MXPA97000759A - Soft hygienic paper of fibers asperas decelul - Google Patents

Abstract

The present invention relates to a soft toilet paper comprised of chemically softened cellulose fibers, said cellulose fibers comprised of a sufficient amount of coarse fibers to raise the average mixed roughness of the toilet paper to more than about 11.0 mg / 100m, where said cellulose fibers have a reduced coefficient of friction (CORF), in percentage points, related to their average mixed roughness (C), in mg / 100m, by the equation: CORF > 4.27 * C-44.23 wherein said toilet paper has a specific tensile strength between about 9 and about 25 g / inch / g / m2, and a density between 0.05 and 0.20 g / c.

Description

SOFT HYGIENIC PAPER OF HEAVY CELLULOSE FIBERS TECHNICAL FIELD This invention relates, in general, to toilet paper; and more specifically to sanitary toilet paper made from low grade cellulose pulps characterized as low grade, due to its relatively high roughness.

BACKGROUND OF THE INVENTION As the global supply of natural fibers is among the economic increase and environmental scrutiny, the pressure rises in the use of low-grade cellulose fibers such as those produced from recycled paper and those produced from mechanical or chemical processes - Higher performance mechanics. Unfortunately, said fibers, when added to sanitary papers, give rise comparatively to a severe deterioration of the characteristic of the product that is mostly requested by consumers of sanitary paper, namely the aesthetic qualities and more specifically the softness. The characteristic of the faulty fiber is mainly the roughness of thickness. The said low grade cellulose fibers typically have a high roughness. This contributes to the loss of the velvety sensation imparted by the selected first class fibers due to its looseness. U.S. Patent 4,300,981, Cars ens, issued November 17, 1981, and incorporated herein by reference, explains the texture and surface qualities imparted by these premium fibers. Desirable surface qualities are absent when low-grade fibers are selected, if the low-grade fibers have high roughness. In the case of mechanical or chemical-mechanical discharged fiber, the high roughness is due to the retention of the non-cellulose components of the substance coming from the wood, such components including lignin and the so-called hemicelluloses. This makes each fiber weigh more without increasing its length. Recycled paper may also tend to have a high content of mechanical pulp, but, even when all due care is exercised in selecting the grade of waste paper to minimize this, high roughness often still occurs. It is thought "that this is due to the impure mixture of fiber morphologies" that occur naturally when mixing paper from many sources to make a recycled pulp. For example, a certain waste of paper could be selected because it is of primary North American hardwood origin; however, frequently one will find a vast contamination of the roughest softwood fibers, even of most pernicious species such as the variations of the southern pine of the United States.During the history of papermaking, many Inventors have directed their energies towards overcoming the limitations of lower quality fibers to make them acceptable for the uses described herein.Of the many chemical additives that have been proposed for use in softening papers, no system has proven to be sufficient. effective for truly soft paper from the previously described supplies, such as being rough, unless excessive or unnecessary amounts of additives resulted in comparatively expensive products that could accordingly be relegated to specialty niches unavailable to the vast majority of the population. Therefore, it is an object of the present invention to provide er a low density fibrous paper structure that has a tactically pleasing response. It is another object of the invention to incorporate a critical amount of fibers normally considered as being rough and inferior with respect to the previous object. It is another object of the present invention to provide the paper without the excessive use of chemical treatments that are added to the expenses of production and distribution of the product. These and other objects are obtained using the present invention as will be taught in the following disclosure.

BRIEF DESCRIPTION OF THE INVENTION It has been found that unexpected smoothness can be achieved by a ratio between the roughness of the fibers making up the paper and the coefficient of friction of the supplied fibers from which the paper is made. This relationship makes it possible to provide a soft paper without the need to load additives unnecessarily to cover the roughness of the coarse fibers. The present invention is a soft toilet paper comprised of chemically softened cellulosic fibers. The chemically softened cellulosic fibers comprise a sufficient amount of coarse fibers to raise the average mixed roughness of the toilet paper to more than about ll.O mg / 100m. "Chemically smoothed" cellulosic fibers have a reduced coefficient of friction (CORF, in percentage points) related to their average mixed roughness (c), in mg / lOOm, by the equation: CORF > 4.27 * C - 44.23 The soft toilet paper has a specific tensile strength between about 9 and about 25gr / inch / g / m2 and a density between about 0.05 to about 0.20 g / cm3. In its preferred embodiment, the invention provides an object treatment, capable of essentially coating the fibers, in relation to their specific surface, with a substantive chemical softening, preferably in amounts ranging from about 0.05% to about 2.0%, by weight. Preferred chemical softeners include quaternary ammonium compounds having the formula: In the structure mentioned above, each R is a hydrocarbyl group of C ^ Cjj, preferably tallow, R2 is an alkyl or hydroxyalkyl group of 0, -04, preferably C ^ Cj alkyl, X "is compatible anion, such as a halide (eg, chlorine or bromine) or methyl sulfate, as discussed in S ern, Ed.

Bailey's Industrial Oil and Fat Products, Third Edition, John Wiley and Sons (New York 1964), tallow is a material that occurs naturally, having a variable composition. He Table 6.13 in the above-identified reference, edited by Swern indicates that typically 78% or more of tallow fatty acids contain 16 or 18 carbon atoms. Typically, half of the fatty acids present in sebum are unsaturated, primarily in the form of oleic acid. Both synthetic and natural seals fall within the scope of the present invention. Preferably, each R1 is C16-C18 alkyl, most preferably each R, is straight chain C18 alkyl. Preferably, each R 2 is methyl and X "is chloro or methyl sulfate Examples of quaternary ammonium compounds suitable for use in the present invention include the well known dialkyldimethylammonium salts such as ditallowdimethylammonium chloride, ditalbodimethylammonium methyl sulfate, di ( hydrogenated) sebodimethylamine with di (hydrogenated) tallow dimethylammonium methyl sulfate, being preferred.This particular material is commercially available from Witco Chemical Company Inc. of Dublin, Ohio under the tradename "Varisoft®137." Variations of biodegradable mono and diester of the quaternary ammonium compound can also be used, and are intended to fall within the scope of the present invention All percentages, scales and proportions herein are by weight unless otherwise specified.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a flowchart is "quemático" representing a method to produce the preferred cellulose pulps, where the length classification stage is first performed, followed by a centrifugation step. Figure 2 is a schematic flow chart depicting an alternate method for producing the preferred cellulose pulps, wherein a spin stage is first performed, followed by a length sorting step. The present invention is described in more detail below.

