Abstract: The production of hardboard by the wet press process is speeded up by the incorporation of finely divided fibers in an aqueous slurry of otherwise fast draining wood fibers and a thermosetting binder so that a barrier of said fine fibers is formed during hot pressing of the mat and steam pressure is built up in the mat. The high pressure permits a curing temperature of from about 300.degree. F. to about 350.degree. F. in the core of the mat and a concomitant acceleration of the cure of the binder.

Abstract: An apparatus for producing mineral fibers comprising a container having means for heating the mineral material to form a molten pool therein, a plurality of discs having a portion thereof immersed in the molten pool, and means for rotating the discs in the same angular direction at high speed. In a preferred embodiment means are provided for moving a gas such as air or steam across the edges of the rotating discs to assist in the attenuation of the fibers.

Abstract: An enclosure for a bathtub or shower having a sliding door assembly and comprising a header or supporting assembly including a front header and a side header operatively connected thereto, each header having a pair of tracks, one for each door, the tracks of the front header communicating with the respective tracks of the side header at a bevel joint, a pair of doors each having hanger assemblies mounted on their upper edge, each hanger assembly having a glider member at its end engaged in one set of said tracks, said doors being adapted to be alternatively positioned in front of the enclosure or to be slid to a storage position along a side wall of the enclosure.

Abstract: A wet-felted mat of wood fibers is acetylated by coating the mat with a quantity of acetic anhydride ranging from 5 to 70% by volume of the mat and heating the mat at a temperature of from 150.degree. to 300.degree. F. while confining substantially all of the acetic anhydride within the mat for about 20 to 120 minutes. The acetylated mat is pressed into hardboard which may be bent into a variety of loops, spirals, helices, and other curvilinear shapes to make articles of furniture, protective packaging products and the like.

Abstract: A water-based stain having a working time of from about 1 to about 3 minutes and a tack-free drying time of from about 10 to about 15 minutes at 160.degree. F. comprises an acrylic latex, a drying oil, ester gum, a glycol, a hydrocarbonaceous solvent, and pigment.

Abstract: An apparatus for the production of mineral fiber or wool felts, blankets or batts having uniform thickness and density, comprising means for fiberizing the mineral composition, a housing defining a chamber into which the fibers are introduced, a foraminous belt upon which the fibers are deposited, a rotating brush for sweeping or throwing back excess fibers, thereby leaving a uniform layer of uncompressed fibers on the felt, and a roller for compressing the layer of fibers into a felt. The rotary brush removes the excess fibers and cooperates to provide a felt which is of uniform density and thickness.

Abstract: A flexible door or curtain support comprising an elongate member having a track for supporting the door or curtain, and apparatus for providing tension between the elongate member and a supporting wall comprising a pad or wall member for engaging the wall, a pressure plate engaging the end of the elongate member, and wedge or a cam mechanism cooperating with the pressure plate and the pad or wall member, and a mechanism for moving the wedge member to provide longitudinal tension between the elongate member and the wall.

Abstract: A building board comprises a core 31 of set cementitious material, such as gypsum, faced on at least one side by a fabric or web 33 of mineral fibres embedded in the face of the core and a continuous film 32 of the cementitious material having a higher density and lower porosity than the core extending over the outer face of the fabric. The film may have a smooth surface or a desired textured or figured surface. The preferred fabric or web 33 is a non-woven glass fibre tissue and it is preferred that a continuous film 32 of gypsum at the surface should not exceed 2 mm in thickness. The board is made by bringing the fabric or web into contact with the respective face of a layer of an aqueous slurry of gypsum plaster or other cementitious material, and vibrating the layer of slurry in contact with the fabric or web until slurry penetrates the web and the latter is completely embedded.

Abstract: A pivotal door for an entrance or passageway, and particularly for shower or bathtub enclosures, comprising a plurality of frame members, a panel mounted in said frame members, a channel provided in both top and bottom frame members, and a pair of pivot members each having one end adjustably retained within one of the channels, and the other end engaged in a socket provided in the shower enclosure frame, each pivot member being arranged to be affixed at any of a plurality of positions on the channel to enable the door to be utilized with enclosures having entrances of different widths.

Abstract: A composite paper particularly adapted for use as cover sheets in the production of gypsum wallboard, the paper being sufficiently porous to permit better drainage and more rapid drying in the production of the paper, and when applied to the surfaces of a gypsum slurry for forming wallboard, permits less heat to be utilized in the wallboard conversion, thereby saving energy in the board production required for drying the board. The paper comprises in weight percent:(A) fibers in an amount of from about 65% to about 90% and having a fiber freeness of from about 350 to 550 ml. Canadian Standard Freeness,(B) a mineral filler in an amount from about 10% to about 35%,(C) a binder in an amount from about 1% to about 31/2%,(D) a flocculant in an amount of from about 2 to about 4 lb./ton, and(E) a sizing agent in an effective amount to prevent water penetration.

