Abstract: A record book or pad and a method of manufacturing such a book or pad has a stack of sheets in sets A. Each set A consists of a primary sheet P disposed between secondary sheets OS and US. Both faces of the sheet P are provided with a reactive coating 4 of duplicating material and each face of the secondary sheets OS and US which opposes the primary sheet P in the set is provided with reactive coatings 5 of duplicating material. When a marking is applied to the sheet OS for recording a message, pressure from that marking transfers through the sheet OS causing the coatings 4 and 5 between the sheets OS and P to inter-react and form a duplicate marking on a one face of the sheet P. Similarly when a marking is applied to the secondary sheet US, pressure from that marking transfers through the sheet US causing the coatings 4 and 5 between sheet P and US to inter-react and form a duplicate of the marking on the second face of the sheet P.

Abstract: A record book or pad and a method of manufacturing such a book or pad has a stack of sheets in sets A. Each set A consists of a primary sheet P disposed between secondary sheets OS and US. Both faces of the sheet P are provided with a reactive coating 4 of duplicating material and each face of the secondary sheets OS and US which opposes the primary sheet P in the set is provided with reactive coatings 5 of duplicating material. When a marking is applied to the sheet OS for recording a message, pressure from that marking transfers through the sheet OS causing the coatings 4 and 5 between the sheets OS and P to inter-react and form a duplicate marking on a one face of the sheet P. Similarly when a marking is applied to the secondary sheet US, pressure from that marking transfers through the sheet US causing the coatings 4 and 5 between sheet P and US to inter-react and form a duplicate of the marking on the second face of the sheet P.