Abstract: This invention relates to recently developed systems which produced bleached recycled fibers from high lignin content recovered paper materials such as old corrugated containers and old newspapers. Such systems of this type, generally, use chemical digestion (e.g., the kraft process) to reduce the lignin content prior to bleaching. Since recovered paper materials normally have high levels of aluminum, which are derived from the paper sizing and pH control chemical, aluminum sulfate; and since soluble aluminum causes scaling of evaporators in the kraft digestion-chemical recovery cycle, there is a need for a means to remove soluble aluminum from the recovered paper materials prior to digestion.

Abstract: This invention relates to paperboard packages or cartons suitable for distributing, marketing and heating prepared food products. Such structures of this type, generally, include a coating which is mass stable below 400.degree. F., has chloroform-soluble extractives not exceeding 0.5 mg/in..sup.2 of a food contact surface when exposed to a food simulating solvent of 150.degree. F. for two hours and is flexible enough to withstand conventional scoring in a cross-direction with a 2 point male rule and a 0.062 inch channel while sustaining a crack length ratio of no greater than 0.1.

Abstract: This invention relates to a process of making paperboard materials for carrying static cling vinyl products for transport to end users. Such structures of this type, generally, provide good adhesion for the static cling vinyl product, but allow the vinyl product to be peeled off easily.

Abstract: This invention relates to a method for reducing off-taste and/or odor from hygienic paper packages (such as food and beverage packaging) by heating and steam stripping the surface of the paper web. Such methods of this type, generally, remove undesirable compounds that create off-taste and/or odor from the paper package in a simple, cost-effective manner.

Abstract: Subjective paper characteristics such as visual appearance and print quality are often objectively related to certain scales of surface roughness. Three dimensional topographic surface data is obtained from a paper sample secured by vacuum to a flat, porous plate for translational movement in a grid pattern beneath a vertically compliant stylus that is resiliently suspended beneath a rigid, overhead support beam. Such surface data is mathematically filtered by a linear convolution technique or the distinctly alternative circular convolution technique to segregate the raw data characteristics of component surfaces that contain only certain frequencies of roughness. The root-mean-square variations of such component surfaces is then used to objectively characterize respective surface characteristics.

Abstract: This invention relates to the measurement and control of consistency in an aqueous flow stream, as it leaves a stage (i.e. Bleaching Stage) of the papermaking process. More particularly, the present invention relates to the measurement used for control of wood fiber and suspended solids in a papermaking pulp stock flow stream.

Abstract: This invention relates to a retrofit apparatus utilized in Ultraviolet (UV) light sterilization equipment for paperboard packaging filling machines. Such structures of this type, generally, allow conventional paperboard packaging filling machines to be economically converted to include an ultraviolet light sterilization retrofit assembly wherein microbiological spoilage of the food product contained within the paperboard packaging can be significantly reduced.

Abstract: This invention relates to headboxes which are used in papermaking machines. The inventive structure employs the use of a plurality of venturis located between the headbox chamber and the slice. Each venturi is located adjacent to a pulp conduit spaced transversely across the headbox chamber.

Abstract: This invention relates to a hexagonal paperboard carton that is tapered with an automatic bottom. Such structures of this type, generally, provide a peeling feature that allows the consumer to remove the carton from the product in a continual, spiral strip.

Abstract: This invention relates to a method for producing packaging materials containing reclaimed/recycled fiber by chemically hydrolyzing the fiber, treating the fiber at elevated temperature greater than 100.degree. C., adding a reduced sulfur agent to the fiber to reduce the sulfur content of the fiber by forming insoluble heavy metal sulfide compounds which precipitate from the hydrolyzed fiber, oxidizing and then washing the fiber to produce a paper pulp. Such methods of this type, generally, produce reclaimed/recycled fiber that is sufficiently hygienic for food grade and medical device packaging applications.

Abstract: This invention relates to improvements in the top-to-bottom compressive strength of corrugated fiber containers through the use of a minimum amount of extra fiber. Such structures of this type, generally, employ strip and patch laminations which provide minimal additional fiber and maximal reinforcement in the areas of the corrugated container panels that are under the highest compressive stresses when the containers are subjected to compressive loads.

Abstract: This invention relates to sleeves or belts which are used in paper machines. Such structures of this type, generally, are reinforced through the use of reinforcing fibers which are oriented at an angle turned 45.degree. from the straight machine direction orientation. This arrangement aligns the individual reinforcing strands in the direction of the principal tensile stresses that exist within the sleeve or belt structure as the sleeve or belt is being rotated in the paper machine.

Abstract: Lids and/or closures applied to cartons which are used for distributing, marketing and heating small portions of prepared food are fabricated with a paperboard structural substrate coated with a heat activated (or sealable) coating of water soluble acrylic emulsion that is applied by means of a press in conjunction with a printing operation or, alternatively, by a coating operation separate from the printing operation. Other critical coating characteristics are that the acrylic emulsion coating is heat sealable to itself, to polymers such as polyethylene terephthalate and directly to unprimed paperboard, with or without a clay coating, and can be tack bonded at temperatures of 250.degree. F. or greater. Additionally, so as to avoid food contamination from the coating, the coating is mass stable below 400.degree. F. and have chloroform-soluble extractives not exceeding 0.5 mg/in.sup.2 of a food contact surface when exposed to a food simulating solvent, (for example, N-Heptane) at 150.degree. F. for two hours.

Abstract: This invention relates to paperboard food packages. Such structures of this type, generally, have lids which can be sealed to the food package which utilizes press-applied coatings as a sealing medium.

Abstract: The present invention relates to a method and apparatus for producing paperboard packaging blanks (trays, lids, cartons, or combinations) in which the application of the barrier coating is combined with the printing of the sales graphics in a single-pass operation which eliminates the need for a separate off-line coating operation.

Abstract: Folded paperboard food cartons having a barrier polymer coating only on the interior surface and sales graphics on a substantially unplasticized clay coated exterior surface are heat sealed at contiguous areas of overlapping flaps wherein the polymer coated interior surface is in direct contact with a small portion of the clay coated exterior surface or where it is desired to secure together two portions of the clay coated exterior surface. In such heat sealing areas, small and accurately located exterior clay coated carton surface areas are printed with a patterned solvent based polymer material that is precisely applied to such areas by a printing press.

Abstract: This invention relates to an apparatus and method for measuring the peel strength of a paper joint which is adhesively bonded. Such structures of this type, generally, allow the peel strength of the adhesively bonded joint to be accurately and repeatably measured in an inexpensive manner.

Abstract: A low contaminant level is maintained in a high flow rate paper machine coating fluid circulation system by shunting a significant minority portion of the total flow through a full flow, atmospherically open, self-cleaning screen having a fine mesh screen cloth. Accept flow from the open screen is directed to the flow inlet of an entrained air purging apparatus for dispersing consolidated particulates of excessive size. Flow from the particulate disbursing apparatus is thereafter pumped through an enclosed pressure screen of moderate screen mesh.

Abstract: A composite food packaging article having internal partitioning walls and corresponding method of manufacture is constructed from flat, machine formed paperboard. A pair of die cut and folded paperboard blanks are inserted within the opposing cavities of a blow mold. A hot-flow parison between the cavities expands to structurally unitize the folded paper blank into a fluid impermeable tray vessel.