MXPA98002913A - Method for making tissues sua - Google Patents

Abstract

The present invention is generally directed to facial tissues that have great softness and strength. Facial tisues are made of a multi-layer paper fabric containing a middle layer of eucalyptus fibers either alone or in combination with polyester fibers. The paper web is made with a debonding agent to produce a fabric having reduced levels of fiber bonding. Once formed, the paper web is treated on each side with a binding agent in a preselected pattern. Both sides of the paper web are also creped. In order to create a smooth low friction surface, the paper web is fed through a calendering machine and treated with a friction reducing composition and subsequently dried.

Description

METHOD FOR MAKING SMOOTH TISSUES Field of the Invention The present invention is generally directed to a method for producing a single-layer ultra-smooth facial tissue. More particularly, the present invention is directed to a single stratum soft facial tissue containing a middle layer of eucalyptus fibers. The tissue product is made by applying a latex binding agent and creping each side of the paper web. In order to reduce the surface friction of the fabric, the paper web is then calendered and an agent is applied against friction.

Background of the Invention Absorbent paper products such as paper towels, facial tissue and other similar products are designed to include several important properties. For example, the products should have a good volume, a soft feel and should be highly absorbent. The product must also have a good resistance even when wet and must resist tearing. Unfortunately, it is very difficult to produce a high strength paper product that is also soft and highly absorbent. Usually, when steps are taken to increase a product's property, other characteristics of that product are adversely affected. For example, softness is typically increased by decreasing or reducing the fiber bond within the paper product. By inhibiting or reducing the fiber bond, however, the strength of the paper web is adversely affected.

A particular process that has proved to be very successful in the production of paper towels in the cleaners is described in United States Patent No. 3,879,257 issued to Gentile, et al., Which is incorporated herein by reference in its entirety. In the Gentile patent, and others, a process is described in which a bonding material is applied in a spaced and thin separate pattern on one side of a fibrous web. The fabric is then adhered to a creping surface and creped from the surface. A bonding material is applied to the opposite side of the fabric and the fabric is similarly creped. The process described in Gentile and others produces cleansing products having an exceptional volume, an extraordinary softness and good absorbency. The surface regions of the fabric can also provide excellent strength, resistance to abrasion, and dry cleaning properties.

Although Gentile et al. Describes a method for producing paper towels with improved properties, the process has not been found particularly well suited for producing facial tissues up to now. In comparison to the products manufactured in Gentile and others, facial tis should have a much softer feel. In fact, since one of the primary uses of facial tissues is for application to the face of the individual, softness is perhaps the most important feature of the product.

In addition to lacking softness, products made according to Gentile and others are also generally too rough or too rough to be used as facial tissue. Again, because the facial tissues are placed in contact with the face of a user, the tissue must have a low friction and smooth surface.

Although the process described in Gentile et al. Was not specifically directed to the production of facial tissues, it would nevertheless be particularly advantageous if particular aspects of the teachings described in Gentile et al. Could be incorporated into the methods for producing facial tissues. For example, the method described in Gentile et al. Has been proven to be effective in increasing the strength and absorbency of cleaner products. It would therefore be particularly desirable if the particular aspects of Gentile and others could be used to produce low friction facial tissues having improved wet and dry strength characteristics, strength properties, and tear resistant properties.

Synthesis of the Invention The present invention recognizes and refers to the above disadvantages, and to the deficiencies of the constructions and methods of the prior art.

Therefore, it is an object of the present invention to provide an improved process for producing facial tissues.

Another object of the present invention is to provide a method for producing facial tissues that are soft and have a low friction surface.

Another object of the present invention is to provide a method for producing soft facial tissues having a high dry strength, a high wet strength and which are resistant to tearing.

Another object of the present invention is to provide a method for producing facial tissues that are resistant to fluff release and that do not produce significant amounts of lint during use.

Still another object of the present invention is to provide a method for producing facial tissues incorporating soft eucalyptus fibers placed in sandwich form between two outer layers of soft wood fibers.

It is another object of the present invention to provide a method for producing facial tissues by applying a bonding agent to both sides of a paper web in a preselected pattern and to creping each side of the fabric.

It is another object of the present invention to provide a method for producing a facial tissue which involves calendering a double creped paper web and then applying a non-fugitive antifriction agent to the fabric.

These and other objects of the present invention are achieved by providing a method for producing a single stratum soft tissue. The method includes the steps of providing a paper web including a middle layer containing eucalyptus fibers. The middle layer is surrounded by a disbonded first outer layer containing soft wood fibers and a second disengaged outer layer also containing soft wood fibers.