DETAILED DESCRIPTION OF THE INVENTION Briefly, the present invention is a low extractive toilet paper which has hitherto not achieved a level of smoothness when the roughness of its supply is taken into account. It has been found that it is possible to achieve these unexpected levels of smoothness by reducing the coefficient of friction of the surfaces of the individual fibers in relation to their surface area. As used herein, the term coefficient of friction refers to the coefficient of friction as determined from the force required to drag a molten glass harrow through the smooth surface of a paper sample, which has been prepared using the standard TAPPI T-205 method. Details of the method used for the measurement are provided below, however the coefficient of friction must be determined by other methods that produce comparable values. The term reduced friction coefficient, denoted by the acronym CORF throughout this specification, and expressed in units of percentage points, refers to the amount of percentage by which the coefficient of friction is reduced via the addition of the softener chemical. In other words, to measure the CORF of a supplied fiber, a standard sheet is prepared using a sample of the fibers without chemical softener and a standard sheet is prepared using a sample of the fibers after the addition of the chemical softener. The coefficient of friction is measured using each sheet, and the CORF is calculated using the following formula: CORF = COFD - COFA x 100 COFB Where CORF is the reduced coefficient of friction and C0FB and COFA are the coefficients of friction of the sheets made from untreated fibers and treated fibers respectively. As used herein, the term "chemical softener" refers to a compound capable of increasing the lubricating capacity of the fibers for making paper, although being essentially substantive to the fibers, ie, it will remain in the fibers even when the fibers are dispersed. in water The present invention preferably contains from about 0.05% to about 2.0% by weight, on a dry fiber basis, of a chemical softener. A more preferred form of chemical softener is 0.05% to 2.0% of a quaternary ammonium compound having the formula: In the aforementioned structure, each R is a hydrocarbyl group of C 1 -C 2, preferably tallow, R 2 is an alkyl or hydroxyalkyl group of C, -C 6, preferably C 1 C 2 alkyl, X "is compatible anion, such such as a halide (eg, chlorine or bromine) or methyl sulfate As discussed in Swern, Ed. in Bailey's Industrial Oil and Fat Products, Third Edition, John Wiley and Sons (New York 1964), tallow is a Naturally occurring material having a variable composition Table 6.13 in the above-identified reference, edited by Swern, indicates that typically 78% or more of tallow fatty acids contain 16 or 18 carbon atoms. Fatty acids present in sebum are unsaturated, primarily in the form of oleic acid.Sol both synthetic and natural seals fall within the scope of the present invention Preferably, each R1 is C16-C18 alkyl, most preferably each R1 is C18 alkyl of Straight chain. Preferably, each R 2 is methyl and X "is chloro or methyl sulfate Examples of quaternary ammonium compounds suitable for use in the present invention include the well known dialkyldimethylammonium salts such as ditallowdimethylammonium chloride, ditalbodimethylammonium methyl sulfate, di ( hydrogenated) sebodimethylammonium, with di (hydrogenated) tallow dimethylammonium methyl sulfate, being preferred.This particular material is commercially available from Witco Chemical Company Inc. of Dublin, Ohio under the tradename "Varisoft®137." Additional examples of quaternary ammonium compounds Suitable and preferred methods for adding said compounds to cellulose fibers are described in U.S. Patent 5,240,562, Phan et al., issued August 31, 1993, and incorporated herein by reference. biodegradable quaternary ammonium compound can also be used, and are intended s to fall within the scope of the present invention. These compounds have the formula: In the structures mentioned above, each R, is an aliphatic C, 3-C, 9 hydrocarbyl group, such as tallow, R 2 is an alkyl or hydroxyalkyl group of C, -C 6, preferably alkyl of 0, -Cj or a mixture of the same, X * is compatible anion, such as a halide (eg chlorine or bromine) or methyl sulfate.

