MX2008007532A

MX2008007532A - Tissue products containing a polymer dispersion

Info

Publication number: MX2008007532A
Application number: MXMX/A/2008/007532A
Authority: MX
Inventors: M Runge Troy; R Lostocco Michael; Joseph Dyer Thomas; Nickel Deborah
Original assignee: Kimberlyclark Worldwide Inc
Priority date: 2005-12-15
Filing date: 2008-06-11
Publication date: 2008-09-02

Abstract

Tissue products are disclosed containing an additive composition. The additivecomposition, for instance, comprises an aqueous dispersion containing an olefinpolymer, an ethylene-carboxylic acid copolymer, or mixtures thereof. The olefinpolymer may comprise an interpolymer of ethylene and octene, while the ethylene-carboxylicacid copolymer may comprise ethylene-acrylic acid copolymer. The additivecomposition may also contain a dispersing agent, such as a fatty acid. The additivecomposition may be incorporated into the tissue web by being combined with thefibers that are used to form the web. Alternatively, the additive compositionmay be topically applied to the web after the web has been formed. For instance,in one embodiment, the additive composition may be applied to the web as a crepingadhesive during a creping operation. The additive composition may improve thestrength of the tissue web without substantially affecting the perceived softnessof the web in an adverse manner.

Description

TISU PRODUCTS CONTAINING A POLYMER DISPERSION BACKGROUND OF THE INVENTION Absorbent tissue products such as paper towels, facial tissue, bath tissue and other similar products are designed to include several important properties. For example, the products could have good volume, a soft feeling and be highly absorbent. The product could also have good strength and tear resistant, even while wet. Unfortunately, it is very difficult to produce a high strength tissue product that is also soft and highly absorbent. Usually, when steps are taken to increase a property of the product, other characteristics of the product are adversely affected.

For example, the softness is typically increased by decreasing or reducing the cellulose fiber bond within the tissue product. Inhibiting or reducing the bonding of fibers, however, adversely affect the resistance of the tissue tissue.

In other embodiments, the softness is enhanced by the topical addition of a softening agent to the outer surfaces of the tissue tissue. The softening agent may comprise, for example, a silicone. Silicone can be applied to the fabric by printing, coating or spraying. Even when silicones make tissue tissues feel soft, silicones can be relatively expensive and can decrease the durability of the sheet as measured by tensile strength and / or absorbed tensile energy.

In order to improve the durability, in the past, various resistance agents have been added to the tissue products. Resistance agents may be added to increase the dry strength of the tissue tissue or the wet strength of the tissue tissue. Some resistance agents are considered temporary, since they only maintain wet resistance in the tissue for a specific period of time. Temporary wet strength agents, for example, may aid resistance to bath tissues during use while not preventing bath tissues from disintegrating when they are pulled into a comfortable and discharged in water into a sewer line or a sewer line. septic tank.

Binding agents have also typically been applied to tissue products alone or in combination with creping operations. For example, a particular process that has proven to be very useful in producing paper towels and wipes is described in U.S. Patent No. 3,879,257 issued to Gentile et al., Which is incorporated herein by reference in its entirety. In the Gentile et al. Document, a process is described in which a bonding material is applied in a fine pattern defined on one side of a fibrous tissue. The tissue is then adhered to a creped surface heated 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 the Gentile et al. Document produces cleaning cloth products that have exceptional volume, extraordinary softness and good absorbency. The surface regions of the fabric also provide excellent strength, abrasion resistance, and dry cleaning properties.

Even though the process and the products described in the Gentile document and others, have provided many advances in the art of making paper cleaning products, other improvements in various aspects of the paper cleaning products that remain desired. For example, particular resistance agents are still needed that can be incorporated into the tissue tissues without significantly adversely impacting the softness of the tissues. A need also exists for a strength agent that can be incorporated into the fabric at any point during its production. For example, a need exists for a strength agent that can be added to a pulp sheet prior to the formation of the slurry, an aqueous suspension of fibers used to form a tissue of tissue, a tissue of tissue formed prior to drying, and / or a tissue of tissue that has been dried.

In addition, in the past, addictive compositions applied topically to tissue tissues have a tendency, under some circumstances, to create problems with blocking, which refer to the tendency of two adjacent tissue sheets to join together. As such, a need also exists for an additive composition or strength agent that is topically applied to a tissue of tissue without creating blocking problems.

SYNTHESIS OF THE INVENTION In general, the present disclosure is directed to wet and dry tissue products having improved properties due to the presence of an additive composition. The tissue product may comprise, for example, a bath tissue, a facial tissue, a paper towel, an industrial cleaning cloth, and the like. The tissue product may contain a stratum or may contain multiple strata. The additive composition can be incorporated into the tissue product in order to improve the strength of the product without significantly affecting the softness and / or blocking behavior of the product in a negative way. The additive composition can also increase strength without problems associated with blocking. The additive composition may comprise, for example, an aqueous dispersion containing a thermoplastic resin. The additive composition can be added to the tissue product via fiber from previous treatments prior to the generation of the slurry, the addition of wet end, and / or topically applying the tissue during or after the formation of the process. In one embodiment, the additive composition is applied topically to the tissue tissue during a creping operation.

In one embodiment, for example, the present disclosure is directed to a tissue product comprising a tissue of tissue containing pulp fibers. The tissue of tissue, for example, can have a dry volume of at least 3 cubic centimeters per gram. In accordance with the present disclosure, the tissue product further comprises an additive composition present in or on the tissue of tissue. The additive composition comprises non-fibrous olefin polymers, such as alpha-olefin polymers.

The additive composition, for example, may comprise a film-forming composition and the olefin polymer may comprise an interpolymer of ethylene and at least one comonomer comprising an alkene such as 1-octane. The additive composition may also contain a dispersing agent, such as a carboxylic acid. Examples of particular dispersing agents, for example, include fatty acids, such as oleic acid or stearic acid.

In a particular embodiment, the additive composition may contain an ethylene-octane copolymer in combination with an ethylene-acrylic acid copolymer. The ethylene-acrylic acid copolymer is not only a thermoplastic resin, but it can also serve as a dispersing agent. The ethylene-octane copolymer may be present in combination with the ethylene-acrylic acid copolymer in a weight ratio of from about 1:10 to about 10: 1, such as from about 2: 3 to about 3: 2. .

The olefin polymer composition may exhibit a crystallinity of less than about 50%, such as less than about 20%. The olefin polymer can also have a melt index of less than about 1000 grams per 10 minutes, such as less than about 700 grams per 10 minutes. The olefin may also have a relatively smaller particle size, such as from about 0.1 microns to about 5 microns when combined in an aqueous dispersion.

The additive composition can be combined with pulp fibers before forming the tissue tissue. Alternatively or in addition to, the additive composition may be topically applied to at least one side of the tissue tissue. For example, the additive composition can be used or printed on the tissue of tissue. In a particular embodiment, the tissue tissue is creped after the application of the additive composition.

The basis weight of the tissue may vary depending on the particular product being formed. For bath tissues and facial tissues, for example, tissue tissue can have a basis weight from about 6 grams per square meter to about 40 grams per square meter. For paper towels or cleansing cloth implements, on the other hand, the tissue of tissue can have a basis weight from about 15 grams per square meter to about 90 grams per square meter. The tissue tissue volume can also vary from about 3 cubic centimeters per gram to 20 cubic centimeters per gram, such as from about 5 cubic centimeters per gram to 15 cubic centimeters per gram.

In a particular embodiment, the additive composition may contain an ethylene-acrylic acid copolymer.

The ethylene-acrylic acid copolymer may be present in the additive composition in combination with a dispersing agent, such as a fatty acid.

The present disclosure is also directed to various processes for producing tissue products. In one embodiment, the process includes the steps of forming an aqueous suspension of fibers. The fibers comprise pulp fibers. The aqueous suspension of fibers is then formed in a tissue of tissue and the tissue of tissue is dried. In accordance with the present disclosure, the additive composition is applied to the aqueous fiber suspension or to the tissue tissue formed. The additive composition may comprise an aqueous dispersion containing a non-fibrous alpha-olefin polymer, an ethylene-acrylic acid copolymer, or mixtures thereof. In addition, the aqueous dispersion may contain a dispersing agent.

The additive composition can be applied to the tissue of tissue in an amount from about 0.1% to about 50% by weight, such as from about 0.5% to about 10% by weight.

Other features and aspects of the present invention are described in greater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS A complete and authoritative description of the present invention, including the best mode thereof for one with ordinary skill in the art, is pointed out more particularly in the remainder of the specification, including reference to the accompanying figures wherein: Figure 1 is a schematic diagram of a tissue tissue forming machine, illustrating the formation of a stratified tissue tissue having multiple layers in accordance with the present disclosure; Figure 2 is a schematic diagram of an embodiment of a process for forming dried, non-creped tissue of tissues for use in the present disclosure; Figure 3 is a schematic diagram of an embodiment of a process for forming wet creped tissue tissues for use in the present disclosure; Figure 4 is a schematic diagram of an embodiment of a process for applying the additive compositions to each side of a tissue tissue and creping a side of the tissue in accordance with the present disclosure; Figure 5 is a plan view of an embodiment of a pattern that is used to apply the additive compositions to tissue tissues made in accordance with the present disclosure; Figure 6 is another embodiment of a pattern that is used to apply the additive compositions to tissue tissues in accordance with the present disclosure; Figure 7 is a plan view of another alternative embodiment of a pattern that is used to apply the additive compositions to tissue tissues in accordance with the present disclosure; Figure 8 is a schematic diagram of an alternative embodiment of a process for applying an additive composition to one side of tissue tissue and creping one side of the tissue in accordance with the present disclosure; Y Figures 9 to 26 are the results obtained in the Examples as described below.

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

DETAILED DESCRIPTION It is understood by one with ordinary skill in the art that the present disclosure is a description of incorporative specimens only, and is not intended as a limitation to the broad aspects of the present disclosure.

In general, the present disclosure is directed to the incorporation of an additive composition in a tissue of tissue in order to improve the strength of the tissue. The fabric strength can be increased without significantly adversely affecting the perceived softness properties of the fabric. The additive composition may comprise a polyolefin dispersion. For example, the polyolefin dispersion may contain polymer particles that are relatively small in size, such as less than about 5 microns, in an aqueous medium when applied or incorporated into the tissue tissue. Once dried, however, the polymer particles are generally indistinguishable. For example, in an embodiment, the additive composition may comprise a film-forming composition that forms a discontinuous film. In some embodiments, the polyolefin dispersion may also contain a dispersing agent.

As will be described in more detail below, the additive composition can be incorporated into a tissue of tissue using various techniques and during different stages of production of the tissue product. For example, in one embodiment, the additive composition can be combined with an aqueous suspension of fibers that is used to form the tissue of the tissue. In an alternative embodiment, the additive composition can be applied to a dry pulp sheet that is used to form an aqueous suspension of fibers. In yet another embodiment, the additive composition can be topically applied to the tissue tissue while the tissue tissue is wet or after the tissue tissue has been dried. For example, in one embodiment, the additive composition can be applied topically to the tissue of the tissue during the creping operation. In particular, the additive composition has been found to be well suited for adhering a tissue of tissue to a creping surface during a creping process.

The use of the additive composition containing a polyolefin dispersion has been found to provide various benefits and advantages depending on the particular embodiment. For example, the additive composition has been found to improve the tensile strength of the geometric medium and the tensile energy of the geometrical medium absorbed from the treated tissue tissues in comparison to the untreated tissues. Furthermore, the above strength properties can be improved without significantly counteracting the impact of the stiffness of the tissue tissues relative to the untreated tissues and in relation to the tissue tissues treated with a silicone composition, as has been commonly in the art. past. Therefore, tissue tissues made in accordance with the present disclosure may have perceived softness that is similar to or equivalent to tissue tissues treated with a silicone composition. The tissue tissues according to the present disclosure, however, may have significantly improved strength properties at the same perceived levels of softness.

