JPH0340881A - Dyeing of polyester-based fiber and vegetable dye dyeable polyester - Google Patents

Abstract

PURPOSE:To obtain a dyed material having excellent dyeability, improved washing resistance and light resistance and high utility by treating 5-sulfoisophthalate copolymer polyester-based yarn with an aqueous solution of metallic salt such as salt and dyeing the yarn with vegetable dye. CONSTITUTION:Polyester-based yarn copolymerized with 5-sulfoisophthalate, preferably alkali metal salt is treated with an aqueous solution of sulfate of one metal selected from the group consisting of iron, copper and aluminum and dyed with vegetable dye (e.g. safflower, madder or Lithospermum officinale var. erythrorhizon).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for dyeing polyester fibers and polyester dyeable with vegetable dyes. The present invention relates to a method for dyeing polyester fibers with a vegetable dye, and a polyester copolymerized with a 5-sulfoisophthalic acid metal salt and dyeable with a vegetable dye.

[Conventional technology]

Polyester fibers are difficult to dye due to the following reasons: ■ They do not have functional groups that bind to dyes, ■ Their fiber structure is dense, and ■ They are hydrophobic. , carrier dyeing and high-pressure dyeing are common.

However, the hue of the dyed product obtained is pastel-like and lacks clarity compared to that of natural fibers. As a method to overcome the above-mentioned drawbacks, so-called "° cationic dyeable polyester fibers", in which 5-sulfoisophthalate is copolymerized to introduce dye-bonding functional groups, have been developed and are commonly used.

On the other hand, the diversification and individualization of clothing materials in recent years has been remarkable. The dyed fabric industry is no exception. In other words, in recent years, clothing materials are being sought after not only for their economic and practical value, but also for their spiritual and cultural value. In this context, dyed woven and knitted fabrics are required not only to have clear or indistinct hues, but also to have unique, complex colors that appeal to the senses. Examples of dyed products with the above-mentioned characteristics include so-called "plant dyeing" using traditional Japanese vegetable dyes.
Fabrics dyed using this method can be mentioned. However, dyeing with the above-mentioned vegetable dyes is limited to natural fibers such as silk and wool, and is completely impossible to dye synthetic fibers, especially fibers with low dyeability such as polyester fibers.

The present inventors have made various attempts to achieve the above object. For example, there have been attempts to impart dyeability to polyester fibers by introducing the third precept such as polyethylene glycol component, and further attempts have been made using the above-mentioned "cationic dyeing technology."

In the former case, the mobility of the rigid polyester molecular chains was improved, resulting in easy dyeability and dyeability with vegetable dyes, but the degree of dyeing (color development) was low and the color fastness was insufficient. .

Although the latter improves the degree of dyeing compared to the former, the dye fastness is extremely poor, and we learned that there is a limit to simply extending cationic dyeing technology, and that a more drastic solution is required.

[Problem to be solved by the invention]

The present invention provides a method for dyeing polyester fibers that can be dyed in a variety of unique, deep colors that were impossible to obtain with conventional polyester fibers, and a polyester dyeable with vegetable dyes. Specifically, it is possible to obtain extremely diverse and calm colors even with polyester fibers, such as vegetable dyeing.
The dyed fabric has excellent color fastness, ■ The mechanical performance of the fibers that make up the dyed fabric is excellent, ■ The dyeing operation is easy, and ■ The multifilament that makes up the woven and knitted fabric can be easily produced. The purpose of the present invention is to provide a polyester dyeing method that solves all problems in terms of color, practicality, and production, and to provide a polyester dyeable with vegetable dyes.

[Means to solve the problem]

In the present invention, 5-sulfoisophthalate copolymerized polyester fibers are treated with an aqueous solution of a salt of at least one metal selected from the group consisting of iron, copper, and aluminum.
This is a method for dyeing polyester fibers, which is characterized by dyeing them with a vegetable dye afterwards.

