Decolorizing composition, decolorizing method, and decolorizing apparatus

Abstract

The dyed textile media is properly decolorized. [Solution] The decolorizing composition is used to decolorize textile media dyed with a dyeing material containing a sublimation dye, such as a sublimation dye or a sublimable disperse dye. The decolorizing composition contains a chain compound containing one hydroxyl group and multiple alkoxy or ether groups as an active ingredient.

Description

Technical Field

[0001] The present invention relates to a decolorizing composition, a decolorizing method, and a decolorizing apparatus used for decolorizing media colored with dyes.

Background Art

[0002] Patent Document 1 discloses a method for decolorizing polyester fibers colored with dyes.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, the vapor of an alcohol ether solvent is used to extract the dye from the polyester fibers colored with the dye, thereby decolorizing the polyester fibers. However, if there is a dark-colored region in the colored part, the decolorization of such a region may be insufficient. Therefore, it is required to be able to appropriately decolorize not only polyester but also fibrous media (fibrous media) colored with dyes.

Means for Solving the Problems

[0005] The present inventor has earnestly studied a method for removing the dye from a fibrous medium dyed with a dyeing material containing a sublimable dye such as a sublimation dye or a disperse dye having sublimability, thereby decolorizing the fibrous medium. As a result, it has been found that by using a decolorizing composition having a specific molecular structure for a fibrous medium dyed with a dyeing material containing a sublimable dye, even if the colored part contains a dark-colored region, the fibrous medium can be appropriately decolorized.

[0006] One aspect of this invention is a decolorizing composition used for decolorizing a fibrous medium dyed with a dyeing material containing a sublimable dye such as a sublimation dye or a disperse dye having sublimability, which is a decolorizing composition containing, as an active ingredient, a chain compound containing one hydroxy group and a plurality of alkoxy groups or ether groups.

[0007] With this configuration, even if a dark-colored region is included in the colored portion, the fibrous medium can be appropriately decolorized.

[0008] One aspect of this invention is a decolorizing composition used for decolorizing a fibrous medium dyed with a dyeing material containing a sublimable dye such as a sublimation dye or a disperse dye having sublimability, which is a decolorizing composition containing, as active ingredients, a chain compound containing one hydroxy group and a plurality of alkoxy groups or ether groups, and a surfactant.

[0009] With this configuration, even if a dark-colored region is included in the colored portion, the fibrous medium can be appropriately decolorized. In addition, by including a surfactant, the number of times and the time of the decolorization treatment using the decolorizing composition can be reduced as compared with the case where no surfactant is included. Thereby, the colored fibrous medium can be appropriately decolorized. Furthermore, when the decolorization treatment is performed, shrinkage or the like occurs in the fibrous medium due to the drying treatment after decolorization. By including a surfactant, the number of times or the treatment time of the decolorization treatment can be reduced, so that the degree of shrinkage of the fibrous medium due to the decolorization treatment can be reduced.

[0010] One aspect of this invention is (3) The surfactant is at least one of an anionic surfactant and a nonionic surfactant, An anionic surfactant is at least one of the following surfactants: sulfonic acid-based, phosphoric acid-based, lauric acid-based, or dodecylic acid-based. The nonionic surfactant was a decolorizing composition comprising at least one of the following: a surfactant having a hydroxyl group that does not ionically dissociate in water as a hydrophilic group, and a surfactant having an ether bond as a hydrophilic group.

[0011] With this configuration, even if the colored area includes dark-colored regions, the fibrous media can be properly decolorized.

[0012] One aspect of this case is, (4) The chain compound is at least one selected from the following: 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-isobutoxyethoxy)ethanol, 2-[2-(butoxyethoxy)ethoxy]ethanol, 2-[2-(methoxyethoxy)ethoxy]ethanol, 2-(2-hexyloxyethoxy)ethanol

[0013] With this configuration, even if the colored area includes dark-colored regions, textile media dyed with a dyeing material containing sublimation dyes, such as sublimation dyes or sublimable disperse dyes, can be appropriately decolorized.

[0014] One aspect of this case is, (5) A method for decolorizing a textile media dyed with a dyeing material containing a sublimation dye such as a sublimation dye or a disperse dye having sublimation properties, The decolorizing composition used for decolorizing the aforementioned fibrous media is: It contains a chain-like compound as an active ingredient, which includes one hydroxyl group and multiple alkoxy or ether groups. The decolorization method involves immersing the fibrous media in the decolorization composition and heating it at a temperature higher than the fiber opening temperature at which the molecular chains or intermolecular forces of the fibers loosen, or immersing it in the decolorization composition heated at a temperature higher than the fiber opening temperature.

[0015] With this configuration, the dye held in the gaps between the molecular chains of the fibers constituting the fiber media can be transferred from the fiber media to the decolorizing composition, thereby decolorizing the fiber media.

[0016] One aspect of this case is, (6) Apparatus for decolorizing a textile media dyed with a dyeing material containing a sublimation dye such as a sublimation dye or a sublimation disperse dye, A decolorizing composition used for decolorizing the aforementioned fibrous media, and a container for containing the aforementioned fibrous media. The method includes heating means for heating the decolorization composition to a temperature higher than the fiber opening temperature at which the molecular chains or intermolecular forces of the fibers are relaxed. The decolorizing composition used for decolorizing the aforementioned fibrous media is a decolorizing apparatus that contains a chain-like compound comprising one hydroxyl group and multiple alkoxy or ether groups as an active ingredient.

[0017] With this configuration, the dye held in the gaps between the molecular chains of the fibers constituting the fiber media can be transferred from the fiber media to the decolorizing composition, thereby decolorizing the fiber media. [Effects of the Invention]

[0018] According to the present invention, textile media dyed with a dyeing material containing a sublimation dye, such as a sublimation dye or a sublimation-capable disperse dye, can be appropriately decolorized. [Brief explanation of the drawing]

[0019] [Figure 1] This is a schematic diagram illustrating the configuration of the decolorization apparatus. [Modes for carrying out the invention]

[0020] Hereinafter, embodiments of the present invention will be described, including a decolorizing composition used when decolorizing a fibrous media (a fibrous media), and a method for decolorizing a fibrous media using the decolorizing composition. Here, the textile media used for decolorization using the decolorization composition is a textile media dyed with a dyeing material containing a sublimation dye, such as a sublimation dye or a sublimable disperse dye. In other words, it is a textile media dyed with a dyeing material containing a sublimable dye. Hereafter, textile-based media (textile-based media) may be collectively referred to as Media M.

