JP2515402B2 - Aromatic polyamide fiber dyeing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention uses an aromatic polyamide fiber containing a hydrophilic group in the presence of a reducing agent and an alkaline liquid, and a vat dye having a light fastness of 7 or higher. Regarding the method of dyeing.

[Conventional technology]

Aromatic polyamide fibers such as poly (metaphenylene isophthalamide) have various properties such as flame resistance, heat resistance and solvent resistance, and are used in a wide range of fields.

In particular, by taking advantage of its flame resistance and heat resistance, its applications in the bedding, clothing, and interior fields are rapidly expanding. However, since the polymer molecular chain is extremely rigid, it is difficult to dye it by an ordinary method, and it is difficult to obtain a resin having high light fastness with free color combinations by a simple and economical method.

Therefore, various methods for improving dyeability have been proposed so far. For example, JP-B-44-11168 or JP-B-55-8
A method of incorporating a sulfonic acid group, a tertiary amino group, or a quaternary ammonium group into the aromatic polyamide shown in 533, in the polymer molecular chain or at the polymer molecular end, JP-A-58-58
87376, a method using a strongly polar carrier,
Further, there is a method of adding dimethyl sulfoxide, which is disclosed in JP-A-62-268877.

However, these dyeing methods use a highly polar carrier, which is a big problem for the environment, or use a solvent such as dimethylsulfoxide, and the applied dye is also used for an aliphatic polyamide or polyester. Since the disperse or acidic dye is used, the dyeing property can be satisfied to some extent, but the dyed product has a markedly poor light resistance and cannot be put to practical use. Sulfonate-containing aromatic polyamides produced from aromatic diamines, aromatic diacid chlorides, and aromatic diacid chlorides sodium monosulfonate are notable for discoloration due to the heat of dyed products and are used for heat-resistant applications. Is difficult.

On the other hand, the vat dye used in the basic dyeing shown in Japanese Examined Patent Publication No. 51-45688 has good light resistance, but since it is a basic dyeing, it is not possible to carry out post-dyeing and it is possible to freely control the combination of colors and the color tone. It has the drawback that it cannot

[Problems to be Solved by the Invention]

The object of the present invention is to use an aromatic polyvalent carboxylic acid containing a hydrophilic group and an aromatic polyvalent carboxylic acid without using a strongly polar carrier or a solvent such as dimethyl sulfoxide which leaves a problem in the environment as described above. And an aromatic polyamide fiber produced from an aromatic diisocyanate are coexisted with a reducing agent and an alkaline liquid, and dyed to a practical density using a vat dye having good fastness to sunlight, and an aromatic polyamide fiber having good dyeing light fastness Is to provide.

[Means for solving the problem]

As a result of intensive studies to solve the above problems, the present inventors have made aromatic aramid fibers containing a hydrophilic group coexist with a reducing agent and an alkaline liquid, and use a vat dye having a sunlight fastness of 7 or higher. The present invention has been completed by finding that a dyed product of high practical concentration can be obtained by dyeing and that the light resistance thereof is also good.

That is, the present invention is an aromatic polyamide fiber produced from an aromatic polyvalent carboxylic acid containing a hydrophilic group, an aromatic polyvalent carboxylic acid and an aromatic diisocyanate, in the presence of a reducing agent, an alkaline solution, light fastness A method for dyeing aromatic polyamide fibers, which comprises dyeing with a vat dye of 7th grade or higher.

[Preferred embodiment for carrying out the invention]

The hydrophilic group of the aromatic polycarboxylic acid containing a hydrophilic group used in the present invention, -SO ₃ M _1: acid base represented by (M ₁ alkali metal), -COOM ₂ (M ₂ A group of a carboxylate represented by (alkali metal),
Specific examples of the aromatic polycarboxylic acid containing SO ₃ M ₁ include sodium isophthalic acid-5-sulfonate, sodium terephthalic acid-2-sulfonate 4,4′-diphenyl ether-dicarboxylic acid-2,2′- Disodium sulfonate, 4,4'-diphenyl-dicarboxylic acid-2,2'-disodium sulfonate, 4,4'-diphenylsulfide-dicarboxylic acid-2,2'-disodium sulfonate, etc., and sodium-2,4 -Diaminobenzene sulfonate, 4,4'-diaminodiphenylmethane-2,2'-di-sodium sulfonate and the like are also mentioned, and potassium and lithium salts of the above compounds are also effective.

Specific examples of the aromatic polycarboxylic acid containing -COOM ₂ include trimellitic acid monosodium salt, pyromellitic acid disodium salt, butanetetracarboxylic acid disodium salt, and potassium and lithium salts of the above compounds. Is also effective.

