Abstract: Plies that are formed by respective formers are couched together in a sheet forming device, specifically a machine for the production of a multi-ply fiber web, particularly a paper or cardboard web, or a packaging paper web. At least one of the formers for forming a multi-ply web includes a multi-layer headbox, to which at least two different stocks, or stock partial streams of different composition for different plies are furnished.

Abstract: Disclosed is a multi-layer paper suitable as a material for preparing heat-sensitive stencil printing masters. The multi-layer paper is produced by combining a plurality of thin paper layers by paper making. The multi-layer paper has a peel strength of 10 N/m or less and may be delaminated into at least two tissue sheets.

Abstract: A board machine and method for making a multilayer cardboard web, in which a first layer of the web having a printable surface is formed in a first forming unit and carried on an extended forming wire thereof through a couching unit where the first layer is couched with one or more additional layers, the multilayer web then being carried on the extended wire to a pick-up point. An upper press felt of a double-felted press picks up the web at the pick-up point such that the printable surface faces downward and contacts the lower press felt through the nip of the press. The lower felt is smoother than the upper felt, and the lower felt contacts the lower press roll for a minimum sector angle beyond an exit of the nip to ensure that the web follows the lower felt.

Abstract: A process for increasing the tactile properties of a base web without adversely affecting the strength of the web is disclosed. In general, the process includes the steps of placing a base web in between a first moving conveyor and a second moving conveyor. The conveyors are then wrapped around a shear inducing roll which creates shear forces that act upon the base web. The shear forces disrupt the web increasing the softness and decreasing the stiffness of the web. The shear inducing roll typically has a relatively small diameter. In some applications, more than one shear inducing roll may be incorporated into the system.

Abstract: A latex as a binder for nonwoven applications to form a permeable sublayer of personal hygiene articles. The latex is prepared by a process including the steps of (1) polymerizing a monomer mixture comprising styrene, itaconic acid, surfactant and water soluble free radical initiator to form a seed; (2) sequentially adding equal increments of a monomer mixture of styrene, butadiene and acrylic acid to the seed under emulsion polymerization conditions to form a styrene-butadiene-acrylic acid copolymer; and then (3) neutralizing the styrene-butadiene-acrylic acid copolymer to a pH of about 4.5 to 7 to form the latex.

Abstract: Chemical additives can be adsorbed on cellulosic papermaking fibers at high levels with a minimal amount of unadsorbed chemical additives present in the papermaking process water. A method includes treating a fiber slurry with an excess of the chemical additive, allowing sufficient residence time for adsorption to occur, filtering the slurry to remove unadsorbed chemical additives, and redispersing the filtered pulp with fresh water. Filtrate from the thickening process contains unadsorbed chemical additive and it is not sent forward in the process with the chemically treated fibers. The method can be employed to make improved paper products.

Abstract: A product and process of making an absorbent paper article such as paper products, towels, napkins and the like is disclosed. In the invention, one may supply a single furnish, or slurry, of cellulose fibers. Then, it is possible to separate or fractionate the slurry into at least two portions based upon fiber length in the slurry. Fines are employed in the process of manufacturing the products, and fines are specifically incorporated into an inner layer of the final paper products. Fines, short fibers, and/or fibrils are used in the process so they may contribute in a positive manner to the final paper product, rather than acting in a negative manner as a chemical “sponge” or waste material. This use of fines in the inner layers of the product reduces the manufacturing cost and waste produced in the process. A soft paper product with good strength characteristics results from the process.

Abstract: A method for making a paper sheet comprising at least one region which is thinner than the rest of the sheet. According to the method, a first paper layer (3) is formed on a wire in a first wet end of a paper-making machine, a second paper layer (5) is formed on a wire in a second wet end of the paper-making machine, one of the two paper layers has a number of localized tinner regions (8) so that the thickness (e2) of said paper layers in said regions is up to 50% less than the thickness (et) of the rest of the sheet, and the two layers are joined together and dried. The resulting paper may be used in banknotes or checks.