A first bonding agent is applied to a first side of the fabric in a preselected pattern. The first side of the fabric is then adhered to a first creping surface and creped. Similarly, a second bonding agent is applied to the second side of the fabric in a preselected pattern and adheres to a second creping surface. The second side of the fabric is then creped from a second creping surface.

The method further includes the step of applying a friction reducing agent to at least one side of the paper web. For example, in one embodiment, the friction reducing agent comprises a quaternary silicone composition. The silicone composition can be added to the fabric in an amount of from about 0.4 percent to about 2 percent by weight.

According to the present invention, in order to inhibit the bonding of the interfiber during the formation of the paper web, a debonding agent can be added to the fiber solution used to make the fabric. The debonding agent can be added in an amount of from about 0.2 percent to about 1 percent by weight based on the total weight of the fibers contained in the fabric.

In a preferred embodiment, the paper web also includes short polyester fibers contained in the middle layer combined with the eucalyptus fibers. The polyester fibers can also be added to the paper web in an amount of from about 5 percent to about 20 percent by weight.

The first binding agent and the second binding agent that are applied to each side of the paper web can be applied in a pattern that covers from about 30 percent to about 60 percent, and more particularly from about 40 percent. cent to about 50 percent of the surface area of each side. The binding agent can be applied to each side of the paper web in a combined amount of from about 4 percent to about 7 percent by weight. Once applied, each of the binding agents can penetrate the fabric in an amount of from about 25 percent to about 40 percent of the total thickness of the fabric.

The preselected pattern used to apply the binding agents may be, in one embodiment, a lattice interconnected design. Alternatively, the preselected pattern may comprise a succession of discrete points. In a preferred embodiment, the first binding agent and the second binding agent comprise an ethylene vinyl acetate copolymer degraded with N-methyl acrylamide groups. Vinyl acrylic copolymers with degradation capacity are also useful.

Before adding the friction reducing agent, the method of the present invention can further include the step of calendering the paper web. The calendering of the paper web softens the surface of the fabric to reduce the roughness and to facilitate the application of the friction reducing agent.

Once formed, the single stratum soft tissue of the present invention can have a basis weight of from about 20 to about 25 pounds per ream. In addition to being soft, the tissues made according to the present invention are also very strong and stretchable. For example, in one embodiment the tissue has a moisture resistance of at least 5 ounces in the transverse direction.

These and other objects of the present invention are achieved by providing, in a preferred embodiment, a method for producing tissues comprising the steps of first providing a previously creped three-ply paper web. The paper web includes a middle layer containing a mixture of eucalyptus and polyester fibers surrounded by a first outer layer containing softwood fibers and a second outer layer also containing softwood fibers. The paper web includes a debonding agent added during the formation of the fabric.

A binding agent is applied in a preselected pattern on each side of the fabric. More particularly, the binding agent is added in an amount that covers from about 40 percent to about 50 percent of the surface area of each side of the fabric. The binding agent is added to each side of the fabric in an amount of from about 2 percent to about 3.5 percent by weight.

Each side of the paper web is creped from a creping surface after the binding agent is applied. After creping both sides of the fabric, the fabric is calendered to increase the smoothness of the surfaces. A friction reducing agent is then applied by spraying or printing to at least one side of the fabric. The friction reducing agent can be, for example, a water dispersion of a quaternary silicone which, when dried, does something substantive to the cellulose surface.

Other objects, features and aspects of the present invention are discussed in more detail below.

Brief Description of the Drawings A total and enabling description of the present invention, including the best mode for a person with ordinary skill in the art, is set forth more particularly in the remainder of the description, including reference to the accompanying figures in which: Figure 1 is a schematic diagram of a paper fabric forming machine, illustrating the formation of a paper web having multiple layers according to the present invention.

Figure 2 is a schematic diagram of a paper fabric forming machine that crepes one side of the fabric.

Figure 3 is a schematic diagram of an equipment of a system for double creping a paper web according to the present invention.

Figure 4 is a schematic diagram of one embodiment of a system for calendering and applying a friction reducing agent to a paper web according to the present invention; Y Figure 5 is a schematic diagram of an alternative embodiment of a system for calendering and applying a friction reducing agent to a paper web according to the present invention.

The repeated use of reference characters in the present description and drawings is intended to represent the same features or elements or features or analogous elements of the present invention.

Detailed Description of Preferred Additions It will be understood by one of ordinary skill in the art that the present discussion is a description of example modalities only, and that no attempt is made to limit the broader aspects of the present invention, the broader aspects of which are incorporated into the construction. of example.