Preferably, each R is C6-C18 alkyl, most preferably each R is straight chain C8 alkyl, and R is a methyl. Other preferred chemical softeners, suitable for use in the hygiene papers of the present invention include polysiloxane compounds, preferably amino-functional polydimethyl polysiloxane compounds. In addition to said substitution with amino-functional groups, the effective substitution can be made with carboxyl, hydroxyl, ether, polyether, aldehyde, ketone, amide, ester and thiol groups. Of these effective substituent groups, the family of groups comprising amino, carboxyl and hydroxyl groups are more preferred than the others; and amino-functional groups are more preferred. Suitable types of such polysiloxanes are described in U.S. Patent No. 5,059,282, Ampulski et al., Issued October 22, 1991, and incorporated herein by reference. Examples of commercially available polysiloxanes include DOW 8075 and DOW 200 which are available from Dow Corning; and Silwet L720 and Ucarsil EPS that are available from Union Carbide. Still other preferred chemical softener additives suitable for the present invention include nonionic surfactants selected from alkyl glycosides, including alkyl glycoside esters such as Crodesta® SL-40 which is available from Croda, Inc. (New York, NY); alkyl glycoside ethers as described in U.S. Patent 4,011,389, issued to W.K. Langdon et al., March 8, 1977; alkyl polyethoxylated esters such as Pegosperse® 200 ML available from Glyco Chemicals, Inc. (Greenwich, CT); alkyl polyethoxylated ethers and esters such as Neodol® 25-12 available from Shell Chemical Co .; sorbitan esters such as Span 60 from ICI America, Inc., ethoxylated sorbitan esters, propoxylated sorbitan esters, mixture of ethoxylated / propoxylated sorbitan esters, and polyethoxylated sorbitan alcohols such as Tween 60, also from ICI America, Inc. It should be understood that, the above listing of suitable chemical softeners are intended to be merely exemplary in nature, and should not be understood as limiting the scope of the invention. It has been found that compounds, such as the aforementioned quaternary ammonium compounds in such low amounts (ie, from 0.05% to 2.0%) have a high concomitant economic value. In fact, in these low amounts, for the exposed paper, it is not necessary to counteract any hydrophobicity through the use of polyhydroxy compounds or other wetting agents that would result in additional savings. As used herein, the term "average mixed roughness" refers to the determined roughness in a finished fibrous paper product, without considering whether the product is composed of several supplies of different roughness values. The method for determining the roughness of cellulose fibers is described in detail below. The average mixed roughness can also be determined for a product comprised of a mixture of different types of cellulose fibers from the roughness of the individual fibers, of which the product comprises. The exact proportions by weight of the different types of fibers need to be known in order to perform this calculation. To do this, the following formula is used to determine the resulting average mixed roughness C when two types of fiber, type 1 and type 2, which have roughness Cl and C2, respectively, are mixed in weight fractions fl and f2, respectively: C = Cl * (1 + fl / f2) 1 + (f2 / fl) * (C1 / C2) The toilet papers of the present invention are comprised of cellulose fibers having an average mixed roughness greater than about 11.0 mg / m, more preferably, greater than about 12 mg / 100 m. A preferred method for producing cellulose pulps having a desired combination of fiber length and fiber roughness is described in United States Patent Application No. 08 / 082,683, Vinson, filed on June 24, 1993, and incorporated herein by reference. As used herein, the term "cellulose fibers" refers to fibrous material that occurs naturally, derived from wood or other biological material. Wood derived materials are of particular interest. Wood cellulose fibers can be employed from a variety of sources to produce the products according to the present invention. These include chemical pulps, which are purified to remove substantially all of the lignin from the wood substance. These chemical pulps include those made by either the alkaline kraft (sulphate) process or the acid, sulfite. Also the applicable wood fibers can be derived from mechanical pulps, a term which as used herein, refers to chemothermomechanical also as waste wood, thermomechanical, and semi-chemical pulps, all of which maintain a substantial portion of lignin from of the wood substance. Both pulps of wood and soft wood pulps can be used, also as mixtures of the two. As used herein, the terms pulp of hardwood and softwood pulp, refer to fibrous pulp derived from woody substances of deciduous trees (angiosperms) and coniferous trees (gymnosperms), respectively. Also applicable to this invention are fibers derived from recycled paper, which may contain any or all of the above categories, also as minor amounts of other fibers, fillers, and adhesives used to facilitate the manufacture of original paper. Fibers derived from recycled paper made with chemical pulp fibers and comprising a mixture of hardwood fibers and softwood can also be used to produce products according to the present invention. As used herein, the term "recycled paper" generally refers to paper that has been collected in an attempt to release its fibers and reuse them. These can be pre-consumer, as they could be generated in a paper mill or printing workshops, or post-consumer, such as those from the collection of homes and offices. Recycled papers are classified in different grades by merchants to facilitate their reuse. A recycled paper grade of particular value in the present invention is tape paper. The tape paper is generally comprised of chemical pulps and typically has a ratio of hardwood to softwood of from about 1: 1 to about 2: 1. Examples of tape papers include loops, books, photocopy paper, and the like. Preferably, the cellulose fibers used to make the toilet paper of the present invention comprise at least 10%, and more preferably from about 20% to about 60% by weight, of coarse or rough cellulose fibers selected from the group consisting of of recycled fibers, chemothermomechanical fibers and mixtures thereof. Softness, as used herein, refers to the quality to the touch of a toilet paper, as judged relatively by a panel of experts and reported in average panel judged units. It is known that softness is affected by structural artifacts of papermaking different from the morphology of fiber as disclosed herein. For exampleIt is well known to those skilled in the art that the softness of sanitary paper is a function of its weight and resistance to stress. This is also true for articles made according to the present invention. The inventors express the combination of these parameters as a relationship where the tensile strength, in g / inch, is divided by the basis weight, in g / m2. This relationship is referred to herein as the specific stress resistance. The specific tension useful for the present invention ranges from about 11 g / inch / g / m2 to about 25 g / inch / g / m2, and more preferably, from about 11 g / inch / g / m2 to 17 g / inch / gr / m2. The softness is also affected by the volume resulting from the type of formation and drying performed in papermaking. For example, U.S. Patent 3,301,746 issued to Sanford and Sisson in 1967, was instrumental in defining the means of preparing exceptionally soft paper useful for sanitary papers and the like. This technique recognizes the importance of density in providing softness.

The term density, as used herein, is calculated from the thickness and weight per unit area, where the thickness is determined using any properly calibrated calibrator capable of subjecting the sample to a uniform compression load of 95 gr. / in2. The density scales useful for the present invention range from about 0.05 gr / cm3 to about 0.2 gr / cm3, preferably from about 0.08 gr / cm3 to about 0.15 gr / cm3. As used herein, the term "centrifugal screening" refers to a pressure sifter such as the Centrisortes Model 100, a trade name of Bird Machinery Corporation of South Walpole, MA, equipped with a sieve basket with hole sizes capable of separating the fibers in an inlet stream into two fractions having a measurable difference in length. The term "fiber length", as used herein, refers to the average length of heavy fiber as determined in the Kajaani FS-200, described in detail below. Preferably, the toilet papers of the present invention have an average mixed fiber length between about 1 mm and about 1.5 mm. The term hydraulic cyclone, as used herein, refers to a device such as a 3-inch Centricleaner, a trade name of the Sprout-Bauer Company of Springfield, Ohio.