Abstract: An embossed multiple ply paper product and process for producing such product displaying aesthetically pleasing decorative attributes and exhibiting functional characteristics of softness, absorbency, and drape. The decorative attributes comprise embossed patterns of indicia displaying a high quality cloth-like appearance for a softer, more quilted look. The plies are joined in a face-to-face arrangement by selective bonds which are limited to the indicia, in order to produce more permanent decorative figures that inhibit dissipation caused by compressive forces, humidity, absorption, etc.

Abstract: Method of producing a paper having a three-dimensional pattern of alternating raised and recessed portions which is given the paper in connection with impulse drying. The paper web has a varying material composition as seen in its thickness direction, so that it at least in an outer layer contains an amount of a material that softens, melts or hardens in the temperature interval 100-400° C. or in some other way contributes in stabilizing the pattern structure that has been given the paper. It is further referred to an impulse-dried paper produced according to the method.

Abstract: Method of producing a paper having a three-dimensional pattern of alternating raised and recessed portions which has been provided in connection with impulse drying, at which the wet paper web (10) is passed through at least one press nip (12) comprising a rotatable roll (13) which is heated and that the paper web during the passage through the press nip is given a three-dimensional pattern of alternating raised and recessed portions either by means of a pattern wire, band or belt and/or by a pattern on the heated roll (13) and where the paper web (10) after said press nip (12) is led around an essential part of the periphery of the heated roll (13) in order to provide an additional drying of the paper web while this is still in contact with said three-dimensional pattern.

Abstract: A machine for the manufacture of a fibrous web includes a back liner former, a top liner former and at least one middle layer former. The back liner former is configured for producing a back liner, comprised of a fibrous web, with one side of the back liner having a higher fines content. The top liner former is configured for producing a top liner, comprised of a fibrous web, with one side of the top liner having a higher fines content. The middle layer formers, being configured for producing at least one middle layer, comprised of a fibrous web, with one side of the middle layer having a higher fines content, the other side of the middle layer having a lower fines content. Each middle layer former and the top former having couch rolls that define an associated couching zone; wherein the back liner former and each middle layer former are configured such that the side of the higher fines content of the back liner contacts the lower fines content side of the middle layer.

Abstract: Process and apparatus for producing a fibrous material web from a fibrous material suspension. The process includes conveying the fibrous material suspension between two endless, continuously revolving porous belts positioned to form a twin wire zone, removing a part of the suspension fluid through the porous belts so that the fibrous material web begins forming between the belts, guiding the two endless belts and the material web being formed therebetween through uniform pressure drainage elements, and removing additional suspension fluid with the uniform pressure drainage elements. The process further includes supplying an additive though at least one of the belts to the forming fibrous material web in a vicinity of the uniform pressure drainage, and one of controlling and regulating the supply of the additive to provide a particular ratio between quality levels of a top side of the forming web and a web underside of the forming web.

Abstract: The invention relates to embossing multi-ply paper products, for example, paper towels, tissue and napkins, in which an improved embossing arrangement is used which is particularly suitable for paper products which have been processed so as to impart undulations whose axes extend in a principal undulatory direction, typically in the machine direction. The absorbent sheet typically further includes undulations which extend in the cross (transverse direction) of the web such that the absorbent sheet has a biaxially undulatory structure. The undulations may be formed by the use of an undulatory creping blade. Defined parameters accommodate: the distance at which the undulations are spaced, the total surface area of the design (embossing) elements, the width and length of the embossing elements and the aspect ratio of the elements, as well as the angular orientation of the embossing elements with respect to the undulations.

Abstract: A multi-ply web forming method and apparatus are disclosed for forming a top ply onto a base ply. A fiber suspension jet is by means of a secondary headbox (21; 21′, 26) delivered into a twin-wire roll nip created by two tensioned wires (16, 22; 16′, 22′; 22, 27) one of which (16; 16′, 22) carries the moist base ply.