[0021] [Dyeing materials] In this specification, "dyeing material" means a dyeing material containing sublimation dyes, such as sublimation dyes or sublimable disperse dyes. Sublimation dyes mean conventionally known dyes that have sublimation properties. Sublimable disperse dyes mean organic compounds that are poorly soluble in water and have the property of changing directly from a solid to a gas when heated (sublimation). Furthermore, "sublimation-possessing dyes" refer to dyes that can dye fibers by vaporizing (sublimating) from a solid dye under predetermined temperature and pressure conditions, such as sublimation dyes or sublimation-possessing disperse dyes, and then adhering to the fibers. Furthermore, dyeing refers to the process of expressing colors, patterns, letters, or designs on fibers using methods such as hand dyeing, screen printing, digital printing, inkjet printing, or transfer printing.

[0022] [Media M] Media M is not particularly limited as long as it is made of fibers that can be dyed using a dyeing material containing sublimable dyes. Examples of fibers that can be dyed using dyeing materials containing sublimation dyes include fabrics (woven, knitted, etc.) made of hydrophobic fibers such as polyester fibers, acetate fibers, and polyamide fibers. Fabrics made by blending, twisting, weaving, or knitting these materials with other types of synthetic or natural fibers are also acceptable. In this embodiment, media M may particularly include polyester fibers. Furthermore, it is preferable that the polyester fibers are polyester fibers produced by a condensation reaction between a dicarboxylic acid having an aromatic ring and a diol. Media M, dyed using a dyeing material containing sublimation dyes, is a media M dyed using the principle that the media M is heat-treated at a predetermined temperature to create gaps between the molecular chains of the fibers constituting the media M, and the sublimated dye molecules enter and are captured (fixed) into these gaps between the molecular chains of the fibers, thereby dyeing the fibers. The heat treatment during dyeing is performed at a temperature higher than the fiber opening temperature (130°C), which is the temperature at which the gaps between the molecular chains of the fibers open, but lower than the melting point of the fibers. This temperature range is 180-220°C. The inventors of this case have diligently investigated how to decolorize the dyed media M by utilizing the reverse effect of this dyeing principle.

[0023] For example, if the fiber is polyester fiber, media M can be either plain woven or twill woven polyester yarn. Examples of polyester fabrics (media) include Tropical (100% polyester), Pongee (100% polyester), Smooth (100% polyester), Honeycomb (100% polyester), and Lycra (registered trademark) (15% polyurethane - 85% polyester). Furthermore, the media may also be made from recycled polyester yarn. For example, it may be pongee woven using recycled polyester yarn (recycled pongee). Here, tropical and pongee are fabrics used for advertising and promotional tools such as roller blinds, pennants, and banners.

[0024] Examples of media M dyed with sublimation dyes include media M on which information is printed using sublimation transfer technology, media M dyed with sublimation dyes, and media M on which information is printed using sublimation transfer technology on media M dyed with sublimation dyes. Here, "information" in this specification does not mean only the "patterns" or "designs" of printed images, but also includes letters, pictures, and other elements.

[0025] For example, information is printed using a conventionally known inkjet printing device. Inkjet printers are equipped with process color ink sets. Process colors are yellow (Y), magenta (M), cyan (C), and black (K), which are the basic colors used in full-color printing. In this embodiment, the ink set of the printing device may include, in addition to magenta (M) ink, at least one of yellow (Y) ink, cyan (C) ink, and black (K) ink. The ink set may also further include green, purple, and orange inks, which are complementary colors to the basic color inks.

[0026] [Decolorizing composition] The decolorizing composition is a solvent component used when decolorizing media M. The decolorizing composition is a liquid compound having a boiling point higher than the fiber opening temperature of the molecular chains of the fibers that make up media M. In the case of media M made of polyester, it is a liquid compound having a boiling point higher than the fiber opening temperature of the polyester molecular chains. The inventors of this case have diligently investigated a method for decolorizing a fabric media M, particularly polyester fabric media M, that has been dyed using a dyeing material containing a sublimation dye, by removing the dye. As a result, we found that polyester-based media M, dyed with sublimation dyes, can be decolorized without the need for absorbents such as paper or cloth by using a decolorizing composition containing a compound with a specific molecular structure. Specifically, we found that by immersing media M, a fabric dyed with a dyeing material containing a sublimable dye, in the decolorization composition described below and heating it, the sublimable dye migrates to the decolorization composition, and media M is decolorized. In other words, we found that the decolorization of media M can be performed without requiring a separate absorbent to absorb the dye in addition to the decolorization composition.

[0027] Furthermore, after decolorization, when the decolorizing composition remaining on media M is removed and media M is heat-dried, a decolorizing composition was found that is less likely to cause shrinkage in the dried media M. This led to the discovery that dyed media M could be decolorized without shrinking or other damage, and then recycled.

[0028] The decolorizing composition is a linear compound having a hydroxyl group (-OH) and multiple alkoxy groups (or ether groups). More specifically, it is a solvent component containing at least one of the following compounds as an active ingredient: 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-isobutoxyethoxy)ethanol, 2-[2-(butoxyethoxy)ethoxy]ethanol, 2-[2-(methoxyethoxy)ethoxy]ethanol, or 2-(2-hexyloxyethoxy)ethanol.

[0029] The boiling point of 2-(2-ethoxyethoxy)ethanol (196°C) is higher than the fiber opening temperature at which the molecular chains of the fiber loosen. 2-(2-ethoxyethoxy)ethanol has a hydroxyl group at one end and an ethoxy group at the other, with one ether bond between the hydroxyl and ethoxy groups.

