Every beaker dyeing machine does the same job: rotate sealed beakers at a controlled temperature so that a small sample dyes the way a bulk batch would. What separates them is how the heat gets in — and that decides temperature uniformity, cycle time, cleanliness and price.
Infrared
Beakers rotate inside a chamber heated by infrared emitters. No heat-transfer medium at all.
Strengths: fastest heat-up of the three; nothing to top up, drain or clean; no fumes; the machine stays clean indefinitely. Reaches HTHP temperatures for disperse dyeing on polyester.
Trade-offs: highest capital cost. Uniformity depends on emitter condition and beaker placement, so emitters are a maintenance item.
Buy it if you run many short cycles a day and lab throughput is your constraint. See the Infra Colour Dyeing Machine.
Glycerin bath
Beakers rotate immersed in a heated glycerin bath. Glycerin holds temperature exceptionally evenly and reaches well above the boiling point of water without pressurising the bath itself.
Strengths: the best temperature uniformity of the three. Every beaker sees the same curve, which is exactly what you want when reproducing a bulk HTHP polyester recipe.
Trade-offs: glycerin needs topping up and eventually replacing; beakers come out needing cleaning; the bath is slower to heat and slower to cool.
Buy it if shade reproducibility on polyester matters more than cycle time — export dyehouses working to tight tolerance usually land here. See the Glycerin Bath HTHP Beaker Dyeing Machine.
Rota Dyer
Sealed beakers on a rotor inside a heated bath — the classic workhorse arrangement.
Strengths: lowest cost of the three; simple, robust, and easy for an operator to learn. Every sample gets an identical thermal and mechanical history.
Trade-offs: less headroom at the top of the temperature range than a dedicated HTHP glycerin machine.
Buy it if your work is mainly cotton, viscose, wool and blends, and polyester is occasional. See the Rota Dyer.
What about a shaker bath?
A shaker bath is not a rotary machine. Flasks sit in a reciprocating carrier in a temperature-controlled water bath, at atmospheric pressure. It costs considerably less than any of the three above and is the right answer for atmospheric dyeing, pre-treatment trials, wash-off and soaping — it just cannot do HTHP. Many labs run a shaker bath alongside a rotary machine rather than instead of one.
The machines that finish the job
Beaker dyeing gives you the shade. Getting from shade to a process a plant can run needs two more:
- Padding mangle — for pad-dry-cure and pad-batch trials, and for applying resin, softener and functional finishes at a controlled, repeatable wet pick-up. Pneumatic nip loading is what makes the pick-up repeatable; a spring-loaded padder is not comparable.
- HTHP steamer — fixation of printed and pad-applied dyes. With a super heater, one vessel covers saturated steam for reactive and acid prints and superheated steam for disperse.
For open-width work on crease-sensitive or heavy constructions, a laboratory jigger reproduces bulk jigger behaviour in a way no beaker machine can.
The part that is not the machine
A lab dyeing machine only pays for itself if the shade assessment behind it is controlled. Every recipe you approve is approved by eye, under whatever light is over the bench. Put a colour matching cabinet next to the dyeing machine and judge under D65, TL84 and the store lighting your customer sells under — that is how you catch a metameric match before it ships rather than after.
All of these are built to order in India, with installation and operator training. See the full Lab Testing Machines range, or tell us what you dye and we will recommend the combination.