A method for injection molding of a weld line free minus power lens element comprises injecting a melt of thermoplastic material at a temperature higher than a glass transition temperature (Tg) of the thermoplastic material in an initial molding cavity delimited by two facing mold inserts, wherein the melt of thermoplastic material comprises at least one UV absorber. During the injecting, the two facing mold inserts are moved toward one another to define a final molding cavity whose volume is less than that of the initial molding cavity. After cooling and disassembling of the two facing mold inserts, the weld line free minus power lens element is recovered. One of the two facing mold inserts comprises a flat surface facing the initial molding cavity, thereby to form a flat surface on one side of the weld line free minus power lens element. The other of the two facing mold inserts comprises a convex surface facing the initial molding cavity, thereby to form a concave surface on an opposite side of the weld line free minus power lens element.

A laser welding system for joining first and second thermoplastic workpieces, and including a clamp, an actuator, and a laser source. The clamp includes first and second clamping structures positioned together to engage opposite sides of the workpieces when they adjoin each other. The first clamping structure has a non-flat or irregular surface, facing the first workpiece. The actuator causes the clamping structures to press the first and second workpieces together. The laser source applies laser radiation having a wavelength of 2 microns toward the workpieces to be joined, while they are pressed together by the clamp, to melt irradiated portions of the workpieces to one another. The first clamping structure transmits substantially all of the energy of the laser radiation through the material. The first workpiece has a non-flat or irregular surface facing the first clamping structure, which substantially conforms with the surface of the first clamping structure.

A laser welding system for joining first and second thermoplastic workpieces, and including a clamp, an actuator, and a laser source. The clamp includes first and second clamping structures positioned together to engage opposite sides of the workpieces when they adjoin each other. The first clamping structure has a non-flat or irregular surface, facing the first workpiece. The actuator causes the clamping structures to press the first and second workpieces together. The laser source applies laser radiation having a wavelength of 2 microns toward the workpieces to be joined, while they are pressed together by the clamp, to melt irradiated portions of the workpieces to one another. The first clamping structure transmits substantially all of the energy of the laser radiation through the material. The first workpiece has a non-flat or irregular surface facing the first clamping structure, which substantially conforms with the surface of the first clamping structure.

A laser welding system is directed to simultaneously joining respective layers of a first bag and a second bag. The system includes a first film layer adjacent to a second film layer for forming the first bag, and a third film layer adjacent to a fourth film layer for forming the second bag, each layer of the plurality of film layers being made of a thermoplastic material that absorbs laser radiation having a wavelength of about 2 microns. A non-absorbing carrier film layer is positioned between the second film layer and the third film layer, the non-absorbing carrier film layer being made of a material that transmits substantially all energy of the laser radiation. A laser source applies the laser radiation toward portions of the plurality of film layers to be joined, forming the first bag generally simultaneously with the second bag.

A laser welding system is directed to simultaneously joining respective layers of a first bag and a second bag. The system includes a first film layer adjacent to a second film layer for forming the first bag, and a third film layer adjacent to a fourth film layer for forming the second bag, each layer of the plurality of film layers being made of a thermoplastic material that absorbs laser radiation having a wavelength of about 2 microns. A non-absorbing carrier film layer is positioned between the second film layer and the third film layer, the non-absorbing carrier film layer being made of a material that transmits substantially all energy of the laser radiation. A laser source applies the laser radiation toward portions of the plurality of film layers to be joined, forming the first bag generally simultaneously with the second bag.

A method of forming a balloon for a medical device is provided including extruding a cylindrical tube of silicone material, partially curing the cylindrical tube, inflating the cylindrical tube, and fully curing the balloon. The cylindrical tube is partially cured by exposing the cylindrical tube to a first ultraviolet light source. The cylindrical tube is inflated within a mold to form the balloon. The balloon is fully cured by exposing the balloon to a second ultraviolet light source.

The invention relates to an apparatus and to a method for establishing a connection having material continuity or having material continuity and shaping matching or for separating such a connection of at least one metal or ceramic component and of a component formed from or by a thermoplastic polymer in which the components to be joined together can be pressed together by a pressing device having a counterholder and a plunger. A heating device is present at the plunger and/or at the counterholder or acts there. A heating of the at least one metal or ceramic component up to above the softening temperature of the component formed from or by polymer can be achieved with the heating device, with the heating device being having at least one electrical resistance heating element that is covered by an electrically insulating, preferably ceramic, protective film, and/or having at least one laser beam that is directed to the metal component(s) within the joining region, and/or having at least one inductor present at the plunger and/or at the counterholder for the inductive heating of the meal component(s).

The invention relates to an apparatus and to a method for establishing a connection having material continuity or having material continuity and shaping matching or for separating such a connection of at least one metal or ceramic component and of a component formed from or by a thermoplastic polymer in which the components to be joined together can be pressed together by a pressing device having a counterholder and a plunger. A heating device is present at the plunger and/or at the counterholder or acts there. A heating of the at least one metal or ceramic component up to above the softening temperature of the component formed from or by polymer can be achieved with the heating device, with the heating device being having at least one electrical resistance heating element that is covered by an electrically insulating, preferably ceramic, protective film, and/or having at least one laser beam that is directed to the metal component(s) within the joining region, and/or having at least one inductor present at the plunger and/or at the counterholder for the inductive heating of the meal component(s).

The present disclosure provides a mold for molding a polyurethane condom, and methods for manufacturing and using the mold. The mold (200) has a surface roughness of 0.2 or less, is formed from a thermoplastic polymer having a surface tension of 10-35 mN/m. The mold (200) for molding a polyurethane condom is prepared by injection molding the thermoplastic polymer. When the mold (200) is used, the mold (200) is hung vertically and dipped in an emulsion containing a polyurethane resin to obtain a dipped mold (200), then the dipped mold (200) is removed and dried to form a polyurethane film on its surface, and then demolded to obtain a polyurethane condom (100). The condom formed by the mold (200) is thin and has excellent flexibility and strength, satisfying the market demand for the product.

A method for avoiding the entrapment of air bubbles (5) in a lens forming material, in particular in a low viscosity lens forming material, in an ophthalmic lens manufacturing process using mold halves (2; 3) each having a lens forming surface (21; 31) comprises electrostatically charging a predetermined portion of the lens forming surface (21; 31) of the mold half (2; 3) prior to the predetermined portion of the lens forming surface (21; 31) coming into contact with the lens forming material (4).