MX2007007874A - Soft and durable tissue products containing a softening agent - Google Patents

Abstract

Fibrous products containing a durable softening agent are disclosed. The softening agent generally comprises a polysiloxane containing a plurality of first functional groups. In order to improve the wet retention of the softening agent on cellulosic fibers, the softening agent is reacted with a retention agent. The retention agent generally comprises a cationic polymer having a second functional group. In one embodiment, for instance, the softening agent contains epoxy groups or anhydride groups, while the retention agent contains amine groups. Products that may be made according to the present invention include tissue products, wipes and other absorbent articles.

Description

SOFT AND DURABLE TISU PRODUCTS CONTAINING A SOFTENING AGENT Background of the Invention Softness and flexibility are key attributes for tissue and absorbent articles. One method to improve the softness or flexibility in these products is to add a softening agent such as a silicone. Typically, the softening agent is added to the pulp fibers through a pretreatment or, for some tissues, applied topically to the exterior surface. When pre-treated silicone pulp is used in the tissues, the softness gained can be further improved by layering the fibers. Although the softness and flexibility gained by adding silicone additives are advantageous, this class of additives tend to have incomplete retention in the fibers, tends to be hydrophobic and can cause problems with absorbency. Due to the limitations of absorbency, there has been a lot of work in developing the chemistry and the application of wettable silicones. Although these alternative silicones have helped to mitigate absorbency problems, they have also aggravated retention efficiency. For example, a part of the moisturizing softening agent can remove the absorbance of pretreated fibers when in contact with water or body fluids.

For tissue machines, non-retained softening agents are re-circulated through a "short curl" water recycling and can contaminate other fibers, fabrics, and creped surfaces. This is especially problematic for layered tissue products where softening agents are desired in the outer layers and the strength agents are prized in the center of the product. For absorbent articles, non-retained silicon reduces surface tension and can interfere with runoff, and the capacity of the superabsorbent particle.

Therefore, there is currently a need for a method for improving the retention of softening agents in the pre-treated pulp. For example, there is currently a need for a method for improving retention in wettable silicones in cellulosic fibers used in the production of tissue products and other absorbent articles.

Synthesis of the Invention In general, the present disclosure is directed to durable and soft absorbent products, such as tissue products that have been treated with an agent softener. The softening agent in one embodiment may be a polysiloxane that has been modified to decrease the hydrophobicity of the compound. In accordance with the present invention, a retention agent is used in combination with a softening agent in order to improve the retention of the softening agent in the cellulosic fibers under aqueous conditions.

In the formation of an absorbent article, the cellulosic fibers are first pretreated with the softening agent. The fibers are then used alone or in combination with other fibers to form an article, such as a tissue of tissue. The retention agent is incorporated into the tissue. The retention agent reacts or is otherwise associated with the softening agent that causes the softening agent to crosslink, to form more durable and less possible bonds to remove the absorbency of the fibers.

In one embodiment, for example, the present invention is directed to the production of tissue products, such as facial tissue, paper towels, industrial cleaning cloths and the like. The tissue product includes at least one tissue of tissue containing cellulose fibers. At least a portion of the cellulosic fibers have been pretreated with the softening agent comprising a polysiloxane containing a plurality of a first functional group. The tissue of tissue, for example, can have a weight base from around 10 grams per square meter to around 100 grams per square meter.

A retention agent is also incorporated in the tissue of tissue. The retention agent comprises a polymer that contains a plurality of a second functional group. The second functional group, for example, may comprise an amine group, an amide group, an anhydride group, an epoxy group, an epihalohydrin group, or mixtures thereof. The retention agent is reacted with the polysiloxane. The retention agent is present in the tissue of tissue in an amount sufficient to increase the retention of the polysiloxane to the cellulosic fibers by at least 10% under aqueous conditions. For example, the retention of the polysiloxane can be increased by greater than about 50%, higher by about 100%, higher by about 200%, or even higher by about 300% under aqueous conditions. In some embodiments, the tissue product may also exhibit relatively high low release properties and moisture resistance. The tissue product may also have a wetting time of less than about 200 seconds.

