TWI910991B - Method for manufacturing dye composition and dye composition - Google Patents

Abstract

The present invention provides a method for manufacturing dye composition and the manufactured dye composition thereof. The method includes adding a large amount of cold water to a blue dye raw material for desalination and purification, so that the salt content in the blue raw material liquid that has been processed by the desalination and purification process is less than 35% of the salt content in the blue raw material liquid that has not been processed by the desalination and purification process, and then adding an auxiliary agent and co-solvent to obtain the dye composition. The auxiliary agent increases the solubility of the blue dye, and the co-solvent maintains the solubility of the dye above a certain level. The dye composition manufactured by this method has high solubility, and has desirable color fastness and uptake while maintaining a certain solubility.

Description

Methods for manufacturing dye compositions and dye compositions

This invention relates to the technical field of manufacturing dye compositions, and particularly to a method for manufacturing dye compositions and dye compositions.

Dyeing is an important process for adding color to textiles and other materials, and it holds a significant economic position in the dyeing and finishing industry, the textile industry, and other related industries. Among them, acid dyes are one of the important dyes used in this process.

Acid dyes are a class of water-soluble dyes with acidic groups in their structure. They can bind to the amino groups in protein fiber or polyamide fiber molecules via ionic bonds and are suitable for acidic, weakly acidic, or neutral conditions. Acid dyes are mainly used for dyeing and printing on protein fibers such as wool and silk, as well as polyamide fibers. They can also be used for coloring leather, inks, paper, and cosmetics, as well as for food coloring.

The solubility of acid dyes in water is an important factor in their effectiveness. The solubility determines how easily acid dyes dissolve and are applied to materials. If the solubility is extremely low, they cannot color hydrophilic fibers, resulting in dye spots during dyeing and uneven fabric color.

Therefore, acid dyes with excellent colorfastness ensure that dyed materials retain their color after exposure to environmental factors such as light, water, and heat. Thus, high solubility in water and excellent colorfastness are important indicators for acid dyes.

One key factor affecting the solubility of acid dyes is the salt concentration in the semi-finished dye product. The higher the degree of purification of the semi-finished dye product, the higher its solubility. More specifically, the higher the salt concentration in the semi-finished dye product (unpurified or poorly purified), the lower the dye's solubility. Acid dyes (such as blue dye) produced by current processes have poor solubility, approximately only 2 grams per liter (g/L), due to their high salt content. At around 20°C, the solubility further decreases to only about 1 g/L.

Therefore, in existing technologies, to improve dye solubility, a dispersant is added to the semi-finished dye, and it is then ground and dispersed in a mill for a long time until the dye molecules become smaller (e.g., ground and dispersed to an average particle size of about 800 nm), thereby improving the dye solubility. However, the grinding structure of the mill is metallic, and the long-term grinding process will cause the precipitation of metal ions in the grinding structure, resulting in the presence of heavy metal residues such as chromium (Cr), cobalt (Co), and iron (Fe) in the ground dye. These heavy metals are dangerous from a toxicological and environmental perspective, and will have adverse health effects on the subsequent application of the dye in textiles and subsequent contact with the human body. Therefore, this method should be eliminated. In addition, adding a step to remove residual heavy metals would require additional costs and procedures, and the washing of heavy metals and the discharge of wastewater would also cause environmental problems such as the treatment of dye wastewater.

Therefore, the purpose of this invention is to provide a dye composition to solve the problem in the prior art that, in order to improve the solubility of acid dyes, a grinder is used to grind the dye molecules to a smaller particle size, resulting in heavy metal residues in the ground dye.

This invention provides a method for manufacturing a dye composition, comprising the following steps: providing a blue dye raw material; adding water to the blue dye raw material to form a blue raw material solution, and subjecting the blue raw material solution to a desalination and purification process, wherein the desalination and purification process includes mixing the blue raw material solution and water in a ratio between 1:5 and 1:100 to carry out desalination and purification, so that the salt content in the blue raw material solution treated by the desalination and purification process is reduced to less than 35% of the salt content in the blue raw material solution that has not undergone the desalination and purification process; drying the purified blue raw material solution to form a blue dye; and mixing the blue dye with a cosolvent and a cosolvent to obtain the dye composition.

