摘要:
In a process for the manufacture of mouldings, especially optical lenses, specifically contact lenses (CL), a starting material that is crosslinkable by the impingement of suitable energy is introduced into a mould (1) having a cavity (15), which mould is at least partially permeable to the energy concerned. The starting material is introduced into the cavity in a still at least partially uncrosslinked state, the mould cavity determining the shape of the moulding (CL) to be produced. By means of impingement of the energy concerned, the starting material is crosslinked to an extent sufficient for it to be possible for the moulding (CL) to be released from the mould. The filling of the mould cavity is carried out in the starting material that is still at least partially in the uncrosslinked state.
摘要:
A measured amount of a material that is crosslinkable by impingement of a suitable form of energy, especially UV light, is introduced into a two-part mould of which cavity determines the shape of a moulding to be produced. The two mould halves are held a small distance from one another so that a thin annular gap is formed between them, which gap is in communication with the mould cavity and through which gap excess material can escape. The crosslinking is triggered by impingement of the selected form of energy, the impingement being spatially restricted to the cavity by suitable masking so that material disposed outside the mould cavity is not crosslinked. In that manner mouldings are obtained that do not require subsequent mechanical processing, and the mould is reusable. The process is especially, but not, however, exclusively, suitable for the manufacture of contact lenses.
摘要:
The present invention describes novel statistical copolymers and the preparation and possible uses thereof. Copolymers are described that are water-soluble and cross-linkable and that comprise the copolymerisation product of a monomer mixture consisting substantially of a vinyl lactam (a) and at least one further vinyl monomer (b) of a different type selected from the group consisting of hydrophobic, hydrophilic and functional vinyl monomers, wherein the monomers are present in the copolymer in the form of statistically distributed building blocks, and, if a functional vinyl monomer is present as a building block in the copolymer, that building block is, where appropriate, modified with a reactive vinyl monomer (c), the reactive vinyl monomer (c) being linked to a building block of a functional vinyl monomer with retention of its vinylic group and with the formation of a covalent bond.
摘要:
The blister pack comprises a base portion and a cover layer. The base portion comprises a hollow chamber that contains a soft hydrophilic contact lens and a sterile aqueous preserving solution, and a substantially flat flange that extends right round the outside of the hollow chamber. The cover layer is releasably sealed to the flange in a sealing zone that extends right round the circumference of the hollow chamber. The flange comprises a grip region that extends from one side of the hollow chamber beyond the sealing zone and is covered by a corresponding grip region of the cover layer but is not sealed thereto. The hollow chamber comprises a dish-shaped main chamber and, adjoining the side of that main chamber, a secondary chamber in the shape of a channel tapering on all sides away from the main chamber, the main chamber making a smooth transition into the secondary chamber, and the main chamber and the secondary chamber together having a drop-shaped contour in the plane of the flange, the tip of which contour is directed towards the grip region of the flange. Provided in the grip region of the flange is an oval opening by means of which the overlying grip region of the cover layer can be lifted from the flange. A support element that is angled with respect to the plane of the flange is arranged in the grip region of the flange. An angled grip element or facilitating the handling of the blister pack is arranged at the edge of the flange on both sides of the hollow chamber. The base portion is so shaped that the blister packs can be nested in pairs with their undersides one inside the other, in each case the hollow chamber of one blister pack lying in the region of the grip region of the other blister pack. The blister pack is extremely handy, space-saving and stable, requires only an extremely small amount of preserving solution and enables the contact lens it contains to be removed especially easily.
摘要:
The present invention describes novel statistical copolymers and the preparation and possible uses thereof. Copolymers are described that are water-soluble and cross-linkable and that comprise the copolymerization product of a monomer mixture consisting substantially of a vinyl lactam (a) and at least one further vinyl monomer (b) of a different type selected from the group consisting of hydrophobic, hydrophilic and functional vinyl monomers, wherein the monomers are present in the copolymer in the form of statistically distributed building blocks, and, if a functional vinyl monomer is present as a building block in the copolymer, that building block is, where appropriate, modified with a reactive vinyl monomer (c), the reactive vinyl monomer (c) being linked to a building block of a functional vinyl monomer with retention of its vinylic group and with the formation of a covalent bond.
摘要:
A measured amount of a material that is crosslinkable by impingement of a suitable form of energy, especially UV light, is introduced into a two-part mould of which the cavity determines the shape of a moulding to be produced. The two mould halves are held a small distance from one another so that a thin annular gap is formed between them, which gap is in communication with the mould cavity and through which gap excess material can escape. The crosslinking is triggered by impingement of the selected form of energy, the impingement being spatially restricted to the cavity by suitable masking so that material disposed outside the mould cavity is not crosslinked. In that manner mouldings are obtained that do not require subsequent mechanical processing, and the mould is reusable. The process is especially, but not, however, exclusively, suitable for the manufacture of contact lenses.
摘要:
The present invention describes novel statistical copolymers and the preparation and possible uses thereof. Copolymers are described that are water-soluble and cross-linkable and that comprise the copolymerization product of a monomer mixture consisting substantially of a vinyl lactam (a) and at least one further vinyl monomer (b) of a different type selected from the group consisting of hydrophobic, hydrophilic and functional vinyl monomers, wherein the monomers are present in the copolymer in the form of statistically distributed building blocks, and, if a functional vinyl monomer is present as a building block in the copolymer, that building block is, where appropriate, modified with a reactive vinyl monomer (c), the reactive vinyl monomer (c) being linked to a building block of a functional vinyl monomer with retention of its vinylic group and with the formation of a covalent bond.
摘要:
Efficient and consistent processes for manufacturing moldings, especially ophthalmic lenses such as contact lenses. The processes comprises a series of improvements, including improvements in the areas of conditions for dispensing liquid prepolymer into lens molds, male and female mold mating, reusable molds, mold cleaning, lens separation from molds (demolding), lens handling, and in-line inspection. Cyclic series of processing steps are also disclosed. Additionally, an improved molding tool is disclosed, with the molding tool including a male mold housing and a female mold housing, each of which have disposed therein a plurality of mold halves.