In one embodiment, the polysiloxane softening agent can have the following formula: R7 R Ru | Si O- |s¡-o- Si-o | Si 0 | | SI-- Ra Re R 10, 1 t Where, X and Z are integral = 0. And it's an integral > 0, the mole ratio of X to (X + Y + Z) is from about 0.05% to about 95%, the "ratio of Y to (X + Y + Z) is from about 0% to about 25%, the halves of R ° - R9 are independent of any organofunctional group including Ci or higher alkyl groups, of ethers, polyethers, polyesters, amines, imines, amides, epoxy, anhydride, aldehyde, carboxylic, or epihalohydrin groups which include the alkyl and alkenyl analogs of such groups, the R 10 moiety is an amino functional moiety, R 11 is a polyether functional group having the generic formula: -R 12- ( R13-0) a- (R140) b-R15, where R12, R13, and R14 independently are linear or branched Ci_4 alkyl groups, and R15 is H or an alkyl group Ci -.30; and, "a" and "b" are whole from about 1 to about 100.

As previously shown, the first functional group contained in the polysiloxane softening agent may comprise epoxy groups, amine groups, aldehyde groups, carboxylic groups, epihalohydrin groups, and mixtures thereof. Vinyl grafts of polysiloxanes can also be used. The first functional group may be contained in the polysiloxane in an amount of from about 0.1 mol% to about 75 mol%. The polysiloxane can have a viscosity of from about 5 centipoise to about 5,000 centipoise and can be incorporated into the tissue of tissue in an amount of from about 0.1 kg / T to about 100 kg / T, such as from about 1 kg / T up to around 20 kg / T.

In a particular embodiment, the first functional groups contained in the polysiloxane comprise epoxy groups, anhydride groups or mixtures thereof, and wherein the plurality of the second functional groups contained in the retention agent may comprise amine groups. In an alternate embodiment, the first functional group contained on the polysiloxane may comprise amine groups, while the second functional group contained on the retention agent also comprises amine groups. In this embodiment, better reaction conditions can occur if the softening agent and the retention agent contact one another under acidic conditions, for example, the pH of the surrounding solution can also be less than about 7, such as less than around 5, such as from around 3 to around In order for the softening agent to react with the retention agent, a catalyst, an energy supply, or both are necessary. In an incorporation, for example, in order to react the retention agent with the softening agent, the tissue tissue can be heated using infrared rays, microwaves, ultrasound, plasma, steam, or any other suitable thermal supply. The reaction between the retention agent and the softening agent can occur before the tissue tissue dries to final drying or during tissue drying. Examples of retention agents that can be used in the present invention include the glyoxylated polyacrylamine resins, the polyamide-polyamine-epichlorohydrin resins, the polyethyleneimine resins, the polyvinylamine resins, the copolymers thereof, and the mixtures thereof. the same. The retention agent can be incorporated into the tissue product in an amount of from about 0.1 kg / T to about 20 kg / T, such as from about 0.1 kg / T to about 10 kg / T and, in one embodiment, from around 1 kg / T to around 5 kg / T.

The tissue product can be made in accordance with any process for making appropriate paper. For example, the tissue of tissue may be creped or may comprise a dry fabric of continuous air without creping. In one embodiment, tissue tissue can be made from a fiber supply of stratified containing separate layers of fibers. For example, the tissue of tissue may contain three layers of fibers. The cellulosic fibers pretreated with a softening agent may be contained only within at least one outer layer of the fabric. The resulting tissue product may have a single fold or may be a multiple-pleated product.

In an alternate embodiment of the present invention, the pretreated cellulosic fibers may be contained in an absorbent article, such as a diaper, an incontinence product, a napkin for women, and the like. In a particular embodiment, for example, an absorbent layer can be formed in an air laying process. The absorbent layer may contain cellulosic fibers pretreated with a polysiloxane softening agent as described above. According to the present invention, a retention agent can be incorporated in the absorbent layer and reactivated with the softening agent in order to improve retention of the softening agent in the cellulosic fibers. The retention agent, for example, can be incorporated into an aqueous solution and sprayed onto the absorbent layer. Alternatively, the cellulosic fibers pretreated with the retention agent can be incorporated into the absorbent layer and then reactivated with the softening agent. In order for the reaction to occur, for example, the absorbent layer may be slightly dampened and then subjected to a sufficient supply of energy to cause the reaction.