In general, the present invention is directed to a process for producing facial tissues having greater softness characteristics and having smooth and low friction surfaces. In addition to being smooth and smooth, the facial tissues also have high strength values in either wet or dry. In addition, the tissues have good stretch characteristics, are tear resistant, and do not produce a substantial amount of waste when used.

The process of the present invention generally involves applying a binding agent and creping both sides of a paper web. The binding agent is applied in a preselected pattern to provide strength and stretchability without adversely affecting the smoothness of the sheet. Once creped on both sides, in order to create a low-friction tissue, the paper web is calendered. After calendering, an antifriction agent can also be applied to the fabric. Preferably, the antifriction agent binds with the cellulosic fibers and does not transfer to the user's face when in use.

The facial tissues made according to the present invention are produced from a multi-layer paper web. More particularly, the tissues are made from a stratified pulp supply having three main layers. According to the present invention, the middle layer of the paper web contains eucalyptus fibers.

Eucalyptus fibers, which are typically from about 0.8 to 1.2 millimeters in length, provide uniform formation and greatly increase the softness of the fabric. Eucalyptus fibers also improve the brilliance and increase the opacity of the paper. In addition, the eucalyptus fibers change the pore structure of the paper, greatly increasing the transmission ability of the paper web. By placing the eucalyptus fibers in the middle of the fabric, the moisture that makes contact with the surface of the fabric is pulled into the center.

Unfortunately, incorporating the eucalyptus fibers into the paper web increases the production of lint or lint. According to the present invention, however, the lint or lint released from the tissue is minimized by placing the layer of eucalyptus fibers between the outer layers made of other types of fibers. For example, the outer layers of the paper web can be made of fibers that are generally longer than the eucalyptus fibers. For example, in one embodiment, northern softwood kraft fibers can be used to form the outer layers. Northern softwood kraft fibers have a fiber length of about 1.8 millimeters to about 2.5 millimeters. These particular fibers not only prevent the leakage of lint from the center of the paper web, but also improve the strength of the fabric.

The amount of eucalyptus fibers incorporated within the paper web of the present invention can be from about 10 percent to about 35 percent by weight, based on the total weight of the fabric. The rest of the fabric may comprise the outer layers of soft wood fibers. In a preferred embodiment, however, the polyester fibers having a length of about 5 millimeters can be added to the core layer and combined with the eucalyptus fibers in an amount of from about 5 percent to about 20 percent by weight. weight based on the total weight of the fabric. Adding the polyester fibers to the middle layer increases the strength, softness and whiteness of the fabric.

The multi-layer base fabric according to the process of the present invention should be formed without a substantial amount of the inner fiber to the fiber-bonding strength. In this aspect, the fiber supply used to form the base fabric can be treated with a chemical release agent. The debonding agent can be added to the fiber solution during the pulping process or added directly to the headbox. Suitable dissociating agents that can be used in the present invention include cationic stripping agents such as alkyl quaternary fatty alkyl salts, mono alkyl tertiary amine salts, primary amine salts, quaternary imidazolino salts, salt silicone quaternary and unsaturated fatty alkyl amine salts. Other suitable debonding agents are described in U.S. Patent No. 5,529,665 issued to Kaun which is incorporated herein by reference. In particular, Kaun describes the use of silicone compositions as dissociating agents.

In a preferred embodiment, the stripping agent used in the process of the present invention is an organic quaternary ammonium chloride and particularly a silicone-based amine salt of a quaternary ammonium chloride. In this aspect, the stripping agent can be added to the fiber solution in an amount of from about 0.2 percent to about 1 percent by weight, based on the total weight of the fibers present within the solution.

Referring to Figure 1, one embodiment of a device for forming a multilayer stratified pulp supply is illustrated. As shown, a generally three-layer head box 10 includes an upper head box wall 12 and a lower head box wall 14. The head box 10 further includes a first divider 16 and a second divider 18, which separate three fiber supplies.

Each of the fiber layers comprises a dilute aqueous suspension of papermaking fibers. In accordance with the present invention, as described above, the middle layer 20 contains eucalyptus fibers either alone or in combination with the polyester fibers. The outer layers 22 and 24, on the other hand, contain softwood fibers, such as softwood kraft from the north.

An endlessly moving forming fabric 26, suitably supported and driven by the rollers 28 and 30, receives the supply for making layered paper coming out of the head box 10. Once retained on the fabric 26, the fiber suspension in Water passes through the fabric as shown by arrows 32. Water removal is achieved by combinations of gravity, centrifugal force and suction with vacuum depending on the forming configuration.