The increase in strength properties is also comparable to the prior art of tissue fabrics treated with bonding material, such as an ethylene-vinyl acetate copolymer. Problems with sheet blocking, however, which is the tendency of adjacent sheets to stick together, is significantly reduced when tissue tissues are made in accordance with the present disclosure as compared to those treated with an additive copolymer composition. ethylene-vinyl acetate, as has been done in the past.

The above benefits and advantages can be obtained by incorporating the additive composition in the tissue of tissue at virtually any point during tissue manufacture. The additive composition generally contains an aqueous dispersion comprising at least one thermoplastic resin, water, and optionally, at least one dispersing agent. The thermoplastic resin is present within the dispersion at a relatively small particle size. For example, the average volumetric particle size of the polymer can be less than about 5 microns. The current particle size may depend on several factors including the thermoplastic polymer that is present in the dispersion. Thus, the average volumetric particle size can be from about 0.05 microns to about 5 microns, such as less than about 4 microns, such as less than about 3 microns, such as less than about 2 microns. microns, such as less than about 1 miera. Particle sizes can be measured on a Coulter LS230 particle size analyzer or other suitable device. When present in the aqueous dispersion and when present in tissue tissue, the thermoplastic resin is typically found in non-fibrous form.

The particle size distribution of the polymer particles in the dispersion can be less than or equal to about 2.0, such as less than 1.9; 1.7; or 1.5.

Examples of aqueous dispersions that can be incorporated into the additive composition of the present disclosure are described, for example, in the United States of America patent application publication serial number 2005/0100754, the United States patent application publication. of America number 2005/0192365; PCT publication number WO 2005/021638, and PCT publication number WO 2005/021622, which are incorporated herein by reference.

The thermoplastic resin contained within the additive composition may vary depending on the particular application and the desired result. In one embodiment, for example, the thermoplastic resin is an olefin polymer. As used herein, an olefin polymer refers to a class of unsaturated open chain hydrocarbons, having the general formula of CnH2n. The olefin polymer may be present as a copolymer, such as an interpolymer. As used herein, a "substantially olefin polymer" refers to a polymer that contains less than about 1% substitution.

In a particular embodiment, for example, the olefin polymer may comprise an alpha-olefin interpolymer of ethylene with at least one comonomer selected from the group consisting of linear, branched or cyclic diene C4-C2o, or an ethylene vinyl compound, such as vinyl acetate, and a compound represented by the formula H2C = CHR, where R is a linear, branched or C-C20 branched alkyl group or a C6-C2o aryl group-Examples of comonomers include propylene, 1-butene, 3 -methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexane, 1-octane, 1-decene, and 1-dodecene. In some embodiments, the ethylene interpolymer has a density of less than about 0.92 grams per cubic centimeter.

In other embodiments, the thermoplastic resin comprises an alpha-olefin propylene interpolymer with at least one comonomer selected from the group consisting of linear, branched or cyclic diene C4-C20, or an ethylene vinyl compound, such as vinyl acetate, and a compound represented by the formula H2C = CHR, where R is a linear, branched C? -C2o or cyclic alkyl group or a C2-C2o aryl group. Examples of comonomers include propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexane, 1-octane, 1-decene , and 1-dodecene. In some embodiments, the comonomer is present at about 5% by weight to about 25% by weight of the interpolymer. In one embodiment, a propylene-ethylene interpolymer is used.

Other examples of thermoplastic resins that may be used in the present disclosure include homopolymers and copolymers (including elastomers) of an olefin such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1 pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-octene, 1-decene, and 1-dodecene, as typically represented by polyethylene, polypropylene, poly-1-butene, poly-3 methyl-l-butene, poly-3-methyl-l-pentene, poly-4-methyl-l-pentene, ethylene-propylene copolymer, ethylene-1-butene copolymer, and propylene-1-butene copolymer; copolymers (including elastomers) of alpha-olefin with a conjugated or non-conjugated diene as typically represented by ethylene-butadiene copolymer and ethylene-ethylidene copolymer norbomeno; and polyolefins (including elastomers) such as copolymers of two or more alpha-olefins with a conjugated or non-conjugated diene as typically represented by the ethylene-propylene-butadiene copolymer, ethylene-propylene-dichlopentadiene copolymer, ethylene-propylene-1 copolymer, 5-hexadiene, and ethylene-propylene-ethylene copolymer norbomeno; copolymers of ethylene-vinyl compound, such as ethylene-vinyl acetate copolymers with functional N-methylol comonomers; ethylene vinyl alcohol copolymers with functional N-methylol comonomers; ethylene-vinyl chloride copolymers; ethylene acrylic acid or ethylene (meth) acrylic acid copolymers, and ethylene- (meth) acrylate copolymer; styrenic copolymers (including elastomers) such as polystyrene, ABS, acrylonitrile-styrene copolymer; methylstyrene-ethylene copolymer; and styrene block copolymers (including elastomers) such as styrene-butadiene copolymer and hydrate thereof; and a triblock copolymer styrene-isoprene-styrene; polyvinyl compounds, such as polyvinyl chloride; polyvinylidene chloride; vinyl chloride-vinylidene copolymer chloride, polymethyl acetate, and polymethyl methacrylate; polyamides such as nylon 6, nylon 6-6, and nylon 12; thermoplastic polyesters such as polyethylene terephthalate and polybutylene terephthalate; polycarbonate, polyphenylene oxide, and the like. These resins can be used either alone or in combination with two or more.

In particular embodiments, polyolefins such as polypropylene, polystyrene, and copolymers thereof and mixtures thereof, as well as ethylene-propylene diene terpolymers are used. In some embodiments, the olefinic polymers include homogeneous polymers described in U.S. Patent No. 3,645,992 by Elston; high density polyethylene (HDPE) as described in United States of America patent number 4,076,698 issued to Anderson; heterogeneous branched linear low density polyethylene (LLDPE); branched heterogeneous ultra-low linear density (ULDPE); homogenous branched linear ethylene alpha / olefin copolymers; alpha olefin / ethylene substantially linear, homogeneously branched polymers which can be prepared for example, by a process described in U.S. Patent Nos. 5,272,236 and 5,278,272, the descriptions of said processes are incorporated herein by reference; and high pressure, polymerized radical free ethylene polymers and copolymers such as low density polyethylene (LDPE).

In yet another embodiment of the present invention, the thermoplastic resin comprises a carboxylic acid-ethylene copolymer, such as an acrylic acid-ethylene (EAA) and ethylene-methacrylic acid copolymers such as those available under the PRI brand names. ACOR ™, from the Dow Chemical Company; NUCREL ™ by DuPont; and ESCOR ™ of the ExxonMobil, and described in the patents of the United States of America numbers 4,599,592; 4,988,781; and 59,384,373, each of which is incorporated herein by reference in its entirety; and the ethylene-vinylacetate (EVA) copolymers. The polymer compositions described in U.S. Pat. Nos. 6,538,070; 6,566,446; 5,869,575; 6,448,341; 5,677,383; 6,316,549; 6,111,023; or 5,844,045, each of which is incorporated herein by reference in its entirety, are also suitable in some embodiments. Of course, polymer blends can also be used. In some embodiments, the mixtures include two different Ziegler-Natta polymers. In other embodiments, the mixtures may include mixtures of a Ziegler-Natta polymer and a metallocene. In still other embodiments, the thermoplastic resin used herein is a mixture of two different metallocene polymers.

In a particular embodiment, the thermoplastic resin comprises an alpha olefin interpolymer of ethylene with a comonomer comprising an alkene, such as 1-octane. Ethylene and octane copolymer may be present alone in the additive composition or in combination with another thermoplastic resin, such as acrylic acid-ethylene copolymer. Of particular advantage, the ethylene-acrylic acid copolymer is not only a thermoplastic resin, but also serves as a dispersing agent. For some embodiments, the additive composition must comprise a film-forming composition. It has been found that ethylene-acrylic acid copolymer can assist in forming films, while ethylene octane copolymer decreases stiffness. When applied to a tissue of tissue, the composition may or may not form a film within the product, depending on how the composition is applied and the amount of the composition is applied. When a film is formed on tissue tissue, the film can be continuous or discontinuous. When presented together, the weight ratio between ethylene and octane copolymer and ethylene-acrylic acid copolymer can be from about 1:10 to about 10: 1, such as from about 3: 2 about 2: 3.

The thermoplastic resin, such as ethylene and octane copolymer, may have a crystallinity of less than about 50%, such as less than about 25%. The polymer may have been produced using a single-site catalyst and may have an average molecular weight weight from about 15,000 to about 5 million, such as from about 20,000 to about 1 million. The weight distribution of the polymer molecule can be from about 1.01 to about 40, such as from about 1.5 to about 20, such as from about 1.8 to about 10.

Depending on the thermoplastic polymer, melt index of the polymer can be in the range from about 0.001 grams per 10 minutes to about 1,000 grams per 10 minutes, such as from about 0.5 grams per 10 minutes to about 800 grams per 10 minutes. For example, in one embodiment, the melt index of the thermoplastic resin can be from about 100 grams per 10 minutes to about 700 grams per 10 minutes.

The thermoplastic resin may also have a relatively low melting point. For example, the melting point of the thermoplastic resin may be less than about 140 degrees centigrade, such as less than about 130 degrees centigrade, such as less than 120 degrees centigrade. For example, in one embodiment, the melting point may be less than about 90 degrees centigrade. The glass transition temperature of the thermoplastic resin can also be relatively low. For example, the glass transition temperature may be less than about 50 degrees centigrade, such as less than about 40 degrees centigrade.

One or more thermoplastic resins may be contained within the additive composition in an amount from about 1% by weight to about 96% by weight. For example, the thermoplastic resin may be present in the aqueous dispersion in an amount of from about 10% by weight to about 70% by weight, such as from about 20% to about 50% by weight.

In addition to at least one thermoplastic resin, the aqueous dispersion may also contain a dispersing agent. A dispersing agent is an agent that aids in the formation and / or stabilization of the dispersion. One or more dispersing agents can be incorporated into the additive composition.

In general, any suitable dispersing agent can be used. In one embodiment, for example, the dispersing agent comprises at least one carboxylic acid, a salt of at least one carboxylic acid, or a carboxylic acid ester or carboxylic acid ester salt. Examples of carboxylic acids useful as dispersants include fatty acids such as montanic acid, stearic acid, oleic acid, and the like. In some embodiments, the carboxylic acid, the carboxylic acid salt, or at least one carboxylic acid fragment of the carboxylic acid ester or at least one carboxylic acid fragment of the carboxylic acid ester salt has less than 25 carbon atoms . In other embodiments, the carboxylic acid, the salt of the carboxylic acid, or at least one carboxylic acid fragment of the carboxylic acid ester or at least one carboxylic acid fragment of the carboxylic acid ester salt has 12 to 25 carbon atoms . In some embodiments, carboxylic acids, salts of carboxylic acids, at least one carboxylic acid fragment of the carboxylic acid ester or its salt has from 15 to 25 carbon atoms are preferable. In other embodiments, the number of carbon atoms is from 25 to 60. Some examples of salts comprise a cation selected from the group consisting of an alkali metal cation, alkaline earth metal cation, or ammonium alkyl cation or of ammonium.

