Kaltbeize AL
Coldmordant AL

A mordant for Coloring textile fibres with natural colors

Like alum and aluminium sulfate, Kaltbeize AL supplies the alumina, which makes natural colors insoluble in water and permanently fixes them on protein fibres.
The standardprocedure to get alumina out of alum or aluminium sulfate is to cook
the textile fibers fore an our in a highly concentrated solution with an extremly high surplus of mordant supplying alumina.
Unfortunately, a high induction of energy is nessesary for alum or aluminium sulfates to separate from their acid during the standard procedure.

Moreover, the sulfuric acid that is set during the mordanting process, is extremly harmful to the environment.
Opposed to the standard procedere KALTBEIZE  AL
supplies the alumina without inducing any heat, but it needs a little more time. It will supply alum from the same mordanting bath, until the alumina is (almost) competely extracted. The remants consist of formic acid, which belongs to the non-poisonous organic acids and morever is ethereal. Formic acid and its salts can easily be reducted biologically, so they do not cause as many ecological problems.

Technical specification

Basis:  salt of alumina
Appearance: white powder
Content of alumina: 23-24 % AL203
Solubility: very slowly in cold water, the solution keeps a milky colour; easily soluble in warm water to a maximum of 158° F

Working with KALTBEIZE AL is particulary easy because
  • the quantity of mordant doesn`t need to be related to the dry fibre material
  • no fixed relation of bath ratio must be observed
  • mordanting temperature and dwelling time is not prescribed
  • there is no need of a heat-resistent mordanting vessel
  • after the mordanting procedure there isn`t any problem of disposing
Preparation of mordanting solution

With warm water at a temperature of at most 122° F, KALTBEIZE AL is to be brougt into a solution of 2 %, i.e.20 gr of KALTBEIZE AL are to be solved in 1 liter of water.

Examble: Preparation of a mordant bath of 10 ltr. (in a plastic bucket):

10 x 20 gr =  200 gr of KALTBEIZE AL  are to be weighed and poured into the bucket and then solved with 5 liter of warm water (122 ° F). Cold water is added until a quantity of 10 ltr. The mordant can be used immediately. The dwelling time in the mordanting bath should be 8 hours or more at room temperature, ca. 2 hours at 122° F. The dwelling time can be prolonged without restriction.

Working with the mordant and its productivity

Concerning the quantity of the alumina which is produced, KALTBEIZE AL is almost inexhaustible, but there is the problem that fluid gets lost when taking out the material which is mordanted. Therefore the material should be wrung out as strongly as possible, or even better should be centrifugated the extracted fluid should be poured back into the mordanting bath. During this procedure the bath can also be refilled with water to a maximum of 20%. When working carefully in this way, the mordanting bath can be re-used up to six times.

One more tip for fatty wool: Lanolin prevents the fibre  to absorb the color because it is mordanted  and colored itself, but doesn`t stick to the fibre. Therefore it is sensible to mordant defatted wool and, if needed, add fat again after the colouring.

Mordanting on supply

KALTBEIZE AL  has no damaging influece on textil fibres. Thus, material which has been mordanted can stay in the bath during weeks or month. Hence one always has a supply of newly mordanted material at one´s disposal.