In one embodiment of the present invention, the blue dye comprises the structure of the following chemical formula (1), and the cosolvent comprises polyvinylpyrrolidone; Chemical formula (1).

In one embodiment of the invention, the dye composition further includes a cosolvent, which is one of the groups consisting of soluble starch and glucose.

In one embodiment of the present invention, the amount of the cosolvent is 5 to 65 parts by weight relative to 100 parts by weight of the blue dye, and the amount of the cosolvent is 35 to 95 parts by weight.

In one embodiment of the invention, the dye composition further includes an acid dye.

In one embodiment of the present invention, the weight ratio of the blue dye to the solubilizer is in the range of 1:0.02 to 0.4.

In one embodiment of the present invention, the weight ratio of the blue dye to the acid dye is in the range of 1:0.04 to 0.2.

In one embodiment of the present invention, the weight ratio of the blue dye to the cosolvent can be in the range of 1:0.1 to 0.7.

In one embodiment of the present invention, in step S20, the desalination and purification process is carried out by adding a large amount of cold water to the blue raw material solution, wherein the ratio of the blue raw material solution to the cold water is in the range of 1:10 to 1:30.

On the other hand, the present invention also provides a dye composition prepared according to the method for manufacturing dye compositions as described above. The dye composition includes a blue dye, a solubilizer, and a cosolvent, and optionally also includes an acid dye.

The present invention provides a method for manufacturing dye compositions and dye compositions that purify dye raw material solutions with a large amount of cold water to remove a large amount of salts contained in the dye raw material solutions. This desalination and purification process significantly reduces the salt content in the blue raw material solution compared to the solution without the desalination and purification process. A solubilizing agent is added to improve the dye's solubility, and a co-solvent can be selectively added to maintain the dye's solubility at a certain level. In other words, desalting the dye raw material solution yields a highly purified dye raw material solution, which improves the dye's solubility. The solubilizing agent and co-solvent respectively enhance and maintain the dye's solubility, further increasing the dye's color intensity. This reduces the amount of dye used, making it environmentally friendly and lowering production costs. More importantly, the desalting purification process in the dye composition manufacturing method of this invention eliminates the need for long-term grinding of the dye, thus avoiding the problem of heavy metal residues in the ground dye caused by grinding the dye molecules to become smaller particles using a grinder.

The technical content and detailed description of this invention are now explained in conjunction with the drawings:

Please refer to Figure 1, which shows a schematic flowchart of a method for manufacturing a dye composition according to an embodiment of the present invention. As shown in Figure 1, the method for manufacturing the dye composition of the present invention includes the following steps:

Step S10: Provide a blue dye raw material;

Step S20: Add water to the blue dye raw material to form a blue raw material solution, and perform a desalination and purification process on the blue raw material solution; wherein, the desalination and purification process includes mixing the blue raw material solution and water in a ratio between 1:5 and 1:100 to carry out desalination and purification, so that the salt content in the blue raw material solution treated by the desalination and purification process is reduced to less than 35% of the salt content in the blue raw material solution that has not undergone the desalination and purification process;

Step S30: Dry the purified blue raw material solution to form a blue dye; and

Step S40: Mix the blue dye with a solvent and a co-solvent to obtain the dye composition.

In step S10, the blue dye raw material can be a currently known dye, for example, in this embodiment, a blue acid dye, but the present invention is not limited thereto.

Because commercially available dyes typically have high salt content, they easily cause scale or soap scum to form in the dyeing vat or pipelines after repeated use, requiring frequent cleaning of equipment or replacement of pipelines. Therefore, in step S20, adding a large amount of cold water to the blue raw material solution for desalination and purification can remove at least 65% of the salts. In different embodiments, adding a large amount of cold water to the blue raw material solution for desalination and purification can remove at least 80% of the salts. By adding a large amount of cold water to the blue raw material solution for desalination and purification, the salt content in the blue raw material solution treated with this desalination and purification process is reduced to less than 35% of the salt content in the blue raw material solution that has not undergone this desalination and purification process. In other words, the salt content in the blue raw material solution after large-volume cold water desalination and purification is significantly lower than that in the blue raw material solution that has not undergone this large-volume cold water desalination and purification process. The salt content of the former is reduced by at least 65%, that is, the salt content of the former is reduced to below 35 wt%; preferably, the salt content of the blue raw material solution after large-volume cold water desalination and purification treatment is reduced by at least 80% compared with the salt content of the blue raw material solution after not undergoing large-volume cold water desalination and purification treatment, that is, the salt content of the former is reduced to below 20 wt%.