Abstract: A toilet tissue product may include a first cellulosic ply and a second cellulosic ply. Desirably, the first cellulosic ply further includes a single layer and the second cellulosic ply further includes a single layer. At least one ply may have a region that prevents fluid from striking through the tissue product.

Abstract: An embossed multiple ply paper product having a nested latticework embossment pattern providing a cloth-like, quilted appearance and a process for embossing and bonding such multiple ply paper product. The multiple ply paper product comprises a latticework of cells composed of n rows of embossment elements nested within an interfacing latticework of cells composed of n+1 rows of embossment elements.

Abstract: Provided is a multi-layered water-decomposable fibrous sheet with a plurality of layers each having a different fibrous constitution being integrated, including a top layer on a top surface and a back layer on a back surface. The top layer includes fibrillated rayon of at least 3% by mass of all fibers constituting the top layer. The fibrillated rayon has a degree of beating of at most 700 cc, and has primary fibers of a predetermined fiber length and microfibers extending from the primary fibers. The microfibers are entangled with and/or hydrogen-bonded to at least either of other microfibers and other fibers. The back layer includes fibers containing no fibrillated rayon, the fibers entangled with and/or hydrogen-bonded to each other, or the back layer includes the fibrillated rayon in an amount smaller than that in the top layer. The microfibers of the fibrillated rayon are entangled with and/or hydrogen-bonded to at least either of other microfibers and other fibers.

Abstract: A multi-ply tissue contains an internal indicia, such as a printed pattern applied to the center ply, which is visible through the outer plies of the tissue and which indicates the presence of some unique ingredients within the tissue product.

Abstract: The invention relates to hydrophilic, humectant, soft, pliant, single-ply or multi-ply absorbent papers in the form of a towel. These humectant paper products are formed by supplying a furnish to headbox comprising: Cellulosic papermaking fiber consisting essentially of recycle fiber, hardwood fiber, softwood fiber, and mixtures thereof; and optionally up to 50% synthetic fibers and a softener which has a melting range of about 0°-40° C. wherein the softener comprises an imidazoline moiety formulated in organic compounds selected from the group consisting of alkoxylated aliphatic polyols, alkoxylated aliphatic diols, aliphatic polyols, aliphatic diols and a mixture of these compounds, wherein the process of adding the softener is controlled to retain a ratio of the average particle size of dispersed softener to the average fiber diameter in the range of about 0.01 to 15 percent: wet pressing said nascent web, creping said web from said Yankee, and recovering the paper products.

Abstract: The invention relates to hydrophilic, humectant, soft, pliant, single-ply or multi-ply absorbent papers in the form of a napkin. These humectant paper products are formed by supplying a furnish to headbox comprising: Cellulosic papermaking fiber consisting essentially of recycle fiber, hardwood fiber, softwood fiber, and mixtures thereof; and optionally up to 50% synthetic fibers and a softener which has a melting range of about 0°-40° C. wherein the softener comprises an imidazoline moiety formulated in organic compounds selected from the group consisting of alkoxylated aliphatic polyols, alkoxylated aliphatic diols, aliphatic polyols, aliphatic diols and a mixture of these compounds, wherein the process of adding the softener is controlled to retain a ratio of the average particle size of dispersed softener to the average fiber diameter in the range of about 0.01 to 15 percent: wet pressing said nascent web, creping said web from said Yankee, and recovering the paper products.

Abstract: A water-disintegratable fibrous sheet having a layered structure comprising: (a) at least one first fiber web comprising pulp of conifer and pulp of hardwood; (b) at least one second fiber web comprising pulp of conifer, having a content of pulp of hardwood less than that in said first fiber web or containing no pulp of hardwood, said first and second fiber webs forming said layered structure; and (c) a water-insoluble or water-swellable binder being added to at least one of said first and second fiber webs. The fibrous sheet excellent in water-disintegratability and strength can be obtained.