The dyeing mechanism of the dyeing described above is still being elucidated and is not necessarily clear, but when at least one metal selected from the group consisting of iron, copper, and aluminum is used, this metal can interact with the fiber and dye. As a result, even vegetable dyes can develop sufficient color at room temperature.
Furthermore, it is estimated that the color fastness is dramatically improved.

The at least one metal salt selected from the group consisting of iron, copper, and aluminum in the present invention is not particularly limited as long as it is water-soluble, but examples of anions include halide ions, acetate ions, sulfate ions, , phosphate ion, oxalate ion, borate ion, and especially sulfate ion, chloride ion CC1-', (1,-
”), more favorable results can be obtained.

More preferable results can be obtained when the temperature of the aqueous solution of the metal salt is high.

In addition, the pH of the aqueous solution depends on the dye and metal salt used.
For example, if the dye is safflower and the metal salt is carbon
In staining with uSOa, more favorable results are obtained under acidic conditions (pH 2 to 5).

At this time, the dense structure of the polyester fiber is swollen,
A swelling agent may be added to further enhance color development. Swelling agents used include acetone, methanol, phenol, tetrahydrofuran, dioxane, diethylene glycol dimethyl ether, benzyl benzoate and mixtures thereof.

The vegetable dyes that can be used in the present invention are not necessarily limited, but include vegetable dyes used for so-called "plant dyeing", such as safflower, madder, purple root, indigo,
Yellowfin tuna, turmeric, cariyasu, gardenia, Asen, sawtooth oak,
Dyes such as T-zi, wheel plum, plum, gobaishi, and rockwood can be used. In addition, more general flowers,
Wild plants, vegetables and fruits, such as mandarin orange and onion juice, can be used, so the scope of its use is extremely wide.

In addition, regarding the dyeing method, each treatment can be performed once to obtain a sufficient dyed product, and if deeper color dyeing is required, the treatment may be performed multiple times. Furthermore, since dyeing can be carried out satisfactorily even under normal pressure, a complicated and large-sized dyeing device is not necessarily required, and the dyeing can be carried out extremely easily.

The polyester fibers used in the present invention are fibers mainly made of polyester consisting of terephthalic acid and alkylene glycol having 2 to 6 carbon atoms, and dicarboxylic acids other than terephthalic acid or carbon atoms containing dicarboxylic acids other than terephthalic acid or The fibers may be obtained by copolymerizing less than 20 mol% of 2 to 6 diols other than alkylene glycol. Particularly preferred is one made of polyethylene terephthalate.

Furthermore, the 5-sulfoisophthalate of the present invention includes 5-sulfoisophthalate.
-Sulfoisophthalic acid alkali metal salts and 5-sulfoisophthalic acid quaternary phosphonium salts. The types of alkali metal ions and phosphonium ions are not particularly limited, but examples of alkali metals include sodium, potassium, lithium, etc., and examples of phosphonium include tetraalkylphosphonium, tetraarylphosphonium, especially tetramethylphosphonium, tetraethylphosphonium, and tetramethylphosphonium. Butylphosphonium, tetraphenylphosphonium, etc. are preferable, and especially in the case of tetrabutylphosphonium, even if the copolymerization ratio is increased, troubles due to viscosity effects in the polymerization and silk-spinning process are eliminated, and the polymerization (high [η]) is achieved. This is more preferable since it is possible to achieve both color development and fiber strength.

There is no need to pay special attention to the physical properties of the fibers used in the dyeing of the present invention, and it is sufficient to have the same properties as ordinary polyester fibers.For example, looking at the elongation, the elongation is 15.
- Normally drawn yarn of about 40%, and even elongation of 40 to 80%
A high-speed spun product of 2.0 g/denier can also be used, and the strength level is preferably 2.5 g/denier or higher, more preferably 3.0 g/denier.

In addition, the shrinkage rate is preferably 20% or less, and 5 to 1
More preferably, it is 5%.

Furthermore, if bulkiness is required, bulkiness can be imparted by false twisting, and the fibers can be spun after being made into staple fibers and used as spun yarn.