Furthermore, after drying in step S30 to form the purified blue dye, in step S40, the desalted and purified blue dye is mixed with a solubilizer and a co-solvent to obtain the dye composition. The blue dye comprises the structure of the following chemical formula (1): Chemical formula (1).

In one embodiment, the dye of formula (1) used is a known compound that can be prepared by methods known in the literature, such as those described in U.S. Patent US2,008,796A. Specifically, for example, C.I. Acid Blue 129 can be reacted with formaldehyde to prepare the dye of formula (1); commercially available compounds can also be used.

The cosolvent used includes polyvinylpyrrolidone (PVP). By including this cosolvent, the dye composition of the present invention can significantly improve the solubility of the blue dye in water, thereby greatly increasing the solubility of the blue dye with the chemical formula (1) in water from less than 5 g/L to more than 20 g/L; more preferably, the solubility can be more than 30 g/L; even more preferably, an excellent solubility effect of 50~70 g/L can be achieved.

Preferably, the polyvinylpyrrolidone used in this invention has a weight average molecular weight (Mw) in the range of 40,000 to 60,000, more preferably 45,000 to 55,000, such as PVP-K30.

Specifically, the weight ratio of the blue dye to the solubilizer can range from 1:0.02 to 0.4, and more preferably from 1:0.1 to 0.4. Increasing the weight ratio of the blue dye to the solubilizer within this range can significantly improve the solubility of the blue dye in water. It is understood that this weight ratio range is not intended to limit the invention; any weight ratio range that achieves the effect of improving the solubility of the dye composition of the invention is within the spirit of the invention.

In one embodiment, the dye composition further includes a cosolvent, which is one of the groups consisting of soluble starch and glucose. The inventors have found through numerous experiments that adding a cosolvent to the dye composition helps to improve the solubility of the dye in water, and that selectively adding a cosolvent helps to maintain the increased solubility at a certain level. More specifically, high solubility and excellent colorfastness in water are important indicators for dyes. The factor affecting dye solubility is the degree of purification of the dye itself. Desalination and purification can be achieved by adding a large amount of cold water to the blue raw material solution, with the ratio of blue raw material solution to cold water ranging from 1:10 to 1:30. This can remove at least 65% of the salts in the blue raw material solution, and even at least 80%. Therefore, increasing the degree of purification is beneficial for improving dye solubility. Further adding a solubilizer can further increase the dye's solubility in water, and adding a co-solvent can maintain the increased solubility at a certain level, achieving the effect of improving/maintaining solubility.

In one embodiment, the amount of the cosolvent is 5 to 65 parts by weight relative to 100 parts by weight of the acid dye, and the amount of the cosolvent is 35 to 95 parts by weight. The relative amounts of the cosolvent and the cosolvent have different effects on the solubility of the dye, and the detailed content ratios, i.e., the specific effects on solubility, will be described in the embodiments at the end of this document.

In one embodiment of the present invention, the dye composition further includes an acid dye. Adding the acid dye to the dye composition of the present invention not only further increases solubility but also expands the color gamut of the dye composition, thereby increasing its market applicability.

Specifically, the weight ratio of the blue dye to the acid dye can be in the range of 1:0.04 to 0.2. It is understood that this weight ratio range is not intended to limit the invention, and any weight ratio range that does not affect the effect of the dye composition of the invention on improving solubility is not contrary to the spirit of the invention.

On the other hand, the present invention also provides a dye composition prepared according to the method for manufacturing dye compositions as described above. The dye composition includes a blue dye, a solubilizer, and a cosolvent, and optionally also includes an acid dye.

