Abstract: Containers that are soluble in liquid methylmethacrylate and contain the PMMA powder fraction of a two-component system made up of PMMA powder component and liquid MMA monomer component are useful as components of packaging of powder/liquid two-component material, such as dental material, investment material for histology or metallography or in veterinary medicine.

Abstract: Lignin-containing fibrous materials, in particular paper and card, are treated with whiteness stabilizers for the purpose of reducing light-induced yellowing. The whiteness stabilizer are (i) thiols with at least one additional hydrophilic group from the series consisting of OH, NH2, NHR1m NR1R2, COOH, SO3H and PO3H2 and an amino acid/peptide structure (ii) thiols with a CC double bond (iii) or heteroaromatic thiols and (iv), heteroaromatic disulfides or polysulfides. HALS light stabilizers and/or UV stabilizers are advantageously additionally employed. The stability is increased further by a TiO2-containing coat on the fibrous material. Stabilzer compositions and fibrous material stabilized according to the invention, containing a whiteness stabilizer of group (i) to (iv) are also disclosed.