Metallic pigments pressing

The slurry is then separated by particle size and the mineral spirits squeezed out by filter presses. The resulting press cake contains 70-90% metal pigment and undergoes the following additional steps ... 

The pressing processes do not provide any dispersing action for the metallic pigments. The premixed components are only brought into the desired form and then sintered (melted). The homogenous appearance therefore depends totally on the preblend of all powdered components. 

The metal pigments, gold bronze as well as aluminum, are supplied in the form of powders, pastes (including solvents), granules (including resins), suspensions (VMPs), color concentrates or even press-ready printing inks. 

Preformed Two-Piece Metal Containers. Ink vehicles for letterset printing of two-piece aluminum or steel containers are mainly based on special polyester vehicles used in conjunction with melamine cross-linkers. Short cycle ovens which dry inks in 1—5 seconds are now used and operate at temperatures as high as 350 °C. The rheology of these inks must be adjusted to the unique geometry of the press. Desired rheological properties are achieved by the use of additives as weU as extender pigments. 

Figure H.3 shows a typical metallized hot stamping foil. The carrier film supports the decorative coatings until they are pressed on the plastics part. A lacquer coating is passed over the releasing layer to provide protection for the metal foil. If paints are used, the lacquer and paint pigment are combined into one layer. The bottom layer functions as a heat- and pressure-sensitive hot-melt adhesive. Heat and pressure must have time to penetrate the various film coating and layers to bring the adhesive to a liquid state. Before the carrier film is stripped away, a short cooling time is required to ensure that the adhesive is solidified.

A method of marking plastics in which a special pigmented, dyed, or metallized foil is pressed against the plastic article by a heated die, welding selected areas of the foil to the article. The term also includes a process of impressing inked type into the material when the type is heated. 

Uses Polyester-acrylic in wet lithographic inks and coatings on paper, plastic, and metal good pigment wetting in lithographic and letter press paste inks Features Low odor low extractability... 

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