Metallic flake pigments

Other NAD microspheres are composed of styrene, MMA, hydroxyethyl acrylate, acrylic acid and acrylonitrile and are blended with acrylic copolymers and melamine/formaldehyde resins [341,342]. Particles of this polymer are used as rheology modifiers to prevent sagging in automotive coatings and for controlling the orientation of metal flake pigments. 

Metallic-Flake Pigment Ultramarine-Blue Pigment... 

Aluminium powder has been used as a metallic flake pigment. The term Aluminium bronze powder also seems to refer to this... 

Bieganska et al. (1988) as metal flake pigment Synthetic analogue... 

Plastics pigmented with aluminum can be recycled and recycled PO may be optically improved by addition of aluminum pigments. Among recent developments Obron Atlantic offers Mastersave an easily dispersed pelletized 80% aluminum pigment concentrate, which usually does not require predispersion. They are available as pastes (a slurry with mineral spirits). The major use of metallic flake pigments is in protective and decorative coatings. 

Materials pigmented with interference pigments can be characterized. by color data obtained from spectral reflectance factors at specific illumination and detection angles (15). Similarly, color information for metal flake pigmented materials, has been obtained on... 

Standard practice for multiangle color measurement of metal flake pigmented materials, ASTM Standard, Book of Standards, Vol. 06.01 ASTM E2194-03, ASTM International, West Conshohocken, PA, 2009. Standard test method for evaluation of color for thermoplastic traffic marking materials, ASTM Standard, Book of Standards, Vol. 06.02 ASTM D4960-08, ASTM International, West Conshohocken, PA, 2008. Colorimetric evaluation of colour coordinates and colour differences according to the approximately uniform CIELAB colour space, DIN Standard DIN 6174, DIN, Berlin, 2007. 

Mearlin metallic colors produce metallic shades and effects without the use of metal flake pigments. Unlike many of the latter, Mearlin metallic pigments do not tarnish or oxidize, and are non-arcing. 

A novel application for the metal flake based materials is in security outlets because they are non-photocopyable. Pigments from Flex Products have been used by SIPCA to produce optically variable green-to-black inks for printing secure images on US dollar bills. ... 

Metal effect pigments (Fig. 71 B) consist of small metallic flakes (mainly aluminum or Cu/Zn bronze) which act as small mirrors that reflect almost all of the incident light. 

Reduction of suitable aqueous metal salts by electroless plating yields metal-coated mica pigments. They are less expensive than noble metal flakes (Au, Ag) and their brilliant metallic appearance is comparable with that of metallic flakes [5.192], [5.193],... 

Definition. Metal effect pigments consist of flakes or lamellae of aluminum (aluminum bronzes), copper and copper-zinc alloys ( gold bronzes ), zinc, and other metals (DIN 55943, 55944 FSO 4618-1). 

The metal effect depends not only on particle size and particle size distribution, but also on the orientation of the metal flakes within the coating film, particle shape, the transparency of the binder matrix, and the presence of colored pigments or dyes. 

Metallic Pigments. These pigments are metal flakes of various sizes made up of aluminum, copper, zinc, and/or their alloys. The aluminum flakes develop the silver metallic colors, whereas the copper, zinc, and aluminum alloys produce the gold, copper, brass, and bronze colors. The metal effect is modified, not only by shape and size, but also by perticle size distribution within a given product. Since aluminum, in particular, as a fine dry powder, can form explosive mixtures with air, most of these materials are commercially available in paste or liquid concentrates. In addition, surface treatments of these materials enhance their appearance and performance. Flakes of other metals, such as stainless steel, are used for surface protection purposes such as corrosion resistance and electrical conductivity. 

The film is continuously coated from the front or backside by rolls or knife coating. For small-volume items frequently gravure or a roller coater is used. All these applications result in an even orientation of the metallic flakes parallel to surface. The frequently used spraying technique has a disadvantage in this case because, due to its high viscosity, the metal pigment shows only little orientation. 

Metal effect pigments regular reflection takes place on mainly flat and parallel metallic pigment particles (example aluminum flakes)... 

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