why, in the present invention, the viscosity of the product can be defined as 1% and 5.0 or less at 25° C. as suitable reaction conditions for solid-phase oxidation using bleaching powder.

Example, Comparative Example 2 For two types of production methods, bleaching powder (same conditions as Example and Comparative Example 1) was added at the end of each reaction to perform solid phase oxidation, resulting in a crude product containing salts, free alkalis, etc. The desizing properties of the purified products obtained by purifying methanol were investigated.

Solid phase oxidation conditions and results are shown in Table 2.

In the table, /i61-5 is the monochloroacetic acid soda method,
1.4 mol of sodium monochloroacetate is used per mol of C6 basic molecule of cellulose, and 1.7 mol of sodium monochloroacetate is used per mol of C6 basic molecule of cellulose in the Arcel method for //66 to 9. there was.

In each case, the solid phase oxidation described above was performed at the end of the reaction.

According to Table 2, the viscosity of the product decreases in accordance with the amount added, and the preferred viscosity for printing suitability is 6 to 70 ml of a 1% aqueous solution of pure NaCMC after methanol purification of the crude product at 25°C. The degree of oxidation is still clearly insufficient, and the condition for ensuring excellent desizing properties requires oxidation to a degree that the viscosity is 5 or less.

Also, when comparing the desizing properties of the crude product and the purified product, the latter is seen to be somewhat superior, but in general, regardless of whether it is crude or purified, the desizing properties are extremely excellent. Therefore, it is generally not necessary to purify NaCMC after bleaching and oxidation.

Example, Comparative Example 3 The effect of the present invention was investigated when the alkali cellulose was aged under particularly harsh conditions at the beginning of the NaCMC manufacturing process.

The results are shown in Table 3. In Experiment/161-5, when only the alkali cellulose was aged and no bleaching treatment was performed,
/f66-9 indicates the case where aging was performed and bleaching process was also performed.

/161-5, as the degree of ripening increases, Na
Although the relative viscosity of CMC is reduced, no matter how much it is reduced, the desizing properties are not improved.

However, as shown in /166-9, if severe aging and bleaching treatment are combined, the amount of bleaching paste can be reduced by a considerable amount.

Claims (1)

[Claims] 1. In a method for producing cellulose sodium glycolate by reacting cellulose, caustic soda, sodium monochloroacetate, and water, the reaction product is subjected to solid-phase oxidation with bleaching powder using a small amount of water as a medium. A method for producing a printing paste for reactive dyes by a solid-phase reaction, characterized in that the relative viscosity of a 1% aqueous solution of sodium cellulose glycolate at 25° C. after the treatment is 5.0 or less. . 2. The manufacturing method according to claim 1, wherein the reaction product is swollen crude cellulose sodium glycolate. 3. The manufacturing method according to claim 1, wherein the reaction product is refined edible fibers and sodium glycolate. 4. The method of reacting cellulose, caustic soda, sodium monochloroacetate, and water, which includes the step of first mixing cellulose and caustic soda, aging them under harsh conditions, and then etherifying them. Method.