A. HYGIENIC PAPERS The present invention is a soft toilet paper comprised of chemically softened cellulose fibers. The chemically softened cellulose fibers comprise a sufficient amount of coarse or rough fibers to raise the average mixed roughness of the toilet paper to more than about 11.0 mg / 100 m. Chemically smoothed cellulose fibers have a reduced coefficient of friction (CORF, in percentage points) related to the average mixed roughness (C), in mg / lOOm, by the equation: CORF > 4.27 * C-44.23, more preferably, CORF > 4.75 * C - 44.23 The toilet papers have a specific tensile strength between about 9 and about 25 g / inch / g / m2 and a density between about 0.05 and about 0.20 g / cm3. The present invention is useful with toilet paper in general, including but not limited to conventionally pressurized toilet paper; densified toilet paper with high volume pattern; and unconsolidated, high-volume toilet paper. The toilet paper may be of a homogeneous or multi-layered construction; and the toilet paper products made there can be single-sheet or multi-sheet. The toilet paper preferably has a basis weight of between about 10 g / m2 and about 65 g / m2, and a density of about 0.6 g / cm3 or less. More preferably, the basis weight will be about 40 g / m2 or less, and the density will be about 0.3 g / cm 3 or less. More preferably, the density will be between about 0.05 g / cm3 and about 0.2 g / cm3, and most preferably, from about 0.08 g / cm3 to about 0.15 g / cm3. see column 13, lines 61 to 67, of U.S. Patent 5,059,282 (Ampulski et al.), issued October 22, 1991, which describes how the density of toilet paper is measured. (Unless "otherwise specified, all paper-related amounts and weights are on a dry basis.) In a preferred embodiment of the present invention, the toilet papers are of a single-ply, multi-ply construction. Preferably, the sheet comprises three superimposed layers, an inner layer and two outer layers, with the inner layer being located between the two outer layers. The inner layer preferably comprises cellulose fibers with an average length of heavy length of at least about 1 irim, and each of the two outer layers preferably comprises fibers with an average length of heavy length of less than about 1 mm. In this preferred modality, the inner layer comprises from about 15% to about 35% of the total weight of the sheet. The coarse or rough cellulose fibers are selected from the group consisting of recycled fibers, chemical-thermomechanical fibers and mixtures thereof. The thick fibers are preferably located in the outer layers where they comprise at least 10% and more preferably from about 20 to about 605 of the total weight of the sheet and at least about 12%, and more preferably from about 25 to about 75. % by weight, of the outer layers. Conventionally compressed toilet paper and methods for making such paper are well known in the art. Said paper is typically made by depositing a supply for making paper on a foraminous forming wire, often referred to in the art as a Fourdrinier wire. Once the supply is deposited in the forming wire, it will be referred to as a screen. The weft is drained by pressing the weft and drying at elevated temperatures. The particular technique and typical equipment for making frames according to the described process are well known to those skilled in the art. In a typical process, a supply of low consistency pulp is provided from a pressurized head. The head has an opening for supplying a thin pulp supply reservoir over the Fourdrinier wire to form a wet web. The web is then typically dewatered to a fiber consistency of between about 7% and about 25% (total basis weight of the web) by vacuum draining and further dried by pressing operations, wherein the pressurized web is subjected to pressure. opposed mechanical members, for example, cylindrical rollers. The dewatered web is then pressed and dried by a current drum apparatus known in the art as a Yankee dryer. The pressure in the Yankee dryer can be developed by mechanical means such as an opposite cylindrical drum against the weft. Multiple Yankee dryer drums can be employed, whereby additional compression is optionally incurred between the drums. The toilet paper structures that are formed are subsequently referred to as compressed, conventional, toilet paper structures. Said sheets are considered to be consolidated, since the whole web is subjected to substantially mechanical compression forces while the fibers are moistened and then dried even in a compressed state. Preferably, the toilet papers of the present invention are densified in pattern. A densified pattern toilet paper is characterized by having a relatively high volume field of relatively low fiber density and an array of densified areas of relatively high fiber density. The high volume field is alternatively characterized as a field of pillow regions. The densified zones are referred to alternately as conjuncture regions. The densified zones are scattered within the high volume zone. The densified zones may be discretely separated within the high volume field or may be interconnected, either totally or partially, within the high volume field. The patterns may be formed in a non-ornamental configuration or they may be formed to provide a design or ornamental designs on the toilet paper. Preferred processes for making paper webs with densified patterns are described in U.S. Patent No. 3,301,746 (Sanford et al.), Issued January 31, 1967; U.S. Patent No. 3,974,025 (Ayers), issued August 10, 1976; and U.S. Patent No. 4,191,609 (Trokhan) issued March 4, 1980; and U.S. Patent No. 4,637,859 (Trokhan) issued January 20, 1987; all of which are incorporated by reference. In general, the densified pattern webs are preferably prepared by depositing a supply for making paper on a foraminous forming wire such as a Fourdrinier wire to form a wet web and then juxtaposing the web against an array of supports. The frame is compressed against the arrangement of supports, resulting in areas densified in the frame in the locations geographically corresponding to the points of contact between the array of supports and the wet frame. The uncompressed remnant of the frame during this operation is referred to as the high volume field. This high-volume field can be further dedensified by the application of pressurized fluid, such as with a vacuum-type device or a blow-through dryer, or by mechanically pressing the weft against the arrangement of supports. The web is dewatered, and optionally pre-dried, in such a manner as to substantially avoid compression of the high volume field. This is preferably achieved by pressurized fluid, such as emo with a vacuum-type device or bypass blow dryer, or alternatively by mechanically pressing the weft against the array of supports where the high field is not compressed. volume. The operations of dewatering, optional pre-drying and formation of densified zones can be integrated or partially integrated to reduce the total number of processing steps carried out. Subsequent to the formation of the densified zones, dewatering, and optional predrying, the web is completely dried, preferably still avoiding mechanical compression. Preferably, from about 8% to about 55% of the surface of the toilet paper comprises densified joints having a relative density of at least 125% of the density of the high volume field. The arrangement of supports is preferably a stamping carrier fabric having a patterned movement of joints that operate as the array of supports facilitates the formation of the densified zones upon the application of pressure. The pattern of joints constitutes the arrangement of the supports previously referred to. Suitable stamping carrier fabrics are described in U.S. Patent No. 3,301,746 (Sanford et al.), Issued January 31, 1967; U.S. Patent No. 3,821,068 (Salvucci et al.), issued May 21, 1974; U.S. Patent No. 3,974,025 (Ayers), issued August 10, 1976; U.S. Patent No. 3,573,164 (Friedberg et al.), issued March 30, 1971; U.S. Patent No. 3,473,576 (Amneus), issued on October 21, 1969; The Patent of the United States No. 4,239,065 (Trokhan), issued December 16, 1980; and U.S. Patent No. 4,528,239 (Trokhan), issued July 9, 1985, all of which are incorporated by reference. Preferably, the supply is first formed in a wet web on a foraminous forming carrier, such as a Fourdrinier wire. The weft is drained and transferred to a patterned fabric. The supply may alternatively be deposited initially on a foraminous carrier that also operates as a printing fabric. Once formed, the wet web is drained and, preferably, thermally pre-dried to a selected fiber consistency of between about 40% and about 80%. Preferably, the drainage is carried out with suction boxes or other vacuum devices or with through blow dryers. The embossing pattern of the printing fabric is stamped on the weft as discussed above, before the weft is completely dried. One method to achieve this is through the application of mechanical pressure. This can be done, for example, by compressing the space of a roller supporting the printing fabric against the face of a drying drum, such as a Yankee dryer, wherein the screen is disposed between the roll and drum space. of drying. Also, preferably, the web is molded against the printing fabric before it is finished drying by applying pressurized fluid with a vacuum device such as a suction box, or with a through blow dryer. The pressurized fluid can be applied to induce the stamping of the densified zones during the initial drainage, in a subsequent stage of the process, separately, or in combination thereof. Unbound, unconsolidated toilet paper structures are described in U.S. Patent No. 3,812,000 (Salvucci et al.), Issued May 21, 1974, and U.S. Patent No. 4,208,459 (Becker et al. others), issued on June 17, 1980, both of which are incorporated by reference. In general, uncondensed, unconsolidated, hygienic toilet paper structures are prepared by depositing a paper supply on a foraminous forming wire such as a Fourdrinier wire to form a wet weft, draining the weft and further removing the water without mechanical compression. until the web has a fiber consistency of at least about 80%, and slide the web. Water is removed from the weft by vacuum dewatering and thermal drying. The resulting structure is a high volume, soft but weak sheet of relatively uncompressed fibers. Preferably a bonding material is applied to the portions of the weft before sliding. Compressed paper structures, densified without pattern, are commonly known in the art. In general, compressed, densified, unpatterned toilet paper structures are prepared by depositing a supply to make paper in a foraminous wire such as a Fourdrinier wire to form a wet weft, draining the weft and further stirring the water with the aid of a uniform mechanical compression (pressing) until the weft has a consistency of 25-50%, transfer the weft to a thermal dryer such as a Yankee and slide the weft. The total water of the plot is removed by means of vacuum, mechanical pressing and thermal. The resulting structure is strong and generally of particular density, but very low in volume, absorbency and softness.

