Method for bleaching plush wool fibers in acidic state

Abstract

The invention relates to the technical field of plush processing, and discloses a method for bleaching plush wool fibers in an acidic state, which comprises the following steps: S1, adjusting equipment frequency conversion to 70%, 35 HZ; s2, pre-treatment is conducted, specifically, a plush cleaning agent is 1.2%, the temperature is 60 DEG C * 20 min, and overflow flushing is conducted to be clean; s3, after pretreatment is completed, soft water is added into the dye vat, an oxygen bleaching stabilizer and hydrogen peroxide are evenly diluted through material vat return liquid, the dye vat is added, the temperature is increased to 75 DEG C, heat preservation is conducted for 60 minutes, after heat preservation is completed, soft water is used for overflowing and cooling to 40 DEG C, and deoxygenase is added into the return liquid; s4, uniformly diluting sodium hydrosulfite and acetic acid with return liquid of the material vat, adding the diluted sodium hydrosulfite and acetic acid into the dye vat, operating for three minutes to detect that the pH value is 6, heating to 50 DEG C at the rate of 3 DEG C / min, and keeping the temperature for 40 minutes; and S5, checking the whiteness and hand feeling of the raw materials, and discharging the qualified raw materials. The used oxygen bleaching stabilizer is acidic, the pH value is 6 when the use amount is 5%, the dye liquor is weakly acidic and is close to the isoelectric point of plush fibers, the reaction of hydrogen peroxide can be stabilized, the fiber damage is effectively reduced, and the quality stability is improved.

Description

Technical Field

[0001] The invention relates to the technical field of plush processing, in particular to a method for bleaching plush wool fibers in an acidic state. Background Art

[0002] Plush is a thin layer of fine wool that grows on the outer epidermis of goats and hides at the root of their coarse hair. Its characteristics are: soft and smooth, strong hygroscopicity, good warmth retention, natural and soft fiber luster, and comfortable to wear after being made into ready-made clothes. It is the best fiber among textile raw materials so far, and is known as "soft gold" and "fiber diamond". Wool fiber and plush have similar physical properties. In order to achieve the whiteness and brightness of the color, the plush fiber should be bleached or dyed after bleaching. The principle is to destroy the chromophore groups in the fiber and remove the pigment through the oxidation of the oxidant to achieve the purpose of increasing whiteness and brightness. Because the fiber is fine and expensive, preventing fiber damage during the production process is the top priority. If you are not careful, it will cause irreparable quality problems and economic losses such as the fiber feeling astringent, the finished product feeling not fluffy enough, the warmth retention, moisture absorption and perspiration wicking performance decreased, and the loss of the characteristic characteristics of plush wool fabric.

[0003] Plush and wool are both animal protein fibers, and their isoelectric points are between pH 4.5 and 5. When bleaching or dyeing, the closer the bath is to its isoelectric point, the more stable its structure is and the less susceptible it is to damage. Its dyeing characteristics are acid resistance but not alkali resistance, because alkali can easily decompose the disulfide group in the cystine of plush, causing damage to the plush quality, and oxidants can also damage plush fibers. For a long time, the commonly used plush bleaching method in the industry is the double bleaching process of oxygen bleaching and reduction bleaching. Neutral oxygen bleaching stabilizer is added during oxygen bleaching.

[0004] The traditional oxygen bleaching stabilizer is alkaline, with a pH value of 9 at a normal dosage of 3%, which can cause certain damage to the plush fiber. In addition, the oxidation reaction of hydrogen peroxide in an alkaline environment is extremely unstable, which can easily aggravate fiber damage and cause quality problems such as uneven whiteness and batch differences. Therefore, seeking a suitable oxygen bleaching stabilizer that takes into account the whiteness of plush after bleaching and minimizes fiber damage has become a major problem that the industry has always faced and is difficult to overcome. Summary of the invention

[0005] The purpose of the present invention is to provide a method for bleaching plush wool fibers in an acidic state. The oxygen bleaching stabilizer used is acidic, and the pH value is 6 when the dosage is 5%. The dyeing solution is weakly acidic, close to the isoelectric point of the plush fiber, which can stabilize the reaction of hydrogen peroxide, effectively reduce fiber damage, and increase quality stability.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for bleaching plush wool fibers in an acidic state, comprising the following steps:

[0007] S1. Adjust the frequency of the equipment to 70%, 35HZ, to prevent the plush materials from sticking together and damaging the fibers;

[0008] S2, pre-treatment: 1.2% of plush cleaning agent, 60℃*20min, overflow rinse;

[0009] S3. After pretreatment, add soft water to the dye vat, the soft water temperature is 40℃, dilute the oxygen bleaching stabilizer evenly with the return liquid, and add it to the dye vat; dilute the hydrogen peroxide evenly with the return liquid of the material vat, add it to the dye vat, heat it to 75℃, the rate is 2℃ / min, keep it warm for 60 minutes, after the end of the insulation, use soft water overflow to cool it to 40℃, add deoxygenase to the return liquid, run it for 20 minutes, rinse it clean, the soft water temperature is 40℃;

[0010] S4, dilute the insurance powder evenly with the return liquid of the material tank, add it to the dye tank, dilute the acetic acid evenly with the return liquid of the material tank, add it to the dye tank, run for three minutes to test the PH = 6, heat up to 50 ° C, speed 3 ° C / min, keep warm for 40 minutes, and rinse with soft water overflow after the end of the insulation;

[0011] S5. Check the whiteness and feel of the raw materials, and ship them out of the machine only if they meet the requirements.

