Patent GB-1287661-A (GB)
Title: Method and apparatus for preparation of laminar structures
IPC: A23P20/20
Filed: 1970-05-14
Abstract: 1287661 Laminating process KANEGAFUCHI BOSEKI KK 14 May 1970 [15 May 1969 (2)] 23421/70 Heading B5N A method of making a regular multi-layer structure consisting of layers of a viscous liquid and natural or man-made sheet materials, using a plurality of receptacles 27 each being a generally rectangular open-topped, flat bottomed vessel surrounded by a continuous wall consisting of two side walls and two end walls extending upwardly from the flat bottom, and an endless horizontal conveyer 20 containing at least one straight section 23, 24 and at least one curved section 25, 26 by a sequential series of steps comprising:-moving the receptacles on the conveyer and bringing adjacent receptacles into end-to-end contact as they travel along a straight section by decreasing the speed of a travel of a given receptacle relative to the speed of travel of the following receptacle as the receptacles are carried forwardly on this straight section during their circulatory travel on the conveyer; moving the receptacles forward at constant speed while in contact; dispensing the viscous liquid at a predetermined rate from a dispensing means 21, 22 uniformly for the entire inner breadth of the said receptacles-into each receptacle as it passes under said dispensing means to form a layer of said liquid within said receptacle; thereafter increasing the travel speed of a given receptacle relative to the travel speed of the following receptacle to open up an interval between the respective receptacles after passing under the dispensing means, the interval being such that the receptacles will not interfere with each other through a subsequent curved section of the conveyer; thereafter depositing a sheet of natural or man-made material on the entire surface of the layer of said liquid formed in each receptacle at such a time when the thickness of the layer of liquid has become uniform over the receptacle under gravity e.g. at stations 2 and 3 and repeating the aforesaid sequential series of steps an appropriate number of times. The four walls of each receptacle may be perpendicular; alternatively the leading wall of each receptacle may be inclined outwardly from bottom to top. The conveyer means may comprise a plurality of independently driven sections, a preferred conveyer means comprising a plurality of roller conveyers 1. The apparatus used in the method is equipped with guide wings 13 and 14 each consisting of a belt 18 to centre the receptacles and to adjust the speed of travel of a receptacle relative to that of the adjacent receptacles. The liquid dispensing means of the apparatus comprises a nozzle plate 33 provided with a plurality of nozzles 31 formed in rows such that the nozzles of one row are staggered with respect to the nozzles of the adjacent rows, the nozzles projecting beyond the plate. A typical product of the invention comprises layers 17 of viscous liquid, separating sheets 15 of paper and reinforcing sheets of fabric 16, said product being heated to cure the liquid and the paper separating sheets being washed out to provide a plurality of fabric reinforced sheets resembling chamois leather, the liquid used being typically a mixture of starch and polyvinyl alcohol suitable for the formation of a porous polyvinyl acetal. In an embodiment of the method of the invention all the sheets used are of a separating material.