Abstract: A multifunctional tissue paper product having a combination of good wet strength, flexibility and preferably absorbency. This combination allows the tissue paper to be strong enough for use as a paper towel, yet soft enough for use as a facial tissue.

Abstract: A wire section for forming a multi-ply fiber web. The wire section includes a first belt which advances a first fiber ply toward a couch roll defining a combining section. A twin-wire zone of the wire section includes first and second wires between which a second fiber ply is initially formed in a gap former. The second wire separates from the first wire and then the first wire supporting the second fiber ply meets the first belt supporting the first fiber ply at the couch roll of the combining section to form the multi-ply fiber web. The twin-wire part is arranged upstream of the combining section along the running direction of the first belt. The second fiber ply runs on the first wire into the combining section at an angle less than 90.degree. with respect to the belt entering the combining section. The path of the wires from the forming roll to the combining section is disclosed. A suction box or arrangement holds the second fiber ply to the first wire when the first and second wires separate.

Abstract: An embossed multiple ply paper product and process for producing such product displaying aesthetically pleasing decorative attributes and exhibiting functional characteristics of softness, absorbency, and drape. The decorative attributes comprise embossed patterns of indicia displaying a high quality cloth-like appearance for a softer, more quilted look. The plies are joined in a face-to-face arrangement by selective bonds which are limited to the indicia, in order to produce more permanent decorative figures that inhibit dissipation caused by compressive forces, humidity, absorption, etc.

Abstract: Stiffness improvements for multi-ply paperboard laid from chemically pulped softwood and hardwood papermaking furnish are obtained by fiber fractionating the softwood pulp and repositioning the resulting fractions. Chemically pulped and preferably bleached softwood fiber "rejects" of a fractionation screen are redistributed into the outer plies of a three-ply, 300-350 g/m (approximately 195 #/3,000 ft.) basis weight paperboard. The fractionation "accepts" are repositioned to the center ply for a 12% to 15% increase in Taber stiffness. The short, "accept" fiber from the fractionation screen is mixed with chemically pulped hardwood fiber or modified mechanical pulp of either species for formation of the center ply on a multiformer paper machine.

Abstract: A multi-ply paper web comprises a base ply of a post-manufactured sheet such as reused old newsprint or reused office waste. An upper and/or lower ply bonded to the base ply covers any printing or contamination of the base ply, thus allowing the resulting web to be reprinted or used for writing or packaging grades. The base ply is not repulped, reducing water and energy usage in the manufacturing process. The upper and lower plies may be wet formed or dry formed. Dry-formed upper and/or lower plies result in a paper product utilizing little or no water in the manufacturing process, and no aqueous effluent. The post-manufactured base ply provides the strength ply. Multiple layers in the base ply or, alternatively, a contrast-reducing process on printed surfaces of the base ply, reduce show through of the final web.

Abstract: A multiply paper web comprises a base ply of a post-manufactured sheet such as reused old newsprint or reused office waste. An upper and/or lower ply is bonded to the base ply to cover any printing or contamination of the base ply, thus allowing the resulting web to be reprinted or used for writing or packaging grades. The base ply is not repulped, reducing water and energy usage in the manufacturing process. The upper and lower plies may be wet formed or dry formed. Dry formed upper and/or lower plies result in a paper product utilizing little or no water in the manufacturing process, and no aqueous effluent. The post-manufactured base ply provides the strength ply.

Abstract: Stiffness improvements for multi-ply paperboard laid from chemically pulped softwood and hardwood papermaking furnish are obtained by fiber fractionating the softwood pulp and repositioning the resulting fractions. Chemically pulped and preferably bleached softwood fiber "rejects" of a fractionation screen are redistributed into the outer plies of a three-ply, 300-350 g/m (approximately 195 #/3,000 ft.) basis weight paperboard. The fractionation "accepts" are repositioned to the center ply for a 12% to 15% increase in Taber stiffness. The short, "accept" fiber from the fractionation screen is mixed with chemically pulped hardwood fiber or modified mechanical pulp of either species for formation of the center ply on a multiformer paper machine.