In still other embodiments, the dispersing agent is selected from the group consisting of carboxylic acid-ethylene polymers, and salts thereof, such as copolymers of acrylic acid-ethylene, or copolymers of methacrylic acid-ethylene.

In other embodiments, the dispersing agent is selected from alkyl ether carboxylates, petroleum sulphonates, sulfonated polyoxyethylethane alcohol, sulfate or polyoxyethylated phosphated alcohols, polymeric ethylene oxide / propylene oxide / ethylene oxide dispersion agents, primary and secondary alcohol ethoxylates, glycosides alkyl and alkyl glycerides.

When the acrylic acid-ethylene copolymer is used as a dispersing agent, the copolymer can also serve as a thermoplastic resin.

In a particular embodiment, the aqueous dispersion contains an ethylene-octane copolymer, acrylic acid-ethylene copolymer, and a fatty acid, such as oleic acid or stearic acid. The dispersing agent, such as the carboxylic acid, may be present in the aqueous dispersion in an amount from about 0.1% to about 10% by weight.

In addition to the above components, the aqueous dispersion also contains water. The water can be added as de-ionized water, if desired. The pH of the aqueous dispersion is generally less than about 12, such as from about 5 to about 11.5, such as from about 7 to about 11. The aqueous dispersion may have a solids content of less than about of 75%, such as less than about 70%. For example, the solids content of the aqueous dispersion may be in the range of from about 5% to about 60%. In general, the solids content may be varied depending on the manner in which the additive composition is applied or incorporated into the tissue tissue. For example, when incorporated into the tissue of tissue during formation, such as being added with an aqueous suspension of fibers, a relatively high solids content can be used. When applied topically such as by spraying or printing, however, a lower solids content can be used in order to improve processing through the spraying or printing device.

While any method can be used to produce the aqueous dispersion, in an embodiment, the dispersion can be formed through a molten kneading process. For example, the kneader may comprise a Banbury mixer, a single thread extruder or a multi thread extruder. The melt kneading can be conducted under conditions that are typically used for the melt kneading of one or more thermoplastic resins.

In a particular embodiment, the process includes a melting of the components that make the dispersion. The molten kneading machine can include multiple inputs for the various components. For example, the extruder may include four entries placed in series. Also, if desired, a vacuum fan can be added in an optional extruder position.

In some embodiments, the dispersion is first diluted to contain about 1 to about 3 percent by weight and then, subsequently, further diluted to comprise more than 25% by weight of water.

When treating tissue tissues according to the present disclosure, the additive composition contains an aqueous polymer dispersion that can be applied to the tissue tissue topically or can be incorporated into the tissue tissue by being previously mixed with the fibers that are used to form the tissue. to the tissue. When applied topically, the additive composition can be applied to tissue tissue when it is dry or wet. In one embodiment, the additive composition can be applied topically to the tissue during a creping process. For example, in one embodiment, the additive composition can be sprayed onto the fabric or drum of the heated dryer in order to adhere the fabric to the dryer drum. The fabric can be creped from the dryer drum. When the additive composition is applied to the fabric and then adhered to the drum of the dryer, the composition can be uniformly applied over the surface area of the fabric or can be applied in accordance with a particular pattern.

When applied topically to a tissue of tissue, the additive composition can be sprayed into the tissue, extruded into the tissue, or printed on the tissue. When extruded into the fabric, any suitable extrusion device can be used, such as a coating slot extruder or a meltblown extruder. When printing on the fabric, any suitable printing device can be used. For example, an ink jet printer or a roto-etch printing device can be used.

In one embodiment, the additive composition may be heated prior to or during application to the tissue of tissue. The heating of the composition can decrease the viscosity to facilitate the application. For example, the additive composition can be heated to a temperature from about 50 degrees centigrade to about 150 degrees centigrade.

The tissue products made in accordance with the present disclosure may include single-layer tissue products or multi-layer tissue products. For example, in one embodiment, the product may include two strata or three strata.

In general, any suitable tissue of tissue can be treated in accordance with the present disclosure. For example, in one embodiment, the base sheet can be a tissue product, such as a bath tissue, a facial tissue, a paper towel, an industrial cleaning cloth, and the like. The tissue products typically have a volume density of at least 3 cubic centimeters per gram. The tissue products may contain one or more layers and may be made of any suitable type of fiber.

Fibers suitable for making tissue fabrics comprise any natural or synthetic cellulose fibers including, but not limited to, non-woody fibers, such as cotton, abaca, hemp, sabai grass, flax, esparto, straw, jute, bagasse, milkweed fibers , and pineapple fiber fibers; and to pulp or woody fibers, such as those contained in deciduous or coniferous trees, including softwood fibers, such as softwood fibers from the north and south; Hardwood fibers, such as eucalyptus, maple, fir, or poplar. Pulp fibers can be prepared in high production or low production form and can be pulped by any method, including kraft, sulfite, high production pulp production methods, and other known pulping methods. Fibers prepared from organosolv pulping methods can also be used, including the fibers and methods described in U.S. Patent No. 4,793,898 issued December 27, 1988 to Laamanen et al .; U.S. Patent No. 4,594,130 issued June 10 to Cheng et al .; and U.S. Patent No. 3,585,104. Useful fibers are also produced by anthraquinone pulp, exemplified by U.S. Patent No. 5,595,628, issued January 21, 1997 to Gordon et al.

A part of the fibers, such as up to 50% or less by dry weight, or from about 3% to about 30% by dry weight, can be synthetic fibers such as rayon, polyolefin fibers, polyester fibers, fibers of bicomponent sheath-core, multi-component binder fibers, and the like. One exemplary polyethylene fiber is Pulpex®, available from Hercules, Inc. (of Wilmington, Delaware). Any known bleaching method can be used. Types of synthetic cellulose fibers include rayon in all its varieties and other fibers derived from chemically-modified or viscose cellulose.

Chemically treated natural cellulose fibers can be used such as mercerized pulps, chemically crosslinked or crosslinked fibers, or sulfonated fibers. For good mechanical properties in using fibers for making paper, it may be desirable for the fibers to be relatively undamaged and largely unrefined or only slightly refined. While recycled fibers can be used, virgin fibers are generally useful for their mechanical properties and lack of contaminants. Mercerized fibers, regenerated cellulose fibers, cellulose produced by microbes, rayon, and other cellulose materials or cellulose derivatives can be used. Suitable papermaking fibers may also include recycled fibers, virgin fibers, or mixtures thereof. In certain embodiments capable of high volume properties and good compression, the fibers may have a Canadian Standard Freedom of at least 200, more specifically of at least 300, more specifically still of at least 400, and more specifically of at least 500 Other papermaking fibers that may be used in the present disclosure include cut paper or recycled fibers and high production fibers. High production fibers are those high production papermaking fibers produced by papermaking processes that provide a production of about 65% or more, more specifically about 75% or more, and even more specifically about 75%. % to around 95%. Production is the amount resulting from processing fibers expressed as a percentage of the initial wood mass. Such pulping processes include bleached chemo-thermomechanical pulp (BCTMP), chemo-thermomechanical pulp (CTMP), thermomechanical pressure / pressure pulp (PTMP), thermomechanical pulp (TMP), chemical thermomechanical pulp (TMCP), sulfite pulps, high production, high production kraft pulp, all of which leave the resulting fibers with high levels of lignin. High production fibers are well known for their stiffness in both dry and wet states relative to typical fibers made chemically pulped.

In general, any process capable of forming a paper web can also be used in the present description. For example, a papermaking process of the present invention may use creping, wet creping, double creping, etching, wet pressure, air pressure, continuous air drying, continuous air-creped drying, continuous drying. by air without creping, hydroentangled, placed by air, as well as other steps known in the art.

Also suitable products of the present disclosure are tissue sheets that are densified or patterned, such as tissue sheets described in any of the following United States of America patents numbers: 4,514,345 issued April 30, 1985 to Johnson and others; 4,528,239 granted on January 9, 1985 to Trokhan; 5,098,522, granted on March 24, 1992; 5,260,171 issued on November 9, 1993 to Smurkoski and others; 5,275,700 granted on January 4, 1994 to Trokhan; 5,328,565 issued on July 12, 1994 to Rasch et al .; 5,334,289 issued on August 2, 1994 to Trokhan et al .; 5,431,786 issued on July 11, 1995 to Rasch et al .; 5,496,624 granted on March 5, 1996 to Steltjes, Jr. , and others; 5,500,277 granted on March 19, 1996 to Trokhan and others; 5,514,523 issued on May 7, 1996 to Trokhan et al .; 5,554,467 issued September 10, 1996 to Trokhan et al .; 5,566,724 granted on October 22, 1996 to Trokhan et al .; 5,624,790 issued on April 29, 1997 to Trokhan and others; and 5,628,876 issued May 13, 1997 to Ayers et al., the descriptions of which are incorporated herein by reference to the extent they are not inconsistent with this. Such printed tissue sheets may have a network of densified regions that have been printed against a drum dryer by a printing fabric, and regions that are relatively less densified (e.g., "domes" on the tissue sheet) that they correspond to bypass ducts in the printing fabric, wherein the tissue sheet that is superimposed on the bypass ducts is deflected by an air pressure differential through the bypass duct to form a region of the low type of pillow. density or dome on the tissue sheet.

The tissue of tissue can also be formed without substantial amount of internal fiber-to-fiber bond strength. In this regard, the supplied fiber used to form the base fabric can be treated with a chemical deagglutinating agent. The de-agglutinating agent can be added to the fiber slurry during the pulping process or can be added directly to the main box. Suitable debinding agents are such as fatty dialkyl quaternary amine salts, mono fatty tertiary amine salts, primary amine salts, imidazoline quaternary salts, silicone quaternary salt, and unsaturated fatty acid alkyl amine salts. Other suitable de-binders 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 cationic silicone compositions as debinding agents.

In one embodiment, the deagglutinating agent used in the process of the present disclosure is an organic quaternary ammonium chloride and, particularly, a silicone-based amine salt of a quaternary ammonium chloride. For example, the debinding agent may be a PROSOFT® TQ 1003, marketed by Hercules Corporation. The debinding agent can be added to the fiber slurry in an amount from about 1 kilogram per metric ton to about 10 kilograms per metric ton of fibers present in the slurry.

In an alternative embodiment, the debinding agent can be an imidazoline-based agent. The imidazoline-based debinding agent can be obtained, for example, from Witco Corporation. The imidazoline-based debinding agent may be added in an amount of between 2.0 to about 15 kilograms per metric ton.

In one embodiment the de-binning agent can be added to the fiber supply in accordance with a process as described in the PCT application having the international publication number WO 99/34057, filed on December 17, 1998, or in the published PCT application in the international publication number WO 00/66835, filed on April 28, 2000, both of which are incorporated herein by reference. In the above publications, a process is described in which a chemical additive, such as a debinding agent, is adsorbed onto cellulose fibers to make paper at high levels. The process includes the steps of treating a fiber slurry for adsorption to occur, filtering the slurry to remove the unadsorbed chemical additives, and purifying the filtered pulp with fresh water before forming a non-woven fabric.

Optional chemical additives may also be added to the aqueous supply for making paper or embryo tissue to impart additional benefits of the invention. The following materials are included as examples of additional chemicals that can be applied to the fabric together with the additive composition of the present invention. Chemists are included as examples and are not intended to limit the scope of the invention. Such chemicals can be added at any point in the papermaking process, including being added simultaneously with the additive composition in the pulping process, wherein said additive or additives are directly mixed with the additive composition.

