Abstract: A transfer printing medium comprising a substrate supporting a thermal transfer dye and a radiation absorber positioned to provide thermal energy to the transfer dye when subjected to radiation within a predetermined absorption waveband, has a radiation absorber which is an infra-red absorbing poly(substituted)phthalocyanine compound in which each of at least five of the peripheral carbon atoms in the 1, 4, 5, 8, 9, 12, 13 or 16 positions (the "3,6-positions") of the phthalocyanine nucleus, as shown in Formula I, is linked by an atom from Group VB or Group VIB of the Periodic Table, other than oxygen, to a carbon atom of an organic radical. In preferred compounds each of the eight 3,6-positions is linked by an atom from Group VB or Group VIB, especially sulphur, selenium or nitrogen, to an organic radical.

Abstract: A barrier for confining an area of monomolecular film on a Langmuir trough comprises a first barrier portion consisting of a transverse part and a longitudinal part and a second barrier portion connected at its ends to the ends of the first barrier portion and having two further longitudinal parts, one close to the first longitudinal part and the other further away. By altering the position of another transverse part joining the two further longitudinal parts the area enclosed is varied by changing the length of the longitudinal part close to the first longitudinal part and altering the length of the longitudinal part further away by an amount such that the sum of the two altered lengths remains constant.

Abstract: An anchorage for elastic lingoes 11 of a loom harness comprises a plurality of rail members 12 each extending across the loom and arranged adjacent and parallel to one another in to a support so as to be separately removable and replaceable with their lingoes 11 still attached. The loom is easier to clean than conventional looms.

Abstract: Electrophoresis of a colloidal suspension of a semiconducting sulphide, sulphoselenide, selenide or telluride in an aqueous medium produces a thin pin-hole-free film on a surface of a substrate. The film may be employed in solar cells.

Abstract: Application of heat preferentially to one surface of a film of a semiconducting sulphide, sulphoselenide, selenide or telluride to establish a temperature differential between the surfaces of the film improves the electrical and photochemical properties of the film. The film may be employed in solar cells. Preferably the film is prepared by electrophoresis of a colloidal suspension of the semiconductor in an aqueous medium.