[0012] Preferably, the equipment in S1 is a loose fiber dip dyeing machine.

[0013] Preferably, the plush raw materials in S1 are beech plush from the same batch and with the same length.

[0014] Preferably, impurities such as grease in the raw materials are pre-treated in S2.

[0015] Preferably, the water level of the dye vat in S3 is set to 85%, and the amount of hydrogen peroxide used is 40 g / L.

[0016] Preferably, the amount of sodium hydrosulfite in S4 is 3%, and the amount of acetic acid is 1.5%.

[0017] Preferably, the temperature of the soft water in S4 is 40°C.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The method for bleaching plush fibers in an acidic state. The oxygen bleaching stabilizer used in the present invention is acidic, and the pH value is 6 when the dosage is 5%. The dyeing solution is weakly acidic, close to the isoelectric point of the plush fibers, which can stabilize the reaction of hydrogen peroxide, effectively reduce fiber damage, and increase quality stability.

[0020] 2. The method of bleaching plush fiber in acidic state uses new auxiliaries to make the pH of dye solution weakly acidic, improve the insulation temperature, fully oxidize the reaction, remove the use of softener in the last link of post-treatment, reduce the content of various auxiliaries in dyeing water, minimize the impact on the environment, reduce fiber damage, maximize the spinnability of plush fiber, significantly improve the yarn production rate, yarn strength and weaving performance, and meet the requirements of high yield, low consumption, energy saving, environmental protection and other aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the process of the present invention;

[0022] Figure 2 It is a schematic diagram of the results of the whiteness test and fiber length arrangement test of the bleached plush of the present invention;

[0023] Figure 3 This is a comparison chart of indicators before and after adjustment of the bleaching process of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See also Figure 1-Figure 3 The present invention provides a technical solution: a method for bleaching plush fibers in an acidic state, a pioneer production implementation plan:

[0026] S1. Select the same batch and same length of plush as input raw materials;

[0027] S2. Use neutral detergent for pre-treatment to clean the grease and other substances in the plush raw materials;

[0028] S3, replace the original oxygen bleaching stabilizer with the current oxygen bleaching stabilizer;

[0029] S4, the post-treatment is changed to overflow flushing to clean up the residual liquid after bleaching to ensure that the color and feel are qualified after production;

[0030] S5. The equipment is a loose fiber dip dyeing machine.

[0031] The specific steps are:

[0032] S1. Adjust the frequency of the equipment to 70% (35HZ) to prevent the plush materials from sticking together and damaging the fibers.

[0033] S2. Pretreatment: 1.2% wool cleaning agent, 60℃*20min. Rinse with overflow.

[0034] S3. After pretreatment, add soft water to the dye vat (soft water temperature 40℃, dye vat water level 85%), dilute the oxygen bleaching stabilizer evenly with the return liquid, and add it to the dye vat; dilute the hydrogen peroxide (40g / liter) evenly with the return liquid of the material vat, and add it to the dye vat. Raise the temperature to 75℃ (rate 2℃ / min), keep warm for 60 minutes, and after the end of the insulation, use soft water overflow to cool down to 40℃ (soft water temperature), add deoxygenase to the return liquid, run for 20 minutes, and rinse clean (soft water temperature 40℃).

[0035] S4. Use the return liquid of the material tank to dilute the insurance powder (3%) evenly, add it to the dye tank, use the return liquid of the material tank to dilute the acetic acid (1.5%) evenly, add it to the dye tank, run for three minutes and test the pH = 6. Raise the temperature to 50℃ (rate 3℃ / min), keep warm for 40 minutes, and rinse with soft water overflow after the end of the warming (soft water temperature 40℃).

[0036] S5. Check the whiteness and feel of the raw materials, and ship them out of the machine only if they meet the requirements.

[0037] The test steps for using the current oxygen bleaching stabilizer are as follows:

[0038] Prepare 80 ml of an aqueous solution with a hydrogen peroxide dosage of 40 g / L and original oxygen bleaching stabilizer and current oxygen bleaching stabilizer concentrations of 1%, 2%, 3%, 4% and 5% respectively, to simulate the dyeing liquid in the dye vat, test the pH values ​​with a pH meter and make records, then put 10 original wool pieces of 4 g each into the beaker of the prepared aqueous solution, then put the ten test samples into a shaking water bath and keep them warm at 60°C for 1 hour, then take them out, rinse, dehydrate, mark them and put them into a drying oven for drying. After drying, perform whiteness test and fiber length layout test respectively. The test results are as follows Figure 2 .