Additional types of chemicals that can be added to paper tissue include, but are not limited to, absorbency aids in the form of cationic, anionic, or non-ionic surfactants, humectants, and plasticizers such as low molecular weight polyethylene glycols and compounds. polyhydroxy such as glycerin and propylene glycol. Materials that provide skin health benefits such as mineral oil, aloe extract, vitamin E, silicone, lotions in general and the like can also be incorporated into the finished products.

In general, the products of the present invention can be used in conjunction with any known materials that are not antagonistic to their intended uses. Examples of such materials include, but are not limited to, odor control agents, such as odor absorbers, fibers and activated carbon particles, baby talc, baking soda, chelating agents, zeolites, perfumes, or other agents to mask the odor, cyclodextrin compounds, oxidants, and the like. Super absorbent particles, synthetic fibers, or films can also be used. Additional options include cationic dyes, optical brighteners, humectants, emollients, and the like.

Tissue fabrics that can be treated in accordance with the present disclosure can include a single homogeneous layer of fibers or can include a layered or layered construction. For example, tissue from a single stratum can include two or three layers of fibers. Each layer can have a different fiber composition. For example, with reference to Figure 1, an embodiment of a device for forming a multilayer stratified pulp supply is illustrated. As shown, a three layer main box 10 generally includes a top main box wall 12 and a wall of the lower main box 14. The main box 10 further includes a first divider 16 and a second divider 18, which separates the Three layers of fiber supply.

Each of the fiber layers comprises a dilute aqueous suspension of papermaking fibers. The particular fibers contained in each layer generally depend on the product being formed and the desired results. For example, the fiber composition of each layer may vary depending on whether a bath tissue product, facial tissue product, or the paper towel being produced. In one embodiment, for example, the middle layer 20 contains southern soft wood kraft fibers either alone or in combination with other fibers such as high production fibers. External layers 22 and 24, on the other hand, contain softwood fibers, such as softwood kraft from the north.

In an alternative embodiment, the middle layer may contain softwood fibers for strength, while the outer layers may comprise hardwood fibers, such as eucalyptus fibers, for perceived softness.

An endless displaced forming fabric 26, suitably supported and driven by rollers 28 and 30, receives the supply for making layered paper coming out of the main case 10. Once retained on the fabric 26, the fiber suspension in layers water passes through the fabric as shown by arrows 32. Water removal is achieved by combinations of gravity, centrifugal force and vacuum suction on the formation configuration.

The formation of multilayer paper webs is also described and shown in U.S. Patent No. 5,129,988 issued to Farrington, Jr. , which is incorporated here by reference.

In accordance with the present disclosure, the additive composition, in one embodiment, can be combined with the aqueous suspension of fibers that are supplied to the main box 10. The additive composition, for example, can be applied to only a single layer in the supply of Stratified fiber or all layers. When added during the wet end of the process or otherwise combined with the aqueous fiber suspension, the additive composition is reincorporated throughout the fibrous layer.

When combined at the wet end with the aqueous suspension of the fibers, a retention aid may also be present within the additive composition. For example, in a particular embodiment, the retention aid may comprise ammonium dimethyl poly-diallyl chloride. The additive composition can be incorporated into the tissue of the tissue in an amount from about 0.01% to about 30% by weight, such as from about 0.5% to about 20% by weight. For example, in one embodiment, the additive composition may be present in an amount of up to about 10% by weight. The percentages above are based on the solids that are added to the tissue tissue.

The basis weight of tissue tissues made in accordance with the present disclosure may vary with the final product. For example, the process can be used to produce bath tissues, facial tissues, paper towels, industrial cleansing cloths, and the like. In general, the basis weight of the tissue products can vary from about 10 grams per square meter to about 110 grams per square meter, such as from about 20 grams per square meter to about 90 grams per square meter. For bath tissue and facial tissues, for example, the basis weight may range from about 10 grams per square meter to about 40 grams per square meter. For paper towels, on the other hand, the basis weight can be in the range from about 25 grams per square meter to about 80 grams per square meter.

The tissue tissue volume can also vary from about 3 cubic centimeters per gram to 20 cubic centimeters per gram, such as from about 5 cubic centimeters per gram to 15 cubic centimeters per gram. The "volume" of the sheet is calculated as the quotient of the caliber of a dry tissue sheet, expressed in microns, divided by the dry basis weight, expressed in grams per square meter. The resulting leaf volume is expressed in cubic centimeters per gram. More specifically, the caliber is measured as the total thickness or a stack of ten representative sheets and dividing the total thickness of the stack of ten, where each sheet within the stack is placed with the same side up. The gauge is measured in accordance with the TAPPI test method number T411 om-89"Thickness (gauge) of Paper, Cardboard, and Combined Cardboard" with Note 3 for stacked sheets. The micrometer used to make it conform to the T411 om-89 which is an Emveco 200-A Tissue Caliber Tester, available from Emveco, Inc., of Newberg, Oregon. The micrometer has a load of 2.00 kilo-pascals (132 grams per square inch), an area of pressure per foot of 2500 square millimeters, a diameter per foot of pressure of 56.42 millimeters, a dwell time of 3 seconds and a rate of decrease of 0.8 millimeters per second.

In products of multiple strata, the basis weight of each tissue of tissue present in the product may also vary. In general, the total basis weight of a multiple layer product is generally the same as indicated above, such as from about 20 grams per square meter to about 110 grams per square meter. Therefore, the basis weight of each stratum can be from about 10 grams per square meter to about 60 grams per square meter, such as from about 20 grams per square meter to about 40 grams per square meter.

Once the aqueous suspension of fibers is formed in a tissue of tissue, the tissue of tissue can be processed using various techniques and methods. For example, with reference to Figure 2, a method for making dried tissue sheets in continuous form is shown. (For simplicity, the various tension rolls schematically used to define the various wraps of the fabric are shown, but not numbered It will be appreciated that variations of the apparatus and method illustrated in Figure 2 can be made without departing from the general process). A double-wire former is shown having a main paper box 34, such as a layered main box, which injects or deposits a jet 36 of an aqueous suspension of paper fibers into the forming fabric 38 placed on it. forming roll 39. The forming fabric serves to support and transport the newly formed wet tissue downward in the process as the fabric is partially dewatered to a consistency of about 10 percent by dry weight. Further dewatering of the wet fabric may be performed, such as by vacuum suction, while the wet fabric is supported by the forming fabric.

The wet fabric is then transferred from the forming fabric to a transfer fabric 40. In one embodiment, the transfer fabric can be delayed at a slower speed than the forming fabric in order to impart increased elongation in the fabric. This is commonly referred to as a "rushed" transfer. Preferably the transfer fabric can have a vacuum volume that is equal to or less than that of the forming fabric. The relative speed difference between the two fabrics can be from 0-60 percent, more specifically from around 15-45 percent. The transfer is preferably performed with the assistance of a vacuum shoe 42 such that the forming fabric and the transfer fabric simultaneously converge and separate at the leading edge of the vacuum slot.

The fabric is then transferred from the transfer fabric to the continuous drying fabric 44 with the aid of a vacuum transfer roller 46 or a vacuum transfer shoe, optionally again using a fixed aperture transfer as previously described. The continuous drying fabric may be moved at about the same speed or at a different speed relative to the transfer fabric. If desired, the continuous drying fabric may run at a slower speed for further improved elongation. The transfer can be done with vacuum assistance to ensure the deformation of the sheet to conform to the continuous drying fabric, thus producing the desired volume and appearance if desired. Suitable continuous drying fabrics are described in U.S. Patent No. 5,429,686 issued to Kal F. Chiu et al., And U.S. Patent No. 5,672,248 issued to Wendt et al., Which are incorporated by reference. .

In one embodiment, the continuous drying fabric contains high and long print knuckles. For example, the continuous drying fabric can have from about 5 to about 300 printing knuckles per square inch that are lifted at least about 0.005 inches above the plane of the fabric. During drying, the fabric can be microscopically arranged to conform to the surface of the drying fabric continuously and form a three-dimensional surface. Flat surfaces, however, can also be used in the present description.

The side of the fabric that contacts the drying fabric continuously is typically referred to as "the fabric side" of the paper fabric. The side of the fabric of the paper fabric, as described above, can have a shape that conforms to the surface of the drying fabric continuously after the fabric is dried in the continuous dryer. The opposite side of the paper fabric, on the other hand, is typically referred to as the "air side". The air side of the fabric is typically softer than the side of the fabric during the normal drying process continuously.

The level of vacuum used for tissue transfers can be from about 3 to about 15 inches of mercury (75 to about 380 millimeters of mercury), preferably about 5 inches (125 millimeters) of mercury. The vacuum shoe (negative pressure) can be increased or replaced by the use of positive pressure from the opposite side of the fabric to blow the fabric into the next fabric in addition to or in replacement to suck into the next fabric with vacuum. Also, a vacuum roller or rollers can be used to replace the vacuum shoe.

While supported by the continuous drying fabric, the fabric is finally dried to a consistency of about 94 percent or greater by the dryer continuously 48 t then transferred to a transport fabric 50. The dried base sheet 52 is transported to the reel 54 using the transport fabric 50 and the optional transport fabric 56. An optional pressurized dump roller 58 can be used to facilitate the transfer of the fabric from the transport fabric 50 to the fabric 56. Suitable transport fabrics for this The purpose is the Albano Internacional 84M to 94M and the Asten 959 or 937, all of which are relatively soft fabrics that have a fine pattern. Even when not shown, calendering reel or subsequent off-line calendering can be used to improve softness and smoothness of the base sheet.

In one embodiment, the spool 54 shown in FIG.

Figure 2 can run at a slower speed than the fabric 56 in a hasty transfer process to create crepe in the paper fabric 52. For example, the relative speed difference between the spool and the fabric can be from about 5 times. % to around 25% and, particularly from around 12% to around 14%. The hasty transfer on the reel can occur either alone or in conjunction with a transfer process upward as between the forming fabric and the transfer fabric.

In one embodiment, the paper fabric 52 is a textured fabric that has been dried in a three dimensional state such that the hydrogen bonds joining the fibers were substantially formed while the fabric was not in the flat, planar plane. For example, the fabric may be formed while the fabric is on a highly textured continuous drying fabric or other three dimensional substrate. Processes for producing fabrics continuously dried without creping are, for example, described in U.S. Patent Nos. 5,672,248 issued to Wendt et al .; 5,656,132 issued to Farrington and others; 6,120,642 granted to Lindsay and Burazin; 6,096,169 granted to Hermans and others; 6,197,154 granted to Chen and others; and 6,143,135 granted to Hada and others, all of which are hereby incorporated by reference in their entirety.

As described above, the additive composition can be combined with the aqueous suspension of the fibers used to form the tissue 52. Alternatively, the additive composition can be topically applied to the tissue tissue after it has been formed. For example, as shown in Figure 2, the additive composition can be applied to the tissue tissue before the dryer 48 or after the dryer 48.

In Figure 2, a process for producing tissue tissues dried continuously without creping is shown. It must be understood, however, that the additive composition can be applied to tissue tissues in other processes to make tissue. For example, with reference to Figure 3, an embodiment of a process for forming wet creping tissues is shown. In this embodiment, a main case 60 emits an aqueous suspension of fibers in a forming fabric 62 that is supported and driven by a plurality of guide rolls 64. A vacuum case 66 is disposed below the forming fabric 62 and is adapted to remove water from the fiber supply to assist in tissue formation. From the forming fabric 62, a formed fabric 68 is transferred to a second fabric 70, which may be either wire or a felt. The fabric 70 is supported by movement about a continuous path by a plurality of guide rollers 72. A pick-up roller 74 designed to facilitate the transfer of the fabric 68 from the fabric 62 to the fabric 70 is also included.