[0030] 2-(2-butoxyethoxy)ethanol is a linear compound having a hydroxyl group (-OH) and multiple alkoxy groups (or ether groups). The boiling point of 2-(2-butoxyethoxy)ethanol (230°C) is higher than the fiber opening temperature at which the molecular chains of fibers loosen. 2-(2-butoxyethoxy)ethanol has a hydroxyl group at one end and a butoxy group at the other, with one ether bond between the hydroxyl and butoxy groups.

[0031] The boiling point of 2-(2-isobutoxyethoxy)ethanol (230°C) is higher than the fiber opening temperature at which the molecular chains of the fiber loosen. 2-(2-isobutoxyethoxy)ethanol has a hydroxyl group at one end and an isobutoxy group at the other, with one ether bond between the hydroxyl group and the isobutoxy group.

[0032] The boiling point of 2-[2-(butoxyethoxy)ethoxy]ethanol (280°C) is higher than the fiber opening temperature at which the molecular chains of fibers loosen. 2-[2-(butoxyethoxy)ethoxy]ethanol has a hydroxyl group at one end and a butoxy group at the other, with two ether bonds between the hydroxyl and butoxy groups.

[0033] The boiling point of 2-[2-(methoxyethoxy)ethoxy]ethanol (249°C) is higher than the fiber opening temperature at which the molecular chains of the fiber loosen. 2-[2-(methoxyethoxy)ethoxy]ethanol has a hydroxyl group at one end and a methoxy group at the other, with two ether bonds between the hydroxyl and methoxy groups.

[0034] The boiling point of 2-(2-hexyloxyethoxy)ethanol (260°C) is higher than the fiber opening temperature at which the molecular chains of fibers loosen. 2-(2-hexyloxyethoxy)ethanol has a hydroxyl group at one end and a hexyloxy group at the other, with one ether bond between the hydroxyl group and the hexyloxy group.

[0035] The decolorizing composition may contain these exemplified compounds (solvent components) individually. The decolorizing composition may contain at least two of these compounds in any proportion. In addition to these compounds, the decolorizing composition may contain water, other organic solvents, additives, and surfactants.

[0036] [Surfactants] The inventors of this case have found that when removing dye from media M, which is made of fibers (including polyester fibers) dyed with sublimation dyes, by adding a surfactant to the above-mentioned decolorization composition, the media can be properly decolorized even if it has dark areas or areas with a large amount of printing that are prone to color retention before decolorization. Furthermore, we found that adding a surfactant to the above-mentioned decolorization composition can reduce the number of times the media needs to be decolorized (decolorization cycles) or the decolorization processing time. Surfactants are thought to act as penetrants, improving the polarity and wettability of the solvent relative to the fiber, thereby making it easier for the solvent to penetrate the fiber. In other words, surfactants facilitate the penetration of the solvent deep into the fiber, making it easier for fiber molecules located in the deepest parts of the fiber, furthest from the surface, to reach the fiber opening temperature. They are also thought to play a role in making it easier for dyes attached to the gaps between fiber molecules to be extracted by the solvent. In short, surfactants adjust the intermolecular attractive forces between the fiber, solvent, and dye.

[0037] The surfactant is at least one of the following: anionic surfactant, cationic surfactant, or nonionic surfactant. Multiple types of surfactants included in these may be mixed and used. Here, the anionic surfactant is preferably at least one of the following: a sulfonic acid (sulfosuccinate) type, a phosphoric acid type, a lauric acid type, or a dodecylic acid type surfactant. The nonionic surfactant is preferably at least one of the following: a surfactant having a hydroxyl group that does not ionically dissociate in water as a hydrophilic group, and a surfactant having an ether bond as a hydrophilic group. More specifically, it is at least one of the following: sodium diethylhexyl aerosol sulfosuccinate, polyoxyethylene (23) lauryl ether, polyoxyethylene (10) octylphenyl ether, sodium monododecyl phosphate, sodium laurate, sodium dodecyl sulfate, lauryltrimethylammonium chloride, and sorbitan monopalmitate.

[0038] Sodium diethylhexyl aerosol sulfosuccinate is the sodium salt of the diester of sulfosuccinic acid and 2-ethylhexyl alcohol. Sodium diethylhexyl aerosol sulfosuccinate is an anionic surfactant classified as an alkyl sulfonate. Sodium diethylhexyl aerosol sulfosuccinate is readily soluble in organic solvents and oils.

[0039] Polyoxyethylene(23) lauryl ether is an ether obtained by etherically bonding ethylene oxide (approximately 23 moles) to lauryl alcohol. Polyoxyethylene(23) lauryl ether is a nonionic surfactant classified as an ethylene oxide condensation type polyoxyethylene alkyl ether. Polyoxyethylene(23) lauryl ether is readily soluble in water.

[0040] Polyoxyethylene(10) octylphenyl ether is a type of polyoxyethylene alkylphenyl ether. Polyoxyethylene(10) octylphenyl ether is a nonionic surfactant that does not dissociate into ions when dissolved in water. Polyoxyethylene(10) octylphenyl ether is readily soluble in water, ethanol, and acetone.

[0041] Sodium monododecyl phosphate is a sodium phosphate salt. When dissolved in water, sodium monododecyl phosphate is an anionic surfactant in which the hydrophobic portion dissociates into a negative ion. Sodium monododecyl phosphate is readily soluble in water.

[0042] Sodium laurate is the sodium salt of lauric acid, a fatty acid derived from coconuts, and is classified as a soap. Sodium laurate is an anionic surfactant. Sodium laurate is readily soluble in water.

[0043] Sodium dodecyl sulfate is an anionic surfactant. It is readily soluble in water and alcohol.

[0044] Lauryltrimethylammonium chloride is a cationic surfactant. It is readily soluble in water.

[0045] Sorbitan monopalmitate is a nonionic surfactant. Sorbitan monopalmitate is readily soluble in organic solvents and oils.