[0039] from Figure 2 The test data shows that when the whiteness of the plush after bleaching is the same, the original process uses more hydrogen peroxide and stabilizer than the current process, but the pH of the bleaching solution is weakly acidic, close to the isoelectric point of the plush, the hydrogen peroxide reaction is relatively stable, and the fiber damage is small, which greatly improves the fiber damage problem of the plush after bleaching and makes it feel more fluffy and soft, improves its spinnability and production rate, and plays a key role in improving the style of the finished product, and restores the light, soft, glutinous and warm style of the plush to a great extent. The neutral pH value is relatively mild, less irritating to the skin, and makes it more comfortable to wear. Therefore, the use of new additives has obvious advantages in terms of raw material utilization, cost savings, and improvement of product quality and competitiveness. It can be inferred that production is feasible, and pioneer samples can be arranged and further tested.

[0040] Compared with the original execution process (for specific data, see Figure 3 ):

[0041] The original bleaching process needs to add 2.5%-3% of the original oxygen bleaching stabilizer (fluffy plush, large bath ratio), when 3% is added, the pH value of the dye liquor can reach 9, which will damage the plush fiber to a certain extent. The normal wool bleaching temperature is 60℃. In order to reduce the damage to the plush fiber, the bleaching temperature of the plush was reduced to 50℃, and the amount of hydrogen peroxide used was increased by 40%. Although many measures have been taken to prevent the damage to the plush fiber and improve the whiteness of the plush, the plush feels astringent after bleaching. Adding 3% softener has a general effect. Compared with the original plush, the feel is quite different, and the fiber is damaged and the length loss is large.

[0042] The pH value of the current bleaching process dye solution is about 6, which is weakly acidic. The fibers of the plush are protected in this dye solution, so that the fiber state, length and other indicators are maintained in the best state.

[0043] If the bleached wool needs to be dyed with brighter colors later, the secondary dyeing will further damage the wool fibers and increase the short-pile rate. The addition of too many auxiliaries will affect the health of spinning and wool, causing pollution of rollers during the production process, a decrease in the production rate, and pilling after clothing making. It may even make the finished product not bright enough, leading to customer returns and causing great economic losses.

[0044] The use of new auxiliaries makes the pH of the dye liquor weakly acidic, increases the insulation temperature, fully oxidizes, removes the use of softeners in the final stage of post-processing, reduces the content of various auxiliaries in the dyeing water, minimizes the impact on the environment, reduces fiber damage, and optimizes the spinnability of plush fibers to the maximum, significantly improves the yarn production rate, yarn strength and weaving performance. At the same time, it meets the requirements of high yield, low consumption, energy saving, environmental protection and other aspects.

[0045] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for bleaching plush wool fibers in an acidic state, characterized in that: The following steps are involved: S1. Adjust the frequency of the equipment to 70%, 35HZ, to prevent the plush materials from sticking together and damaging the fibers; S2, pre-treatment: 1.2% of plush cleaning agent, 60℃*20min, overflow rinse; S3. After pretreatment, add soft water to the dye vat, the soft water temperature is 40℃, dilute the oxygen bleaching stabilizer evenly with the return liquid, and add it to the dye vat; dilute the hydrogen peroxide evenly with the return liquid of the material vat, add it to the dye vat, heat it to 75℃, the rate is 2℃ / min, keep it warm for 60 minutes, after the end of the insulation, use soft water overflow to cool it to 40℃, add deoxygenase to the return liquid, run it for 20 minutes, rinse it clean, the soft water temperature is 40℃; S4, dilute the insurance powder evenly with the return liquid of the material tank, add it to the dye tank, dilute the acetic acid evenly with the return liquid of the material tank, add it to the dye tank, run for three minutes to test the PH = 6, heat up to 50 ° C, speed 3 ° C / min, keep warm for 40 minutes, and rinse with soft water overflow after the end of the insulation; S5. Check the whiteness and feel of the raw materials, and ship them out of the machine only if they meet the requirements.

2. The method for bleaching plush wool fibers in an acidic state according to claim 1, characterized in that: The equipment in S1 is a loose fiber exhaust dyeing machine.

3. The method for bleaching plush wool fibers in an acidic state according to claim 1, characterized in that: The plush raw materials in S1 are beech plush from the same batch and with the same length.

4. The method for bleaching plush wool fibers in an acidic state according to claim 1, characterized in that: In the S2, impurities such as grease in the raw materials are removed by pre-treatment.

5. The method for bleaching plush wool fibers in an acidic state according to claim 1, characterized in that: The water level of the dye vat in S3 is set to 85%, and the amount of hydrogen peroxide used is 40g / L.

6. The method for bleaching plush wool fibers in an acidic state according to claim 1, characterized in that: The amount of hydrosulfite in S4 is 3%, and the amount of acetic acid is 1.5%.

7. The method for bleaching plush wool fibers in an acidic state according to claim 1, characterized in that: The temperature of the soft water in S4 is 40°C.

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