Next, regarding the structure and form of woven and knitted fabrics, there is no need to make any special efforts; for example, woven structures include plain weave, satin weave, and twill weave; knitted fabrics have various complex structures ranging from the basic structures of weft knitting and warp knitting. &11 weaves can be used. Various interwoven and interwoven fabrics can also be used as the woven or knitted fabric of the present invention.

The present invention also provides a copolymerized polyester in which the main constituent component is alkylene terephthalate and a metal salt of 5-sulfoisophthalate is copolymerized, wherein the metal of the metal salt is selected from the group consisting of iron, copper, and aluminum. and the content of the metal salt is 0.
．． It is a vegetable dye dyeable polyester characterized by having a content of 1 to 20 mol%.

In the present invention, a polyester whose main component is an alkylene terephthalate is a polyester whose main constituent is an alkylene glycol having 2 to 6 carbon atoms, and a dicarboxylic acid other than terephthalic acid or Diols other than alkylene glycol having 2 to 6 carbon atoms may be copolymerized in an amount of less than 20 mol %. Usually, it is a polyester having an intrinsic viscosity of 0.3 or more, preferably 0.35 to 1.2, as measured in 0-chlorophenol at 25°C. This polyester can be obtained by the well-known melt polymerization method.

The metal of the 5-sulfoisophthalic acid metal salt to be copolymerized is:
At least one member selected from the group consisting of iron, copper, and aluminum. Iron may be divalent or trivalent, and copper may be monovalent or divalent. Aluminum is trivalent.

The proportion of 5-sulfoisophthalic acid metal salt to be copolymerized is:
It is preferably 0.1 to 20 mol%, more preferably 0.4 to 10 mol%, based on alkylene terephthalate, which is the main structural Ca component. If it is less than 0.1 mol%, the improvement in light resistance and washing durability will be insufficient, while if it exceeds 20 mol%, the original physical properties of alkylene terephthalate, which is the main component, will be significantly lost, which is undesirable. .

The proportion of the sulfonic acid moiety of the 5-sulfoisophthalic acid component of at least one metal salt selected from the group consisting of iron, copper and aluminum is equal to or less than the proportion of the entire 5-sulfoisophthalic acid component to be copolymerized. good.

The counter ion other than at least one metal selected from the group consisting of iron, copper and aluminum in the sulfonic acid moiety of the 5-sulfoisophthalic acid component is usually an alkali metal ion or a quaternary phosphonium salt.

The 5-sulfoisophthalic acid metal salt formed contains anions other than sulfonic acid anions, such as halide ions such as fluoride ions, chloride ions, bromide ions, iodide ions, and acetate ions. Good too. Furthermore, one or more sulfonic acid anions derived from 5-sulfoisophthalic acid, one or more of the metals, and one or more anions other than the sulfonic acid anions derived from 5-sulfoisophthalic acid form a complex. It may be formed.

The 5-sulfoisophthalic acid metal salt of the present invention contains 0.1 to 20 mol% of an alkali metal 5-sulfoisophthalic acid salt and/or a quaternary phosphonium salt of 5-sulfoisophthalic acid.
It is formed by contacting a copolymerized polyester containing copolymerized alkylene terephthalate as a main component with an aqueous solution of at least one metal salt selected from the group consisting of iron, copper, and aluminum. The types of alkali metal salts and quaternary phosphonium salts are not particularly limited, and the aforementioned ones are preferably used.

The at least one metal salt selected from the group consisting of iron, copper, and aluminum in the present invention is not particularly limited as long as it is water-soluble, and the above-mentioned anions are preferably used.

By impregnating these metal salts into the polyester and exchanging the metal ions with sodium ions and/or quaternary phosphonium ions, iron, copper, and aluminum can be removed from iron, copper, and aluminum in a polyester whose main component is alkylene terephthalate. It is possible to obtain a copolymerized polyester in which at least one metal sulfonate selected from the group consisting of: If the metal salt is difficult to impregnate, heating is preferred.