From the fabric 70, the fabric 68 in this embodiment is transferred to the surface of a heated drying drum 76 capable of rotating, such as a Yankee dryer.

In accordance with the present disclosure, the additive composition can be incorporated into the tissue of tissue 68 when combined with an aqueous suspension of fibers contained in the main box 60 and / or by topically applying the additive composition during the process. In a particular embodiment, the additive composition of the present disclosure can be applied topically to the tissue of tissue 68 while traveling on the guide rolls 72 or can be applied to the surface of the drying drum 76 for transfer to one side of the tissue of tissue 68. In this way, the additive composition is used to adhere the tissue tissue 68 to the drum dryer 76. In this embodiment, as the fabric 68 is transported through a part of the rotation path of the dryer surface, the Heat is imparted to the tissue causing most of the moisture contained within the tissue to be evaporated. The fabric 68 is then removed from the dryer drum 76 by a creping blade 78. The creped fabric 78 as formed further reduces the internal bond within the fabric and increases softness. Applying the additive composition to the fabric during creping, on the other hand, can increase the strength of the fabric.

In addition to applying the additive composition during tissue tissue formation, the additive composition can also be used in subsequent formation processes. For example, in one embodiment, the additive composition can be used during a crepe-printing process. Specifically, once it has been applied topically to a tissue tissue, the additive composition has been found to be suitable for adhering the tissue tissue to a creping surface, such as in a crepe-printing operation.

For example, once the tissue is formed and dried, in one embodiment, the additive composition can be applied to at least one side of the fabric and at least one side of the fabric can then be creped. In general, the additive composition can be applied to only one side of the fabric and only one side of the fabric can be creped, the additive composition can be applied to both sides of the fabric and only one side is creped, or the additive composition can be applied to each side of the tissue and each side of the tissue can be creped.

With reference to Figure 4, an embodiment of a system that can be used to apply the additive composition to the tissue of tissue and to crepe a side of the tissue is illustrated. The embodiment shown in Figure 4 can be online or offline from the process. As shown, the tissue 80 made in accordance with the process illustrated in Figure 2 or Figure 3 or in accordance with a similar process is passed through a first application station of the generally additive composition 82. The station 82 includes a pressure point formed by a soft rubber pressure roller 84 and a pattern rotogravure roller 86. The rotogravure roller 86 is in communication with a container 88 containing a first additive composition 90. The roller 80 rotogravure 86 applies the additive composition 90 to one side of the fabric 80 in a preselected pattern.

The fabric 80 is then contacted with a heated roller 92 after passing to a roller 94. The heated roller 92 can be heated to a temperature, for example, of up to about 200 degrees centigrade and particularly from about 100 degrees centigrade to about 100 degrees centigrade. 150 degrees Celsius. In general, the fabric can be heated to a temperature sufficient to dry the fabric and evaporate any water.

It should be understood that in addition to the heated roller 92, any suitable heating device can be used to dry the fabric. For example, in an alternative embodiment, the fabric can be placed in communication with an infrared heater in order to dry the fabric. In addition to using a heated roller or an infrared heater, other heating devices may include, for example, any suitable connection oven or a microwave oven.

From the heated roller 92, the fabric 80 can be advanced by pull rollers 96 to a second additive composition application station 98. The station 98 includes a transfer roller 100 in contact with a rotogravure roller 102, which is in communication with a container 104 containing a second additive composition 106. Similar to station 82, the second additive composition 106 is applied to the opposite side of the fabric 80 in a preselected pattern. Once the second additive composition is applied, the fabric 80 is adhered to a creping roller 108 by a pressure roller 110. The fabric 80 is transported on the surface of the creping drum 108 at a distance and then removed therefrom by the action of a creping blade 112. Creping blade 112 performs a controlled pattern creping operation on the second side of the tissue tissue.

Once creped, the tissue 80, in this embodiment, is pulled through a drying station 114. The drying station 114 can include any form of heating unit, such as in infrared heat-powered oven, energy microwave, hot air or similar. The drying station 114 may be necessary in some applications to dry the fabric and / or cure the additive composition. Depending on the selected additive composition, however, in other applications the drying station 114 may not be needed.

The amount that the tissue tissue is heated within the drying station 114 may depend on the particular thermoplastic resins used in the additive composition, the amount of the composition applied to the fabric, and the type of fabric used. In some applications, for example, the tissue tissue may be heated using a gas jet such as air at a temperature of about 100 degrees centigrade to about 200 degrees centigrade.

In the embodiment illustrated in Figure 4, even though the additive composition is being applied to each side of the tissue tissue, only one side of the tissue undergoes a creping process. It should be understood, however, that in other embodiments both sides of the fabric can be creped. For example, the heating roller 92 can be replaced with a creping drum such as 108 shown in Figure 4.

Creping the tissue as shown in Figure 4 increases the softness of the tissue by breaking the fiber-to-fiber bonds contained within the tissue tissue. Applying the additive composition outside the paper fabric, on the other hand, not only assists in the creping of the fabric but also adds dry strength, wet strength, elongation capacity, and tear resistance to the fabric. In addition, the additive composition reduces the release of lint from the tissue tissue.

In general, the first additive composition and the second additive composition applied to the tissue tissue as shown in Figure 4 may contain the same ingredients or may contain different ingredients. Alternatively, the additive compositions may contain the same ingredients in different amounts as desired.

The additive composition is applied to the base fabric as described above in a preselected pattern. In an embodiment, for example, the additive composition can be applied to the fabric in a lattice pattern, such that the pattern is between connected forming a network type design on the surface.

In a particular embodiment, however, the additive composition is applied to the fabric in a pattern representing a succession of discrete shapes. Applying the additive composition in discrete shapes, such as dots, provides sufficient resistance to the fabric without covering a substantial part of the surface area of the fabric.

In accordance with the present disclosure, the additive composition is applied to each side of the paper web as to cover from about 15% to about 75% of the surface area of the fabric. More particularly, the additive composition will cover from about 20% to about 60% of the surface area of each side of the fabric. The total amount of the additive composition applied to each side of the fabric can be in the range from about 1% to about 30% by weight, based on the total weight of the fabric., Such as from about 1% to about of 20% by weight, such as from about 2% to about 10% by weight.

In the above amounts, the additive composition can penetrate the tissue after it has been applied in an amount of up to about 30% of the total thickness of the tissue, depending on several factors. It has been discovered that, however, most of the additive composition mainly resides on the surface of the fabric after being applied to the fabric. For example, in some embodiments, the additive composition penetrates the fabric less than 5%, such as less than 3%, such that less than 1% of the thickness of the fabric.

With reference to Figure 5, an embodiment of a pattern can be used to apply an additive composition to a paper fabric in accordance with the present disclosure as shown. As illustrated, the pattern shown in Figure 5 represents a succession of discrete points 120. In one embodiment, for example, the dots can be spaced such that they are approximately from about 25 to about 35 dots per inch in the direction to the machine or in the direction transverse to the machine. The dots can have a diameter, for example, from about 0.01 inches to about 0.03 inches. In a particular embodiment, the dots may have a diameter of about 0.02 inches and may be present in the pattern such that approximately 28 dots per inch extend in the machine direction or in the cross machine direction. In this embodiment, the dots cover from about 20% to about 30% of the surface of one side of the paper fabric and, more particularly, they can cover about 25% of the surface area of the fabric.

In addition to the points, several other discrete shapes can also be used. For example, as shown in Figure 7, a pattern is illustrated in which the pattern is made up of discrete shapes that are each comprised of three elongated hexagons. In one embodiment, the hexagons may be about 0.02 inches long and may have a width of about 0.006 inches. Approximately 35 to 40 hexagons per inch can be spaced in the machine direction and cross machine direction. When hexagons are used as shown in Figure 7, the pattern can cover from about 40% to about 60% of the surface area of one side of the fabric, and more particularly can cover about 50% of the area of the fabric. tissue surface.

With reference to Figure 6, another embodiment of a pattern for applying an additive composition to a paper web is shown. In this embodiment, the pattern is a reticulated grid. More specifically, the cross-linked pattern is in the form of diamonds. When used, a cross-linked pattern can provide more tissue resistance compared to patterns that are made in a succession of discrete shapes.

The process that is used to apply the additive composition to the tissue tissue in accordance with the present disclosure may vary. For example, various printing methods can be used to print the additive composition in the base sheet depending on the particular application. Such printing methods can include direct engraving printing using two separate engravers for each side, gravure printing slid using duplex printing (both sides printed simultaneously) or station-to-station printing (consecutive printing of each side in one pass) . In another embodiment, a combination of slip and direct engraving printing can be used. In yet another embodiment, flexographic printing using either a duplex or sliding print from station to station can also be used when applying the additive composition.

In accordance with the process of the present disclosure, numerous different tissue products can be formed. For example, tissue products can be single-layer cleaning cloth products. The products can be, for example, facial tissues, bath tissues, paper towels, napkins, industrial cleaning cloths, and the like. As noted above, the basis weight can range anywhere from 10 grams per square meter to about 110 grams per square meter.

The tissue products made in accordance with the above processes may have relatively good volume characteristics. For example, tissue tissues can have a volume of more than about 8 cubic centimeters per gram, such as more than about 10 cubic centimeters per gram, such as about 11 cubic centimeters.

In one embodiment, tissue tissues made in accordance with the present disclosure can be incorporated into multiple layer products. For example, in one embodiment, a tissue of tissue made in accordance with the present disclosure can be attached to one or more other tissues of tissue to form a cleaning cloth product having desired characteristics. The other fabrics laminated to the tissue of the present invention can be, for example, a wet creped fabric, a calendered fabric, an etched fabric, a fabric continuously dried by air, a fabric continuously dried by creped air, a fabric continuously dried without creping, a fabric placed by air, and the like.

In one embodiment, when incorporating a tissue of tissue according to the present disclosure into a multi-stratified product, it may be desirable to only apply the additive composition to one side of the tissue and to after creping the treated side of the tissue. . The creped side of the fabric is then used to form an outer surface of a multiple layer product. The untreated and uncovered side of fabric on the other hand, is connected by any means to one or more layers.

For example, with reference to Figure 8, an embodiment of a process for applying the additive composition to only one side of a tissue tissue in accordance with the present disclosure is described. The process illustrated in FIG.

Figure 8 is similar to the process shown in Figure 4. In this regard, the reference numerals have been used to indicate similar elements.

As shown, a fabric 80 is advanced to a station for applying the additive composition generally as 98. The station 98 includes a transfer roller 100 in contact with a rotogravure roller 102, which is in communication with a container 104 containing an additive composition 106. In station 98, additive composition 106 is applied to one side of fabric 80 in the preselected pattern.

Once the additive composition is applied, the fabric 80 is adhered to a creping roller 108 by a pressure roller 110. The fabric 80 is made on the surface of the creping drum 108 for a distance and then removed by the action of a creping blade 112- Creping blade 112 performs a controlled pattern creping operation on the treated side of the fabric.

From the creping drum 108, the tissue 80 is supplied through a continuous drying station 114 which dries and / or cures the additive composition 106. The fabric 80 is then wound onto a roller 116 for use in forming products of multiple strata.

When only one side of the tissue 80 is treated with an additive composition, in one embodiment, it may be desirable to apply the additive composition in accordance with a pattern that covers more than about 40% of the surface area of one side of the tissue. . For example, the pattern can cover from about 40% to about 60% of the surface area of one side of the fabric. In a particular example, for example, the additive composition can be applied in accordance with the pattern shown in Figure 7.