The method for incorporating these hydrophilic groups into the aromatic polyamide fiber is not particularly limited, for example, by mixing an aromatic polyvalent carboxylic acid and a polyvalent carboxylic acid having a hydrophilic group, and performing high temperature solution polymerization from an aromatic diisocyanate. , A method of incorporating it as a copolymer. Further, there is a method in which these copolymers are mixed and dissolved in a polymer prepared from an aromatic polyvalent carboxylic acid having no hydrophilic group and an aromatic diisocyanate, and the resulting mixture is contained.

The effect of the hydrophilic group is about 5 to 10% better than the one containing the hydrophilic group as a copolymer, which is mixed and dissolved, but in any case, practical dyeing As a result of examining both the concentration and the practical strength of the fiber, the concentration of the hydrophilic group in the aromatic polyamide fiber is
The range of 0.5 mol% to 50 mol%, preferably 2 mol% to 30 mol% is preferable.

As the dye used in the method of the present invention, a vat dye having good light fastness is selected.

As a composition of a dyeing bath for dyeing an aromatic polyamide fiber containing a hydrophilic group with such a dye, in addition to vat dyes, as dyeing aids, glucose, fructose, mannose and other aldohexoses, maltose , Oligosaccharides such as sucrose, and polysaccharides such as starch and cellulose. Although the action of these dyeing aids is not clear,
It has the effect of preventing over-reduction of vat dyes during high-temperature dyeing (80 ° C or higher) and suppressing changes in color tone.

For the reduction of vat dye, hydrosulfite, zinc salt of hydroxymethanesulfinic acid known under the trade name of dechlorin, or sodium hydroxymethanesulfinate known under the trade name of Rongalit C is used.

As the alkaline liquid, sodium hydroxide, potassium hydroxide, water glass, potassium carbonate or a mixture thereof is used.

The concentrations of these dyeing assistants, reducing agents, and alkaline solutions are not particularly limited, and are sufficient if they are within the concentration range commonly used for ordinary dyeing. Generally, the dyeing aid is 1 to 20 g /,
The reducing agent is 5-40g /, and the concentration of the alkaline solution is 0.1-5% by weight.
Use to some extent.

Further, addition of an electrolyte such as sodium chloride or sodium sulfate is also effective for improving the dyeing property.

The temperature for dyeing in the above bath composition is 60 to 150.
The temperature and the dyeing time are preferably 30 to 90 minutes.

The aromatic polyamide fiber containing a hydrophilic group after dyeing is oxidized and soaped with a vat dye according to a usual post-treatment, and the temperature at this time is preferably 80 ° C. or higher.

〔Example〕

The present invention will be described below with reference to examples. In addition, a part shows a weight part in an example.

Example 1 16.61 g (0.10 mol) of terephthalic acid, 28.42 (1.70 mol) of isophthalic acid, and isophthalic acid-5-sulfone were placed in a 5 separable flask equipped with a stirrer, a thermometer, a condenser, a dropping funnel, and a nitrogen introducing tube. 53.62 g (0.2 mol) of sodium acidate (hereinafter abbreviated as S-IPA), 0.58 g (0.01 mol) of potassium fluoride and 3.51 of a solvent 1,3-dimethyl-2-imidazolidinone (hereinafter abbreviated as DMI) are added,
The mixture was heated to 200 ° C., and 350.1 g (2.01 mol) of tolylene-2,6-diisocyanate was added dropwise over 2 hours. The polymer became increasingly viscous. After further stirring, it was cooled to room temperature. The pale yellow viscous liquid was degassed under reduced pressure, filtered, heated to 100 ° C., and extruded into a heated air stream from a spinning machine having a 100-hole spinneret to give a dry-spun tow. This tow was stretched 4 times in hot water at 80 ° C. containing 15% DMI and 30% calcium chloride, and then DMI and calcium chloride were removed in hot water. Further, heat setting was performed at 270 ° C. for 5 minutes to obtain a filament of 10 d / 100 fil.

This filament was wound around a 4 cm × 5 cm SUS wax, put in a dyeing bath having the following composition, and treated at 130 ° C. for 90 minutes. Then it was cooled to room temperature.

Mikethren RSN s / f (manufactured by Mitsui Toatsu Dyestuffs Co., Ltd.) 0.2 parts 30Be′NaOH 3.2 parts Glucose 0.2 parts Rongalit-C 1.2 parts Water 195 parts Subsequently, 1.2 parts of sodium perborate is added and treated at 90 ° C. for 30 minutes. Oxidize. Subsequently, the product was treated for 10 minutes in a soap pink liquid containing 95% of monogen paste (anionic surfactant manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) at 95 ° C, then washed with water and dried.

