The invention relates to a process for the production of at least two-layer thermoplastic sheets via thermal welding of at least one thinner thermoplastic sheet with density (D1) and of at least one second thinner thermoplastic sheet with density (D2), where the density (D1) of the first thinner thermoplastic sheet is smaller than the density (D2) of the second thinner thermoplastic sheet. The process introduces at least one first heating element and at least one second heating element along mutually offset planes between the two thinner thermoplastic sheets, where the surfaces of the thinner thermoplastic sheets do not touch the surfaces of the heating elements. The first heating element transfers a quantity of energy (E1) to the surface of the first thinner thermoplastic sheet, and the second heating element transfers a quantity of energy (E2) to the surface of the second thinner thermoplastic sheet, where the quantity of energy (E1) is smaller than the quantity of energy (E2).

A method for welding at least two parts including a thermoplastic material and having respective surfaces to be welded, including: inserting an insert between the surfaces to be welded of the two parts; generating heat via the insert; wherein the insert moves in relation to the parts to be welded in a welding direction. Also, an installation adapted for implementation of this method.

A method for welding at least two parts including a thermoplastic material and having respective surfaces to be welded, including: inserting an insert between the surfaces to be welded of the two parts; generating heat via the insert; wherein the insert moves in relation to the parts to be welded in a welding direction. Also, an installation adapted for implementation of this method.

A method or apparatus for three-dimensionally printing. The method may comprise causing a phase change in a region of the first material by applying focused energy to the region using a focused energy source, and displacing the first material with a second material. The apparatus may comprise a container configured to hold a first material, a focused energy source configured to cause a phase change in a region of the first material by applying focused energy to the region, and an injector configured to displace the first material with a second material. The first material may comprise a yield stress material, which is a material exhibiting Herschel-Bulkley behavior. The yield stress material may comprise a soft granular gel. The second material may comprise one or more cells.

An exemplary embodiment of the present disclosure provides a fire resistant material and methods of making same, the fire resistant material comprising a material incorporating a mixture comprising carbon nanotubes, nanoclay, and a dispersing agent.

Compounds and compositions are provided which are useful in additive printing, particularly additive printing techniques such as stereolithography (SLA), wherein a composition of one or more photocurable compounds, such as a compound with multiple ethylenically unsaturated groups and a compound with multiple thiol groups, is photopolymerized, optionally in the presence of two or more thermocurable compounds which are reactive with one another and are subjected to thermopolymerization, to form a manufactured article in solid form.

Parts made by additive manufacturing are often structural in nature, rather than having functional properties conveyed by a polymer or other component present therein. Printed parts having piezoelectric properties may be formed using compositions comprising a plurality of piezoelectric particles dispersed in at least a portion of a polymer matrix comprising first polymer material and a sacrificial material, the sacrificial material being removable from the polymer matrix to define a plurality of pores in the polymer matrix. The piezoelectric particles may remain substantially non-agglomerated when combined with the polymer matrix. The sacrificial material may comprise a second polymer material. The compositions may define a composite having a form factor such as a composite filament, a composite pellet, a composite powder, or a composite paste. Additive manufacturing processes may comprise forming a printed part by depositing the compositions layer-by-layer and introducing porosity therein.

A resin frame includes frame members combined into a frame shape that includes a corner portion, and a joint portion joining a pair of the frame members which are adjacent to each other at the corner portion. The joint portion includes an entire-surface welded portion, in which end surfaces of the pair of the frame members are welded to each other over an entire surface in a thickness direction of a plate portion of the frame members, and a partial welded portion, in which the end surfaces of the pair of the frame members are welded to each other on one side of the entire surface in the thickness direction while another side of the entire surface in the thickness direction is not welded. The entire-surface welded portion and the partial welded portion are present at different portions on an outer periphery of the joint portion.

A resin frame includes frame members combined into a frame shape that includes a corner portion, and a joint portion joining a pair of the frame members which are adjacent to each other at the corner portion. The joint portion includes an entire-surface welded portion, in which end surfaces of the pair of the frame members are welded to each other over an entire surface in a thickness direction of a plate portion of the frame members, and a partial welded portion, in which the end surfaces of the pair of the frame members are welded to each other on one side of the entire surface in the thickness direction while another side of the entire surface in the thickness direction is not welded. The entire-surface welded portion and the partial welded portion are present at different portions on an outer periphery of the joint portion.

A core-sheath filament having a non-tacky sheath and a hot-melt processable adhesive core, the sheath exhibiting a melt flow index of less than 15 grams per 10 minutes, is provided. Methods of making the core-sheath filament and methods of using the core-sheath filament to print a hot-melt processable adhesive onto a primer-treated substrate surface to provide a structural bond are described.