Source: {"pile_set_name": "USPTO Backgrounds"}

The practice of putting material into the interior of tire casings is well known. The interior of tire casings have been sprayed so as to provide a lubricant and thereby reduce friction between the interior of the tire casing and an inner tube; have been sprayed to assist the curing of the interior portions of a tire casing; have been sprayed to introduce a sealent material about the interior of the tire casing so as to reduce the deflation of the tire when punctured by permitting the sealent material to flow to the puncture opening; and also, tires have been coated, as distinct from spraying, with material for the purpose of providing a sealent or even to increase the thickness of the tire so as to reduce the possibility of penetration into the interior of the tire by sharp objects.
Such procedures and the products produced thereby do not distribute the material within the tire casing evenly about the inner periphery of the tire so as to insure that the balance of the tire will not be modified by the material which is being added. This is not significant where a very thin coat of material is sprayed onto the interior of the tire but when the layer of material introduced into the tire is distributed so as to provide a thickness of material, as distinct from a mere coating of material, the problem of even distribution of the material becomes significant in maintaining the balance of the tire. In addition, there is the problem of distributing the material across the inner periphery of the tire casing and along contiguous sidewalls of the inner periphery to provide a layer or liner of material which is of substantially uniform thickness