摘要:
A system is disclosed for synchronizing a free-swinging oscillator to a reference signal of a substantially lower frequency. A regulating circuit connects to the oscillator to control the frequency thereof. A quartz oscillator is provided for producing the reference signal. The reference signal is subsequently connected to a frequency multiplier and/or frequency divider, an amplifier and a pass band filter. An output signal from the pass band filter is fed to a harmonics mixer connected to the free-swinging oscillator and which produces a pattern of harmonics. A selective amplifier feeds an intermediate frequency obtained from the harmonics mixer to the regulator circuit. A filter also connected to the quartz oscillator produces harmonics which are also coupled to the regulating circuit. By phase or frequency comparison the regulating circuit adjusts the running frequency of the free-swinging oscillator.
摘要:
Nacreous pigments having improved light fastness are based on mica platelets coated with titanium dioxide and, optionally other additional metal oxides. These pigments carry an additional thin manganese oxide layer. The pigments are prepared in a process wherein mica is coated in aqueous suspension with one or more titanium dioxide hydrate layers and, optionally, with further metal oxide layers, mixed with the titanium dioxide hydrate or separately therefrom, and then is washed, dried and calcined. The process further comprises precipitating an additional layer of manganese hydroxide onto the base pigment, either directly after coating with the titanium dioxide hydrate and/or metal oxide layers or after the calcination thereof. The flakes are the washed, dried and calcined.The new pigment can be used for pigmenting plastics, lacquers, paints and cosmetics, inter alia.
摘要:
A process for rendering nacreous pigments hydrophobic, the pigments being based on mica platelets coated with metal oxides, comprises coating the pigments in aqueous suspension with a chromium (III) or aluminum (III) hydroxide or silicate, and then treating the coated pigments with a solution of a hydrocarbon carboxylic acid having more than four carbon atoms per carboxyl group.
摘要:
Nacreous pigments comprise a mica platelet coated with a first layer of a metal oxide and a second layer of chromium(III) oxide, wherein the chromium oxide layer further contains at least 0.05 mol % of phosphate ion based on the number of moles of chromium ion therein. Because of the phosphate ion, the chromium layer is continuous and essentially crack-free even at larger thicknesses, and contributes to the interference effect. The pigments are particularly useful as lustrous agents in cosmetics.
摘要:
Colored material-containing pearlescent pigments based on mica flakes coated with metal oxide contain as colored material, a colored aluminum lake which is fixed as a water-insoluble compound on the surface of the pigment particles, the lake being formed from a precipitated aluminum hydroxide layer, wherein the aluminum hydroxide layer forming the colored lake contains 1 to 50% by weight of a compound of the formula ##STR1## wherein X is hydroxy or carboxy, Y is hydrogen or alkyl or alkenyl of 10 to 20 carbon atoms and Z is hydrogen, or alkyl or alkenyl of 10 to 20 carbon atoms, or the grouping ##STR2## said compound having a molecular weight of at least 150 and a solubility in water at a pH of 5-9 of at least 0.05 g/l, and said compound being precipitated onto the flakes together with the aluminum hydroxide layer. A process for the production of these pigments is also provided, as are cosmetics containing them.