Purchase safer solvents or implement safer processes

The ZDHC MRSL bans the intentional use of certain solvents. Suppliers should make all efforts to substitute these with safer solvents. Suppliers should also consider changing production processes in order to eliminate the use of ZDHC MRSL restricted solvents.

Finding safer solvent alternatives

Certain solvents are banned from intentional use in the ZDHC MRSL V3.1. Suppliers should make all efforts to substitute these with safer solvents or safer (water-based) processes.

The table below suggests safer processes that facilities can adopt. Suppliers should make their own informed substitution decisions.

DMFa

Function: Synthetic coated fabric

Alternative process: water-based solvent-free

Tetracholoethylene

Function: Dry cleaning

Alternative process: Carbon dioxide cleaning (liquid or supercritical) wet cleaning with aqueous detergents and conditioners.

Various

Function: Surface cleaning

Alternative process: Aqueous vacuum degreasing, aqueous vacuum cycling nucleation, ultrasonic cleaning, spray cleaning, pressure washing, immersion.

Hot Melt Adhesives

Hot Melt Adhesives (HMAs) are safer alternatives for solvent-based adhesives used in bonding shoe soles and shoe uppers. They are made of thermoplastic elastomers such as ethylene-vinyl acetate (EVA), amorphous poly alpha olefin (APAO), ethylene-methyl acrylate, ethylene n-butyl acrylate, styrene block copolymers and polyamides (PA).

Some tackifiers such as hydrogenated rosin, rosin esters and terpene derivatives, are also incorporated in the HMA.

Hot melt glue has low VOC emissions, quick curing and wide surface bonding properties. It is suitable for continuous production and convenient for storage and transportation.

In developed countries, hot melt glue (including hot melt pressure sensitive glue) has accounted for more than 20% of the total synthetic adhesive.

Hot melt can also be applied in several ways, including through nozzles, extrusion, melt blowing, spiral spraying, screen printing and slot die coating. It can be disposed of without any special precautions.

Candidate alternative

Textile washing and cleaning : Tetracholoethylene

Cyclohexane & propan-2-o
Soalkanes C11-15 & 3,5,7-trimethyldecane

Cleaning (textile connection unclear) : NMP/NEP and tetracholoethylene

Methyl 408 and ethyl 408

PAI, PI nylon and PUR synthesis : DMFa/DMAC and NMP/NEP

KJCMPA-100

Polyurethane synthetic coated fabric: DMFa/DMAC

Dihydrolevoglucosenone (Cyrene^TM)
Dimethylisosorbide
Gamma-valerolactone
Cyclopentyl methyl ether (cPME)
Glycofurol (THFP)
Propylene carbonate
Dimethyl glutarate

Dry cleaning: Tetracholoethylene

High flash point hydrocarbons (DF-2000^TM Ecosolv)

Polymer dissolution: DMFa/DMAC and NMP/NEP

Solketal
Dimethyl sulfoxide (DMSO)

Footwear

In footwear manufacturing processes, the following safer solvents listed in U.S. EPA’s Safer Chemical Ingredients List can be used, since they meet the Safer Choice Criteria for solvents. (Suppliers should conduct trials to determine if they will be appropriate for every manufacturing situation):

1,1'-Oxidipropan- 2-0l; Cas no. 110-98-5
Hexane-1,2 diol Cas no. 6920-22-5
Butane-1,3-doil Cas no. 107-88-0
Propane-1,3-doil Cas no. 504-63-2
Hexane-1,6-diol Cas no. 629-11-8
2,2-dimethyl-1,3-dioxolane-4-methanol Cas no. 100-79-8
3- methoxy-3-methylbutane-1-ol Cas no. 56539-66-3
Caprylyl glycol Cas no. 1117-86-8
(Z)-octadec-9-enol Cas no. 143-28-2
Oxydipropanol Cas no. 25265-71-8
Tripropylene glycol Cas no. 24800-44-0
Tetraethylene glycol Cas no. 112-60-7
1-propoxypropan-2-ol Cas no. 1569-01-3
2 methylpentane-2,4-diol Cas no. 107-41-5
Glycerol triacetate Cas no. 102-76-1
Isopropyl myristate Cas no. 110-27-0
Butyl stearate Cas no. 123-95-5
Ethyl 3-ethoxypropionate Cas no. 763-69-9
Propylene carbonate Cas no. 9 108-32-7
Dimethyl glutarate Cas no. 1119-40-0
Dimethyl adipate Cas no. 627-93-0
Dimethyl succinate Cas no. 106-65-0
Ethyl lactate Cas no. 97-64-3
Dimethyl methylglutarate Cas no. 14035-94-0
Tripropylene glycol n butyl ether Cas no. 55934-93-5
Propylene carbonate Cas no. 108-32-7
Castor oil Cas no. 8001-79-4
Glycerol Cas no. 56-81-5
White mineral oil, petroleum (residual content of benzene in the complex oil-derived substances should be below 0.1%) Cas no. 8042-47-5
Polyethylene glycol monomethyl ether Cas no. 9004-74-4
Ethyl acetate Cas no. 1 141-78-6