Abstract: The present invention relates to a method and an apparatus for producing the raw material (46) used in producing black dye pigment. The invention further relates to a raw material (46) for producing black dye pigment as well as to the use of ash (20,24,26) separated from the raw synthetic gas (12, 14, 18) in the purification of the raw synthetic gas (12, 14, 18) generated in the gasification of a biomass (2, 4, 6) for producing black dye pigment.

Abstract: A method for recording a volume transmission hologram having angularly multiplexed diffraction fringe patterns that can cooperate to display polychromatic images and can be recorded with a single wavelength exposure source.

Abstract: A method of manufacturing a multilayer fibrous product. The product comprises at least two overlapping layers, each of which has a different fiber composition, and in the production of the product, chemical short stock is used at least partly. In the method, short stock is brought to a screening stage where fines, which pass a screen having an average hole size of 0.2-1.5 mm, are separated from it, in order to prepare at least two fiber fractions having different fiber compositions, and the fractions generated are recovered and included in different layers of the same fibrous product. With the invention, it is possible to screen an initial material and form a product which has better properties than a corresponding product, the initial material pulp of which has only been refined.