B. DETERMINATION OF THE ASPEREZA AND LENGTH OF FIBER As used herein, the term "average fiber length" refers to the length of the average length of heavy fiber as determined with a suitable fiber length analysis instrument such as a Kajaani Model FS fiber analyzer. -200 available from Kajaani Electronics of Norcross, Georgia. The analyzer is operated according to the manufacturer's recommendations with the report establishing the scale from 0 mim to 7.2 mm and the profile is established to exclude fibers less than 0.2 mm in length from the calculation of fiber length and roughness. Particles of this size are excluded from the calculation because they are widely believed to consist of non-fibrous fragments that are not functional for the uses toward which the present invention is directed. The term "roughness", abbreviated "C" in the algebraic formula contained herein, refers to the mass of the fiber per unit fiber length without weighing reported in units of milligrams per 10 meters of fiber length without weighing ( mg / 100m) as measured using a suitable fiber roughness measuring device such as the aforementioned Kajaani FS-200 analyzer. The roughness C of the pulp is an average of three roughness measurements of three fiber samples taken from the pulp. The operation of the analyzer to measure the roughness is similar to the operation to measure the length of the fiber. Care must be taken in the preparation of the sample to ensure an accurate sample weight that enters the instrument. An acceptable method is to dry two weight aluminum plates for each fiber sample in a drying oven for thirty minutes at 110 ° C. The dishes are then placed in a desiccator that has a suitable desiccant such as calcium sulfate anridide for at least 15 minutes to cool. The dishes must be handled with tweezers to avoid contamination with oil or moisture. The two plates are removed from the desiccator and immediately weighed together to the nearest 0.0001 grams. Approximately one gram of a fiber sample is placed in one of the dishes, and the two dishes (one empty) are placed uncovered in the drying oven for a period of at least 60 minutes at 110 ° C to obtain a fiber sample entirely dry. The plate with the fiber sample is then covered with the empty plate before removing the dishes from the oven. The dishes and the sample are then removed from the oven and placed in a desiccator for at least 15 min. to cool. The covered sample is removed and immediately weighed with the dishes to 0.0001 grams or so. The weight previously obtained from the dishes can be subtracted from this weight to obtain the weight of the sample of entirely dry fiber. This fiber weight is referred to as the initial weight of the sample. An empty 30 liter container is prepared by wiping it and weighing it on a scale capable of at least 25 kgms. of capacity with an accuracy of 0.01 grams. A standard TAPPI disintegrator, such as the British disintegrator referred to in the TAPPI T205 method, is prepared by cleaning its container to remove all fibers. The weight of the initial sample of the fibers is drained into the disintegrating container, ensuring that all fibers are transferred to the disintegrator. The fiber sample in the disintegrator is diluted with approximately 2 liters of water and the disintegrator is operated for 10 minutes. The content of the blaster is washed in the 30 liter container, making sure that all the fibers are washed in the container. The sample in the 30 liter container is then diluted with water to obtain a suspension of water-fiber weighing 20 kgms., 0.01 grams more or less. The sample beaker for the Kajaani FS-200 is cleaned and weighed to 0.01 grams or so. The suspension in the 30-liter container is agitated with vertical and horizontal strokes, taking care to produce a circular movement "that would tend to centrifuge the fibers in the suspension. A measurement of 100 grams accurate to 0.01 grams or so is transferred from the 30 liter container to the Kajaani cup. The weight of the fibers in the Kajaani beaker, in milligrams, is obtained by multiplying five (5) times the initial weight of the sample (as recorded in grams).

This weight of the fiber, which is accurate to 0.01 milligrams, falls into the profile of Kajaani FS-200. A minimum length of 0.2 mm is introduced into the Kajaani profile, such that 0.02 mm is the minimum fiber length considered in the calculation of the roughness. A preliminary roughness is then calculated by the Kajaani FS-200. The roughness is obtained by multiplying this preliminary roughness value by a factor that corresponds to the heavy cumulative distribution weight of the fibers with a length greater than 0.02 mm. The instructions of FS-200 provide a method to obtain this weight of heavy distribution. However, the values are reported as a percentage and are accumulated starting at the fiber length "0". To obtain the factor described above, the heavy weight cumulative distribution of the fibers with lengths less than 0.2 mm (which is provided as an output of the instrument) is obtained from the instrument's deployer. This display value is subtracted from 100, and the result is divided by 100 to obtain the factor corresponding to the cumulative weight-loaded distribution of fibers with length greater than 0.2 mm. Therefore the resulting roughness is a measure of the roughness of those fibers in a fiber sample having a fiber length greater than 0.2 mm. The measurement of the roughness is repeated, starting with drying in the oven 2 heavy plates and a sample of fiber to obtain 3 values of roughness. The roughness value C used herein is obtained by averaging the three values of asperities and converting the units to express the value in mg / 100m.

