A leuco dye pastel marking device for use with a substrate treated with an activator of the leuco dye, such that drawing upon the substrate will reveal a color, but drawing on a normal surface will have no visible effect. A solvent such as dimethyl adipate is used to store the leuco dye in a longer-lived, more stable, solid form, and varying hardnesses and consistencies may be achieved by the addition of 12 hydroxystearic acid and ethyl cellulose. The substrate may be treated selectively with the activator such that a texture, image, or hidden message is revealed by the application of the leuco dye pastel to the substrate. One or more substrates and one or more leuco dye pastel marking devices may be presented to a child as a coloring book with pastels that only visibly mark the coloring book and no other surface.

The present invention relates to a process for the production of a dyed biopolymer comprising the steps of providing at least one biopolymer-producing microorganism, providing at least one dye-producing microorganism, culturing said at least one biopolymer-producing microorganism to produce at least a biopolymer, and culturing said dye-producing microorganism wherein said dye-producing microorganism produce at least a dye suitable to dye at least part of said biopolymer, whereby a dyed biopolymer is obtained. The present invention also relates to a dyed biopolymer, to process for the production of a dyed composite article comprising at least the dyed biopolymer and to articles comprising the dyed biopolymer.

The present invention relates to a process wherein one or more dye precursors, e.g., indole, are provided to a textile and converted by one or more enzymes, e.g., an oxidizing enzyme, to provide the textile with a dye, e.g. indigo. At least the oxidizing enzyme is a hybrid enzyme including a binding domain that is suitable to bind the enzyme to the textile and/or increase the affinity of the enzyme for the textile, in particular, a cellulose binding domain (CBD).

The present invention relates to a process wherein one or more dye precursors, e.g., indole, are provided to a textile and converted by one or more enzymes, e.g., an oxidizing enzyme, to provide the textile with a dye, e.g. indigo. At least the oxidizing enzyme is a hybrid enzyme including a binding domain that is suitable to bind the enzyme to the textile and/or increase the affinity of the enzyme for the textile, in particular, a cellulose binding domain (CBD).

The present invention relates to a process wherein one or more dye precursors, e.g., indole, are provided to a textile and converted by one or more enzymes, e.g., an oxidizing enzyme, to provide the textile with a dye, e.g. indigo. At least the oxidizing enzyme is a hybrid enzyme including a binding domain that is suitable to bind the enzyme to the textile and/or increase the affinity of the enzyme for the textile, in particular, a cellulose binding domain (CBD).