[0046] [Decolorization test] A decolorization test was performed using a decolorizing composition containing the above-mentioned compounds and a surfactant, with a stained test media M. (i) Test media M Using a printing device (Mimaki Engineering Co., Ltd.: TS330 (product name)), a color chart test pattern was printed on transfer paper (Mimaki Engineering Co., Ltd.: TRS95 (product name)) with sublimation ink (Mimaki Engineering Co., Ltd.: Sb411 (product name)). The color chart test pattern was a rectangular test pattern measuring 600 cm wide and 600 cm long, printed in 10-100% gradation for each color using primary colors (colors printed using only one of each of cyan (C), magenta (M), yellow (Y), and black (K)), secondary colors (colors printed using two of the CMYK colors), tertiary colors (colors printed using three of the CMYK colors), and black printed using all CMYK colors (black printed by dropping the four color inks in predetermined proportions, hereinafter referred to as 4C100%). Using a transfer machine (manufactured by Montiantonio), the test pattern was transferred from the printed transfer paper onto a polyester (tropical, recycled pongee) media to create test media M. (ii) Disperse dyes (water-based sublimation inks) As an example of a dyeing material containing disperse dyes, we have used Mimaki Engineering Co., Ltd.'s water-based sublimation ink Sb411 (product name) as an example. However, any disperse dye can be appropriately selected as long as the pigment molecules contained in the disperse dye can be incorporated into the gaps in the molecular chains of the polyester fibers of media M, thereby dyeing or coloring media M.

[0047] (iii) Decolorizing composition For the decolorization test, the following decolorization compositions A to C were prepared. TIFF2026108488000001.tif30158

[0048] Here, NewSolve UC is a mixed solution mainly containing dimethyl succinate, dimethyl glutarate, and dimethyl adipate, and is another decolorizing composition prepared for comparison with decolorization using ethyl carbitol. In addition, 1 part by weight each of sodium diethylhexyl aerosol sulfosuccinate and polyoxyethylene (23) lauryl ether was added per 100 parts by weight of the decolorizing composition.

[0049] (iv) Decolorization test In the decolorization test, three steps are performed on the test media M: a decolorization step, a rinsing step, and a drying step. One cycle of the decolorization, rinsing, and drying processes corresponds to "one decolorization" in the following explanation. Therefore, when it is written as "three decolorizations," it means that the cycle of decolorization, rinsing, and drying was performed three times.

[0050] <Decolorization process> The decolorization process was carried out according to the following procedure. (a) The test media M, on which the test pattern is printed, is immersed in the decolorizing composition (300 g) in the sample flask (1000 ml). (b) The sample flask is attached to a rotary vaporizer, and the lower part of the sample flask is immersed in a constant temperature bath containing a heat transfer medium heated to a predetermined temperature. At this time, the sample flask is positioned so that the upper edge of the decolorizing composition in the sample flask is below the liquid level of the heat transfer medium (oil) in the constant temperature bath. (c) The sample flask is heated with the heat transfer medium while rotating it at atmospheric pressure using the rotary vaporizer.

[0051] In this case, when the decolorizing composition is ethyl carpitol, the heating in (c) above was carried out at 180°C for 5 minutes. Furthermore, in the case of NewSolve UC, a comparative decolorizing composition, the heating in (c) above was performed at 160°C for 5 minutes. NewSolve UC is a mixture mainly composed of dimethyl succinate, dimethyl glutarate, and dimethyl adipate.

[0052] <Rinsing process> The rinsing process was carried out according to the following procedure. (a) After the decolorization process is complete, the media M is immersed in the decolorization composition in another sample flask. The decolorization composition used here is the same decolorization composition used in the decolorization process, but unused. (b) After attaching the sample flask to the rotary vaporizer, the lower part of the sample flask is immersed in a constant temperature bath that stores a heat transfer medium heated to a predetermined temperature. (c) Using the rotary vaporizer, the sample flask is rotated at atmospheric pressure while the sample flask is heated with the heat transfer medium, and the decolorization composition and media M in the sample flask are heated at 160°C for 1 minute while stirring.

[0053] <Drying process> The drying process was carried out according to the following procedure. (a) After the rinsing process was completed, the media M was placed on a conveyor belt and passed through a drying chamber exposed to 180° hot air to dry the media M. The time required for passing through was set to 1 minute.

[0054] [Evaluation] The evaluation of the decolorizing composition was conducted for the following evaluation items. (I) Decolorization evaluation Using a color difference meter (manufactured by Konica Minolta Co., Ltd.: FD-7 (product name)), the L * (lightness), a * (red-green hue), and b * (yellow-blue hue) values of the medium M after the drying process and the comparative medium M were determined respectively.

[0055] As shown in Table 1 below, when decolorizing the dark color area (K100%) in the medium M (tropical, recycled sponge) using the decolorizing compositions A to C, the a * value and the b * value change significantly compared to the measured values of the dark color area (K100%) of the medium before decolorization. For example, when decolorizing the medium (tropical) using the decolorizing composition B (ethyl carbitol), the L * value, a * value, and b * value changed by 3.66 (= 92.75 - 89.09), 2.30 (= 3.14 - 0.84), and 6.71 (= |-10.34 - (-3.63)|) respectively before and after decolorization.