Multilayer paper webs are also described and discussed in U.S. Patent No. 5,129,988 issued to Farrinaton Jr. and in U.S. Patent No. 5,494,554 to Edwards, and others, both of which are incorporated herein by reference.

Referring to Figure 2, one embodiment of a paper machine is illustrated capable of receiving the layered fiber suspension of the head box 10 and forming a paper web for use in the process of the present invention. As shown, in this embodiment, the forming fabric 26 is supported and propelled by a plurality of guide rollers 34. A vacuum box 36 is positioned below the forming fabric 26 and adapted to remove water from the fiber supply, to help in the formation of a fabric.

From the forming fabric 26, a formed fabric 38 is transferred to a second fabric 40, which can be either a wire or a felt. The fabric 40 is supported to move about a continuous path by means of a plurality of guide rollers 42. A pickup roller 44 designed to facilitate the transfer of the fabric 38 from the fabric 26 to the fabric 40 is also included. Preferably , the speed at which the fabric 40 is carried is approximately the same speed at which the fabric 26 is driven so that the movement of the fabric 38 through the system is consistent.

From the fabric 40, the cloth or fabric 38, in this embodiment, is transferred to the surface of a rotary heated dryer drum 46, such as a Yankee dryer. The fabric 38 is compressed slightly in contact with the surface of the dryer drum 46 to which it adheres, due to its moisture content and its preference for the smoothness of the two surfaces. In some cases, however, a creping adhesive, such as ethylene vinyl acetate, may be applied on the cloth surface or the drum surface to facilitate attachment of the cloth to the drum.

As the fabric 38 is carried through a portion of the rotational path of the dryer surface, heat is imparted to the fabric causing most of the moisture contained within the fabric to evaporate. The fabric 36 is then removed from the dryer drum 46 by a creping blade 48. Although optional, the creping fabric 38 as formed further reduces the internal bond within the fabric and increases softness.

In an alternate embodiment, the fabric 38 can be completely dried before being creped. A continuous drying dryer achieves the removal of moisture from the fabric by passing air through the fabric without applying any mechanical pressure. Continuous drying can increase the volume and softness of the fabric.

The paper web formed from the process illustrated in Figure 2 has certain physical characteristics that are particularly advantageous for use in the remainder of the process of the present invention. In particular, the paper web 38 is characterized by having a reduced amount of an inner fiber bond strength. As described above, the fabric also contains eucalyptus fibers. The low bond strength in combination with the eucalyptus fibers provides softness, volume, absorbency, opacity, transmission ability and brilliance. As will be described hereafter, the remainder of the process of the present invention is designed not only to improve the aforementioned properties but also to provide the paper web with strength and stretchability.

Once the paper web 38 is formed, a binding agent is applied to each side of the fabric and each side of the fabric is then creped. Referring to Figure 3, an embodiment of an apparatus that can be used to crepe each side of the paper web is illustrated.

As shown, the paper web 38 made according to the process illustrated in Figure 2 or according to a similar process, is passed through a first binding agent application station generally designated with the number 50. The station 50 it includes a pressure point formed by a smooth rubber press roll 52 and a patterned rotogravure roller 54. The rotogravure roller 54 is in communication with a reservoir 56 containing a first binding agent 58. The rotogravure roller 54 applies the binding agent 58 on one side of the fabric 38 in a preselected pattern.

The fabric 38 is then pressed to a contact with a first creping drum 60 by means of a press roll 62. The binding agent causes only those parts of the fabric where it is placed to adhere to the creping surface. If desired, the creping drum 60 can be heated to promote clamping between the fabric and the surface of the drum and to partially dry the fabric.

Once the creping drum 60 is adhered, the fabric 38 is brought into contact with a creping blade 64. Specifically, the fabric 38 is removed from the creping roller 60 by the action of the creping blade 64, carrying out a first crepe pattern controlled on the fabric.

Once creped, the fabric 38 can be advanced by the pull-down rollers 66 to a second binding agent application station designated with the number 68. The station 68 includes a transfer rollers 70 in contact with a rotogravure roller 72, the which is in communication with a reservoir 74 containing a second binding agent 76. Similar to station 50, the second binding agent 76 is applied to the opposite side of the fabric 38 in a preselected pattern. Once the second binding agent is applied, the fabric 38 is adhered to a second creping roll 78 by means of a press roll 80. The fabric 38 is carried on the creping drum surface 78 by a distance and then removes from it by the action of a second creping blade 82. The second creping blade 82 performs a second creping operation with controlled pattern on the second side of the paper web.