Abstract: A multiple ply tissue paper structure is disclosed. The multiple ply tissue paper has at least two plies having discrete low density regions dispersed throughout a continous relatively high density network. One of the plies has more of the discrete low density regions per square inch than does the other ply. In one embodiment, the two plies have different calipers and macrodensities.

Abstract: The object of the present invention is to prevent delamination of an inorganic board. To attain this object, a method of manufacturing an inorganic board comprising forming a single mat by the paper making method by using slurry of raw material mixture substantially consisting of cement material, fiber material and inorganic filler inside of which is empty wherein said empty inorganic filler is effected on an alkali treatment; laminating the plural number of said single mats to form a laminated mat; and molding, incubating and curing said laminated mat.

Abstract: An inorganic board consisting of a cured base mat and a cured surface mat is manufactured by forming a surface mat by the dry method on a base mat formed by a paper making method, embossing the composite mat, and curing the embossed composite mat. Ridges each having an enlarged top are formed on the surface of the base mat when a plural number of single mats formed by the paper making method are rolled and laminated around a making roll having a surface on which a plural number of ring grooves are formed. The ridges of the base mat engage the surface mat since each ridge has an enlarged top to improve the interlaminate strength between a cured base mat and a cured surface mat of the resulting inorganic board.

Abstract: The invention provides a continuous paperboard sheet adapted to be slit longitudinally into a plurality of continuous paperboard plies, and to improved paperboard plies for forming single-layer, paperboard tubes. The paperboard sheet has a substantially constant width and includes a plurality of thick longitudinal sections and a plurality of thin longitudinal sections. The thick and thin sections are arranged in alternating relation across the width of the paperboard sheet. The sheet is slit longitudinally along the thin sections to provide a plurality of tube-forming paperboard plies.

Abstract: An oriented strand board product is provided. The board is comprised of a baseboard having three wood strand layers, the wood strands being oriented in space with respect to a board-forming machine such that a core layer is comprised of wood strands oriented generally in a random or cross-machine direction and each adjacent layer is comprised of coarse and fine wood strands oriented generally in the machine direction and wherein the wood strands comprising each adjacent layer are formed with the coarsest strands located nearest the core layer and the finest strands are located nearest the outer surfaces of each outer board layer. The OSB board product is clad with a dry felted wood fiber overlay on one planar surface of the baseboard.

Abstract: The formation of wet-pressed tissue webs useful for facial tissue, bath tissue, paper towels or the like is substantially improved by forming the wet tissue web in layers in which the second-formed layer has a consistency which is significantly less than the consistency of the first-formed layer. The fiber support index of the forming fabric is about 170 or greater. The resulting improvement in web formation enables uniform debonding during creping, which in turn provides a significant improvement in softness and a reduction in linting. Wet-pressed tissues made with this process are uniformly internally debonded, as measured by a high Void Volume Index, which is comparable to that of throughdried tissues.

Abstract: An oriented strand board (OSB)-fiberboard composite structure is comprised of a baseboard having three wood strand layers, the wood strands being oriented in space with respect to a board forming machine such that a core layer is comprised of wood strands oriented generally in a random or cross-machine direction and each adjacent layer is comprised of coarse and fine wood strands oriented generally in the machine direction. In a preferred embodiment, the wood strands comprising each adjacent OSB layer are formed with the coarsest strands located nearest the core layer and the finest strands are located nearest the outer surfaces of each outer board layer. The OSB-fiberboard composite product is clad with a wood fiber overlay on one major surface of the baseboard. The composite board is manufactured without warping, by providing particular OSB layer thicknesses, such that the lower OSB layer is about 25% to about 35% thicker than the OSB layer bonded to the fiberboard.

