Ceran Color

Germany, produced two types of this glass-ceramic, characterized by different optical transmission (Pannhorst 1992 and Nass et al., 1995). The products are called Ceran Color and Ceran Hightrans . 

Fig. 3.12. Typical transmissions of Ceran Color and Ceran Hightrans for 4 mm sample thickness. The higher IR transmission of Ceran Hightrans supports the overall heating performance...

Schott started its cooktop panel production with Ceran Color (purple lavender tint). Today Schott produces a variety of cooktop panels made of different glass ceramic types, of which the two types ... 

Ceran Color, formerly produced at Schott AG, was colored by a mixture of Fe203, NiO, CoO, and Mn02. Ceran Hightrans is colored with V2O5, does not have high Fe2 03 levels, and exhibits, therefore, a substantially improved infrared transmission. 

The Ceran glass-ceramic is colored and is designed for applications in cooker surface panels. 

While in the last thirty years only black cooktop panels (Fig. 3.3 left) have been marketed, recently white and cream cooktop panels have been introduced. This development responds to the request for more differentiation. As a result, Schott has started a campaign to introduce a number of new cooktop panels which are colored in the bulk. White and cream-colored cooktop panels are based on keatite s.s. crystal containing glass ceramics (see the Ceran Arcticfire cooktop panel in Fig. 3.3 right). The variety of colors available to date can be embellished with a broad selection of decoration colors (see Fig. 3.4). 

As mentioned above, Ceran glass ceramic cooktops are decorated with ceramic colors of varying chemical composition to achieve an extensive color selection. 

The calculations show that only a very thin color layer (< 5-7 pm) can be applied so as to adhere, since otherwise the tension threshold is exceeded, leading to chipping-off of the composite. This makes it necessary to produce colors that are opaque at such minimum layer thicknesses, which can lead to difficulties in view of pigment particle sizes often exceeding 10 pm. Another difficulty is that the upper cooktop surface of the colors deemed generally suitable for decoration of Ceran cooktop panels must also withstand other - sometimes extreme - thermal, mechanical, and chemical loads (see also Sect. 3.2). 

Table 3.6. Physical properties of Ceran decoration colors...

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