Method for improving color depth and light fastness of natural dye-dyed fabric

[0018] Example 1

[0019] (1) Pour the pure cotton fabric into 4% polyvinylpyrrolidone (molecular weight 8000) solution with a mass fraction of solute, double dip and two rolls, with 100% remnant rate, dry at 80°C for 10 minutes, and cool down after drying. To room temperature, wash in hot water at 40°C for 15 minutes, then air dry naturally for later use;

[0020] (2) Use chestnut shell natural dyes to dye the textiles treated in step (1). The amount of natural dyes is 2% (owf), that is, 100 grams of textiles require 2g of natural dyes (here refers to 100 grams of non-step ( 1) The treated original textile requires 2g of natural dye, the same is true in the following examples), bath ratio 1:20 (here also refers to the ratio of the quality of the original textile without step (1) to the mass of the dye liquor, in the following examples The same is true), dyeing temperature is 50℃, dyeing time is 90min, after dyeing, the fabric is washed 3 times with water and air-dried naturally;

[0021] (3) The natural dye-dyed fabric treated in step (2) is immersed in zinc acetate dihydrate solution, the amount of zinc acetate is 5% (owf) (here refers to 100 grams of the original textile that has not been treated in step (1) , 5g zinc acetate is needed, the same is true in the following examples), bath ratio 1:20 (here also refers to the ratio of the quality of the original textile without step (1) to the mass of the dye liquor, the same is true in the following examples), immersion temperature 50°C, immersion time 90min, after immersion is finished, roll pressing, the residual rate is 80%;

[0022] (4) Immerse the zinc acetate textile treated in step (3) into diethylene glycol, and the mass volume ratio of textile to diethylene glycol is 1:50 in g:mL (here is It refers to the weight ratio of the original textile without treatment in step (1) to the volume ratio of alcohol, the same in the following examples), heat the oil bath to 180°C, and under stirring, quickly add 1mol/L NaOH/diethylene glycol Solution, the ratio of the amount of NaOH to the mass of the textile is 0.05:1 (here refers to: the ratio of the mass of NaOH to the weight of the original textile without step (1), the same is true in the following examples), after the addition, the temperature is raised Heat for 30 minutes at 200°C. After the heat preservation is over, cool to room temperature, take out the fabric, wash 3 times with absolute ethanol, and dry.

[0027] Example 2

[0028] (1) Padding the silk fabric in an aqueous solution of 8% polyvinylpyrrolidone (molecular weight of 55000) with a mass fraction of solute, two dipping and two rolling with a surplus rate of 80%, drying at 100°C for 5 minutes, and cooling to room temperature after drying ,Wash in hot water at 60℃ for 10min, then dry naturally for later use;

[0029] (2) Use mulberry natural dyes to dye the textiles treated in step (1). The amount of natural dyes is 4% (owf), that is, 100 grams of textiles require 4g natural dyes, bath ratio 1:50, dyeing temperature 100℃, Dyeing time is 30min. After dyeing, the fabric is washed 5 times with water and dried naturally;

[0030] (3) Immerse the natural dye-dyed fabric treated in step (2) in zinc acetate dihydrate solution, the amount of zinc acetate is 15% (owf), the bath ratio is 1:50, the immersion temperature is 70℃, the immersion time is 60min, and the immersion After the end, the rolls are rolled, and the rolling residual rate is 100%;

[0031] (4) Immerse the zinc acetate padding textile treated in step (3) into triethylene glycol, the mass volume ratio of textile to triethylene glycol is 1:150 in g:mL, oil bath Heat to 180℃, quickly add 1mol/L NaOH/triethylene glycol solution with stirring, the ratio of NaOH to textile mass is 0.25:1, after the addition, heat up to 200℃, keep for 45min, after the end , Lower to room temperature, take out the fabric, wash 5 times with absolute ethanol, and dry.

[0036] Example 3

[0037] (1) Pour the wool fabric into a 6% polyvinylpyrrolidone (molecular weight: 30000) solution with a mass fraction of solute, two dips and two rolls, with a surplus rate of 90%, and dry at 90°C for 7 minutes. After drying, cool to room temperature ,Wash in hot water at 50℃ for 12min, then dry naturally for later use;

[0038] (2) Use gardenia yellow natural dye to dye the textile treated in step (1), the amount of natural dye is 3% (owf), that is, 100 grams of textile requires 3g natural dye, liquor ratio 1:40, dyeing temperature 80 ℃, dyeing time is 45min, after dyeing, the fabric is washed 4 times with water and dried naturally;

[0039] (3) Immerse the natural dye-dyed fabric treated in step (2) in a zinc acetate dihydrate solution, the amount of zinc acetate is 10% (owf), the bath ratio is 1:40, the immersion temperature is 60℃, the immersion time is 70min, and the immersion After the end, the rolls are rolled, and the rolling residual rate is 90%;

[0040] (4) Dip the zinc acetate textile treated in step (3) into glycerin. The mass-volume ratio of textile to glycerin is 1:100 in g:mL. Heat the oil bath to 180°C, and quickly add under stirring 1mol/L NaOH/glycerin solution, the ratio of NaOH to the textile is 0.10:1. After the addition, the temperature is raised to 200℃, and the temperature is kept for 40 minutes. After the heat preservation is over, it is cooled to room temperature. The fabric is taken out and washed with absolute ethanol for 4 times. , Let dry.