When air-laid fabrics are formed, the cellulosic fibers may comprise lint which is pretreated with the softening agent or retention agent. The superabsorbent particles can also be incorporated into the absorbent tissue. Once the softening agent is reactivated with the retention agent, the absorbent layer can be incorporated into any suitable absorbent article. Other features and aspects of the present invention are described in more detail below.

Detailed description It should be understood by one of ordinary skill in the art that the present disclosure is a description only of example embodiments, and is not intended to limit the broad aspects of the present invention.

In general, the present disclosure is directed to a method for improving retention of softening agents in cellulosic fibers, such as pulp fibers. The softening agent may comprise, for example, a polysiloxane, such as a chemically modified polysiloxane which may have decreased hydrophobicity. In accordance with the present invention, the cellulosic fibers can first be pretreated with a softening agent. During the formation of an article containing the pretreated cellulosic fibers, the softening agent is reactivated with a retention agent. The retention agent, for example, may comprise a cationic polymer having functional groups that react with functional groups in the softening agent. Once reactivated with the retention agent, the retention of the softening agent in the cellulosic fibers can be increased to at least 10% under aqueous conditions. For example, the retention of the softening agent can be increased to at least 50%, at least 60%, at least 70%, at least 80%, at least 100%, at least 200%, or can still increase to at least 300%.

In one embodiment of the present invention, the softening agent and the retention agent are incorporated into a tissue product, such as a facial tissue, a bath tissue, a paper towel, an industrial cleaning cloth, a bandage, a medical cover, or the like. In an alternate embodiment, the softening agent and the retention agent are incorporated into other types of absorbent articles, such as a diaper, an incontinence product of adults, a product for women's hygiene, and the like. When they are incorporated into an absorbent article as described above, the agent Softener and retention agent may be present in an absorbent structure containing, for example, superabsorbent particles. When a diaper is constructed, for example, the diaper may include a cover layer and a liner. The absorbent structure can be placed between the cover layer and the liner.

The softening agent that can be used according to the present invention may comprise a polysiloxane. The polysiloxane, for example, can be modified to include a first functional group. The functional group, for example, may comprise epoxy groups, anhydride groups, amine groups, aldehyde groups, carboxylic groups, epihalohydrin groups, and mixtures thereof. Vinyl grafts of polysiloxanes can also be used. As previously described, the cellulose fibers are pretreated with the above softening agents. A retention agent is then reactivated with the softening agent to improve the wet retention of the softening agent in the cellulose fibers. The retention agent may, for example, comprise a cationic polymer containing a second functional group. The second functional group, for example, may comprise amine groups, amide groups, anhydride group, aldehyde groups, epoxy groups, epihalohydrin groups, and mixtures thereof.

In a particular embodiment of the present invention, the first functional groups in the polysiloxane comprise epoxy groups or anhydride groups, while the second functional groups contained in the retention agent comprise amine groups. In another embodiment of the present invention, both the first functional group in the softening agent and the second functional group in the retention agent comprise amine groups.

As will be described in more detail, the cellulose fibers pretreated with the softening agent can be contacted with the retention agent in various ways in the formation of absorbent articles including the tissue products. Once the cellulose fibers pretreated with the softening agent are contacted with the retention agent, the softening agent and the retention agent, in many embodiments, need to be subjected to an energy supply in order to cause a reaction to occur between the two polymers. The energy supply, for example, may comprise thermal energy. Although it is unknown, it is believed that a chemical link is formed between the first functional groups in the softening agent and in the second functional groups in the retention agent. For example, although it is unknown, a covalent bond can be formed between the softening agent in the cellulose fibers and the retention agent. Other junctions, however, can form that include other physiochemical linkages, hydrogen bonds and the like between the softening agent and the retention agent. Lately, it is believed that some type of network is formed that prevents the softening agent from being released from the cellulosic fibers even in the presence of water.

As previously described, the softening agent generally comprises a polysiloxane having several functional groups. The particular polysiloxane used in the present invention may vary depending on the particular application and the desired result. Acceptable polysiloxanes are characterized in that they have a backbone structure as follows: wherein R 'and R "may be a broad range of organ and non-organ groups including mixtures of such groups and wherein n is an integral > 2. These polysiloxanes can be linear, branched or cyclic. These include a wide variety of polysiloxane copolymers containing various compositions of the functional groups, therefore, R 'and R "may actually represent many different types of groups within the same polymer molecule. The organ or non-organ groups may be able to react with cellulose to covalently, ionically or binding hydrogen to the polysiloxane to the cellulose and also to react with the retention agent of the present invention. These functional groups may also be able to react with themselves to form matrices intertwined with cellulose. The scope of the invention should not be construed as limiting by a particular polysiloxane structure so long as that polysiloxane structure provides an attribute of softness.