Abstract: A multi-ply paper web is formed by bringing a top ply liner into ply-bonding engagement with a base ply web (W.sub.B) traveling on a base ply forming wire (36). The top ply liner (W.sub.T) is formed between two co-running forming wires (10, 20) in a convex upwardly/concave downwardly curved, substantially horizontal forming zone. Dewatering in the forming zone is effected by applying sub-atmospheric air pressure solely beneath the lower surface of the top ply liner (W.sub.T) being formed. Water is removed from the upper surface of the top ply liner (W.sub.T) solely by wire tension, gravity and centrifugal force created by passing the co-running forming wires (10, 20) over the convex upwardly curved path of travel. This permits a greater concentration of pulp stock fines to remain in the upper surface of the top ply liner (W.sub.T) to effect greater ply-bonding affinity with the base ply (W.sub.B) when the two plies (W.sub.T, W.sub.B) are brought together and bonded.

Abstract: Multi-ply facial tissue paper products comprising biodegradable chemical softener compositions and a combination of a wet strength binder, either permanent and/or temporary, and a dry strength binder is disclosed.The multi-ply facial tissue paper products contain a biodegradable chemical softening composition comprising a mixture of a biodegradable quaternary ammonium compound and a polyhydroxy compound. The multi-ply facial tissue paper products also contain an effective amount of a wet strength binder, either permanent and/or temporary, and a dry strength binder to control linting and/or to offset the loss in tensile strength, if any, resulting from the use of the biodegradable chemical softening compositions. The use of both wet strength binder, either permanent and/or temporary, and dry strength binder also improves the retention of the chemical softening composition in the sheet.

Abstract: An oriented strand board product is provided. The board is comprised of a baseboard having three wood strand layers, the wood strands being oriented in space with respect to a board forming machine such that a core layer is comprised of wood strands oriented generally in a random or cross-machine direction and each adjacent layer is comprised of coarse and fine wood strands oriented generally in the machine direction and wherein the wood strands comprising each adjacent layer are formed with the coarsest strands located nearest the core layer and the finest strands are located nearest the outer surfaces of each outer board layer. The OSB board product is clad with a dry felted wood fiber overlay on one planar surface of the baseboard.

Abstract: Uncreped throughdried basesheets can be made with the caliper of the basesheet being independent of the basis weight of the basesheet. Multi-ply wipers and towels produced by plying together two or more of such basesheets having a relatively low basis weight can provide products with improved caliper and absorbency for a given strength level and the amount of fiber used.

Abstract: A laminate suitable for electrostatic discharge interference and/or electromagnetic interference shielding comprising a polymetaphenylene isophthalamide fiber layer on one or both sides of a conducting layer comprising conducting fibers and polymetaphenylene isophthalamide fibers.

Abstract: A static dissipative laminate consistently having an internal resistance less than 2.times.10.sup.6 and a resistance to ground measurement of about 5.times.10.sup.6 and a surface resistance in the static dissipative range even at a very low humidities is produced by the use of an ionic salt and an humectant in the overlay and further by the use of a special top core sheet containing 0.6-1.0% by weight of carbon fibers.

Abstract: A method of processing pulp comprises the following steps of a) mechanically refining pulp of up to 50% O.D. consistency; and b) mechanically treating the mechanically refined pulp by wringing, dewatering and compacting the mechanically refined pulp to permanently twist and kink individual fibers to a degree that is substantially irreversible when they are subsequently subjected to papermaking process steps, the refined and treated pulp having increased bulk and no reduction in Z-directional tensile over the same pulp that has not been mechanically refined and thereafter wrung, dewatered and compacted to twist and kink individual fibers. Alternately, the order of mechanically refining and mechanically treating can be reversed. The invention may have specific application to enhancing multi-layer paper products where pulp treated in accordance with the invention is utilized as core ply pulp in a multi-layer paper product.

