Rokus van Blokland
Corry van Blokland Mobach

Clocks and blackboards
Clocks have been a solid component within the Sio collection. The first design with square digits is from 1953, the round clock with coloured digits dates from 1965.
Over the years this clock has been produced in very large numbers.

The blackboards have also had a fixed position in the collection.
The Classic blackboard has changed over time in drawings (by Corry) which can be drawn on.


Round clock with coloured number plates, arranged in spectrum.


Square Clock, had coloured blocks with numbers.


Photo: Piet Mobach

1971 Production clock at factory, Sio Vroomshoop

Photo in an article from Sikkens paint factory about companies, like Sio which use their paint.


Just painted circles, ready for production. The digits are printed on the coloured circles after they are connected to the number plate.

1974 Design new box
1974 Clock with new box

Photo box by Kees Pot

1975 Clock

The clock hands are provided with a rotating mechanism.

1975 Clock with blackboard

1978 Clock with box

1979 Drawings Count-Clock

1979 Design drawings Count-Clock
1979 Count-Clock

1977 Blackboards

Blackboards in a form that invites to draw something.

1977 Boy and girl blackboards

1978 Blackboard

Blackboard which can be used to draw nice faces. It is also used in bars and restaurants to show food and prices.