Once creped for a second time, the paper web 38 in this embodiment is pulled through a drying or curing station 8. The drying station 84 can include any form of a heating unit, such as an oven energized by infrared heat, microwave energy, hot air or the like. The drying station 84 may be necessary in some applications to dry the fabric and / or cure the first and second bonding agents. Depending on the selected bonding agents, however, in other applications the drying station 84 may not be necessary.

Once pulled through the dryer station 84, the fabric 38 can be wound onto a roll of material 86 for further processing according to the present invention, as shown in Figure 4. Alternatively, however, the fabric 38 can be supplied directly inside the additional processing stations.

The bonding agents applied to each side of the paper web 38 are selected not only to help crepe the fabric but also to add dry strength, wet strength, stretchability, and tear resistance to the paper. The binding agents also prevent the lint or lint from escaping from the tissue during use.

The binding agent is applied to the base fabric as described above in a preselected pattern. In one embodiment, for example, the binding agent can be applied to the fabric in a cross-linked pattern, such that the pattern is interconnected forming a network-type design on the surface.

In an alternate preferred embodiment, however, the binding agent is applied to the fabric in a pattern representing a succession of boat-shaped dots. The application of the binding agent in discrete forms, such as dots, provides sufficient strength to the fabric without covering a substantial part of the surface area of the fabric.

In particular, the bonding agents adversely affect the absorbency of the fabric. Therefore, it is preferred to minimize the amount of the binding agent applied. In comparison to conventional processes, the process of the present invention is designed to require smaller amounts of the binding agent. In this regard, the pattern applied to each side of the fabric should be compressed so that the stitches are small and arranged closely together.

Specifically, according to the present invention the binding agent is applied to each side of the paper web as to cover from about 30 percent to about 60 percent of the surface area of the fabric. More particularly, in many applications, the binding agent will cover from about 40 percent to about 50 percent of the surface area of each side of the fabric. The total amount of bonding agent applied to each side of the fabric will preferably be in the range of from about 4 percent to about 7 percent by weight, based on the total weight of the fabric. In other words, the binding agent is applied to each side of the fabric at an aggregate rate of about 2 percent to about 3.5 percent by weight.

At the amounts indicated above, the binding agent can penetrate the paper web from about 25 percent to about 40 percent of the total thickness of the fabric. In most applications, the binding agent must not penetrate over 50 percent of the fabric but should at least penetrate from about 10 percent to about 15 percent of the thickness of the fabric.

Particular binding agents that can be used in the present invention include latex compositions, such as acrylates, vinyl acetates, vinyl chlorides, and methacrylates. Some water-soluble binding agents can also be used including polyacrylamides, polyvinyl alcohols and carboxymethyl cellulose.

In a preferred embodiment, the binding agent used in the process of the present invention comprises an ethylene vinyl acetate copolymer. In particular, the ethylene vinyl acetate copolymer is preferably degraded with N-methyl acrylamide groups using an acid catalyst. Suitable acidic catalysts include ammonium chloride, citric acid, and maleic acid. The bonding agent must have a glass transition temperature of not less than 10 degrees F and not higher than + 20 degrees F.

Referring to Figure 4, the remaining processing steps according to the present invention include calendering the paper web and applying a friction reducing agent so as to provide a resultant tissue product having a low friction and smooth surface. As shown in Figure 4, the roll of material 86 formed according to the process illustrated in Figure 3 feeds the calendering machine 88. The calendering machine 88 may include two rolls, such as steel rolls, designed for making smooth the surfaces of the paper web 38. Even though the calendering machine 88 reduces to a certain extent, the volume of the paper web 38, it has been found that the calendering operation does not appreciably affect the softness of the fabric. In addition to providing a fabric with smooth surfaces, the calendering machine 88 also provides a uniform surface to facilitate the application of a friction reducing agent.

In this aspect, of the calendering machine 88, the paper web 38 is contacted with a sprinkler 90 which applies a friction reducing composition to the fabric from a reservoir 92. In addition to being sprayed on the paper web 38, The friction reducing composition can also be printed on the cloth using a lithographic printing source. The friction reducing composition can be applied to any one single side of the fabric or both sides of the fabric.

Once applied to the paper web 38, the friction reducing composition increases the softness of the fabric surface and reduces friction. Some examples of the friction reducing compositions that can be used in the process of the present invention are described in U.S. Patent No. 5,558,873 issued to Funk et al., Which is incorporated herein by reference.