C. FRICTION COEFFICIENT The coefficient of friction is obtained using a KES-4BF surface analyzer with a modified friction test as described in "Methods for Measuring the Mechanical Properties of Toilet Paper", Ampulski, and others at the 1991 International Paper Physics Conference published by the TAPPI press and incorporated herein by reference. The substrate used for the evaluation of friction as described herein, is a sheet prepared in the laboratory, prepared according to the TAPPI standard T-205 incorporated herein by reference. The friction is measured on the smooth side of the sheet (the side that dries against a metal plate according to the method). The substrate is advanced at a constant speed of 1 m / sec for the measurement and the friction test of the standard test of the instrument is modified to about 2 cm. of the glass frit 40-60 m in diameter. When a normal force of 12.5 grms is used. In the test and until now the specific translation speed for the substrate, is coefficient of friction can be calculated by dividing the frictional force by the normal force. The frictional force is the lateral force in the test during the recording, an output of the instrument. The average coefficient of friction obtained by an individual record in the forward direction and an individual record in the opposite direction is reported as the coefficient of friction for the sample. Therefore to measure the reduced friction coefficient of a fiber supply, a standard sheet is prepared using a sample of the fibers and chemical stabilizer and a standard sheet is prepared using a sample of the fibers after the addition of the chemical softener. The coefficient of friction is measured using each sheet, and the CORF is recorded using the following formula: C0RF = C0Fr - C0FA X 100 C0FB Where the CORF is the reduced coefficient of friction and C0FB and C0FA are the coefficient of friction of the sheet made from untreated fibers and those from fibers treated with chemical softener, respectively.

THE POINT OF HEAVY FIBERS OF CELLULOSE Even though many suitable sources of harsh cellulose fibers can be applied to make toilet paper according to the present invention, two modalities are preferred for their practice. A preferred embodiment employs a thermomechanical chemical pulp derived from hardwood fibers, such as Aspen CTMP. A second preferred embodiment employs recycled fibers. If recycled fibers are used in the present invention, it is preferred that they be preconditioned according to the following process steps in order to more favorably dispose them to the use of the product. These include two basic arrangements of two-stage fractionation processes comprising a length classification stage and a centrifugation stage. Figure 1 is a flow chart illustrating an arrangement that can be used to produce preferred cellulose pulps for use in the toilet papers of the present invention. In this arrangement, the length classification stage is carried out first, followed by the centrifugation step. In Figure 1, an aqueous suspension 21 comprising wood pulp fibers is directed to form the inlet stream to the length classification stage 32. A satisfactory length classifier is a centrifugal pressure screw such as a Bird "Centrisorter ", manufactured by the Bird Escher Wyuss Corporation of South Walpole, Massachusetts. The suspension 21 is processed in the length sorting stage 32 to provide an acceptance current 33 of the sorting stage 32 and a rejecting current 34 of the sorting stage 32. The rejecting current 34 comprises the fibers having a average fiber length exceeding that of the fibers in the acceptance stream 33, the length classification step 32 is configured and operated as described below to provide the acceptance current 33 having an average fiber length that is less 20% and preferably at least 30% less than the average fiber length of the reject stream comprising the suspension 34. The fibers in the reject stream 34 are directed to extreme alternate uses where the targeted characteristics of the present invention are less valuable. In this respect they can be mixed with other reject streams, kept separate or discarded. Without being limited by theory, the weight of the fiber of the acceptance stream 33 of the length sorting stage 32 must be between about 30 to 70% of the weight of the fiber of the input stream to the classification step of length 32, such that there is approximately 30 to 70% by mass separated from the fibers entering the length classification stage 32, between the current acceptance current 33 and the reject current 34. Said mass separation It is desirable to ensure that the length sorting stage 32 functions to fractionate the input current by the fiber length, instead of only operating to remove debris such as knots and chips from the input stream. At least a portion of the acceptance stream 33 of the length sorting stage 32 is directed as shown in Figure 1 to provide an input stream 41 to a second fractionation stage comprising a centrifugation step 42. Successful centrifugation step 42 comprises one or more hydraulic cyclones, such as 3-inch hydraulic cyclones manufactured by CE Bauer Company of Springfield, Ohio. For the best operation of the centrifugation stage 42, it may be necessary to adjust the consistency of the inlet stream 41 to the centrifugation stage 42 before processing the inlet stream 41 in the centrifugation step 42. For example, if it is desirable to remove the water from the inlet stream. 41 to increase the consistency of the inlet stream 41, a suitable screen 36 can be placed intermediate to the length sorting stage 32 and to the centrifugation step 42, as illustrated in Figure 1. A suitable screen 36 comprises an EC Bauer "Micrasieve" equipped with a sieve of 100 microns.

