Abstract: A method for forming a molecularly oriented thermoplastic container, wherein a thermoplastic blowable shape such as a parison or a blown pre-form is blown to the configuration of the container within a blow mold cavity. The temperature of the blowable shape is within a range conducive to molecular orientation during the blowing step, which is rapidly performed by hot blow air at a temperature between about 100.degree. to 400.degree. F. Typically, a blowable shape formed of polyethylene terephthalate is blown while the shape is at a temperature within the range of 165.degree. to 200.degree. F. by the introduction into the shape of hot blow air at a temperature within the range of about 165.degree. to 200.degree. F. If desired, the blowable plastic shape may be axially stretched mechanically in addition to being blown in order to improve the biaxial orientation of the thermoplastic material in the final article.

Abstract: Apparatus is disclosed for heating thermoplastic parisons to a substantially uniform temperature across their wall thickness prior to a blow molding operation. The parisons are rotated about their longitudinal axes while being conveyed adjacent a thermal conditioning means, which includes vertically spaced radiant heating elements and a gaseous cooling source. The heating elements radiate infra-red rays having a wave length to penetrate and heat the full thickness of the parison wall; whereas the gaseous cooling source directs a stream of air onto the surface of the parison facing the heating elements to prevent the parison surface from being overheated. Additionally, each of the heating elements may be individually regulated so that the parisons can be differentially heated along their axes to control the wall thickness of the final blown articles.

Abstract: A method is disclosed for conditioning strain hardenable thermoplastic materials, such as polyethylene terephthalate, so that a highly developed strain crystallized morphology may be established during a blow molding operation. In the method, a thermoplastic parison is heated to a temperature in a range conducive to molecular orientation and then initially stretched at that temperature. Next, the stretched parison is cooled to a temperature slightly below glass transition temperature and stretched further at the reduced temperature. The combined stretching in these two separate phases is chosen to condition the material so that it is either on the verge of being strained hardened or has actually started strain hardening. Thereafter, the parison may be again heated to a temperature conducive to molecular orientation and blown; to a final article, with the resulting expansion of the material during the blowing operation achieving the desired strain crystallized morphology and strain hardening.

Abstract: An improvement is provided in packages in which a thermoplastic bottle has a separate support base integrally and securely attached thereto for supporting the bottle in an upright position. The bottle includes a convex bottom portion incapable of supporting the bottle in a stable upright position and a peripheral sidewall above the bottom portion. The support base includes a lower package support surface and a generally tubular sidewall extending upwardly from the support surface to telescopically enclose a portion of the bottle peripheral sidewall. The specifically disclosed improvement essentially resides in providing a pre-decorated tubular label of either a closed cellular thermoplastic or a clear thermoplastic film in heat shrunk snug substantially contaminant precluding, peripheral engagement with externally exposed surfaces of the bottle peripheral sidewall and the tubular sidewall of the base and covering the juncture of the base and the bottle.

Abstract: A method and apparatus for molding an end portion of a tubular thermoplastic parison prior to a blow molding operation to form a parision finish and an annular support flange. The method includes closing a laterally movable, sectional mold onto a circumferential section of a parison so that at least one end portion of the parison extends out of the mold. The extending end portion of the parison is then thermally conditioned to a deformable temperature and thereafter the parison is axially displaced to telescopically insert the thermally conditioned end portion within the mold into general radial alignment with annular, longitudinally spaced finish and support flange cavities.

Abstract: A method of and apparatus for making a concave bottom on a blown thermoplastic container, and a container having such a bottom. A blowable pre-form is initially expanded against a composite mold surface defined by the end faces of a plurality of concentric tubes surrounding a central actuating rod. The rod and the tubes are initially telescopically positioned to define a composite concave surface, so that a first convex bottom is blown. Subsequently, the rod and tubes are actuated telescopically to progressively invert the convex bottom to a concave shape. The end faces of the tubes may be grooved to define reinforcing ribs in the concave bottom wall, if desired.The container has a concave bottom wall of improved resistance to deformation under internal pressure. This is accomplished by forming a support ring at the juncture of a pair of oppositely directed inner and outer bottom walls, the juncture of the walls defining an included angle which is equal to or less than 90.degree.

Abstract: A method and apparatus are disclosed for molding plastic articles, wherein the method includes the steps of filling a mold cavity at a first station with heated flowable plastic material under relatively low pressure from a first pressure source and then displacing the mold to a second station where the plastic material is cooled under pressure from a second pressure source. During the displacing step, the mold is conveyed along an arcuate path and the mold orientation is maintained. The apparatus includes a cantilevered core pin concentrically positioned in the mold cavity and a set of radially biased neck rings which preferably open automatically under a constant biasing force to release the neck of a molded article after the core pin is withdrawn from the article.

Abstract: A method is disclosed for reinforcing bottles with a tubular netting embedded in an exterior surface of the bottle. A tubular netting section is initially compressed in an axial direction to increase its diameter. The compressed netting is positioned over a preformed parison of a thermoplastic material. The compressed netting is then released to re-expand axially and contract diametrically, until the netting contacts the parison. The parison is finally transferred to a blow mold and blown into a finished bottle. During the blowing operation, the netting is embedded into and reinforces the walls of the blown bottle. Depending upon the materials from which the netting and bottle are formed, the netting may also weld to the bottle wall to further increase the strength of the bottle.

Abstract: There is disclosed a method for attaching a polyethylene sleeve label to a polyethylene bottle, the label having on the outer surface thereof means for absorbing heat in local, discrete areas of the label at a rate greater than that of other areas of the label; and means for welding the label to the body at the junction of the outer surface of the body and the inner surface of the label, adjacent the local heat-absorbing areas.