In a preferred embodiment, the friction reducing composition applied is a quaternary lotion, such as a quaternary silicone spray. For example, the composition may include a quaternary ammonium silicone chloride. A disposable glycol silicone quaternary ammonium chloride suitable for use in the present invention is ABIL SW sold by Goldschmidt Chemical Company of Essen, Germany.

In an alternate embodiment, the friction reducing agent may contain antimicrobial agents to destroy the germs that come into contact with the paper web. For example, a commercially available friction reducing spray having antimicrobial properties is DOW 5700 marketed by Dow-Corning Corporation of Midland, Michigan. DOW 5700 is a silicone quaternary spray that contains antimicrobial agents. Of advantage, the DOW 5700 can also be used as a disengaging agent during the formation of the fabric. Therefore, the DOW 5700 or other similar products can also be added during the formation of the fabric.

In a further embodiment, the friction reducing agent may also include a fragrance or odor masker. The fragrance can be added to the friction reducing agent in order to mask the odor of the silicone composition or it can be added to give the resulting tissue product a desired and aesthetic aroma.

Quaternary silicone compositions are preferred friction reducing agents in the present application because they bond with the cellulosic fibers contained within the base fabric. By joining the cellulosic fibers, the composition is not transferred onto the wearer's skin when the tissue product is used. In one embodiment, the friction reducing composition is applied to one side of the paper web in an amount of from about 0.4 percent to about 2 percent by weight and particularly from about 0.4 percent to about 1.4 percent. percent by weight, based on the weight of the paper web.

After being sprayed with the friction reducing composition, the paper web 38 is fed to a dryer 94 such as an infrared dryer. The dryer 94 removes any remaining moisture within the fabric.

As shown, the fabric can then be wound onto a roll of material 96, which can be transferred to another location and cut into commercial size sheets to be packaged as a facial tissue.

Referring to Figure 5, an alternate embodiment of a process for calendering paper web 38 and applying a friction reducing agent is illustrated. As shown, in this embodiment, the paper web 38 is fed from the roll of material 86 to an application station of friction reduction and calendering agent in combination designated generally with the number 100. The station 100 includes a first calendering roll 102 which may, for example, be a smooth steel roll, and a second calender roll 104 which may be, for example, a hard rubber roll. A spray 106 sprays a friction reducing agent on the calendering roller 104 which is then evenly distributed on one side of the paper web 38. Optionally, the station 100 can further include a second sprayer 108. The sprayer 108 applies an agent friction reducer to the calendering roller 102 for application to the opposite side of the paper web 38.

In the process illustrated in Figure 5, the friction reducing agent is applied indirectly to the paper web 38 by first being sprayed onto the calendering rolls 102 and 104. In this arrangement, it has been discovered that the friction reducing agent It is applied more evenly and uniformly to the paper cloth. In particular, some friction reducing agents when applied directly to a paper web tend not to distribute evenly over the surface of the fabric. In the system illustrated in Figure 5, however, the calendering rolls 102 and 104 not only smooth the surface of the cloth 38 but also uniformly apply and distribute the friction reducing agent over the entire surface of the fabric.

From the calendering roller 104, the paper web 38 is then fed to a heated drum 110 which removes any remaining moisture within the fabric. The fabric is then rolled into a roll of material 96, which can then be cut into commercially sized sheets for packaging.

As described above, the application of the friction reducing agent to the paper web of the present invention gives the resulting paper product a softer and smoother feel. It has also been discovered, however, that the friction reducing agent also serves to prevent blockage of the sheets of paper after the tissue product has been packaged. As used herein, blocking refers to the propensity of the separate sheets of tissue to stick together due to the presence of the latex binding material. The friction reducing agent, however, appears to prevent the binding material contained in a sheet from interacting with the binding material contained on an adjacent sheet.

Facial tissues made according to the process described above provide many advantages and benefits over conventional products and methods. Facial tissues have improved facial softness, low surface friction, high moisture resistance, good tear resistance, and low lint production. The basis weight of the facial tissues made according to the present invention can be from about 20 pounds per 2,880 square feet (ream) to about 25 pounds per ream. After calendering, the ratio of volume to basis weight for the tissue is between about 10 to about 12 units of basis weight per volume. Of particular advantage, the tissues have a great softness and a moisture resistance of at least 3 ounces and particularly of at least 5 ounces in the transverse direction.

The present invention can be better understood with reference to the following Example.

E J E P L O A single stratum facial tissue was made according to the present invention and tested.