Although the blue dye with chemical formula (1) used in the dye composition of this invention has a bright royal blue color and excellent color fastness, its solubility in water is poor (less than 5 g/L), which will cause uneven dyeing and staining spots when used for dyeing. Chemical formula (1)

Therefore, the inventors of this application are committed to improving the solubility of blue dyes with chemical formula (1) in water while maintaining their excellent color fastness, so as to solve the problem of staining spots during dyeing.

[Blue dye]

The dye composition of this invention includes a blue dye comprising a dye with the structure of the above-described chemical formula (1). Although the dye with the structure of chemical formula (1) is presented in this specification as a sodium sulfonate salt, it is well known to those skilled in the art that it can also be presented in a free state (sulfonate ion) or other forms. Furthermore, the sodium salt of the structure of chemical formula (1) can also be replaced by other metal salts, such as alkali metal salts like lithium.

The dye with chemical formula (1) used in this invention is a known compound that can be prepared by methods known in the literature, such as the method described in US Patent 2,008,796A. Specifically, for example, C.I. Acid Blue 129 can be reacted with formaldehyde to prepare the dye with chemical formula (1); commercially available compounds can also be used.

[Dissolving agent]

The solubilizer used in the dye composition of the present invention includes polyvinylpyrrolidone (PVP). By including this solubilizer, the dye composition of the present invention can significantly improve the solubility of blue dye in water, thereby greatly increasing the solubility of blue dye with chemical formula (1) in water from less than 5 g/L to more than 20 g/L; more preferably, the solubility can be more than 30 g/L; even more preferably, an excellent solubility effect of 50~70 g/L can be achieved.

Preferably, the polyvinylpyrrolidone used in this invention has a weight average molecular weight (Mw) in the range of 40,000 to 60,000, more preferably 45,000 to 55,000, such as PVP-K30.

Specifically, the weight ratio of blue dye to solvent can be in the range of 1:0.02 to 0.4, and preferably 1:0.1 to 0.4.

[Acid dyes]

The acid dyes used in the dye compositions of this invention include purple acid dyes, green acid dyes, or acid dyes of other colors. For example, purple acid dyes may include C.I. Acid Violet 48, and green acid dyes may include C.I. Acid Green 27. It is understood that the addition of any other acid dyes is not contrary to the spirit of this invention, provided it does not affect the effect of the dye compositions of this invention in improving solubility. Further adding acid dyes to the dye compositions of this invention can not only further increase solubility but also expand the color gamut of the dye compositions, thereby increasing their market applicability.

Specifically, the weight ratio of blue dye to acid dye can be in the range of 1:0.04 to 0.2, which can maximize the effect of increasing the color gamut of the dye composition.

[Cosolvent]

The cosolvent is a soluble starch, such as dextrin. In some embodiments, the cosolvent is glucose. In some embodiments, the cosolvent may even be omitted. If the function of a solubilizer is to increase the solubility of the dye, the effect of the cosolvent is to maintain the solubility of the dye at a certain level after the increase. Specifically, the weight ratio of blue dye to cosolvent can range from 1:0.1 to 0.7, which most stably maintains the solubility of the dye at a certain level (e.g., greater than 30 g/L).

[Additive]

Without affecting the effect of improving the solubility of the dye composition of the present invention, the dye composition of the present invention may include additives. Additives include fillers or other auxiliaries, such as colorants, ultraviolet absorbers, antibacterial agents, antifungal agents, antistatic agents, flame retardants, etc.

In application, the dye composition of this invention can be used for dyeing according to conventional methods. For example, in the immersion dyeing method, the fabric (nylon cloth) is introduced into an aqueous dye bath with the pH value maintained between 3.5 and 6, and then the aqueous dye bath is steadily heated from room temperature to 100°C. The dye bath and fabric are then kept at this temperature for 40 minutes, cooled, and the unfixed dye is rinsed off the fabric.

Aqueous dye baths may include an aqueous solution of 0.1% by weight of the dye composition, and further, pH auxiliaries such as ammonium sulfate or leveling agents may be added. It is understood that aqueous dye baths can use different concentrations of dye compositions or add different co-solvents and additives as needed.

Examples of preparation of dye compositions

Dye G-1:

Solvent: Polyvinylpyrrolidone (PVP-K30)

Cosolvent: Soluble starch (dextrin) or glucose

Acid dye: C.I. Acid Violet 48

Preparation Example 1: Take 100 parts by weight of dye G-1, 10 parts by weight of polyvinylpyrrolidone and 90 parts by weight of soluble starch, pour them into a mixer and mix evenly to form dye composition 1.

