Jagson Colorchem Limited offers Cold Brand Reactive Dyes. Jagson Colorchem Limited is an ISO 9001:2000 accredited company. The Cold Brand Reactive Dyes, also known as Dycrofix `M` Dyes, have good reactivity and fastness. The Cold Brand Reactive Dyes require milder alkaline conditions for applications and fixation at the optimum temperature of 25-35 Deg. C.