Investigation Of Photostability And Safety Of Four Plant Hair Colorants

In recent years,with the increase of people's health and environmental awareness,plant hair dyes have received extensive attention.This paper selected the red plant material sappanwood,the yellow plant material henna and the black plant material walnut,which have been studied in the field of wool dyeing.At the same time,selected the black plant raw gall nut which can be used for hair dyes in the safety and technical standards for cosmetics.This article mainly discusses the safety of four plant hair dyes by in vitro test and the light stability of pigments and hair after dyeing.The main work and results are as follows:Firstly,discussed the optimal extraction condition of four plant extracts and the content of main pigments in the extracts by high performance liquid chromatography.From the experimental results,it can be seen that the sappawood mixed with 80% ethanol at 1:25,then react for 160 min by reflux condensation at a temperature of 60? which can get the high content of Brazilian in the extract is up to 9.538%;the gallnut mixed with 80% ethanol at 1:75,then react for 100 min by reflux condensation at a temperature of 80?which can get the high content of tannin in the extract is up to 91.56%;the walnut mixed with 50% ethanol at 1:25,then react for 120 min by reflux condensation at a temperature of 60? which can get the high content of juglone in the extract is up to 0.0891%;the henna mixed with 0.25 M Na OH at 1:55,then react for 140 min by reflux condensation at a temperature of 90? which can get the high content of lawsone in the extract is up to 0.6952%.The four extracts were made into hair dyes,and then dye the yak hair.By optimizing the dyeing conditions and dyeing methods to enhance the dyeing effect.From the experimental results,it was found that the optimum amount of the extract in the sappanwood hair dye was 0.5% and adjust the p H to 7;The optimum amount of the extract in the gallnut hair dye was 2% and adjust the p H to 4;The optimum amount of the extract in the walnut hair dye was 4% and adjust the p H to 4;The optimum amount of the extract in the henna hair dye was 6.6% and adjust the p H to 10.All the mordants used 5.5% Fe2+ aqueous solution.The dyeing method of sappanwood and walnut hair dye was pre-mordanting,and the dyeing methods of gallnut and henna hair dyes were post-mordanting.The safety of the four extracts and the hair dyes by in vitro test.The 3T3 Neutral Red Uptake Cytotoxicity Assay results showed that the extract of sapanwood was medium toxicity,and the extract of gallnut was low toxicity,the extracts of henna and walnut were all microtoxicity.The results of the BCOP and HET-CAM experiments showed that the mordants were non-irritating,the softeners were medium irritating,and the sappanwood hair dyes,henna hair dyes,and walnut hair dye gallnut hair dyes were mild eye irritation.H3 D PT show that none of the four plant hait hyes have skin irritation.Finally,discussed the photostability of pigments and hairs after applying the four plant hair dyes to human hair.From the experimental results,it can be known that UVA can cause degradation of the pigments and cause discoloration,curling of the hair scales.At the same time,UVA will causes free radicals which can damage the hair.