These dyes are finely ground and are available as a paste or a powder that gets dispersed in water. Any indications which is believed to be non relevant shall be regarded as a discontinuity and shall be re-examined to verify whether or not actual defects are present. As a result, great efforts have been made in recent years to develop leather dyes which are "ideal" from the standpoint of application and which help the tanner to meet the enhanced quality specifications. The chemical types are azo and anthraquinone giving a complete colour range. Difficulties with different substrates. The dye composition also preferably contains a viscosity depressant which serves as a carrier for the dye. There are two major types of dyes - natural and synthetic dyes.
The chemical types are azo and anthraquinone giving a complete colour range. The dyeing of protein substrates as textiles wool presents less of a challenge, since the initial fixation of molecules by salt-linkages can be re-arranged by promoting migration of the dyes within and throughout the substrate at high temperatures at the boil. They are mostly used for wool which gets a good color fastness after treatment with mordant dyes. Areas of tone-in-tone variation paler or deeper tone are more acceptable than patches of distinctly different color. Any indications which is believed to be non relevant shall be regarded as a discontinuity and shall be re-examined to verify whether or not actual defects are present. Table 1 Classification of textile fibres.
Because these H bonds and van der Waals' forces are weak and short range, a molecule must be large to interact and fix with them. Materials corresponding to these five examples of biodegradable nonionic surfactants are marketed, respectively, as:. Has anyone reported any allergies to this product? So far, the problem of variation in dye affinity towards different substrates has not been overcome. Smaller dye molecules like the ones in direct dyes will simply sit under cuticle and rinse out within weeks. Efficient lipid staining in plant material with Sudan Red 7B or Fluoral Yellow in polyethylene glycol-glycerol. A representative preferred isoparaffinic solvent particularly having the above chemical and physical characteristics is the solvent marketed as "Isopar M" by Exxon.
The red-visible dyes employed according to the invention are liquid red azo dyes containing C 5 -C 12 alkyl-beta-naphthols. Table 2 Approximate relative strengths of bonding between a dye and a fabric. Like other sulfur dyes, their structures are variable and largely unknown. Retanning System No retan - Blank. However, they are the subject of much research and interest and are being developed for a variety of purposes. Caution - Photochromic lenses shall not be worn during examination.