Usually, impregnation with this metal salt is carried out by boiling an aqueous metal salt solution at normal pressure.

At this time, the swelling agent may be added so that the metal salt can more easily enter into the polymer.

When the thus obtained polyester is thoroughly washed with water, the vegetable dye-dyable polyester of the present invention can be obtained.

[Effect]

In order to activate polyester fibers that are originally inert to dyes, a functional group that binds to the dye is required, as in the cationic dyeing technology mentioned above, and this bond is extremely stable. As a specific measure, when dyeing polyester fibers, the fibers are treated in advance with an aqueous solution of at least one metal selected from the group consisting of iron, copper, and aluminum. However, if a dyeing process is applied afterwards, it is surprising that not only can even vegetable dyes produce sufficient color at room temperature, but the color fastness, which was a problem with conventional techniques, has dramatically improved. This will improve it to a practical level.

[Example] Hereinafter, the present invention will be described in more detail with reference to Examples.

The definition of the evaluation method used in the present invention is as follows.

(Color development) The fabric made of multifilaments used in the present invention is treated with an aqueous metal salt solution, and then dyed with a vegetable dye.
After washing with water and drying, it was used as a sample for color development evaluation. The degree of color development (dark, light) was qualitatively determined with the naked eye. In addition, the same method was used to evaluate the case where the metal salt aqueous solution treatment was not performed.

The evaluation criteria are as follows.

O: The degree of dyeing of the dyed tube knit is sufficient.

Δ: The degree of staining is insufficient and the stain is slightly faint.

×: Not dyed at all).

(Dyeing fastness) (a) Washing fastness The dyed woven or knitted fabric is tested under JIS L-0844-73A-
The degree of discoloration of the dyed fabric was visually determined according to Method 2.

Judgment was made by grade, with grades 1 to 5, and grades 3.5 and above were considered passed.

(b) Light fastness dyed woven and knitted fabrics with xenon arc JISL-084
3-71 3rd light method 2*t; z, determined by naked eye.

Judgments were made using the same grading as washing fastness.

(Strength and elongation) The stress-elongation curve of the multifilament that makes up the woven or knitted fabric is determined at room temperature using a vertical tensile test, and the strength at the point where the stress is maximum is divided by the fineness (denier) of the multifilament. The value was taken as the strength, and the elongation up to the point where the stress was maximum was taken as the elongation.

(Overall Judgment) ○: Color development, color fastness, and fiber physical properties after dyeing are all good and can be used practically.

Δ: There is room for further improvement in terms of color development and color fastness.

×: No color development at all, and dyeing with vegetable dyes is difficult.

Reference example 1 5-sulfoisophthalate tetrabutylphosphonium
2 g each of mole% copolymerized polyethylene terephthalate fibers (single fineness 1.1 denier, intrinsic viscosity 0.60
) was immersed in an aqueous solution containing 2% by weight of the following metal salt and 1% by weight acetic acid, and treated at 100''C for 1 hour. After thoroughly washing the fiber with water and drying, the amount of elements in the fiber was measured.

The results are shown in Table 1.

Examples 1 to 3, Comparative Examples 1 to 9 5-sulfoisophthalate tetrabutylphosphonium
Polyethylene terephthalate fiber copolymerized with mol% (single filament fineness 1.1 denier, intrinsic viscosity 0.60), polyethylene terephthalate fiber copolymerized with 5 mol% sodium 5-sulfoisophthalate (single filament fineness 1.1 denier, intrinsic viscosity 0.60) viscosity 0.42) and polyethylene glycol (
Polyethylene terephthalate fiber (number average molecular weight 2,000) copolymerized with 10% by weight of dimethyl terephthalate (single fineness 1.1 denier, intrinsic viscosity 0.64
) were each made into a fabric and treated with a metal salt in the same manner as in Reference Example 1. This was immersed in an aqueous solution containing 2% by weight of safflower dye, 1.5% by weight of acetic acid, and 1% by weight of tannic acid at a bath ratio of 70 times and brought to 100'C under normal pressure for 20 minutes. After washing and drying, the L value was measured using a digital colorimetric color difference calculator (manufactured by Suga Test Instruments ■). Wash this 5 times in total under the following conditions,
Wash and dry the fabric each time you wash it, and then wash it in the same way as above.
The value was measured. The results are shown in Table 2.