A specific class of polysiloxanes suitable for the invention has the general formula: Wherein the moieties R1-R3 independently can be any organofunctional group including Ci or higher alkyl groups, ethers, polyethers, polyesters, amines, imines, amides, epoxy, anhydride, aldehyde, carboxylics, epihalohydrin, or other functional groups including alkyl and alkenyl analogues of such groups and Y is an integrated > 1.

The functionalized polysiloxanes and their aqueous demolitions are well-known commercially available materials. Polysiloxanes having the following structure are very suitable for the purposes of the present invention and are well known in the art and readily available: Where, X and Y are integral = 0, Y is an integral > 0. The mole ratio of X to (X + Y + Z) can be from about 0.05% to about 95%. The ratio of Y to (X + Y + Z) can be from about 0% to about 25%. The halves of R ° -R9 may be independent of any organofunctional group including Ci or higher alkyl groups, ether, polyether, polyester, amine, imine, amide, epoxy, anhydride, aldehyde, of carboxylics, epihalohydrin or other functional groups including the alkyl and alkenyl analogs of such groups. The R 10 moiety is an amine functional moiety that includes but is not limited to the primary amine, the amine secondary, tertiary amines, quaternary amines, unsubstituted amides and mixtures thereof. An exemplary RIO moiety contains one amine group per constituent or two or more amine groups per substituent, separated by a branched or linear alkyl chain of Ci or higher. R11 is a polyether functional group having the generic formula: -R12- (R13-0) a- (R140) b-R15, wherein R12, R13, and R14 independently are linear or branched C1-4 alkyl groups; R15 can be H or a C1-30 alkyl group; and, "a" and "b" are integral from about 1 to about 100, more specifically from about 5 to about 30. The example aminofunctional polysiloxanes are the Wetsoft CTW family manufactured and sold by Wacker, Inc. Exemplary epoxy polysiloxanes are the Sipell family (RE 35 F and RE 63 F) and the anhydride polysiloxanes are the IM 86 family, both manufactured and sold by Wacker, Inc. Other exemplary polysiloxanes can be found in the US Pat. United States America No. 6,432,270 granted to Liu and others.

In accordance with the present invention, cellulose fibers such as pulp fibers are pretreated with the softening agents described above. Softening agents that are particularly well suited for pretreating fibers according to the present invention have epoxy functional groups, anhydride functional groups, and / or amine functional groups. In one embodiment, the softening agent is absorbed into the cellulose fibers without reactivate the softening agent with any of the fibers. The partial surface coverage of the polysiloxane in the fiber is typically the objective. An efficient way to pretreat cellulose fibers is by draining the polysiloxane during or after the dry coated production of the fibers. The treated fibers can be aged at room temperature for at least a week to ensure optimal distribution of the polysiloxane in the fibers and maximum retention through the Vander Waals and dipole forces. The cellulose fibers pretreated with the polysiloxane are further reduced to pulp in a fibrous suspension and possibly mixed with some other untreated fibers to form an article of the present invention.

As used herein, pretreated fibers refers to fibers that have been pretreated with, for example, a softening agent before any process step that is used to form an absorbent layer, such as a layer of tissue. As previously described, for example, the pretreated fibers are treated with a softening agent and then dried before being used in the production of any fibrous articles. The fibers are then pretreated in accordance with the present invention can comprise any appropriate cellulose fibers, including any fiber to make appropriate paper. The fibers before being pre-treated do not need to be chemically modified in any way before contact with the softening agent.

The cellulose fibers pretreated with the softening agent according to the present invention should have a sufficient concentration of reactive sites to ensure sufficient and efficient reaction with the retention agent in order to improve wet retention and yield superior softness characteristics. For example, the softening agent may contain the first functional groups in an amount of from about 0.1 mol% to about 75 mol%, such as from about 1 mol% to about 50 mol%. The mole percentage of the functional groups in the softening agent may depend on the particular softening agent used in the process. For example, the mole percentage may vary from about 0.1 mol% to about 5 mol% or from about 10 mol% to about 20 mol%.