In a specific embodiment of the present disclosure, a product of two layers is formed of a first tissue of paper and a second tissue of paper in which both tissues of paper are generally made in accordance with the process shown in Figure 8. For example, a first paper web made in accordance with the present disclosure can be attached to a second paper web made in accordance with the present disclosure in such a way that the creped sides of the webs form the outer surfaces of the resulting product. The creped surfaces are generally softer and smoother creating a product of two layers that have improved overall characteristics.

The manner in which the first tissue of paper is laminated to the second tissue of paper may vary depending on the particular application and the desired characteristics. In some applications, the alpha-olefin terpolymer of the present disclosure can serve as the de-agglutinating agent. In other applications, a binder material, such as an adhesive or a binder of fibers, is applied to one or both of the fabrics to join the fabrics together. The adhesive may be, for example, an adhesive latex, a starch-based adhesive, an acetate such as an ethylene vinyl acetate adhesive, a polyvinyl alcohol adhesive, and the like. It should be understood, however, that other binding materials, such as films and thermoplastic fibers can also be used to bind the fabrics. The binder material can be spread evenly over the surfaces of the fabric so as to securely join the tissues together or can be applied to selected locations.

The present description can be better understood with reference to the following examples.

EXAMPLE 1 To illustrate the properties of the tissue products made in accordance with the present disclosure, several tissue samples were treated with an additive composition and subjected to standardized tests. For comparison purposes, a sample of untreated tissue, a tissue sample treated with a silicone composition, and a tissue sample treated with an ethylene vinyl acetate binder were tested.

More particularly, the tissue samples comprise tissue sheets containing three piles. Each stratum of the tissue samples of three strata was formed in a process similar to that shown in Figure 3. Each stratum had a basis weight of about 13.5 grams per square meter. More specifically, each stratum was made from a stratified fiber supply containing a central layer of fibers placed between two outer layers of fibers. The outer layers of each stratum contained eucalyptus kraft pulp, obtained from Aracruz with offices in Miami, Florida, United States of America. Each of the two outer layers was approximately 33% of the total fiber weight of the sheet. The core layer, which was approximately 34% of the total fiber weight of the leaf, was composed of 100% northern softwood kraft pulp, obtained from Neenah Paper Inc., with offices in Alpharetta, Georgia, United States. United of America. The three strata were held together so that the tissue sides pressed on the dryer face the outer surfaces of the three-layer tissue sample.

The three-layer tissue sheets were coated with the adhesive compositions made according to the present disclosure. A second set of samples were coated with a silicone composition, while a third set of samples were coated with an ethylene vinyl acetate copolymer.

The tissue sheets were coated with the above composition using a rotogravure printer. The tissue sheet was supplied inside a rubber-rubber pressure point of the rotogravure printer to apply the above compositions to both sides of the tissue. The rotogravure rolls were electronically-recorded chromium-plated copper rolls supplied by Specialty Systems, Inc. of Louisville, Kentucky. The rollers had a line grid of 200 cells per linear inch and a volume of 8.0 billion cubic microns (BCM) per square inch of roll surface. The typical cell dimensions for this roller were 140 microns wide and 33 microns deep using a 130 degree engraving pen. The rubber backed offset applicator rolls were of a 75 Shore A hardened polyurethane supplied by the Amenmay Roller Company, of Union Grove, Wisconsin. The process was put to a condition having 0.375 inch interference between the gravure rollers and the rubber backing rollers and a 0.003 inch gap between the rubber backing rollers. The simultaneous offset / offset gravure printer was run at a speed of 150 feet per minute using a gravure roll speed adjustment (differential) to measure the above compositions to obtain the desired additional rate. The process gave an aggregate level of 6.0% by weight of the total aggregate based on the weight of the tissue (3.0% each side).

For samples treated with additive compositions made in accordance with the present disclosure, the following table provides the components of the additive composition for each sample. In the table given below, AFFINITY ™ EG8200 plastomer is an alpha olefin interpolymer comprising an ethylene-octene copolymer which was obtained from The Dow Chemical Company of Midland, Michigan, United States of America. The PRIMACOR ™ 59801 copolymer is a copolymer of acrylic acid-ethylene also obtained from The Dow Chemical Company. The acrylic acid-ethylene copolymer can serve not only as a thermoplastic polymer but also as a dispersing agent. The INDUSTRENE® 106 comprises oleic acid, which is marketed by Chemtura Corporation, of Middlebury, Connecticut. The polymer designated as "PBPE" is an experimental polypropylene-based elastomer or plastomer ("PBPE") having a density of 0.867 grams per cubic centimeter as measured by ASTM D792, a melt flow rate of 25 grams per 10 minutes, at 230 ° C and 2.16 kg as measured by ASTM D1238, and an ethylene content of 12% by weight of the "PBPE". These PBPE materials are taught in WO03 / 040442 and in U.S. Patent Application 60/709688 (filed August 19, 2005), each of which is incorporated herein by reference in its entirety. AFFINITY ™ PL1280 plastomer is an alpha-olefin interpolymer comprising an ethylene-octene copolymer which was also obtained from The Dow Chemical Company. The UNICID® 350 dispensing agent is a linear primary carboxylic acid functionalized surfactant with the hydrophobic comprising an average 26 carbon chain obtained from Baker-Petrolite Inc., of Sugar Land, Texas, United States of America. The dispensing agent AEROSOL® OT-100 is a dioctyl sodium sulfosuccinate obtained from Cytec Industries, Inc., of West Paterson, New Jersey, United States of America. The PRIMACOR ™ 59801 copolymer contains 20.5% by weight of acrylic acid and has a melt flow rate of 13.75 grams / 10 minutes at 125 ° C and 2.16 kg as measured by ASTM D1238. The AFFINITY ™ EG8200G plastomer has a density of 0.87 grams per cubic centimeter as measured by ASTM D792 and had a melt flow rate of 5 grams per 10 minutes at 190 ° C and 2.16 kilograms as measured by the ASTM standard. D1238 The AFFINITY ™ pll280G plastomer, on the other hand, has a density of 0.90 grams per cubic centimeter as measured by ASTM D792 and has a melt flow rate of 6 grams per 10 minutes at 190 ° C and 2.16 kilograms when measured by ASTM D1238.

The additive composition in each of the samples also contained the DOWICIL ™ 200 antimicrobial from The Dow Chemical Company, which is a condom with the active composition of 96% cis 1- (3-chloroallyl) -3,5,7- triaza-l-azoniadamantane chloride (also known as Quaternium-15).

Sample Polymer Dispersing Agent Agent No. (proportions by weight in parentheses) Concentrated dispersion (% by weight) 1 AFFINITY ™ EG8200 Unicid® 350 3.0 2 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (70/30) PRIMACOR ™ 59801 30.0 3 PBPE Unicid® 350 / AEROSOL® OT-100 3.0 / 2.5 4 PBPE / PRIMACOR ™ 59801 (70/30) PRIMACOR ™ 59801 30.0 AFFINITY ™ EG8200 / AFFINITY ™ PL1280 (80/20) Umcid® 350 / Industrene® 106 2.0 / 2.0 6 AFFINITY ™ EG8200 / AFFINITY ™ PL1280 (50/50) Umcid® 350 / Industrene® 106 2.0 / 2.0 7 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (75/25) PRIMACOR ™ 59801 / Industrene® 106 25.0 / 3.0 8 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (90/10) PRIMACOR ™ 5980 10.0 9 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (75/25) PRIMACOR ™ 59801 / Industrene® 106 25.0 / 3.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR ™ 59801 / Industrene® 106 40.0 / 6.0 11 AFFINITY ™ EG8200 / PRIMACOR "" 59801 (75/25) PRIMACOR ™ 59801 / Industrene® 106 25.0 / 3.0 12 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (90/10) PRIMACOR ™ 59801 / Industrene® 106 10.0 / 6.0 13 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (90/10) PRIMACOR ™ 59801 10.0 14 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR ™ 59801 / Industrene® 106 40.0 / 6.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (75/25) PRIMACOR ™ 59801 / Industrene® 106 25.0 / 3.0 16 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (90/10) PRIMACOR ™ 59801 10.0 17 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (75/25) PRIMACOR ™ 59801 / Industrene® 106 25.0 / 3.0 18 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (90/10) PRIMACOR1"59801 / Industrene® 106 10.0 / 6.0 19 AFFINITY ™ EG8200 / PRIMACORT "59801 (60/40) PRIMACOR ™ 59801 40.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR * "59801 40.0 21 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR ™ 59801 / Industrene® 106 40.0 / 6.0 Sample Size of Poly- Solids pH Viscosity Temp RPM Spindle No. particle dispersity (% by (cp) < ° C) polymer weight) (um) 1 1.08 1.83 54.7 10.0 83 22 50 RV2 2 1.48 2.40 41.0 10.5 338 20 50 RV3 3 0.72 1.42 55.5 10.2 626 21.1 50 RV3 4 0.85 2.06 42.8 10.2 322 21.5 50 RV3 0.86 1.68 55.2 9.7 490 55.0 50 RV3 6 1.08 1.85 52.4 10.9 296 21.7 50 RV3 7 1.86 4.46 50.1 9.4 538 21.1 50 RV3 8 5.55 2.67 49.3 9.0 < 75 21.6 100 RV3 9 1.18 2.48 46.1 10.5 270 21.2 50 RV3 1.60 1.58 41.1 8.7 368 21.7 50 RV3 11 1.69 3.68 48.8 9.7 306 22.1 50 RV3 12 1.34 2.24 51.0 10.2 266 21.4 50 RV3 13 1.16 2.25 46.6 10.5 85 21.5 100 RV3 14 1.01 1.57 32.1 10.3 572 21.7 50 RV3 1.53 3.50 50.1 9.9 396 22.3 50 RV3 16 9.86 4.14 51.2 8.7 < 75 21.5 50 RV3 17 1.57 3.26 49.8 9.9 436 22.4 50 RV3 18 0.89 1.51 51.1 12.3 342 21.5 50 RV3 19 0.71 2.12 40.0 11.3 448 22.1 50 RV3 1.63 2.23 42.0 8.6 178 22.0 100 RV3 21 1.49 1.87 39.0 10.3 210 20.2 50 RV3 For comparative reasons, the following samples were also prepared: Sample ID Composition Applied to the Sample Sample No. of the invention Not treated No. 1 Sample No. of the invention Product No. Y-14868 of Silicone number 2 emulsified obtained from G.E. Silicones Non-inventive sample AIRFLEX® binder 426 comprising number 3 an ethylene vinyl acetate copolymer emulsion obtained from Air Products, Inc. Non-Sample of the Invention ELVAX® 3175 binder comprising a number 4 ethylene vinyl acetate copolymer obtained from E. I. DuPont de Nemours of Wilmington, Delaware having a content of 28% vinyl acetate. The ethylene vinyl acetate copolymer was combined with UNICID 425, which is a functionalized carboxylic acid surfactant with a hydrophobe comprising an average 32 carbon chain obtained from Baker-Petrolite, Inc., of Sugarland, Texas.

The following tests were carried out on the samples Stress Resistance, Geometric Mean Stress Resistance (GMT), and Absorbed Geometric Absorption Medium Energy (GMTEA); The stress test was carried out using the tissue samples that were conditioned at 23 ° C +/- 1 ° C and 50% +/- 2% relative humidity for a minimum of 4 hours. Samples from the strata were cut into strips 3 inches wide in the machine direction (MD) and in the cross machine direction (CD) using a precision sample cutter model JDC 15M-10, available from Thwing -Albert Instruments, a business having offices located in Philadelphia, Pennsylvania, United States of America.

The measurement length of the tension frame was set to four inches. The tension frame was an Alliance RT / 1 frame run with a TestWorks 4 software. The tension frame and software are available from MTS Systems Corporation, a business having offices located in Minneapolis, Minnesota, United States of America.