The washing was carried out by placing 22 g of 70°C water, 22 g of detergent Zabu (manufactured by Kao Corporation) and 20 g of fabric in a beaker and stirring for 20 minutes.

Table 2 Table 2 (Continued) As shown above, the dye does not come off when 5-sulfoisophthalic acid is copolymerized even after washing, but the dye does not come off when polyethylene glycol is copolymerized.

The strength and elongation of the fibers used in this fabric before and after dyeing are shown in Table 3. However, the strength and elongation after dyeing is that before washing.

Table 3 Table 3 (continued) Examples 4 to 10, Comparative Examples 10 to 23 The polyethylene terephthalate fibers shown in Table 4 were made into fabrics, and an aqueous solution containing 2% by weight of the metal salts shown in Table 5 and 1% by weight of acetic acid was prepared. and treated at 100°C for 1 hour.

After washing this fiber thoroughly with water, 2% by weight of the lac dye,
It was immersed in an aqueous solution containing 1.5% by weight of acetic acid and 1% by weight of tannic acid at a bath ratio of 70 times, and brought to IoooC at normal pressure for 20 minutes. After washing and drying, the sample was placed in a xenon tester (model XW-20) manufactured by Shimadzu Corporation along with a blue scale based on JIS LO841, and exposed to light at a current of 2OA for 20 hours to examine light resistance. The light fastness was evaluated by comparing the degree of discoloration of the dyed fabric with the degree of discoloration on a blue scale, and the results are shown in Table 5, where grade 1 is the worst and grade 8 is the best.

Table 5 Table 5 (continued) Examples 11 to 16, Comparative Examples 24 to 39 Transesterification and i1i! using dimethyl terephthalate and ethylene glycol according to a conventional method. Polymerization was performed to obtain a polyethylene terephthalate polymer. At this time, 5-sulfoisophthalate or polyethylene glycol (number average molecular weight = 2
A polymer was also produced by copolymerizing 0,000). The resulting polymer chips were dried at 140'C for 5 hours, then melt extruded at 285'C, and after cooling and solidification,
An oil agent was applied and it was wound up at 400 m/min. Subsequently, stretching heat treatment (stretching after preheating with a preheating roller at 80'C,
After heating with a plate heater at 0° C., the mixture was wound up through a cooling roller to obtain a 75-denier, 24-filament multifilament.

The resulting multifilament polymers are shown in Table 6.

Table 6 The above drawn yarn was knitted and soaked in a 50"C surfactant [Monogen (manufactured by P&G)] aqueous solution. After removing the spinning oil, it was washed with water and dried. Then, it was set at 180°C for 1 minute. This was used as a sample for dyeing.The dyeing operation of the tube knit was carried out in two cases: after treatment with an aqueous metal salt solution, washing and drying, and then dyeing, and when dyeing without treatment with a metal salt.The treatment with an aqueous metal salt solution was An aqueous solution containing 2% by weight of cupric sulfate and 1% by weight of acetic acid was used at a bath ratio of 100 times and boiled for 1 hour.

For dyeing, safflower dye was used at 2% owf, immersed in a bath ratio of 100 times, and boiled for 30 minutes.

After the dyed tubular knits were washed with water and dried, color development, color fastness, and strength and elongation were evaluated.

The results are shown in Table 7.

(The following is a blank space.) Notes indicate that the fastness was not determined because it was not dyed.

Table 7 (continued) As is clear from Table 7, Comparative Example 2 without functional groups
In the fibers of Nos. 4 and 25, no coloring due to vegetable dyes was observed, and in the fibers of Comparative Examples 34 to 36, in which polyethylene glycol was copolymerized, as the copolymerization ratio was increased, the coloring property improved. However, the color fastness is still insufficient, and even when treated with an aqueous solution of a metal salt, the color fastness is still insufficient.