Preparation Example 2: Take 100 parts by weight of dye G-1, 20 parts by weight of polyvinylpyrrolidone and 80 parts by weight of soluble starch, pour them into a mixer and mix evenly to form dye composition 2.

Preparation Example 3: Take 100 parts by weight of dye G-1, 30 parts by weight of polyvinylpyrrolidone and 70 parts by weight of soluble starch, pour them into a mixer and mix evenly to form dye composition 3.

Preparation Example 4: Take 100 parts by weight of dye G-1, 40 parts by weight of polyvinylpyrrolidone and 60 parts by weight of soluble starch, pour them into a mixer and mix evenly to form dye composition 4.

Preparation Example 5: Take 100 parts by weight of dye G-1, 50 parts by weight of polyvinylpyrrolidone and 50 parts by weight of soluble starch, pour them into a mixer and mix evenly to form dye composition 5.

Preparation Example 6: Take 100 parts by weight of dye G-1, 40 parts by weight of polyvinylpyrrolidone and 60 parts by weight of soluble starch, pour them into a mixer and mix evenly to form dye composition 6.

Preparation Example 7: Take 100 parts by weight of dye G-1, 40 parts by weight of polyvinylpyrrolidone and 60 parts by weight of glucose, pour them into a mixer and mix evenly to form dye composition 7.

Preparation Example 8: Take 100 parts by weight of dye G-1, 50 parts by weight of polyvinylpyrrolidone and 50 parts by weight of glucose, pour them into a mixer and mix evenly to form dye composition 8.

Preparation of Comparative Example 1: Take 100 parts by weight of dye G-1 and 4 parts by weight of soluble starch, pour them into a mixer and mix evenly to form Comparative Composition 1.

Preparation of Comparative Example 2: Take 100 parts by weight of dye G-1, 10 parts by weight of C.I. Acid Violet 48 and 4 parts by weight of soluble starch, pour them into a mixer and mix evenly to form Comparative Composition 2.

The composition ratios and water solubility results of the dye compounds 1-9 and comparative compounds 1-2 prepared by the above preparation examples 1-9 and preparation comparative examples 1-2 are shown in Table 1.

Table 1 (parts by weight) Dye G-1 Cosolvent Cosolvent (dextrin) Co-solvation agent (glucose) Solubility (g/l) Dye Composition 1 100 10 90 / 30 Dye Composition 2 100 20 80 / 40 Dye Composition 3 100 30 70 / 50 Dye Composition 4 100 40 60 / 55 Dye Composition 5 100 50 50 / 60 Dye Composition 6 100 60 40 / 70 Dye Composition 7 100 40 / 60 50 Dye Composition 8 100 50 / 50 55 Compare composition 1 100 0 4 / 5 Comparative composition 2 100 0 4 / 5

Take 1g of the dye composition prepared in the above preparation examples 1-8 or comparative examples 1-2 and place it in a 150ml beaker. Add 100ml of distilled water at 85℃ and stir until dissolved. Prepare a dye solution with a dyeing concentration of 1% and a liquor ratio of 1:30. Place nylon Taffeta in the beaker and heat it to 100℃ at a rate of 1.5℃/min. Keep it at this temperature for 45 minutes. After cooling, remove the dyed nylon fabric, wash it with water, dry it, and then test it.

The dyed nylon fabric was directly visually inspected to determine whether there were dye spots. X indicates obvious dye spots, ○ indicates no obvious dye spots under visual inspection, and ◎ indicates uniform color and no dye spots under visual inspection. The test results are shown in Table 2.

Table 2 staining spots Dye Composition 1 ○ Dye Composition 2 ◎ Dye Composition 3 ◎ Dye Composition 4 ◎ Dye Composition 5 ◎ Dye Composition 6 ◎ Dye Composition 7 ◎ Dye Composition 8 ◎ Compare composition 1 X Comparative composition 2 X

As can be seen from the above embodiments and comparative examples, by including polyvinylpyrrolidone, the dye composition can significantly improve the solubility of the blue dye with the chemical formula (1) while maintaining excellent color fastness, thereby solving the problem that the blue dye is prone to staining spots during dyeing.