When the softening agent comprises a polysiloxane, polysiloxane can be selected as having sufficient molecular weight and to ensure a retention in the cellulose fibers and the softness of the tissue while being sufficiently low to ensure easy processability. For example, the molecular weight of the polysiloxanes used in the present invention may have a viscosity in the range of around 5 centipoise to around 5,000 centipoise.

The amount of softening agent incorporated in the cellulose fibers can also vary depending on the desired result. In general, the polysiloxane can be contacted with the cellulose fibers in an amount of about 0.1 kg / T to about 100 kg / T, such as from about 1 kg / T to about 20 kg / T. For example, in a particular embodiment, a polysiloxane containing functional groups can be used which contacts the cellulose fibers in amounts of about 3 kg / T to about 10 kg / T.

As previously described, the retention agents that can be used in the present invention generally include cationic polymers that contain a functional group. The functional group may comprise amine groups, amide groups, anhydride groups, aldehyde groups, epoxy groups, epihalohydrin groups, and mixtures thereof.

Retention agents that are particularly worldwide bred for use in the present invention include glyoxylated polyacrylamide resins, polyamide-polyamine-epichlorohydrin resins, resins of polyethyleneimine, polyvinylamine resins, copolymers thereof, and mixtures thereof.

Exemplary commercially available compounds include the PAREZ ™ 631 NC and PAREZ® 725 resins which are cationic glyoxalated polyacrylamides available from Cytec Industries (West Paterson, New Jersey). These and similar resins are described in U.S. Patent No. 3,556,932 to Coscia et al., And in U.S. Patent No. 3,556,933 to Williams et al. HERCOBOND 1366, manufactured by Hercules, Inc. (Wilmington, Delaware) is another cationic glyoxalated polyacrylamide that can be used in accordance with the present invention. Polyamide-polyamine-epichlorohydrin type resins such as KYMENE 557H are sold by Hercules, Inc. (Wilmington, Delaware). Such materials have been described in the patents granted to Keim (patent of the United States of America No. 3,700,623 and in the patent of the United States of America No. 3,772,076), granted to Petrovich (patent of the United States of America No 3,885,156, U.S. Patent No. 3,899,388, U.S. Patent No. 4,129,528 and U.S. Patent No. 4,147,586) and the one issued to van Eenam (U.S. Pat. United of America No. 4,222,921). Copolymers of poly (vinylamine-polyvinylformamide) [PVAm] are sold by BASF under the brand name CATIOFAST. Other cationic resins include polyethylene imine resins and aminoplast resins obtained by the reaction of formaldehyde with melamine or urea.

The amount of retention agent added to the cellulose fibers according to the present invention can vary depending on the retention agent by selecting, the softening agent present in the fibers, the amount of softening agent present in the fibers, and various other factors . In general, for example, the retention agent can be added to the fibers in an amount of about 0.1 kg / T to about 20 kg / T, such as from about 0.1 kg / T to about 10 kg / T. . In a particular embodiment, for example, the retention agent can be added to the fibers in an amount from about 1 kg / T to about 5 kg / T.

The manner in which the retention agent is contacted with the softening agent in the presence of the cellulose fibers may vary depending on the type of product that is formed. In one embodiment, for example, the retention agent and the softening agent may be added to the dried coated pulp during the pulping process either in the wet final supply or in the formed sheet before being dried. In another embodiment, cellulosic fibers pretreated with a softening agent can be combined with cellulose fibers portrayed with the retention agent to produce a fibrous product according to the present invention. Once the article is formed or during the formation of the article, the mixture of cellulose fibers can be contacted with water to an aqueous solution and then subjected to a sufficient energy supply for the retention agent to react with the softening agent. When air-laid fabrics are formed, for example, the fibrous layer containing the mixture of pretreated cellulose fibers can be sprayed with water and then heated in order to cause the reaction to occur between the softening agent and the retention agent. .

When the tissue tissues are formed according to a wet laying process, the tissue tissue can at least partially be made of cellulose fibers pretreated with the softening agent. The retention agent can then be incorporated into the tissue tissue at any time before drying the tissue. For example, in one embodiment, the retention agent can be added to an aqueous suspension of fibers containing cellulose fibers pretreated with the softening agent. The aqueous suspension can then be deposited on a forming surface in the formation of a tissue of tissue.