On the other hand, the knitted fabrics copolymerized with 5-sulfoisophthalate and treated with an aqueous metal salt solution, for example, the knitted fabrics of Examples 11 to 13, had extremely good color development, color fastness, and fiber physical properties after dyeing. be.

In particular, in the case of the fibers of Examples 14 to 18 in which the copolymerization component was tetrabutylphosphonium 5-sulfoisophthalate, even if the copolymerization ratio was increased, the decrease in fiber physical properties was small, which was extremely preferable. .

Example 19, Comparative Example 38 Using the polymer 8, a spinning and drawing operation was performed in the same manner as in Example 11 using a spinneret having a trilobal type discharge hole, and a 75 denier filament consisting of a filament having a triangular cross-sectional shape was obtained. , a multifilament of 36 filaments was obtained. A woven fabric with a basis weight of 100 g/c+fl consisting of a satin weave using this multifilament as the warp and weft was produced by a known method and used as a sample for dyeing. The metal salt aqueous solution treatment and dyeing treatment were carried out in the same manner as in Example 11.

Example 1 shows color development, color fastness, and fiber properties after dyeing.
Evaluation was made in the same manner as in 1. The results are shown in Table 8.

The woven fabric of Example 19 had a good texture with a silky touch, and both color development and fiber physical properties after dyeing were good.

On the other hand, the fabric of Comparative Example 38 had room for improvement in terms of color fastness.

Table 8 (Continued) [Effects of the Invention] By using the dyeing method of the present invention or using the vegetable dye dyeable polyester of the present invention, the dye does not come off even when washed, and the dye has good light resistance. For example, it is possible to provide polyester fibers with colors that appeal to the senses, such as "plant-dyed" colors.

That is, according to the present invention, it is possible to obtain polyester fibers dyed with vegetable dyes that have colors that were thought to be impossible to express with synthetic fibers, such as retro or traditional styles, and improve the color fastness of dyed products. It has extremely good properties and can be put to practical use.Furthermore, the mechanical properties of the woven or knitted fabric after dyeing are also excellent and can withstand practical use.
It becomes possible to provide dyed polyester fibers having excellent properties such as ease of manufacture and production.

In addition, the vegetable dye-dyable polyester of the present invention exhibits a very large thickening effect when the polymer is melted when a divalent or higher metal ion is used as a counter ion to the sulfonic acid of the 5-sulfoisophthalic acid component. Therefore, by changing the amount of copolymerization, the viscosity of the polymer during melt blow molding can be increased to make molding easier.

In addition, in order to produce polyalkylene terephthalate by copolymerizing a divalent or higher metal ion as a counter ion to the sulfonic acid of the 5-sulfoisophthalic acid component, the 5-sulfoisophthalic acid metal salt is added during polymerization. Then, a three-dimensional mesh structure of polymer chains is generated due to ionic crosslinking.

Therefore, the viscosity of the molten polymer increases significantly;
Although it was not possible to stir to increase the degree of polymerization or to discharge the produced polymer from a polymer manufacturing device, the method of the present invention yields a polymer with a high degree of polymerization, so it can be used as fibers, films, and resins. It becomes possible.

Claims (2)

[Claims] (1) 5-sulfoisophthalate copolymerized polyester fibers are treated with an aqueous solution of at least one metal salt selected from the group consisting of iron, copper, and aluminum, and then dyed with a vegetable dye. A method for dyeing polyester fibers. (2) A copolymerized polyester whose main constituent component is alkylene terephthalate and which is copolymerized with a metal salt of 5-sulfoisophthalate, in which the metal of the metal salt is iron,
At least one selected from the group consisting of copper and aluminum, and the content of the metal salt is 0.1 to 20
Vegetable dye-dyeable polyester characterized in that mol%.