Embodiments of the disclosure are directed towards a composite stiffener that is incorporated into panelized products to create stronger bonding, greater adhesion between laminated layers and less warping sandwich panels. In addition, the resulting products incorporating composite stiffeners can be lightweight, yet stronger than other lightweight panels.

The present invention relates to shaker doors with solid cores and methods for making the same. The shaker doors contain different core materials at the recessed panel than the raise peripheral region to provide dimensional stability and reduced distortion when the doors are exposed to high humidity. The devices and methods also provide for easy assembly of solid core shaker doors, including fire rated doors.

A reinforcing structure for a door includes a first region constructed from a first grade of corrugated paperboard and second and third regions constructed from a second grade of corrugated paperboard. The first region may be expandable and the second and third regions may be non-expandable. A method for installing the reinforcing structure in a door having a frame and two opposed skins with recessed areas includes installing the reinforcing structure on the surfaces of the recessed areas between the skins.

The present invention relates to a double backbone core for automated hollow door manufacture and a door comprising same. The double backbone core comprises an expandable core component comprising two backbones with relatively smaller cells running parallel to one another along the length dimension of the door, wherein the core is formed from a plurality of interconnected strips.

The present invention relates to shaker doors with solid cores and methods for making the same. The shaker doors contain different core materials at the recessed panel than the raise peripheral region to provide dimensional stability and reduced distortion when the doors are exposed to high humidity. The devices and methods also provide for easy assembly of solid core shaker doors, including fire rated doors.

A method for manufacturing a three-dimensionally deformed plate made of a wood fiber material comprises providing a prefabricated, flat wood fiber material plate as the original plate, preheating the original plate in sections, wetting the preheated section of the original plate with an atomized liquid mixture of water and a separating agent, introducing a section of the original plate that is preheated and wetted with a liquid mixture of water and a separating agent between two rollers of a molding station, wherein the rollers respectively provide a corrugated profile in the peripheral direction of the external surface, such that the original plate is being deformed in sections into a plate with a wave shape, wherein rollers are being used, the respective profiling of which has half-waves which follow one another in the peripheral direction and which at least partially have a different extension in the peripheral direction.

A door includes a first skin, a second skin, and a core. The core is disposed between the first skin and the second skin in a thickness direction of the door and spans between the first and second skins. The core includes a corrugated medium that is fluted with fluting running back and forth in the thickness direction between the first skin and the second skin as the corrugated medium spans between the first and second skins. The door also includes a compressed section where at least one of the first skin and the second skin is compressed into the core toward the other of the first skin and the second skin in the thickness direction.

This invention relates to a core for hollow door manufacture comprising a method whereby the mechanical arrangement of the core glue applicators produces multi sized closed cell filler material once severed and expanded wherein a combination of both contracting and expanding cells presents as a centrally aligned column of contracting cells while other cells expand utilizing adhesively affixed non rigid flexible single face corrugated material.

A core layer suitable for a multilayer composite including at least one surface layer and one core layer, the surface layer arranged to at least partially cover the core layer and be fixedly connected thereto, wherein the core layer has elements composed of wood, which elements have plate-like regions arranged in zig-zag-shaped fashion, wherein a plate-like zig region of an element with an adjoining plate-like zag region of the element form a common edge between them, in such a way that the wood element of zig-zag-shaped form is formed, wherein elements of zig-zag-shaped form are arranged in the core layer such that two such edges of two different elements cross one another at a non-zero angle, and wherein the two elements are fixedly connected to one another at the crossing point. In one embodiment, a wood element of zig-zag-shaped form may be adhesively bonded to a planar wood element.

A fire rated door includes a core, a first decorative panel and a second decorative panel. The core includes: (a) a gypsum-based fire resistant center panel having a bottom, a top, a first side, a second side, a first end and a second end, wherein the gypsum-based fire resistant center panel is made of a first gypsum-based fire resistant material, and (b) an extruded gypsum-based fire resistant border attached to the first side, the second side, the first end and the second end of the gypsum-based fire resistant center panel, wherein the extruded gypsum-based fire resistant border is made of a second gypsum-based fire resistant material having a higher density than the first gypsum-based fire resistant material. The first decorative panel is attached to the top of the gypsum-based fire resistant center panel and the extruded gypsum-based fire resistant border. The second decorative panel is attached to the bottom of the gypsum-based fire resistant center panel and the extruded gypsum-based fire resistant border.