The invention is related to method for developing and producing contact lenses with a target lubricity profile as characterized by having a velocity-weighted average coefficient of friction, as determined by use of a lubricity test of the invention.

A method of 4D printing a hydrogel composite structure comprises depositing a first layer of filaments on a substrate in a first predetermined arrangement, where each filament comprises a hydrogel matrix and a plurality of anisotropic filler particles embedded therein. A second layer of the filaments is deposited in a second predetermined arrangement on the first layer. The filaments from the second layer contact the filaments from the first layer at a number of contact regions. The first layer and the second layer are hydrated, and the filaments of the first and second layers swell in size while remaining in contact at the contact regions. Thus, a curved three-dimensional hydrogel composite structure is formed.

The present invention includes methods for forming an object in a volume including a photohardenable composition described herein that includes a photohardenable resin component and a photoswitchable photoinitiator comprising a P-type photochromic molecule. The present invention also includes photoswitchable photoinitiators comprising a P-type photochromic molecule, preferably comprising a P-type diarylethene molecule, and photohardenable compositions and methods including such photoswitchable photoinitiators.

An alginate-polyacrylamide IPN hydrogel formulation for 3D printing using a dual syringe system where the components that initiate polymerization of each network remain separated until printing. The dual syringe system may use a single motor and mixing head to combine both parts of the hydrogel formulation for controlled polymerization of the material. The elastic and time-dependent viscoelastic properties (stress relaxation) are tuned to match mammalian tissues by changing the crosslink density and monomer concentration. The fracture energy of the material may be increased by soaking in a calcium chloride solution. The resulting IPN polymer material may find application in soft tissue medical simulation devices, particularly because the mechanical properties may be tuned to mimic the elastic and viscoelastic properties of muscle tissue and may be 3D printed in the shape of anatomical parts.

A composition comprising a plurality of cell aggregates for use in the production of engineered organotypic tissue by organ printing. A method of making a plurality of cell aggregates comprises centrifuging a cell suspension to form a pellet, extruding the pellet through an orifice, and cutting the extruded pellet into pieces. Apparatus for making cell aggregates comprises an extrusion system and a cutting system. In a method of organ printing, a plurality of cell aggregates are embedded in a polymeric or gel matrix and allowed to fuse to form a desired three-dimensional tissue structure. An intermediate product comprises at least one layer of matrix and a plurality of cell aggregates embedded therein in a predetermined pattern. Modeling methods predict the structural evolution of fusing cell aggregates for combinations of cell type, matrix, and embedding patterns to enable selection of organ printing processes parameters for use in producing an engineered tissue having a desired three-dimensional structure.

The invention relates to a process for the production of mould-foamed poly(meth)acrylimide (P(M)I) cores, in particular of polymethacrylimide (PMI) cores, which can be used by way of example in automobile construction or aircraft construction. A feature of this process is that polymer granules or polymer powder preheated under pressure are moreover charged under pressure to a compression mould where they are foamed with depressurization. In particular, a feature of the process is that it optionally uses a preferably two-shell compression mould for the heating and also for the cooling of the granules and, respectively, the rigid foam core formed therefrom.

The present invention generally relates to compositions comprising a binder and a metal powder, and associated methods. Some compositions provided include a polymer and a metal powder. Some compositions provided include a binder formulation and a metal powder. The binder formulation generally includes a first liquid and a polymer. The binder formulation may be a solution. The polymer may include a nitrogen-containing repeat unit. The metal powder may include a noble metal. Some methods provided include combining a metal powder with a binder formulation. Methods provided include but are not limited to additive manufacturing processes and injection molding processes.

Parallel surfaces on two substrates are established with specific distances of separation, typically within a 10-micron tolerance. In general, one surface is a surface of a transparent membrane or hard window. On one embodiment, the gap defined by the distance of the transparent membrane or hard window and the other surface used to precisely control the dimensions of layers in projection micro stereolithography, however the methods for establishing the relative positions of two surfaces can be adapted to other applications.

A three-dimensional shaped article manufacturing apparatus is an apparatus for manufacturing a three-dimensional shaped article by laminating layers formed by discharging and curing inks including a curable resin. The apparatus comprises: a first discharge unit configured to discharge a substantive section-forming ink to a region that forms the three-dimensional shaped article; a second discharge unit configured to discharge a sacrificial layer-forming ink for forming a sacrificial layer to a region that is adjacent to a region that forms an outermost layer of the three-dimensional shaped article and on a surface side of the outermost layer; and a curing unit configured to cure the substantive section-forming ink and the sacrificial layer-forming ink. A viscoelasticity of the sacrificial layer-forming ink during curing of the substantive section-forming ink being not less than a viscoelasticity of the substantive section-forming ink during curing of the substantive section-forming ink.

The present invention aims to provide a supporting material for supporting the shape of a photofabrication model on photofabrication in ink-jet three dimensional printing method in which the photocured product is excellent in solubility in water and is easy to remove after photofabrication, and the like. A modeling material for forming a photofabrication model in ink-jet three dimensional printing method containing a curable resin component with a weighted average of SP value of 9.0 to 10.3; and a supporting material for supporting the shape of a photofabrication model on photofabrication in ink-jet three dimensional printing method containing a water-soluble monofunctional ethylenically unsaturated monomer (F), polyoxypropylene glycol with a number average molecular weight of 100 to 5,000 and/or water (G), and a photopolymerization initiator (D).