A 3-inch strip was then placed in the jaws of the tension frame and subjected to an effort of 10 inches per minute to the point of sample failure. The tension on the tissue strip is monitored as a function of the effort. The calculated outputs included the peak load (grams-force / 3 inches, measured in grams-force), the peak stretch (%, calculated by dividing the elongation of the sample by the original length of the sample and multiplying by 100%), the% stretch @ 500 grams-force, the absorption of tensile energy (TEA) at break (grams-force * cm / cm2, calculated by integrating or taking the area under the stress-strain curve up to 70% of the sample failure) and inclination A (kilograms-force, measured as the inclination of the stress-strain curve from 57-150 grams-force).

Each tissue code (minimum of five duplicates) was tested in the machine direction (MD) and in the direction transverse to the machine (CD). The geometrical means of tensile strength and tension energy absorption (TEA) were calculated as the square root of the product of the machine direction (MD) and the cross machine direction (CD). This gave a performance of an average value that is independent of the direction of the test. The samples that were used are shown below.

Elastic Module (Maximum Inclination) and Geometric Medium Module (GMM) as Leaf Stiffness Measures: The elastic modulus (maximum inclination) E (kilogramf) is the elastic modulus determined in the dry state and is expressed in units of kilograms of force. Tappi conditioned samples with a width of 3 inches are placed in the tension tester jaws with a measurement length (extension between the jaws) of 4 inches. The jaws were separated at a crosshead speed of 25.4 centimeters per minute and the tilt is taken as at least the squares fit of the data between the tension values of 50 grams of force and 100 grams of force, or at least the adjustment of squares of the data between the values of tension of 100 grams of force and 200 grams of force, whichever is greater. If the sample is too weak to sustain an effort to at least 200 grams of force without failure, an additional layer is added repeatedly until the multi-strata sample withstood at least 200 grams of force without failure. The geometric mean modulus or the geometric mean inclination were calculated as the square root of the product of the elastic moduli in the machine direction (MD) and in the transverse direction (CD) (maximum inclinations), giving an average value that is independent of the direction of the test.

The results of the test are illustrated graphically in Figures 9 to 14. As shown by the results, the additive composition of the present description improved the geometric mean stress resistance of the samples and the total geometric average energy absorbed from the samples. without significantly impacting sheet stiffness compared to the untreated sample and the sample treated with the silicone composition. In addition, the ratio of the geometric mean modulus to the geometric mean stress for the samples treated with the additive compositions made according to the present disclosure showed similar characteristics in comparison to the sample treated with the ethylene vinyl acetate copolymer binder. It was noted, however, that the sheet blocking characteristics of the samples treated with the additive compositions were much better in relation to the sample treated with the ethylene vinyl acetate copolymer.

In addition to the results shown in the figures, the subjective softness test was also carried out on the samples. The perceived softness of the samples treated with the additive compositions of the present disclosure was equivalent to the perceived softness of the sample treated with the silicone composition.

EXAMPLE 2 In this example, the additive compositions were made according to the present disclosure were printed on a base fabric dried through non-creped air (UCTAD) according to a pattern and creped from a creping drum. The additive composition was used to adhere the base fabric to the drum. The samples were then tested and compared with a base fabric dried through non-creped air that was not subjected to a creping and printing process (sample number 1 not of the invention) and to a base fabric dried through non-creped air that it was subjected to a similar printing creping process using an ethylene vinyl acetate copolymer (sample number 2 not of the invention).

The base fabric dried through non-creped air was formed in a process similar to the process shown in Figure 2. The base sheet had a basis weight of about 50 grams per square meter. More specifically, the base sheet was made from a stratified fiber supply containing a central layer of fibers placed between two outer layers of fibers. Both outer layers of the base sheet contained 100% kraft pulp of soft northern wood. An outer layer containing about 10.0 kilograms (kg) / metric ton (Mton) of dry fiber deagglutinating agent (ProSoft® TQ1003 from Hercules, Inc.). The other outer layer contained about 5.0 kilograms (kg) / metric ton (Mton) of the dry fiber of a dry and wet strength agent (KYMENE® 6500, available from Hercules Incorporated, located in Wilmington, Delaware, United States). from America) . Each of the outer layers comprised about 30% of the total fiber weight of the sheet. The central layer, which comprised about 60% of the total fiber weight of the leaf, was composed of 100% by weight of kraft pulp of soft northern wood. The fibers in this layer were also treated with 3.75 kilograms / Mton of ProSoft® TQ1003 binder.

Several samples of the base sheet were then subjected to a printing creping process. The creping process of printing is generally illustrated in Figure 8. The sheet was supplied to a gravure printing line wherein the additive composition was printed on the surface of the sheet. One side of the sheet was printed using a direct rotogravure printing. The sheet was printed with a "dot" pattern of 0.020 in diameter, as shown in Figure 5 where 28 dots per inch were printed on the sheet in both directions of the machine and across the machine. The resulting surface area coverage was approximately 25%. The sheet was then pressed against a rotating drum making the sheet temperature varied from about 180 ° F to 390 ° F, such as from about 200 ° F to 250 ° F. Finally the sheet was rolled into a roll. Then, the resulting creped / printed sheet was converted into single layer paper towel rolls in a conventional manner. The finished product had an air-dried basis weight of approximately 55.8 grams per square meter.

As described above, for comparative purposes, a sample was subjected to a similar printing creping process using the AIRFLEX® 426 binder obtained from Air Products, Inc., of Allentown, Pennsylvania. AIRFLEX® 426 is a non-crosslinked polyethylene-vinyl acetate emulsion.

The additive compositions that were applied to the different samples are listed in the following tables. In the tables the AFFINITY ™ EG8200 plastomer comprises an interpolymer of an ethylene-octene copolymer, while PRIMACOR ™ 59801 comprises a copolymer of ethylene acrylic acid. The INDUSTRENE® 106 comprises an oleic acid. All three components were obtained from The Dow Chemical Company.

Sample Polymer Dispersion Agent Agent No. (proportions by weight in Dispersion brackets) Concentrate (% by weight) AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR ™ 59801 / Industrene® 106 40.0 / 6.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR 59801 ™ / Industrene® 106 40.0 / 6.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR 59801t '40.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 (60/40) PRIMACOR 59801 ™ 40.0 Sample Size of Poly- Solids pH Viscosity Temp RPM Spindle No. particle dispersity (% by (cp) ("O polymer (um) weight) 1 1.60 1.58 41.1 8.7 368 21.7 50 RV3 2 1.01 1.57 32.1 10.3 572 21.7 50 RV3 3 0.71 2.12 40.0 11.3 448 22.1 50 R 3 4 1.63 2.23 42.0 8.6 178 22.0 100 RV3 The antimicrobial DOWICIL ™ 200, antimicrobial, which is a condom with the active composition of 96% cis 1- (3-chloroallyl) -3,5,7-triaza-1-azoniadamantane chloride (also known as Quanternium-15) obtained from The Dow Chemical Company was also present in each of the additive compositions.

The samples were subjected to the tests described in example 1. In addition, the following test was also carried out on the samples.

Stress Test in Wet / Dry (% in the direction transverse to the machine) The dry tension test is described in Example 1, with the measurement length (jaw extension) being 2 inches. The wet tensile strength was measured in the same way as the dry strength except that the samples were wet before the test. Specifically, in order to wet the test, a 3 inch by 5 inch tray was filled with distilled or deionized water at a temperature of 23 ± 2 ° C. The water is added to the tray at about a depth of one centimeter.

A 3M general purpose scouring pad "Scotch-Brite" was cut to dimensions of 2.5 inches by 4 inches. A piece of masking tape approximately 5 inches long was placed along one of the 4-inch edges of the pad. The masking tape is used to retain the scrubbing pad.

The scrub pad is then placed in the water with the tape end facing up. The pad remained in the water at all times until the test was completed. The sample to be tested is placed on a blotting paper that conforms to the TAPPI T205 standard. The scrubbing pad is then removed from the water bath and taped lightly three times on the grid associated with the wet tray. The scrub pad is then placed gently on the sample parallel to the width of the sample in the approximate center. The scrubbing pad is then held in place for approximately one second. The sample is then immediately placed in the voltage tester and tested.

To calculate the ratio of wet / dry tensile strength, the wet tensile strength value was divided by the dry stress resistance value. The results obtained are illustrated in figures 15-19. As shown in the figures, the additive compositions improved the geometric mean tension and the total geometric average energy absorbed from the tissue samples without significantly impacting the leaf stiffness relative to the untreated sample. It was also observed during the test that the additive compositions did not create sheet blocking problems compared to the samples treated with the ethylene vinyl acetate copolymer.

EXAMPLE 3 In this example, the tissue tissues were generally made according to the process in Figure 3. In order to adhere the tissue to a creping surface which in this embodiment comprises a Yankee dryer, the additive compositions made according to the present description was sprayed onto the dryer before contacting the dryer with the fabric. The samples were then subjected to several standardized tests.

For comparison purposes, samples were also produced using a standard PVOH / KYMENE creping package.

In this example, the two-layer tissue products were produced and tested according to the same tests described in Examples 1 and 2. The following process was used to produce the samples.

Initially, 80 pounds of softwood kraft pulp (NSWK) was placed inside a pulp reducer and disintegrated for 15 minutes at a consistency of 4% at 120 ° F. Then the kraft pulp of air dried soft wood was refined for 15 minutes, transferred to a containment chest and subsequently diluted to approximately a 3% consistency. (Note: Refining fibrillates the fibers to increase their binding potential). Then, the kraft pulp of air dried soft wood was diluted to about 2% consistency and pumped into a machine chest, such that the machine chest contained 20 pounds of air drying of the soft wood kraft pulp air dried around a consistency of 0.2-0.3%. The above softwood fibers were used as the inner strength layer in a 3-layer tissue structure.

Two kilograms of KYMENE® 6500 available from Hercules, Incorporated, located in Wilmington, Delaware, United States of America, per metric ton of wood fiber and two kilograms of metric tonne of PAREZ® 631 NC wood fiber, available from LANXESS Corporation, located in Trenton, New Jersey, United States of America, were added and allowed to mix with the pulp fibers for at least 10 minutes before pumping the pulp solution through the head box.

Forty pounds of an air-dried kraft pulp of eucalyptus hardwood (EHWK) Aracruz, available from Aracruz, located in Rio de Janeiro, RJ, Brazil, was placed in a pulp reducer and disintegrated for 30 minutes at a consistency of 4% at 120 ° F. The kraft pulp of eucalyptus hardwood was then transferred to a deposit box and subsequently diluted to a consistency of about 2%.

Then, the kraft pulp solution of eucalyptus hardwood was diluted, divided into two equal quantities, and pumped to a consistency of about 1% in two separate machine chests, so that each machine chest contained 20 pounds of air dried kraft pulp of eucalyptus hardwood. The pulp solution was subsequently diluted to around a 0.1% consistency. The kraft pulp fibers of eucalyptus hardwood represent the two outer layers of the three-layer tissue structure.

Two kilograms of KIMENE® 6500 per metric ton of wood fiber were added and allowed to mix with the hardwood pulp fibers for at least 10 minutes before pumping the pulp solution through the headbox.

The pulp fibers from all three machine chests were pumped into the headbox at a consistency of about 0.1%. The pulp fibers of each machine chest were sent through separate manifolds in the head box to create a three-layer tissue structure. The fibers were deposited on a forming fabric. The water was subsequently removed with vacuum.