Abstract: Wallboard joint tape is coated with joint compound as the tape is drawn through a container of the compound and made to pass through a tabbed slot in or associated with the container. The tabs urge the coated tape away from the edge of the slot which would otherwise wipe off the coating when the tape is drawn through the slot from a position higher than the slot.

Abstract: A method for making a decorated, water-resistant, rigid panel comprising supplying a cured, pre-coated rigid panel having a clear, water-resistant polymeric coating on one surface of the panel and a printed sheet having a design, picture or other form of decoration on one surface thereof, said decoration being formed by a sublimable coloring agent. The rigid panel and the printed sheet are originally maintained at room or ambient temperature. The coated surface of the rigid panel and the decorated surface of the printed sheet are brought into physical contact, and their surfaces are maintained in contact for a brief period of time by applying light pressure thereto. While the surfaces are maintained in contact, heat is applied thereto for a short period of time to sublime the coloring agent and cause it to be transferred to and penetrate into the polymeric coating on the surface of the rigid panel.

Abstract: Air heated outside the calcining zone of a shaft kiln is passed through raw material in a hopper mounted above the kiln in order to preheat the raw material. In one embodiment the preheating air is heated by an excess air burner which communicates with the hopper. In another embodiment, the hot calcined material is cooled by forcing cool air through it and the heated air is utilized as preheating air by directing it through a by-pass conduit which connects the cooling zone of the kiln with an extension of the hopper. In neither embodiment does the preheating air constitute combustion supporting air.

Abstract: A method of surface treatment for plaster articles to improve wear and water resistance is disclosed. The method includes the step of forming the article, allowing the article to set, drying to remove excess water, applying a coat of substantially molten Candelilla wax onto an exterior surface of said article, maintaining said wax at a temperature of no less than 155.degree. F. (68.degree. C.) for sufficient period of time to allow said wax to substantially fill exterior pores and irregularities, and cooling said article to solidify the wax. Also disclosed is a wear resistant and water repellent plaster article comprising a formed plaster article having an exterior surface portion thereof coated with a thin layer of Candelilla wax, said coated surface portion providing a substantially water impregnable barrier and providing enhanced wear resistance.

Abstract: A rapid reaction of high alumina cement, gypsum, lime and water produces cementitious compositions in which the only significant factor contributing to strength during the very early stages of hydration (i.e., a few minutes to a few hours) is the formation of an amount of ettringite equal to from about 40% to about 60% of the weight the paste of water, the high alumina cement, the gypsum source, and the lime source. A substantially impermeable concrete having a 4-hour compressive strength of about 8000 p.s.i. may be produced from the cement powder of this invention.

Abstract: Blocks or panels 10, more especially of porous or cellular structure, are faced with a fabric or web inorganic fibres, preferably in the form of glass fibre tissue, bonded to the block or panel by a composition 14 of thermosetting condensation polymer and gypsum, preferably in a ratio between 1:1.6 and 1:4.0. The amount of the composition is preferably such as to provide a film of minimal thickness over the surface of the fabric or web, corresponding to a glass: resin plus gypsum proportion of 8 to 25%. Such coatings when applied to foamed plastics, chip-board or glass fibre panels provide boards suitable for ceilings or partitions and having ample strength and flame resistance. The blocks or panels may be made continuously by applying fibrous tissues, impregnated with a fluid mixture of plaster and resin by roller spreaders, to the face of panel elements supported between release sheets, for example of polypropylene. Pressure may be applied and maintained, if desired, until the fluid mixture has set.

Abstract: A decorative soffit system for mounting on the bottom of vertically disposed ceiling tile to enclose a projection depending from the ceiling as disclosed. The soffit system having a U-shaped channel member adapted to rest on an inverted-T runner and said U-shaped channel member having a resilient spacer therein to hold a vertically disposed ceiling tile against one side thereof.

Abstract: A combination of a hydroxy polycarboxylic acid and a starch hydrolyzate improves the compressive strength at early and late ages of a calcium sulfoaluminate cement.

Abstract: A combination of a hydroxy polycarboxylic acid and sucrose improves the water-demand, setting, and compressive strength properties of a calcium sulfoaluminate cement to a greater degree than would be the case if the hypothetical cumulative effect of two admixtures were operative.

Abstract: A fire resistant floor and ceiling assembly comprising in combination; a plywood layer; a gypsum floor underlayment extending adjacent below said plywood layer; a series of steel joists located below said underlayment and supporting the plywood and underlayment; a space-apart multiplicity of self-drilling self-tapping screws extending downwardly through the plywood and underlayment, and engaging said steel joists thereby attaching the plywood and underlayment to the steel joists, said screws having upper threads and lower threads with an interrupting non-threaded mid-portion therebetween, the non-threaded mid-portion extending a distance substantially the same as the thickness of said plywood layer; and, at least one layer of third generation fire resistant gypsum board connected to, and supported below, said steel joists by connecting means; whereby said assembly contains no combustibles in the plenum between said underlayment and fire resistant gypsum board, and whereby said assembly attains at least a one