Specifically, a single stratum facial tissue having a basis weight of 21 pounds per ream was made using a fiber supply including 76 percent by weight of softwood kraft fibers from the north, 13 percent by weight of 1.5 polyester fibers. denier of a quarter of an inch, and 12 percent by weight of eucalyptus fibers. The paper web was tested in a layered manner so that the polyester fibers and the eucalyptus fibers were contained in a middle layer of the fabric. During the formation, the paper cloth was dried in a continuous form and creped moderately from a Yankee dryer.

After the paper web was formed, a bonding agent was printed on each side of the fabric and both sides of the fabric were creped similar to the process illustrated in Figure 3. The bonding agent was applied to each side of the fabric. fabric according to a pattern comprising a succession of discrete points. The binding agent used was an ethylene vinyl acetate latex.

Once the latex binding agent was applied to the fabric and the fabric was creped on each side, the fabric was then calendered and a friction reducing agent was applied. The friction reducing agent was a 0.05 percent silicone emulsion.

Six (6) samples of the facial tissue were then subjected to standardized tests regarding strength, brightness and volume. The following average results were obtained: A B Characteristics of the Single Stratus Facial Tissue The aforementioned single layer facial tissue produced according to the process of the present invention was found to have a greater softness and brilliance while also having good stretch characteristics, strength and absorbency.

These and other modifications and variations of the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various modalities can be exchanged both in whole and in part. In addition, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and that it is not intended to limit the invention thus described in such appended claims.

Claims (27)

R E I V I N D I C A C I O N S

1. A method for producing a single stratum soft tissue comprising the steps of: providing a paper web including a middle layer comprising eucalyptus fibers, a first outer layer comprising soft wood fibers and a second outer layer also comprising soft wood fibers, said paper web having a first side and a second side; applying a first binding agent to said first side of said fabric in a preselected pattern and adhering said first side of said fabric to a first creping surface; creping said first side of said fabric from the first creping surface; applying a second binding agent to said second side of said fabric in a preselected pattern and adhering said second side of said fabric to a second creping surface; creping said second side of said fabric from the second creping surface; and applying a friction reducing agent to at least one side of said paper web, said friction reducing agent comprising a quaternary silicone composition.

2. A method as claimed in clause 1 characterized in that said median layer of said paper web further comprises polyester fibers, said polyester fibers being present in an amount of from about 5 percent to about 20 percent by weight. weight of said fabric.

3. A method as claimed in clause 1 characterized in that said paper web further comprises a debonding agent, said debonding agent being added to said web in an amount of from about 0.2 percent to about 1 percent by weight based on the total weight of the fibers contained in said fabric, said debonding agent inhibits the fibers in said fabric from joining together during the formation of said paper web.

4. A method as claimed in clause 1 characterized in that said first binding agent is applied to said first side of said paper web in a pattern that covers from about 30 percent to about 60 percent of the surface area of said first side, and wherein said second binding agent is applied to said second side of the paper web in a pattern that covers from about 30 percent to about 60 percent of the surface area of the second side.

5. A method as claimed in clause 4 characterized in that said first binding agent and said second binding agent are applied to said first and second sides of said paper web in a combined amount of from about 4 percent to about 7 percent. percent by weight of said paper web.

6. A method as claimed in clause 5 characterized in that each of said first binding agent and said second binding agent penetrates from about 25 percent to about 40 percent of the total thickness of said paper web.

7. A method as claimed in clause 6 characterized in that said first binding agent and said second binding agent are applied to said paper web in a preselected pattern comprising a succession of discrete shapes.

8. A method as claimed in clause 1 characterized in that said first binding agent and said second binding agent comprise an ethylene vinyl acetate copolymer crosslinked with N-methyl acrylamide groups.

9. A method as claimed in clause 1 characterized in that it comprises the step of calendering said paper web after creping said second side of said web and before applying said friction reducing agent.

10. A method as claimed in clause 1 characterized in that said eucalyptus fibers are added to said paper web in an amount of from about 10 percent to about 35 percent by weight.

11. A single stratum facial tissue made in accordance with the process as claimed in clause 1 characterized in that said facial tissue has a basis weight of from about 20 to about 25 pounds per 2,880 square feet of fabric.

12. A method for producing a single stratum soft tissue comprising the steps of: providing a three layer paper web including a middle layer comprising eucalyptus fibers, a first outer layer comprising softwood fibers and a second outer layer also comprising softwood fibers, said paper web further comprising an aggregate debonding agent during the formation of said fabric, said paper web has a first side and a second side; applying a binding agent to said first side of said fabric in a preselected pattern, said binding agent covers from about 30 percent to about 60 percent of the surface area of said first side, said binding agent being added in an amount from about 2 percent to about 3.5 percent by weight based on the weight of said paper web, said binding agent being used to adhere said first side of said paper web to a first creping surface, - creping said first side of said fabric from said first creping surface; applying said binding agent to said second side of said fabric in a preselected pattern, said binding agent covers from about 30 percent to about 60 percent of the surface area of said second side of said fabric, said binding agent being added in an amount of from about 2 percent to about 3.5 percent by weight based on the weight of said paper web, said binding agent being used to adhere said second side of said web to a second creping surface; creping said second side of said fabric from said second creping surface; calendering said paper web; Y apply a friction reducing agent to at least one side of said paper web.