The centrifugation stage 42 processes the inlet stream 41 to provide an acceptance current 43 of the centrifugation stage 42 and a reject current 44 of the centrifugation stage 42. The acceptance current 43 leaves the side of the upper flow of the cyclone Hydraulic and reject current 44 leaves the lower flow side (the tip of the hydraulic cyclone). When the process illustrated in Figure 1 is tested according to the present invention, the normalized roughness of the fibers in the acceptance stream 43 is at least 3%, and preferably at least 10% less than the fibers in the reject stream 44 of the centrifugation step 42. The process illustrated in Figure 1 can be operated to provide an acceptance stream 43 comprising the preferred cellulose pulps for the present invention. Acceptance stream 43 comprising the cellulose pulps of the present invention includes at least 10% softwood fibers, has an increase surface area of less than 0.085mm2, and has a roughness related to the average fiber length by the algebraic expression described above. The average fiber length of the acceptance stream 43 is preferably from about 0.70 mm to about 1.1. mm, and more preferably about 0.75 mm. at approximately 0.95 mm. to provide this roughness to the ratio of the length of the fiber. The weight of the fiber of the acceptance stream 43 of the centrifugation step 42 should be between about 30 to 70% of the fiber weight of the inlet stream 41 to the centrifugation step 42 such that there is approximately 30 a 70% mass separation of the fibers entering the centrifugation stage 42 between the acceptance current 43 and the rejection current 44, respectively. Such mass separation is desirable to ensure that the centrifugation step 42 provides an acceptance current 43 having a reduced roughness normalized in relation to the reject stream 44, instead of only operating to remove debris such as knots and chips. the inlet stream 41. Figure 2 is a flow chart illustrating another arrangement that can be used to reduce preferred cellulose pulps for use in the toilet papers of the present invention. In this arrangement, the centrifugation stage is performed first, followed by the length classification stage. In Figure 2, an aqueous suspension 21 comprising wood pulp fibers is first directed to form an inlet stream to the centrifugation stage 52. The centrifugation step 52 comprises at least one hydraulic cyclone. The centrifugation step processes the input stream to provide an acceptance current 53 of the centrifugation stage 52 and a reject current 54 of the centrifugation stage 52. The acceptance current 53 is output on the upper side of the hydraulic cyclone, and the reject current exits on the lower flow side (the tip of the hydraulic cyclone). When operating according to the present invention, the normalized roughness of the fibers in the acceptance stream 53 is at least 3%, and preferably at least 10% less than that of the fibers in the reject stream 54 of the centrifugation stage 52, and the average length of the fiber in the fibers in the acceptance stream 53 is preferably approximately equal to or greater than that of the suspension 21. At least a portion of the acceptance stream 53 of the centrifugation step 52 is directed to providing an input stream 61 to a length sorting stage 62. The length sorting stage 62 may comprise a screen such as the centrifugal screen described above. It may be desirable to adjust the consistency of the input stream 61 before processing the input stream 61 in the length sorting stage 62. For example, if it is desired to remove the water from the inlet stream 62 to increase its consistency, a suitable screen 60 can be placed intermediate to the centrifugation stage 52 if it is desirable to remove the water from the inlet stream 61 to increase its consistency, a suitable screen 60 can be placed intermediate to the centrifugation stage 52 and to the classification step of length 62 as illustrated in Figure 2. A suitable screen 60 comprises a CE Bauer "Micrasieve" equipped with a sieve of 100 microns. The length sorting stage 62 processes the input current 61 to provide an acceptance current 63 of the length sorting stage and a rejecting current 64 of the length sorting stage. The reject stream 64 comprises fibers having an average fiber length exceeding that of the fibers in the acceptance stream 63. The average length of the fiber is at least 20% less and preferably at least 30% less than the length fiber average of the reject stream 64 to the length classification stage. The process described in Figure 2 can be operated by providing an acceptance current 63 comprising the preferred cellulose pulps for the present invention. The acceptance stream 63 comprises the cellulose pulps of the present invention include at least 10% softwood fibers, have an incremental surface area of less than 0.085 mm2 and have a roughness related to the average fiber length by the algebraic expression cited above. The average fiber length of the acceptance stream 63 is preferably from about 0.07 mm to about 1.1 mm. , and more preferably of about 0.75 mm. at approximately 0.95 mm. to provide the aforementioned asperity to the fiber length ratio. The operating parameters of the length and centrifugation classification stages can be adjusted by the specific characteristics of the fibers contained in the suspension 21, in order to achieve the necessary change and the average fiber length and normalized roughness respectively required by the present invention. For the embodiment wherein the length classification stage comprises a centrifugal sieve, such operating parameters include the consistency of the inlet and outlet suspension, the size, shape and density of perforations in the sieving medium.; the speed at which the sifter button rotates; and the flow velocities of the input in each of the output currents. It may also be desirable to use dilution water to inflate in the removal of the reject current from the longer fibers of the screen in the screen 60, if it tends to be excessively expanded by the action of the screen. For the embodiment wherein the centrifugation stage comprises a hydraulic cyclone, examples of the operating parameters include the consistency of the inlet stream, the diameter of the cone, the angle of the cone, the size of the lower flow opening, and the Pressure drop of the entrance suspension to each leg of the exit.

E. TREATMENT OF FIBER WITH CHEMICAL SOFTENER The present invention requires that the cellulose fibers possess a reduced coefficient of friction achieved via the addition of a chemical softener. The preferred method of adding chemical softener to cellulose fibers is to add the softener to an aqueous suspension of papermaking fibers, or to supply, at the wet end of the machine to make paper at some suitable point in front of the fourdrinier wire. or of the sheet formation stage. However, because the chemical softeners within the scope of this invention are expressively substantive to the fibers, the applications of the chemical softeners prior to the process for making paper, for example by adding to aqueous pulp mixtures formed during pulp production they are also anticipated. In addition, the application of the chemical softener subsequent to the formation of the woven web, including points before, during, or after drying may also be designated to meet the requirements of the invention and are expressly included within its scope. The following examples illustrate the practice of this invention but are not intended to limit the same.

EXAMPLE 1 This example illustrates the preparation of a toilet paper product of a sheet using a recycled fiber source normally considered to be inferior to making this type of product. The types of cellulose fibers used in the preparation are: Northern Hardwood Kraft Pulp (NSK), hardwood kraft pulp of eucalyptus and a recycled commercial pulp, obtained from Oshkosh Ponderosa Fibers, Wisconsin Mill. The virgin Kraft pulps are used as delivered, while the Ponderosa pulp is pretreated forming an aqueous suspension and subjecting it to a sequential treatment in a centrifugal sieve from which a fraction of the short fiber is acquired, which is then passed through a hydraulic cyclone, from which the upper flow or acceptance fraction is captured. Screening acceptances are approximately 25% of the fed material and have a fiber length of approximately 50% less than that of the starting pulp. A simple step is taken through the cyclones at approximately 75 PSI of pressure drop from the entrance to acceptance and 0.1% solids in the feed. Acceptance of conformity comprises approximately 50% of the fibers that are fed to them. This stage is known from previous work resulting in a fiber with exceptionally low roughness as a function of its fiber length. Although highly useful in reducing the negative effects of recycled fiber, the above fractionation treatment is known to be only effective in permitted uses of recycled fibers as a partial component of soft paper products. To allow even the highest inclusion of the recycled fibers, the resulting paper product is formed in such a way "as in accordance with the practice of the present invention. Papermaking is done in a pilot-scale Fourdrinier papermaking machine. This papermaking machine is operated with sufficient purge of the wastewater to ensure that no essentially non-substantive additive will remain in the paper web after draining over the forming wire.

First, a 1% solution of a quaternary salt (dihydrogenated tallow of dimethyl ammonium methyl sulfate), obtained from Witco Chemical Company of Dublin, OH, is prepared. To assist in the preparation of this solution, an equivalent amount of polyethylene glycol of molecular weight 400 is optionally included. The quaternary salt with the PEG optionally added, are first heated to 150 ° F, then added to the water at approximately the same temperature, while being stirred Water. The head of the paper making machine is equipped with separating sheets so that long NSK fibers and shorter or recycled eucalyptus fibers can be placed in separate layers to deposit each type of fiber at its optimum location. This type of formations is common and has been recognized as such by those skilled in the art. Two comparative paper structures were formed. The first is formed by directing 20% of the weight of the sheet as NSK towards the central layer of a 3-layer composite, wherein the outer layers are comprised exclusively of the eucalyptus pulp. The second is formed by directing 20% of the weight of the sheet as NSK towards the central layer of a 3-layer composite wherein the outer layer following the forming wire is comprised exclusively of the recycled pre-treated pulp, and the other outer layer is comprised of of a mixture of the pre-treated pulp recycled with eucalyptus in a ratio of 3: 5 by weight. The total content of the recycled pulp is therefore 55%. Otherwise, the training is completed in a similar way in the two supplies. When the structure comprised of the recycled pulp is formed, the quaternary salt is added to the raw materials during the approach flow when its consistencies are approximately 3%. The quaternary salt is provided so that the ratio added to the wire side supply is twice that of the fed side supply. No quaternary salts are added to the NSK. The amount of quaternary salt added is sufficient to retain 0.105% in the finished product. The only other change needed in the process when using the recycled fibers, is a light refinement of the NSK to compensate for some resistance losses. Already «that the compound or mixed roughness of this product is known to be in excess of 11.0 and the level of treatment with the quaternary salt is sufficient to result in a reduction of the coefficient of friction (CORF) of more than 4%, the product made in accordance with this example meets the requirements projected by this invention. Confirmation is gained when the product containing the recycled fibers is judged softer by a panel of expert judges in softness.

