Bamboo dyeing process-Environment friendly direct dye
30 July 04

1. Environment-friendly direct dye

Direct dyes account for the majority of banned dyes. Therefore, in recent years, the development of environmentally friendly direct dyes has become the focus of new dyestuff development. Specific direct dye varieties are the following:

(1) Diaminostilbene disulfonic acid direct dyes: These dyes are of bright color, moderate fastness, and direct fastness Orange GGL (C.I. Direct Orange 39) is an environmentally friendly dye with good performance. Direct Fast Yellow 3BLL (C.I. Direct Yellow 106) is a triazole direct dye with a light fastness of 6-7. Direct Fast Green IRC (C.I. Direct Green 34) has high dye uptake, excellent color fastness, fastness to sunlight of 6 to 7, and wash fastness of 3 to 4 grades.

(2) 4.4′-diaminodiphenyl urea direct dyes: These dyes are non-carcinogenic and have high light fastness. The application of more varieties is an environmentally friendly dye. Such as direct fast yellow RSC (C.I. direct yellow 50), direct fast red F3B (C.I. direct red 80), C.I. direct brown 112, C.I. direct brown 126, C.I. direct brown 152 and so on.

(3) 4.4 `-diamino benzoic acid aniline direct dyes: These dyes have good fastness and are environmentally friendly dyes. Such as direct green N-B (C.I. direct green 89), direct yellow brown N-D3G (C.I. direct brown 223), direct black N-BN (C.I. direct black 166) and so on.

(4)4.4′-Diaminobenzenesulfonanilides Direct dyes: These dyes synthesize black direct dyes using diamino compounds, which have good dyeing properties and fastnesses. It is widely used in the dyeing of cotton, hemp, viscose, silk and leather. Developed and screened products that can replace direct dyes, such as C.I. Direct Black 166 (Direct Black N-BN), C.I. Acid Black 210 (Acid Black NT), C.I. Acid Black 234, etc.

(5) Diaminoheterocyclic direct dyes: These dyes are direct dyes synthesized from diaminoheterocyclic compounds, such as dibenzodioxazine direct dyes. These dyes have bright color, high color strength and fastness. , Fastness to sunlight is up to 7 levels. Representative varieties are C.I. Direct Blue 106 (Direct Fast Blue FF2GL), C.I. Direct Blue 10 8 (Direct Fast Blue FFRL) and so on.

(6) Eco-friendly direct dyes for polyester/cotton (poly/viscose) fabrics: Polyester/cotton, polyester/viscose blended fabrics and other fibers with different properties are dyed in the same bath, which requires direct dyes with excellent high temperature stability and good The promotion and replayability, good fastness and environmental performance. The directly blended D-type dyestuff developed by Shanghai Dyestuffs Co., Ltd. is an environmentally-friendly dye that can achieve the above-mentioned properties. Currently, there are more than 25 varieties, such as CI Direct Yellow 86 (Directly Blended Yellow DR), CI Direct Yellow 106 (Directly Blended Yellow D -3RLL ), CI224 direct-blended Dahong D-GLN, CI Direct Violet 66 (direct blend purple D-5BL), CI Direct Blue 70 (direct blend blue D-RGL), CI95 direct blend brown D-RS, CI direct Black 166 (direct blend black D-ANBA) and so on. Wherein the individual species are copper complexes, free copper should be within the limits specified by ETAD (250 mg/kg).

(7) Kayaeelon C-type dyes developed and screened by Nippon Kayaku Co., Ltd.: There are CI Direct Yellow 161 (Yellow C-3RL), CI Direct Red 83 (Rubine C-BL), CI Direct Blue 288 (Blue C-BK), CI Direct Green 59 (Caeen C-CK), CI Direct Black 117 (Crey C-RL), etc.

Thai Hyundai Group introduced the Modern Direct series of high-grade direct dyes, Dystar Corporation developed Sirius Plus series of direct dyes, Ciba introduced Cibafix ECO direct dyes, BASF introduced Diazo l series of direct dyes, and Yorkshire introduced Benganil series of direct dyes. These dyes have similar functions, such as bright color, high light fastness, environmentally friendly dyes free from heavy metals, and excellent high temperature stability, and are suitable for one-step dyeing of polyester/cotton blended fabrics.