Abstract: A decorative static dissipative high pressure laminate having a plurality of consolidated thermosetting resin impregnated layers including a core and a decor surface layer to provide a surface resistance no greater than 2.times.10.sup.9. The core comprises at least one thermosetting resin impregnated paper core sheet and at least one special thermosetting resin impregnated core sheet of predominately paper fibers and a small quantity of stainless steel fibers irregularly distributed among the paper fibers.

Abstract: A laminated paperboard product and a process for making the product and shoe insoles made therefrom. The product is formed of a first layer with a mixture of a predominance of a polyolefin fibers (preferably polyethylene) that has been treated to make it hydrophilic and long fiber softwood pulp, and a second layer formed of a mixture of the polyolefin fiber (again preferably polyethylene) and a predominance long fiber softwood pulp.When made into shoe insoles, the product has a second ply formed of a third and a fourth layer. The third layer has a composition that is similar to the second layer in that the quantity of polyolefin is greater then the quantity of wood pulp and the fourth layer has a composition that is similar to the first layer in that the quantity of polyolefin is less then the quantity of wood pulp.

Abstract: A non-woven fibrous mat of generally random fiber orientation with built up lines or strips of fiber formed therein directionally oriented to enhance the strength and/or appearance of a mat and a method and apparatus for efficiently producing the same by differentially controlling dewatering in a wet mat process.

Abstract: There is disclosed a tactile imaging paper comprising a tactile sheet and a backing sheet laminated together. The tactile sheet is a cellulosic sheet formed from a highly dilute furnish of from 30% to 60% chemically modified high alpha pulp, 35% to 70% solftwood pulp (or a mixture of softwood pulp and hardwood pulp with the hardwood pulp comprising up to 50% of the mixture), and 0.5% to 6% polyvinyl alcohol fiber. The tactile sheet is formed from the furnish without any wet pressing of the tactile sheet. Once the tactile sheet is dry, it is dry calendered to a density of from 0.3 to 0.9 grams per cubic centimeter. Moreover, the tactile sheet has a porosity of greater than 1000 centimeters per minute. The tactile sheet has a basis weight from 75 to 200 grams per square meter and with a laminated backing sheet the tactile imaging paper has a basis weight of about 190 gsm.

Abstract: Flash expansion of moist multi-layered boards wherein each layer comprises aramid floc bonded by aramid fibrid results in high strength, low density aramid boards.

Abstract: A process for preparing a confidential postcard contains dehydrating a starting paper material containing 25 to 45% by weight of fibers of a thermoplastic resin and 55 to 75% by weight of fibers of a natural plant to thereby form a paper layer, heating, during or after drying, the paper layer at a temperature not lower than a softening point of the thermoplastic resin fibers to thereby obtain a paper sheet in which the fibers of the thermoplastic resin retain fiber shape and are entangled with the fibers of the natural plant, inscribing a statement to be kept confidential on the paper sheet, superposing the paper sheet to conceal the statement and attaching provisionally the superposed paper sheet by heating under pressure at a temperature not lower than a softening point of the thermoplastic resin fibers to obtain the confidential postcard. The confidential postcard is capable of being peeled off with the statement on the paper sheet being left intact.

Abstract: An insulating polyolefin laminate paper and a method for producing such a paper in which first and second fiber paper layers are laminated to a polyolefin film layer. The fiber paper layers have an impermeability of 20 to 4000 Gurley-seconds. At least one of the fiber paper layers is mechanically deformed in such a manner that irregularities are produced having a depth of 2 to 50% of the thickness of the fiber paper layer. The mechanical deformation is accomplished prior to lamination. Before lamination, the water content of the fiber paper layers is controlled to be no more than 4%. Preferably, the thickness of the fiber paper layers is at least 30 microns. Furthermore, an electric power supply cable includes an insulating polyolefin laminate paper as an insulating layer.