[0056] [Table 1] <7]]

[0057] Here, as shown in Table 2 below, when decolorization is appropriately performed, the measured values of the dark color areas (K100%, 4C100%) of the medium after decolorization are closer to the measured values of the non-printing areas of the medium after decolorization. For example, when decolorizing the medium (tropical) using the decolorizing composition A (New Solv UC), the L * value, a * value, b * value of the K100% area and the L * [[ID=value, a * value, b * value of the background area, the differences (ΔL * , Δa* Δb * These values ​​are 0.07 (=90.91-90.84), 0.43 (=1.19-0.76), and 1.22 (=-2.08-(-3.30)), respectively. For example, when decolorizing media (tropical) using decolorizing composition B (ethyl carbitol), the L in the K100% region... * value, a * value, b * Value and L of the base area * value, a * value, b * Difference from the value (ΔL) * Δa * Δb * These values ​​are 0.49 (=89.58-89.09), -0.02 (=0.82-0.84), and 1.00 (=-2.63-(-3.63)), respectively. The inventor of this case measured the dark color region (K100%, 4C100%) of the media after decolorization (L * value, a * value, b * The value is the measured value (L) of the non-printed area on the decolorized media. * value, a * value, b * It was compared with the value. In particular, if the dye is not completely removed from the dark areas and remains on the media, a brownish (or yellowish) color tends to remain. Therefore, especially before and after bleaching, * Difference in value Δb * It is possible to determine whether the bleaching was performed properly from this. Also, the overall color fading is determined by the color difference (ΔE:L * value, a * value, b * It is possible to determine this from the overall color difference of the values. [Table 2]

[0058] Therefore, Δb * The values ​​and ΔE values ​​(overall color difference) were used as indicators to confirm whether the dark color areas (K100%, 4C100%) had been properly decolorized.

[0059] Table 3 below shows the results when decolorizing the dark color region (K100%, 4C100%) of media M (tropical, recycled pongee) using decolorizing compositions A to C. * The value and Δb * The values ​​were summarized. [Table 3]

[0060] [Evaluation Results] As shown in Table 3 above, regardless of media M, in both the dark color region (K100%, 4C100%), decolorization using the decolorizing composition (B: ethyl carbitol, C: ethyl carbitol + surfactant) results in a Δb difference compared to the comparative decolorizing composition (A: NewSolve UC). * We confirmed that the value of becomes smaller. For example, in the case of tropical plants, decolorizing the dark color region (K100%) results in Δb for the decolorizing composition (B: ethyl carpitol). * However, it is 1.09. In contrast, for the comparative decolorizing composition (A: NewSolve UC), Δb * The value is 1.43, and the Δb ratio is higher for the decolorizing composition (B: ethyl carbitol) than for the comparative decolorizing composition (A: Newsolve UC). * It is smaller than that.

[0061] Here, the inventors of this case diligently examined the measurement results of media M before and after decolorization, and found that Δb * We confirmed that when the value reaches "2.0" or higher, the difference in color becomes visible to the naked eye. Therefore, in order to detect the remaining dark color (for example, black), the b of the decolorized media M * The value and the b of media M2 for comparison. * The difference from the value (Δb) * ) and the difference Δb calculated * We decided to confirm whether decolorization was being performed properly by comparing it with the threshold Th. As an example, in this embodiment, "1.0" is adopted as the threshold Th, and the calculated difference (Δb* ) If Th is less than the threshold (Th > Δb * ) This was modified to determine if the bleaching process was performed correctly. The upper limit of the threshold Th can be set to any value up to "2.0" depending on the desired degree of decolorization.

[0062] Here, the b of media M2 for comparison * The value is the b of the area (non-printed area) in the media M after decolorization where no information is printed. * It is a value. Note that for comparison, b * The media used for measuring the values ​​may be any other media, as long as it is the same type of media that has been decolorized using the same decolorization composition and under the same decolorization conditions.

[0063] As an example, if the decolorized media is recycled sponge, a separate recycled sponge for comparison is prepared in addition to the recycled sponge used for evaluation in the decolorization test. Then, both the recycled sponge for evaluation and the recycled sponge for comparison are decolorized using the same decolorization composition and under the same decolorization conditions. In both the recycled sponge for evaluation and the recycled sponge for comparison after drying, b * You just need to find the values ​​for each and compare them.

[0064] As a result, it was confirmed that using the decolorizing compositions (B: ethyl carbitol, C: ethyl carbitol + surfactant) allows for proper decolorization even in areas with dark coloration.

[0065] (II) Decolorization time and number of decolorization cycles [Table 4]

[0066] Table 4 above summarizes the measured values ​​when decolorization was performed using the decolorizing composition (B: ethyl carpitol). The numbers "1," "2," and "3" indicate the number of times a 5-minute bleaching process was performed. "2" means that the 5-minute bleaching process was performed twice. "Continuous 15min" means that the bleaching process was performed continuously for 15 minutes.

[0067] In the case of tropical varieties, decolorization is performed using a decolorizing composition (B: ethyl carpitol), It was confirmed that the measured value fell below the threshold Th by performing decolorization at least once in the dark color region (K100%) and at least three times in the dark color region (4C). It was also confirmed that performing decolorization continuously for 15 minutes resulted in a lower measured value than performing decolorization in three separate steps. For example, in the dark color area (K100%), after decolorization three times, b * The value is "0.40", while the value after continuous decolorization for 15 minutes is b * The value was "0.32," indicating that the measurement was lower when bleaching was performed continuously for 15 minutes than when bleaching was performed in three separate steps.

[0068] In the case of recycled sponge, decolorization is performed using a decolorizing composition (B: ethyl carpitol), It was confirmed that the measured values ​​fell below the threshold Th by performing decolorization at least three times in the dark color region (K100%) and at least twice in the dark color region (4C). In the dark color region (K100%), it was confirmed that the measured value was lower when decolorization was performed continuously for 15 minutes rather than in three separate decolorization steps. In the dark color region (4C), it was confirmed that the measured value was lower when decolorization was performed in three separate steps rather than in a continuous 15-minute decolorization step.

[0069] (II) Number of bleaching cycles [Table 5] [Table 6]

[0070] Tables 5 and 6 above summarize the measured values ​​when decolorization was performed using decolorizing compositions (A: Newsolve UC, B: Ethyl Calpitol). The numbers "1," "2," and "3" represent the number of times the bleaching process was performed for 5 minutes. "2" means that the 5-minute bleaching process was performed twice.

[0071] When decolorization was performed using the decolorization composition (B: ethyl carbitol), it was confirmed that fewer decolorization cycles were required for both tropical and recycled sponge compared to when using the decolorization composition (A: NewSolve UC). For example, in the dark color region (K100%), when decolorization is performed using a decolorizing composition (B: ethyl carpitol), the result after decolorization twice is b * While the value is "0.71", if decolorization is performed using the decolorizing composition (A: NewSolve UC), it takes five decolorization steps to achieve the same value.