Compared to the prior art, in the manufacturing method of the dye composition of the present invention, after removing more impurities and more complex salts from the dye raw material through step S20, it helps to ensure that the dye composition manufactured by the manufacturing method of the present invention can still maintain a solubility of 30 g/L to 70 g/L. In this way, while maintaining a certain solubility, it can have better color fastness and coloring rate, while avoiding the formation of soap scum due to the complexity of salt components, or making it easier to remove soap scum by chemical means when it does form due to its simple composition. Furthermore, the method for manufacturing the dye composition of the present invention involves purifying the dye raw material solution with a large amount of cold water to remove a large amount of salts contained in the dye raw material solution, so that the salt content in the blue raw material solution treated by the desalination and purification process is significantly lower than the salt content in the blue raw material solution that has not undergone the desalination and purification process. A cosolvent is added to improve the solubility of the dye, and a cosolvent may be selectively added to maintain the solubility of the dye at a certain level. In other words, desalting the dye raw material solution for purification yields a highly purified dye raw material solution, which improves the dye's solubility. The solubilizer and co-solvent further enhance and maintain the dye's solubility, thereby increasing the dye's color strength. This reduces the amount of dye used, helps lower the concentration of dyeing residue and heavy metal residue, and further reduces environmental harm and industrial process costs, achieving energy conservation, carbon reduction, and environmental sustainability. More importantly, the desalting purification process in the dye composition manufacturing method of this invention eliminates the need for lengthy dye grinding, avoiding the problem of heavy metal residue in the dye after grinding by using a mill to grind dye molecules into smaller particles.

Although several preferred embodiments have been disclosed in this invention, they are not intended to limit the invention, but only to enable those skilled in the art to clearly understand the contents of this specification. Any person skilled in the art can make various modifications, substitutions and alterations without departing from the spirit and scope of this invention; therefore, the scope of protection of this invention shall be determined by the appended claims.

S10~S40: Steps

Figure 1 is a flowchart illustrating the manufacturing method of the dye composition provided in an embodiment of the present invention.

S10~S40: Steps

Claims (8)

A method for manufacturing a dye composition, the method comprising the following steps: Step S10: providing a blue dye raw material; Step S20: adding water to the blue dye raw material to form a blue raw material solution, and subjecting the blue raw material solution to a desalination and purification process, wherein the desalination and purification process comprises mixing the blue raw material solution with water in a ratio between 1:5 and 1:100 to carry out desalination and purification, such that the salt content in the blue raw material solution treated by the desalination and purification process is less than 35% of the salt content in the blue raw material solution not treated by the desalination and purification process, thereby reducing the salt content in the blue raw material solution treated by the desalination and purification process to less than 35 wt%; Step S30: Dry the purified blue raw material solution to form a blue dye; and Step S40: Mix the blue dye with a cosolvent and a cosolvent to obtain the dye composition; wherein the cosolvent is dextrin or glucose. The method of manufacturing the dye composition as described in claim 1, wherein the blue dye comprises the structure of the following chemical formula (1), and the cosolvent comprises polyvinylpyrrolidone; Chemical formula (1). The method for manufacturing the dye composition as described in claim 1, wherein the amount of the cosolvent is 5 to 65 parts by weight relative to 100 parts by weight of the blue dye, and the amount of the cosolvent is 35 to 95 parts by weight. The method for manufacturing the dye composition as described in claim 1, wherein the dye composition further comprises an acid dye. The method for manufacturing the dye composition as described in claim 1, wherein the weight ratio of the blue dye to the cosolvent is in the range of 1:0.02 to 0.4. The method for manufacturing the dye composition as described in claim 4, wherein the weight ratio of the blue dye to the acid dye is in the range of 1:0.04 to 0.2. The method for manufacturing the dye composition as described in claim 1, wherein in step S20, the desalination purification process is carried out by adding cold water to the blue raw material solution, wherein the ratio of the blue raw material solution to the cold water is in the range of 1:10 to 1:30. A dye composition prepared according to the method for manufacturing a dye composition as described in claims 1 to 7.