The wet sheet, at a consistency of about 10-20%, was transferred to a press felt or press cloth where it was further drained. The sheet was then transferred to a Yankee dryer through a pressure point through a pressure roller. The consistency of the wet sheet after the pressure roller pressure point (consistency of the back pressure roller or PPRC) was approximately 40%. The wet sheet was adhered to the Yankee dryer due to an adhesive that is applied to the surface of the dryer. The spray bars below the Yankee dryer sprayed either a package of adhesive, which is a mixture of polyvinyl alcohol / KYMENE® / Rezosol 2008M, or an additive composition according to the present description on the surface of the dryer. . The Rezosol 2008M is available from Hercules Incorporated, located in Wilmington, Delaware, United States of America.

A typical adhesive package load on the continuous hand sheet former (CHF) typically consisted of 25 gallons of water, 5000mL of a solution of 6% solids of polyvinyl alcohol, 75mL of a KYMENE® solution of 12.5% solids and 20mL of a Rezosol 2008M solution of 7.5% solids.

The additive compositions according to the present description varied in solids content from 2.5% to % The sheet was dried to about a 95% consistency when moving in the Yankee dryer and creping blade. The creping blade subsequently scraped off the tissue sheet and the small amounts of dryer coating from the Yankee dryer. The base sheet of creped tissue was then rolled over a 3 inch core in soft rolls for conversion. Two rolls of creped tissue were then rolled and stacked together so that both creped sides were on the outside of the two-layer structure.

The mechanical ripple on the edges of the structure kept the strata together. The stratum sheet was then cut over the edges to a standard width of about 8.5 inches and folded. The tissue samples were conditioned and tested.

The additive compositions of the present disclosure that were applied to the samples and tested in this example are as follows: Sample Polymer Scatter Agent% Agent No. (proportions by weight in Solid dispersion brackets) Concentrate (% by weight) AFFINITY ™ EG8200 / PRIMACOR ™ 59801 2.5 1 (60/40) PRIMACOR ™ 59801 / Industrene® 106 40.0 / 6.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 2.5 2 (60/40) PRIMACOR 59801 ™ 40.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 3 (60/40) PRIMACOR 59801 ™ / Industrene® 106 40.0 / 6.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 4 (60/40) PRIMACOR 59801 ™ 40.0 AFFINITY ™ EG8200 / PRIMACOR ™ 59801 10 (60/40) PRIMACOR 59801 ™ / Industrene® 106 40.0 / 6.0 Sample Size of Poly- Solids pH Viscosity Temp RPM Spindle No. particle dispersity (% by (cp) ("O polymer (um) weight) 1 1.01 1.57 32.1 10.3 572 21.7 50 RV3 2 0.71 2.12 40.0 11.3 448 22.1 50 RV3 3 1.01 1.57 32.1 10.3 572 21.7 50 RV3 4 0.71 2.12 40.0 11.3 448 22.1 50 RV3 1.01 1.57 32.1 10.3 572 21.7 50 RV3 The antimicrobial DOWICIL ™ 200, which is a preservative with the active composition of 96% of cis l- (3-chloroallyl) -3,5,7-triaza-1-azoniadamantane chloride (also known as Quaternium-15) obtained from The Dow Chemical Company was present in each of the additive compositions.

As shown above, the percentage of solids in the solution for the different additive compositions was varied. Varying the solids content in solution also varies the amount of solids incorporated in the base fabric. For example, at a 2.5% solids solution, it was estimated that from about 35 kilograms / MT to about 60 kilograms / MT of solids is incorporated into a tissue of tissue. At 5% solids solution, it was estimated that from about 70 kilograms / MT to about 130 kilograms / MT are incorporated into the tissue tissue. At 10% solids solution, it is estimated that from about 140 kilograms / MT to about 260 kilograms / MT of solids are incorporated into the tissue tissue.

The results of this example are illustrated in Figures 20-24. As shown in Figure 20 for example, the geometric mean stress strength of the sample made according to the present disclosure was greater than the non-inventive sample treated with the conventional bonding material. Similar results were also obtained for the total geometric average energy absorbed.

In addition to testing the properties of the samples, some of the samples were also photographed.

For example, referring to Figures 25A, 25B, 25C and 25D, four of the samples are shown at a magnification of 500 times. In particular, FIG. 25A depicts a photograph of the non-invention sample, FIG. 25B is a photograph of the sample number 1, FIG. 25C is a photograph of the sample number 3, and FIG. 25D is a photograph of the sample number.

. As shown, the additive composition of the present disclosure tends to form a non-continuous film on the tissue tissue surface. In addition, the larger the solution solids, the larger the amount of film formation. These figures indicate that the additive composition generally remains on the surface of the tissue tissue.

Referring to Figure 26, there is shown a photograph of a cross section of the same sample illustrated in Figure 25D. As can be seen in the photograph, even at 10% solids solution, the majority of the additive composition remains on the surface of the tissue tissue. In this aspect, the additive composition penetrates the fabric to an amount of less than about 25% of the thickness of the fabric, such as less than about 15% of the thickness of the fabric, such as less than about 5% of the thickness of the fabric. .

In this manner, it is believed that the additive composition provides a significant amount of resistance to the tissue of tissue. In addition, because the film is non-continuous, the transmission properties of the fabric are not adversely affected. Of particular advantage, these results are also obtained without a substantial increase in tissue tissue rigidity and without a substantial decrease in perceived softness.

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 the aspects of the various incorporations can be exchanged in whole or 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

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

1. A moist or dry tissue product comprising: a tissue of tissue comprising pulp fibers, the tissue of tissue having a dry volume of at least 3 cc / g; Y an additive composition present on or in the tissue of tissue, the additive composition comprises a non-fibrous olefin polymer, a carboxylic acid-ethylene copolymer or mixtures thereof.

2. A tissue product as claimed in clause 1, characterized in that the additive composition comprises a film-forming composition.

3. A tissue product as claimed in clauses 1 or 2, characterized in that the olefin polymer comprises an ethylene alpha-olefin interpolymer and at least one comonomer selected from the group consisting of a linear, branched or cyclic diene. C4 to C20 vinyl acetate, and a compound represented by the formula H2C = CHR, wherein R is a linear, branched or cyclic alkyl group Ci to C2O? Or an aryl group at C20, or the alpha-olefin polymer comprises a copolymer of propylene with at least one comonomer selected from the group consisting of ethylene, a linear, branched or cyclic diene C4 to C2o and a compound represented by formula H2C = CHR, wherein R is a linear, branched or cyclic alkyl group Ci to C2o, or an aryl group & to C2o.

. A tissue product as claimed in clauses 1, 2 or 3, characterized in that the additive composition further comprises a dispersing agent.

5. A tissue product as claimed in clause 4, characterized in that the dispersing agent comprises carboxylic acid, a carboxylic acid salt, a carboxylic acid ester or a carboxylic acid ester salt.

6. A tissue product as claimed in clause 4, characterized in that the dispersing agent comprises fatty acid.

7. A tissue product as claimed in clause 4, characterized in that the dispersing agent comprises a carboxylic acid-ethylene copolymer.

8. A tissue product as claimed in clauses 1, 2, 3, 4, 5, 6, or 7, characterized in that the olefin copolymer comprises an alpha-olefin interpolymer of ethylene and a comonomer comprising propylene, 1- butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-octene, 1-decene, or 1-dodecene.

9. A tissue product as claimed in clauses 1, 2, 4, 5, 6, or 7, characterized in that the olefin polymer comprises an interpolymer of ethylene and an alkene, and wherein the additive composition further comprises an acid carboxylic acid and a copolymer of acrylic acid-ethylene.

10. A tissue product as claimed in any one of the preceding clauses, characterized in that the additive composition is present on or in the tissue of the tissue in an amount of from about 0.1% to about 20% by weight.

11. A tissue product as claimed in clause 9, characterized in that the weight ratio between the olefin and the ethylene acrylic acid copolymer varies from about 1:10 to about 10: 1.

12. A tissue product as claimed in any one of the preceding clauses, characterized in that the additive composition was combined with the pulp strips before the formation of the tissue tissue.

13. A tissue product as claimed in any one of the preceding clauses, characterized in that the additive composition was applied topically to at least one side of the tissue tissue.

14. A tissue product as claimed in clause 13, characterized in that the additive composition was sprayed or printed on the tissue of tissue.

15. A tissue product as claimed in clause 13, characterized in that the tissue tissue has been creped after the application of the additive composition.

16. A tissue product as claimed in any one of the preceding clauses, characterized in that the olefin polymer has a crystallinity of less than about 50%..

17. A tissue product as claimed in any one of the preceding clauses, characterized in that the olefin has a melt index of less than 1,000 grams per 10 minutes at 190 ° C and 2.16 kilograms according to the ASTM D1238 test.

18. A tissue product as claimed in any one of the preceding clauses, characterized in that the olefin polymer has an average particle size of volume of from about 0.1 microns to about 5 microns before being incorporated into the tissue of tissue.

19. A tissue product as claimed in any one of the preceding clauses, characterized in that the tissue of tissue contains pulp fibers in an amount of at least about 50% by weight.

20. A process for producing a tissue product comprising: forming an aqueous suspension of fibers, the fibers comprise pulp fibers; forming the aqueous suspension of fibers in the tissue of the tissue; dry the tissue; Y apply to the dry fibers before forming the aqueous suspension of fibers, to the aqueous suspension of fibers or to the tissue of tissue formed an additive composition, the additive composition comprises a non-fibrous olefin polymer, a copolymer of acrylic acid-ethylene or mixtures of them and a dispersing agent.

21. A process as claimed in clause 20, characterized in that the additive composition is applied to the pulp sheet before the formation of an aqueous suspension of fibers.

22. A process as claimed in clause 20, characterized in that the additive composition is applied topically to the tissue of tissue.

23. A process as claimed in clause 20, characterized in that the additive composition is combined with the aqueous suspension of fibers prior to tissue tissue formation.

24. A process as claimed in clauses 20, 21, 22 or 23, characterized in that the additive composition comprises an olefin polymer and an ethylene acrylic acid polymer, the olefin polymer comprises an interpolymer of ethylene and an alkene, the dispersing agent comprises carboxylic acid.

25. A process as claimed in clauses 20, 21, 22, 23 or 24, characterized in that the additive composition is present on or in the tissue tissue formed in an amount of from about 0.1% to about 20% after that the tissue is dried.

26. A process as claimed in clauses 20, 21, 22, 23, 24 or 25, characterized in that the tissue of the tissue is creped after the additive composition is applied to the tissue.

27. A process as claimed in clauses 20 to 25 or 26, characterized in that the polymer contained in the additive composition has a particle size of less than about 5 microns.

28. A process as claimed in clause 26, characterized in that the additive composition is applied to the surface of a creping drum and the tissue tissue is then pressed against the drum where the additive composition has been applied, the Tissue tissue is then creped from the creping drum. SUMMARY Tissue products containing an additive composition are described. The additive composition, for example, comprises an aqueous dispersion containing an olefin polymer, a carboxylic acid-ethylene copolymer, or mixtures thereof. The olefin polymer may comprise an interpolymer of ethylene and octene, while the carboxylic acid-ethylene copolymer may comprise a copolymer of acrylic acid-ethylene. The additive composition may also contain a dispersing agent, such as a fatty acid. The additive composition can be incorporated into the tissue by being combined with the fibers that are used to form the tissue. Alternatively, the additive composition can be applied topically to the tissue after the tissue has been formed. For example, in one embodiment, the additive composition can be applied to the fabric as a creped adhesive during the creping operation. The additive composition can improve the strength of the tissue without substantially affecting the perceived softness of the tissue in an adverse manner.