[0072] (II) Shrinkage evaluation [Table 7]

[0073] Table 7 above summarizes the measured values ​​of the change in media area (media shrinkage) when decolorization is performed multiple times using decolorizing compositions (A: NewSolve UC, B: Ethyl Carpitol). The numbers "1," "2," and "3" represent the number of times the bleaching process was performed for 5 minutes. "2" means that the 5-minute bleaching process was performed twice.

[0074] The shrinkage rate is calculated using the area R1 of the media before decolorization and the area R2 of the media after decolorization and drying, based on the following formula (1). Shrinkage rate (%) = (R1 - R2) / R1 × 100 ... (1)

[0075] From Table 7 above, it was confirmed that in both tropical and recycled pongee, decolorization using decolorization composition (A: NewSolve UC) resulted in less media shrinkage compared to decolorization using decolorization composition (B: Ethyl Carpitol).

[0076] As can be seen from the results of the decolorization compositions (B: ethyl carbitol, C: ethyl carbitol + surfactant) shown in Table 3 above, it was confirmed that decolorization in the dark color region (K100%, 4C100%) can be performed with fewer decolorization cycles using the decolorization compositions (B: ethyl carbitol, C: ethyl carbitol + surfactant) than with the decolorization composition (A: NewSolve UC). Therefore, even considering shrinkage after decolorization, it was confirmed that the decolorization compositions (B: ethyl carbitol, C: ethyl carbitol + surfactant) can be appropriately used as substitutes for the decolorization composition (A: NewSolve UC).

[0077] In the above-described embodiment, an example was given in which the decolorization step and the rinsing step are carried out by immersing the sample in a decolorization composition (300g) in a different sample flask (1000ml), a so-called batch method. For example, the process may be carried out in a continuous manner, with a first tank containing the decolorizing composition used in the decolorization process and a second tank containing the decolorizing composition used in the rinsing process, so that the media passes through them in sequence.

[0078] Figure 1 is a schematic diagram illustrating the configuration of a decolorization apparatus 1 used when decolorizing media M using a decolorization composition. Figure 1(a) shows the apparatus configuration for batch-type decolorization. The batch-type decolorization apparatus 1 includes a container 2 for storing the decolorization composition S, a heating device 3 for heating at least one of the decolorization composition S supplied to the container 2 and the container 2, and an air-drying device 4 (drying device) for drying the decolorized media M. In the decolorization apparatus 1 shown in Figure 1(a), a container 2 for the decolorization process and a container 2 for the rinsing process are provided. The decolorization composition S is stored in the container 2.

[0079] The decolorization of the media M, which is the object to be decolorized, is carried out for a predetermined time while controlling the heating device 3 so that the temperature of the media M in contact with the decolorization composition S is at least the fiber opening temperature. It is preferable to stir the decolorization composition S and media M in the container 2 during this process. The rinsing of the decolorized media M is performed by placing the decolorized media M into another container 2 containing the decolorizing composition S and rinsing for a predetermined time. It is preferable to stir the decolorizing composition S and media M in container 2 during this process. The drying of the media M after rinsing occurs as the media M passes through the air-drying device 4'.

[0080] Figure 1(b) shows the apparatus configuration for continuous decolorization. The decolorization apparatus 1' for continuous decolorization is equipped with a container 2' for storing the decolorization composition S and an air drying apparatus 4' (drying apparatus) for drying the decolorized media M, along the conveying path of the conveyor V. In the decolorization apparatus 1' shown in Figure 8(b), a container 2' for the decolorization process and a container 2' for the rinsing process are provided. The decolorization composition S is stored in the container 2'. The container 2' is equipped with a heating device 3 that heats at least one of the decolorization composition S supplied to the container 2' and the container 2' itself.

[0081] The media M, which is the object to be decolorized, is supported by a conveyor V and passes sequentially through a container 2' for the decolorization process, a container 2' for the rinsing process, and an air-drying device 4' for the drying process. Decolorization of media M occurs as media M passes through container 2 containing decolorization composition S. Rinsing of decolorized media M occurs as decolorized media M passes through another container 2' containing decolorization composition S. Drying of rinsed media M occurs as rinsed media M passes through air drying device 4'.

[0082] The drying process may also be carried out by using a press device to press-heat the rinsed media M at a third predetermined temperature higher than the fiber opening temperature.

[0083] As described above, the decolorizing composition according to this embodiment has the following configuration. (1) The decolorizing composition is used to decolorize textile media (textile media) that have been dyed with a dyeing material containing a sublimation dye such as a sublimation dye or a sublimation disperse dye. The decolorizing composition contains a chain-like compound as an active ingredient, which includes one hydroxyl group and multiple alkoxy or ether groups.

[0084] In dyed fiber media, the dye (dyeing material) is held in the gaps between the molecular chains of the fibers that make up the media. The fiber opening temperature refers to the temperature at which the molecular chains of the fibers that make up the media loosen enough (the gaps widen) to allow the dye held between the molecular chains of the fibers to escape, or the temperature at which the attractive forces between the fiber molecules weaken. A decolorizing composition containing at least one of ether bonds and ester bonds in its molecular structure has high affinity for dyeing materials. When the decolorizing composition in which media M is immersed is heated to at least the fiber-opening temperature, the dye held in the gaps between the molecular chains of the fibers is transferred from the media to the decolorizing composition, thereby decolorizing the media.

[0085] By using a decolorizing composition containing a chain compound with one hydroxyl group and multiple alkoxy or ether groups as an active ingredient, media M printed with sublimation dyes can be appropriately decolorized. In particular, it can effectively decolorize polyester media even if the colored areas include darker regions. This allows media printed with dyes to be decolorized and recycled.

[0086] (2) The decolorizing composition is used to decolorize textile media (textile media) that have been dyed with a dyeing material containing a sublimation dye such as a sublimation dye or a sublimation disperse dye. The decolorizing composition contains a chain-like compound comprising one hydroxyl group and multiple alkoxy or ether groups, and a surfactant as an active ingredient.

