U.S. patent number T984,007 [Application Number 05/928,293] was granted by the patent office on 1979-07-03 for jig-saw puzzles. This patent grant is currently assigned to Imperial Chemical Industries Limited. Invention is credited to John C. Richardson.

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United States Patent	T984,007
Richardson	July 3, 1979

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Jig-saw puzzles

Abstract

a jig-saw puzzle comprises interfitting pieces (1, 2, 3, 4) which when fitted together side-by-side form a three-dimensional upper surface simulating for example hills and valleys. Each piece is formed of a molded open or closed cell thermoplastics foamed core 7 sandwiched between upper and lower thermoplastics skins 8a and 8b. A printed sheet 9 is stuck on to the upper skin 8a. The skins 8a and 9a may be made from any conventional moldable thermoplastics. A preferred thermoplastics is a copolymer of propylene with from 5 to 20% by weight of ethylene made by injecting ethylene into the final stages of an otherwise propylene homopolymerization. The core may be made of the same or different plastics as the skins. Polyurethane is a preferred core material. The printed sheet, which may be paper or fabric, may be stuck on to the upper sheet with adhesive or by penetration or fusing of the skin material into the sheet during molding of the pieces.

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Inventors:	Richardson; John C. (Hitchen, GB2)
Assignee:	Imperial Chemical Industries Limited (London, GB2)
Family ID:	26259504
Appl. No.:	05/928,293
Filed:	July 26, 1978

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Related U.S. Patent Documents

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	Application Number	Filing Date	Patent Number	Issue Date
	810372	Jun 27, 1977

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Foreign Application Priority Data

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Jul 9, 1976 [GB]			28677/76

Current U.S. Class:	273/157R; 156/220; 264/132; 264/321; 264/45.1; 264/DIG.83; 434/76
Current CPC Class:	A63F 9/10 (20130101); A63F 2009/1077 (20130101); Y10S 264/83 (20130101); Y10T 156/1041 (20150115); A63F 2250/183 (20130101)
Current International Class:	A63F 9/06 (20060101); A63F 9/10 (20060101); A63F 009/12 ()

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