13. A method as claimed in clause 12 characterized in that said binding agent comprises an alkylene vinyl acetate copolymer.

14. A method as claimed in clause 12 characterized in that said middle layer of said paper web further comprises polyester fibers, said polyester fibers being aggregated in an amount of from about 5 percent to about 20 percent by weight. weight based on the weight of said paper web.

15. A method as claimed in clause 12 characterized in that said pre-selected pattern by which said bonding agent is applied to said first side of said fabric and said second side of said fabric comprises a secession of discrete shapes.

16. A method as claimed in clause 12 characterized in that said friction reducing agent comprises a quaternary silicone glycol composition, said friction reducing agent being added in an amount of from about 0.4 percent to about 2 percent by weight based on the weight of said paper web.

17. A method as claimed in clause 12 characterized in that said paper web that is provided has been creped before applying said binding agent.

18. A method as claimed in clause 12 characterized in that said agent penetrates from about 25 percent to about 40 percent of the thickness of said paper web.

19. A method as claimed in clause 12 characterized in that said single stratum soft tissue has a basis weight of from about 20 to about 25 pounds per 2,880 square feet and has a moisture resistance of at least 3. ounces in the transverse direction.

20. A method as claimed in clause 12 characterized in that said eucalyptus fibers are present in said paper web in an amount of from about 10 percent to about 35 percent by weight.

21. A method for producing a single stratum soft tissue comprising the steps of: providing a pre-creped three-ply paper web including a middle layer comprising a mixture of eucalyptus and polyester fibers, a first outer layer comprising soft wood fibers and a second outer layer also comprising soft wood fibers, said web of paper includes an aggregate stripping agent during the formation of said web, said web has a first side and a second side; applying a binding agent in a preselected pattern, said binding agent covers from about 40 percent to about 50 percent of the area of said first side of said fabric, said binding agent being added in an amount of from about 2 percent. one hundred to about 3.5 weight percent based on the weight of said paper web, said bonding agent being used to adhere said first side of said paper web to a first creping surface; creping said first side of said fabric from said first creping surface; applying said binding agent to said second side of said fabric in a preselected pattern, said bonding agent covering from about 40 percent to about 50 percent of the surface area of said second side of said fabric, said binding agent being added in an amount of from about 2 percent to about 3.5 percent by weight based on the weight of said paper web, said binding agent being used to adhere said second side of said web to a second creping surface; creping said second side of said fabric from said second creping surface; calendering said paper web; applying to the at least one side of said paper web a friction reducing agent comprising a quaternary silicone composition; Y wherein said single stratum soft tissue has a basis weight of from about 20 to about 25 pounds per 2,880 square feet.

22. A method as claimed in clause 21 characterized in that said friction reducing agent is added in an amount of from about 0.4 percent to about 2 percent by weight based on the weight of the paper web

23. A soft tissue of single stratum produced according to the process as claimed in clause 21.

24. A method as claimed in clause 21 characterized in that said binding agent is applied to said first side and said second side of said paper web in a preselected pattern comprising a succession of discrete sheets.

25. A method as claimed in clause 21 characterized in that said friction reducing agent contains an antimicrobial agent.

26. A method as claimed in clause 21 characterized in that said eucalyptus fibers are present within said paper web in an amount of from about 10 percent to about 35 percent by weight.

27. A method as claimed in clause 21 characterized in that said friction reducing agent is applied indirectly to at least one side of said paper web. 28 A method as claimed in clause 21 characterized in that said friction reducing agent contains a fragrance. SUMMARY The present invention is generally directed to facial tissues that have great softness and strength. The facial tissues are made of a multi-layer paper fabric containing a middle layer of eucalyptus fibers either alone or in combination with polyester fibers. The paper web is made with a debonding agent to produce a fabric having reduced levels of fiber bonding. Once formed, the paper web is treated on each side with a binding agent in a preselected pattern. Both sides of the paper web are also creped. In order to create a smooth low friction surface, the paper web is fed through a calendering machine and treated with a friction reducing composition and subsequently dried.