EXAMPLE 2 This example illustrates the preparation of a single-ply bath paper product that uses a thermo-mechanical chemical fiber source normally considered to be inferior to make this type of product. The types of cellulosic fibers used in the preparation are: Northern softwood kraf pulp (NSK), eucalyptus hardwood kraft pulp and a commercial hardwood CTMP pulp, designated as 86 brightness / 350 freeness by the manufacturer which is the company Quesnel River Pulp and Paper. All the pulps are used as delivered and the resulting paper product is formed so as to conform to the practice of the present invention. Paper making is done on a pilot scale Fourdrinier paper making machine. This paper making machine is operated with sufficient water purge so that no essentially non-substantive additive will remain in the paper web after draining over the forming wire. First, a 1% solution of a quaternary salt (dihydrogenated tallow of dimethyl ammonium chloride)), obtained from Witco Chemical Company of Dublin, OH, is prepared. To assist in the preparation of this solution, an equivalent amount of polyethylene glycol of molecular weight 400 is optionally included. The quaternary salt with the PEG optionally added, are first heated to 185 ° F, then added to the water at about the same temperature, while the water is being stirred. The head of the paper making machine is equipped with separating sheets so that long NSK fibers and shorter or recycled eucalyptus fibers can be placed in separate layers to deposit each type of fiber at its optimum location. This type of formations is common and has been recognized as such by those skilled in the art. Two comparative paper structures were formed. The first is formed by directing 20% of the weight of the sheet as NSK in the central layer of a 3-layer composite, wherein the outer layers are comprised exclusively of the eucalyptus pulp. The second is formed by directing 20% of the weight of the sheet as NSK in the central layer of a 3-layer composite wherein the outer layers are supplied by a supply comprising a mixture of eucalyptus and CTMP in proportions of 7: 4. The total content of the CTMP pulp is therefore 28%. Otherwise, the training is completed in a similar way in the two supplies. When the structure comprised of the CTMP pulp is formed, the quaternary salt is added to the raw materials during the approach flow when their consistencies are about 3%. The quaternary salt is provided so that the ratio added to the wire side supply is half the feed side supply. No quaternary salts are added to the NSK. The amount of quaternary salt added is sufficient to retain 0.325% in the finished product. The only other change. Already «that the composite or mixed roughness of this product is known to be in excess of 11.0 and the level of treatment with the quaternary salt is sufficient to result in a reduction of the coefficient of friction (CORF) of more than 10%, the product made in accordance with this example meets the requirements projected by this invention. Confirmation is gained when the product containing the CTMP fibers is judged softer by a panel of expert judges in softness.

Claims (10)

1. A soft toilet paper characterized in that it comprises chemically hardened cellulose fibers, said cellulose fibers comprised of a sufficient amount of coarse fibers to raise the average mixed harshness of the toilet paper to more than about 11.0 mg / 100m, preferably greater than 12 mg / / 100m, where said cellulose fibers have a reduced coefficient of friction (CORF), in percentage points, related to their average mixed roughness (C), in mg / lOOm, by the equation: CORF > 4.27 * C-44.23 wherein said toilet paper has a specific tensile strength between about 9 and about 25 g / inch / g / m2, preferably between 11 and 17 g / in / g / m2, and a density between 0.05 and 0.20 gr / cm3, preferably between 0.08 and 0.15 gr / cm3.

2. The toilet paper according to claim 1, further characterized by "that said cellulose fibers have an average mixed fiber length between 1 mm and 1.5 mm.

The toilet paper according to claim 1 or 2, further characterized in that said cellulose fibers comprise at least 10% of fibers recycled from coarse or rough fibers of cellulose, chemical-ermomechanical fibers and mixtures thereof.

4. The toilet paper according to any of claims 1 to 3, further characterized in that said toilet paper comprises a single sheet, said sheet comprised of three superimposed layers, an inner layer and two outer layers, said inner layer being located between said two layers external, wherein said inner layer comprises cellulose fibers with an average length of heavy length of at least 1 mm, and wherein each of said two outer layers comprises fibers with an average length of heavy length less than 1 m.

The toilet paper according to any of claims 1 to 4, further characterized in that said toilet paper is densified with a pattern, such that areas of relatively high density are dispersed within a high volume field.

The toilet paper according to any of claims 1 to 5, further characterized in that said cellulose fibers are chemically softened with a quaternary ammonium compound having the formula: wherein each substituent of R2 is a hydroxyalkyl alkylamino group of C, -C6, or mixtures thereof; each R substituent is a hydrocarbyl group of CH-C22, or mixtures thereof; and X 'is compatible anion.

7. The toilet paper according to any of claims 1 to 5, further characterized in that said cellulose fibers are chemically softened with a biodegradable compound of quaternary amine ester having the formula: wherein each R is a C13-C, 9 aliphatic hydrocarbyl group or mixture thereof; R. is an alkyl or hydroxyalkyl group of C, -C6 or mixture thereof; and X "is compatible anion

8. The toilet paper according to any of claims 1 to 5, further characterized in that said cellulose fibers are" chemically softened with a polysiloxane compound. "9. The toilet paper according to any of claims 1 to 5, further characterized in that said cellulose fibers are chemically softened with a softener selected from sorbitan esters, ethoxylated sorbitan esters, propoxylated sorbitan esters, mixed ethoxylated / propoxylated sorbitan esters, and mixtures thereof. The toilet paper according to any of claims 1 to 9, further characterized in that said cellulose fibers comprise from 0.05% to 2.0% by weight of a chemical softener.