[0087] By using a decolorization composition containing a chain compound with one hydroxyl group and multiple alkoxy or ether groups, and a surfactant as an active ingredient, media M printed with sublimation dyes can be appropriately decolorized. In particular, even if the colored area includes dark-colored regions, fibrous media can be properly decolorized. Furthermore, the inclusion of a surfactant reduces the number and duration of decolorization treatments using the decolorization composition compared to cases without a surfactant. This allows for proper decolorization of fiber-based media composed of colored fibers. Furthermore, bleaching can cause shrinkage and other damage to the fibers due to the drying process after bleaching. By including a surfactant, the number of bleaching treatments can be reduced, thereby minimizing the degree to which the media shrinks during the bleaching process.

[0088] (3) In (2) above, The surfactant is at least one of the following: anionic surfactant or nonionic surfactant. An anionic surfactant is at least one of the following surfactants: sulfonic acid-based, phosphoric acid-based, lauric acid-based, or dodecylic acid-based. Nonionic surfactants are at least one of the following: surfactants that have a hydroxyl group that does not ionically dissociate in water as a hydrophilic group, and surfactants that have an ether bond as a hydrophilic group.

[0089] With this configuration, even if the colored area includes darker regions, the fibrous media can be properly decolorized.

[0090] (I) In (1) or (2) above, Textile media are polyester media dyed using dyeing materials containing sublimation dyes, such as sublimation dyes or disperse dyes with sublimation properties.

[0091] In dyed polyester media, the dye is held in the gaps between the polyester molecular chains that make up the media. At the fiber opening temperature, the polyester molecular chains that make up the media loosen (the gaps widen) to the extent that the dye held between the polyester molecular chains can escape. A decolorizing composition containing a chain-like compound with one hydroxyl group and multiple alkoxy or ether groups as an active ingredient has high affinity for the molecules of sublimable dyes mainly used in sublimation printing. When the decolorizing composition, in which media M is immersed, is heated to at least the fiber-opening temperature, the dye held in the gaps of the polyester molecular chains is transferred from the media to the decolorizing composition, thereby decolorizing the media.

[0092] (4) In (3) or (I) above, The surfactant is at least one selected from the following: Sodium diethylhexyl aerosol sulfosuccinate, polyoxyethylene (23) lauryl ether, polyoxyethylene (10) octylphenyl ether, sodium monododecyl phosphate, sodium laurate, sodium dodecyl sulfate, lauryltrimethylammonium chloride, sorbitan monopalmitate

[0093] b after one bleaching treatment * The value is lower when decolorization is performed using a decolorization composition containing a surfactant than when decolorization is performed using a decolorization composition without a surfactant. As a result, the decolorizing composition contains at least one selected from the above surfactants, which, compared to the case where it does not contain, results in a lower b after decolorization. * This reduces the number of decolorization cycles required for the value to fall below the threshold Th. This method allows for proper decolorization of media M while minimizing its shrinkage. This enables the decolorization of media printed with dyes for recycling. Because the media shrinks less during decolorization, an improvement in recycling yield can be expected.

[0094] (5) In any one of (1) to (4) or (I) above, The chain-like compound is at least one selected from the following: Sodium diethylhexyl aerosol sulfosuccinate, polyoxyethylene (23) lauryl ether, polyoxyethylene (10) octylphenyl ether, sodium monododecyl phosphate, sodium laurate, sodium dodecyl sulfate, lauryltrimethylammonium chloride, sorbitan monopalmitate

[0095] In polyester, ester bonds repeatedly appear along the longitudinal direction of the molecular chain. Linear compounds containing ester and ether bonds have a high affinity for polyester. Furthermore, dyes held in the gaps between the polyester molecular chains also have a high affinity for the decolorizing composition. Therefore, when the decolorizing composition into which the media is immersed is heated to at least the fiber-opening temperature, the dyes held in the gaps between the polyester molecular chains are transferred from the media to the decolorizing composition, thereby decolorizing the media.

[0096] By using at least one of the above-mentioned chain compounds as a compound that satisfies this requirement, polyester media can be properly decolorized even if the colored area includes dark-colored regions. This allows for proper decolorization of media M while minimizing shrinkage. This enables the decolorization of media printed with dyes for recycling. Because the media shrinks less during decolorization, an improvement in recycling yield can be expected.

[0097] (II) In any one of (1) to (5) or (I) above, Textile media include plain weave fabrics and twill weave fabrics.

[0098] With this configuration, when media M is heated to its opening temperature, the spacing between weaves widens. The decolorizing composition described above has a high affinity for the molecules of sublimable dyes mainly used in sublimation printing, and as the spacing between weaves widens, the opportunities for contact with the sublimable dye molecules incorporated into the interior of media M increase. This allows the dye incorporated between the molecular chains of the fibers within the media M to be transferred to the decolorizing composition, thereby enabling effective decolorization of the media M. Furthermore, because the media M is a woven fabric, excessive shrinkage of the media after drying by heating and pressurizing can be suppressed. This allows for the decolorization and proper reuse of plain weave or twill weave media, making it possible to decolorize and recycle polyester media on which information has been printed using dyes.

[0099] The present invention can also be specified as a method for decolorizing a fibrous media that has been dyed using a dyeing material containing a sublimable dye. Here, the textile media is dyed using a dyeing material that contains sublimation dyes, such as sublimation dyes or disperse dyes with sublimation properties. (6) Decolorization of fibrous media is carried out using a decolorization composition containing a chain compound having one hydroxyl group and multiple alkoxy or ether groups as an active ingredient. Decolorization of fibrous media (decolorization process) is performed by immersing the fibrous media in a decolorization composition and heating it at a temperature higher than the fiber opening temperature, or by immersing it in the decolorization composition that has been heated at a temperature higher than the fiber opening temperature.

[0100] This method allows the dye, which is held in the gaps between the molecular chains of the fibers constituting media M, to be transferred from media M to the decolorizing composition, thereby decolorizing media M.

