Study On Dyeing Of Raw Silk With Reactive Dyes And Mechanism

Silk is composed of fibroin and sericin.The silk is famous as the "second skin" because of its soft luster,flexibility and moisture permeability.It is popular as a high-grade fabrics.Nowadays,the vast majority of the market are silk fabric,refined from the products of sericin.The style is single,usually used for making underwear,scarves and thin clothing.And the process of removing the sericin,not only wastes resources,but also pollutes the environment.The Beijing Olympic Games etiquette Miss wear the awards dress,which is woven by the Kegan yarn(raw silk)woven directly from the fabric,modeling aesthetic,fashionable and popular with the public.Therefore,the silk thread directly stained,while retaining the silk silk surface of the sericin,to ensure the quality of dyeing at the same time on the fabric style control,which has a very important theoretical and practical significance.In this paper,we studied the dyeing process and mechanism of raw silk with reactive dyes,and also improved the feel of silk fabrics after dyeing.The research is as follows:(1)Using reactive dyes with different active groups.The dyeing depth,color fastness and sericite dissolution rate were used as indexes to optimize the dyeing process;(2)The dyeing mechanism of raw silk reactive dyes was analyzed by means of dyeing rate curve,infrared spectroscopy and high performance liquid chromatography;(3)After dyeing,we use mechanical and chemical methods for finishing to meet the different requirements.Results show:(1)Selecting high reactive dyes can reduce the loss of sericin in the dyeing process.Four reactive dyes for raw silk dyeing,the preferred process is:FL-RN: fixing temperature 40 ℃,soda ash 2 g/L,sodium sulfate 50 g/L;color fastness above 4,rubbing fastness is 3-4.Ciba Clone Blue 4R: fixing temperature 40 ℃,soda ash 1 g/L,sodium sulfate 50g/L;color fastness above 4,rubbing fastness is 3-4.Ciba Clone Red FN-R: fixing temperature 60 ℃,soda ash 2 g/L,sodium sulfate 50g/L;color fastness above 4-5,rubbing fastness is 3-4.M-3RE: fixing temperature 65 ℃,soda ash 1 g/L,sodium sulfate 50 g/L;color fastness above 4,rubbing fastness is 3-4.(2)The rate of dyeing of reactive dyes on raw silk is higher than that of silk;Infrared spectroscopy show that amino and phenolic hydroxyl groups is the main groups with reactive dyes and also a very small number of alcohol hydroxyl involved in the reaction;Analyzed the content of tyrosine in the degumming solution by high performance liquid chromatography,sericin on the sericin reactsed with reactive dyes.(3)After dyeing,the silk fabric is stiff and it can be improved to varying degree after mechanical and chemical soft finishing methods.Using rolling mill rolling for mechanical soft finishing,after 50 rolling,the fabric stiffness decreased by 5-6 %;Using 5 g/L soft agent padding for chemical soft finishing,stiffness decreased by6-8 %;After 30 times rolling and 2.5 g/L softener treatment,stiffness decreased by6-7 %,the effect is good and side effects are small.