The filament was dyed dark blue. This dyed filament is measured with a UV long life fade meter FAL5H (manufactured by Suga Test Instruments) (hereinafter abbreviated as FOM).
Irradiated for an hour. The dyeing fastness after irradiation was grade 4 on the blue scale.

Example 2 Polymerization and dyeing were performed in the same manner as in Example 1 except that the proportion of sodium isophthalic acid-5-sulfonate was changed as shown in the following table, and the dyeability and the dye fastness were evaluated.

Comparative Example 1 The filaments having different S-IPA contents prepared in Example 1 and Example 2 were respectively Mit instead of Mikethren RSN s / f.
Dyeing and dyeing fastness were evaluated in the same manner as in Example 2 except that sui Tsuya Indigo2B Super Fine (Vat dye manufactured by Mitsui Toatsu Dye Co., Ltd.) was used. Table of results
It is shown in FIG.

From this, it is understood that the indigo-based vat dye has good dyeability but low dyeing fastness. However, it is understood that the dye containing S-IPA has improved dyeability and dye fastness as compared with the dye containing no S-IPA.

Example 3 The filaments having different S-IPA contents produced in Examples 1 and 2 were replaced with Mikethren RSN s / f (Vat dye manufactured by Mitsui Toatsu Dyestuffs Co., Ltd.), and Mikethren Dark Blue BO was used.
Dyeing was conducted in the same manner as in Example 1 except that As / f (Vat dye manufactured by Mitsui Toatsu Dye Co., Ltd.) was used and glucose was not used,
The dyeability and dye fastness were evaluated. The results are shown in Table-3.

Comparative Example 2 Dehydrated N, N'-dimethylacetamide (DMAC) 5
646.2 g of metaphenylenediamine distilled in was dissolved in the solution and cooled in a dry ice-methanol bath at -15 ° C. to this
1215 g of isophthaloyl chloride was added dropwise with stirring to maintain 20 ° C. After the dropping yield, the temperature was raised to 30 ° C in 30 minutes and kept at 30 ° C for 120 minutes.

After the reaction was completed, add 450 g of anhydrous calcium hydroxide and add 100 ° C.
The mixture was heated at 90 ° C. for 90 minutes to neutralize the produced hydrogen chloride. This is designated as a polymerization liquid (a).

Similarly, 316.3 g of sodium isophthaloyl chloride-4-sulfonate (abbreviated as S-IPC) and 210.6 g of isophthaloyl chloride were added to metaphenylenediamine 226.
4 g were polymerized in 170 g DMAC. To this, 288 g of anhydrous calcium chloride was added to neutralize the produced hydrogen chloride. This polymerization liquid is referred to as (b).

The polymerization liquid (a) and the polymerization liquid (b) were mixed at the following ratios to form a uniform solution. (See Table-4) Spinning was performed from these solutions in the same manner as in Example 1,
I got each filament. Each of these filaments was dyed in the same manner as in Example 1 and evaluated for dyeability and dye fastness. The results are shown in Table-5.

In addition, the filament C-2-2 to C-2-4 is set to 250
When it was placed in an oven at ℃ for 10 minutes and left for a while, it tasted brown.

[Effect] By applying the method of the present invention to an aromatic polyamide fiber containing a hydrophilic group, it can be easily dyed in a practical concentration with a wide range of light fastness good vat dyes, the dyed product is for clothing, It can be used as an interior.

 ─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP-A-2-53974 (JP, A) JP-A-3-76879 (JP, A) JP-A-2-221471 (JP, A) JP-A-63- 182482 (JP, A) JP-A-63-189586 (JP, A)

Claims (3)

(57) [Claims] 1. A lightfastness of an aromatic polyamide fiber produced from an aromatic polyvalent carboxylic acid containing a hydrophilic group, an aromatic polyvalent carboxylic acid and an aromatic diisocyanate in the presence of a reducing agent and an alkaline solution. A method for dyeing aromatic polyamide fibers, which comprises dyeing with a vat dye of grade 7 or higher. 2. The method according to claim 1, wherein the hydrophilic group is a sulfonate group represented by —SO ₃ M ₁ (M ₁ represents an alkali metal). 3. The method according to claim 1, wherein the hydrophilic group is a carboxylate group represented by —COOM ₂ (M ₂ represents an alkali metal).