[0101] (III) The decolorization method is The method includes a decolorization step in which a fibrous media M is immersed for a first predetermined time in a decolorization composition heated to a first predetermined temperature higher than the fiber-opening temperature at which the molecular chains of the fibers constituting the media loosen, thereby transferring the dye from the media M to the decolorization composition and decolorizing the media M.

[0102] A decolorizing composition containing a chain-like compound with one hydroxyl group and multiple alkoxy or ether groups as an active ingredient has high affinity for the molecules of sublimable dyes mainly used in sublimation printing. When the decolorizing composition in which media M is immersed is heated to a first predetermined temperature at least higher than the fiber opening temperature, the dye held in the gaps of the molecular chain is transferred from media M to the decolorizing composition, thereby decolorizing media M.

[0103] (IV) In (III) above, The chain compound contains at least one chain compound selected from the following: 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-isobutoxyethoxy)ethanol, 2-[2-(butoxyethoxy)ethoxy]ethanol, 2-[2-(methoxyethoxy)ethoxy]ethanol, 2-(2-hexyloxyethoxy)ethanol.

[0104] By including at least one of these compounds as an active ingredient, the media M can be appropriately decolorized while suppressing shrinkage. This allows media printed with dyes to be decolorized and recycled. Since there is less shrinkage of the media during decolorization, an improvement in the recycling yield can be expected.

[0105] (V) In (IV) above, Furthermore, it contains at least one surfactant selected from the following: Sodium diethylhexyl aerosol sulfosuccinate, polyoxyethylene (23) lauryl ether, polyoxyethylene (10) octylphenyl ether, sodium monododecyl phosphate, sodium laurate, sodium dodecyl sulfate, lauryltrimethylammonium chloride, sorbitan monopalmitate

[0106] b after one bleaching treatment * The value is lower when decolorization is performed using a decolorization composition containing a surfactant than when decolorization is performed using a decolorization composition without a surfactant. As a result, the decolorizing composition contains at least one selected from the above surfactants, which, compared to the case where it does not contain, results in a lower b after decolorization. * This reduces the number of decolorization cycles required for the value to fall below the threshold Th. This method allows for proper decolorization of media M while minimizing its shrinkage. This enables the decolorization of media printed with dyes for recycling. Because the media shrinks less during decolorization, an improvement in recycling yield can be expected.

[0107] The present invention can also be identified as a decolorization apparatus for decolorizing a fibrous media dyed with a dyeing material containing a sublimable dye. (6) The decolorization device 1 is A decolorizing composition S used for decolorizing a fibrous media M, and containers 2 and 2' for containing the fibrous media, The invention includes a heating device as a heating means for heating a decolorizing composition S to a temperature higher than the fiber opening temperature at which the molecular chains or intermolecular forces of the fibers constituting the media M loosen.

[0108] With this configuration, the dye held in the gaps between the molecular chains of the fibers can be transferred from the media to the decolorizing composition, thereby decolorizing the media. In particular, by using the decolorizing composition described in any one of (1) to (4) or (I) above, decolorization of fibrous media can be effectively performed.

[0109] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments shown. It can be modified as appropriate within the scope of the technical idea of ​​the invention. [Explanation of symbols]

[0110] A~C Decolorizing composition M Media V-shaped conveyor belt 1, 1' Decolorization device 2, 2' container 3 Heating device (heating means) 4, 4' Air drying device 4 (drying means)

Claims

1. A decolorizing composition used for decolorizing textile media dyed with a dyeing material containing a sublimation dye such as a sublimation dye or a sublimation disperse dye, A decolorizing composition comprising a chain-like compound containing one hydroxyl group and multiple alkoxy or ether groups as an active ingredient.

2. A decolorizing composition used for decolorizing textile media dyed with a dyeing material containing a sublimation dye such as a sublimation dye or a sublimation disperse dye, A chain-like compound containing one hydroxyl group and multiple alkoxy or ether groups, A decolorizing composition comprising a surfactant and as active ingredients.

3. In claim 2, The surfactant is at least one of an anionic surfactant and a nonionic surfactant. The anionic surfactant is at least one of the following: sulfonic acid-based, phosphoric acid-based, lauric acid-based, or dodecylic acid-based surfactants. A decolorizing composition comprising a nonionic surfactant, which is at least one of a surfactant having a hydroxyl group that does not ionically dissociate in water as a hydrophilic group, and a surfactant having an ether bond as a hydrophilic group.

4. In any one of claims 1 to 3, The decolorizing composition wherein the chain-like compound is at least one selected from the following: 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-isobutoxyethoxy)ethanol, 2-[2-(butoxyethoxy)ethoxy]ethanol, 2-[2-(methoxyethoxy)ethoxy]ethanol, 2-(2-hexyloxyethoxy)ethanol.

5. A method for decolorizing a textile media dyed with a dyeing material containing a sublimation dye, such as a sublimation dye or a sublimation disperse dye, The decolorizing composition used for decolorizing the aforementioned fibrous media is: It contains a chain-like compound as an active ingredient, which includes one hydroxyl group and multiple alkoxy or ether groups. A decolorization method comprising immersing the fibrous media in the decolorization composition and heating it at a temperature higher than the fiber opening temperature at which the molecular chains or intermolecular forces of the fibers loosen, or immersing it in the decolorization composition heated at a temperature higher than the fiber opening temperature.

6. An apparatus for decolorizing a textile media dyed with a dyeing material containing a sublimation dye, such as a sublimation dye or a sublimation disperse dye, A decolorizing composition used for decolorizing the aforementioned fibrous media, and a container for containing the aforementioned fibrous media, The method includes heating means for heating the decolorization composition to a temperature higher than the fiber opening temperature at which the molecular chains or intermolecular forces of the fibers are relaxed. A decolorizing apparatus comprising a decolorizing composition used for decolorizing the aforementioned fibrous media, the decolorizing apparatus containing a chain-like compound having one hydroxyl group and multiple alkoxy or ether groups as an active ingredient.

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