Лако-красочные материалы — производство

Inorganic pigments can be classified from various points of view. The classification given in Table 1.2 (for standards see Table 1.1, “Coloring materials, terms”) follows a system recommended by ISO and DIN; it is based on coloristic and chemical con­siderations. Further methods for classification are shown in Section 1.2.1. As in many classification schemes, there are areas ofoverlap between groups so that sharp boundaries are often impossible. In this book white pigments are described in Chap­ter 2, colored pigments in Chapter 3, black pigments (carbon black) in Chapter 4 and specialty pigments in Chapter 5.

Tab. 1.2: Classification of inorganic pigments.

Definition

the optical effect is caused by nonselective light scattering (examples: titanium diox­ide and zinc sulfide pigments, lithopone, zinc white)

the optical effect is caused by selective light absorption and also to a large extent by selective light scattering (examples: iron oxide red and yellow, cadmium pigments, ultramarine pigments, chrome yellow, cobalt blue)

the optical effect is caused by nonselective light absorption (examples: carbon black pigment, iron oxide black)

the optical effect is caused by regular reflection or interference

regular reflection takes place on mainly flat and parallel metallic pigment particles

(example: aluminum flakes)

regular reflection takes place on highly refractive parallel pigment platelets (example: titanium dioxide on mica)

the optical effect ofcolored luster pigments is caused wholly or mainly by the phe­nomenon ofinterference (example: iron oxide on mica)

the optical effect is caused by the capacity to absorb radiation and to emit it as light ofa longer wavelength

the light oflonger wavelength is emitted after excitation without a delay (example: silver-doped zinc sulfide)

the light oflonger wavelength is emitted within several hours after excitation (example: copper-doped zinc sulfide)

1.1.2