In an alternate incorporation, the retention agent can be topically applied to a tissue of wet containing cellulose fibers pretreated with a softening agent. The retention agent, for example, can be sprayed on the wet fabric or printed on the wet fabric using any suitable printing technique. Examples of suitable printing techniques include rotogravure printing, flexographic printing, and ink jet printing, and the like. As previously described, an energy supply is typically necessary in order to react the softening agent with the retention agent. When wet tissue tissues are formed, the energy supply necessary for the reaction can be supplied from the dryer in the process which can be, for example, a continuous air dryer or a hot drum. In alternate embodiments, however, the process can be configured for the reaction to occur before the tissue tissue is dried. For example, in prior to the dryer, the process may include an energy device to supply sufficient amounts of energy for the reaction to occur. The energy can be supplied in the form of thermal energy, infrared energy, microwaves, ultrasound, plasma, vapor, and the like.

When air-laid fabrics are formed in accordance with the present invention, the retention agent can also be topically applied to a fabric laid with air containing cellulosic fibers pretreated with the softening agent. The retention agent, for example, can be supplied in the form of a solution and sprayed or printed on the fabric. After being applied to the air-laid fabric, an energy supply as described above can be used to initiate the chemical reaction between the softening agent and the retention agent.

In some applications, better results may be obtained if the softening agent is contacted with the reaction agent under acidic conditions. For example, the pH of the environment when the softening agent contacts the retention agent can be less than about 7, such as less than about 5. For example, in one embodiment, the pH of the environment can be from around from 3 to about 5. In order to reduce the pH of the environment during contact between the softening agent and the retention agent, for example, the retention agent can be applied to the fabric or to an aqueous suspension of fibers in a solution. acidic. Alternatively, an acidic solution can be applied to the fibrous tissue after the softening agent and the retention agent have been added to the tissue. Reducing the pH as previously described has been found to be especially effective when the functional groups in the softening agent and the functional groups in the holding agent are both amine groups.

Several different types of products and articles can be made according to the present invention containing cellulose fibers treated with the reaction product of the softening agent and the retention agent. For example, in one embodiment, the present invention is directed to the formation of tissue products, such as a facial tissue, a tissue for the bath and paper towels. The tissue products may have a basis weight, for example, from about 6 grams per square meter to about 100 grams per square meter or greater. For example, in one embodiment, the tissue product may have a basis weight of from about 10 grams per square meter to about 100 grams per square meter. Facial tissue, for example, typically has a basis weight of from about 10 grams per square meter to about 40 grams per square meter. Paper towels, on the other hand, typically have a basis weight of from about 35 grams per square meter to about 80 grams per square meter.

The tissue products that incorporate the chemical additives of the present invention can be made from any suitable processes. The tissue products incorporated with a chemical additive according to the present invention can be made by any appropriate processes. For the tissue sheets of the present invention, both creping and creping methods can be used. The production of uncreped tissue is described in United States of America Patent No. 5,772,845 issued on June 30, 1998 to Farrington, Jr. and others, the description of which is hereby incorporated by reference to the extent that is not contradictory herein. The production of creped tissue is described in US Pat. No. 5,637,194 issued June 10, 1997 to Ampulski et al .; in U.S. Patent No. 4, 529, 480 issued July 16, 1985 to Trokhan; in the patent of the United States of America No. 6,103,063 granted on August 15, 2000 to Oriaran and others; and in U.S. Patent No. 4,440,597 issued April 3, 1984 to Wells and others, the descriptions of all of which are incorporated herein by reference to the extent that they are not contradictory herein. Also suitable for the application of the aforementioned chemical additives are the densified or printed patterned tissue sheets, such as the tissues of writings in any of the following patents of the United States of America: No. 4,514,345 issued on the 30th. April 1985 to Johnson and others; No. 4, 528, 239 granted on July 9, 1985 to Trokhan; No. 5,098,522 issued March 24, 1992; No. 5, 260, 171 issued on November 9, 1993 to Smurkoski and others; No. 5,275, 700 granted on January 4, 1994 to Trokhan; No. 5,328,565 issued on July 12, 1994 to Rasch et al .; No. 5,334,289 issued on August 2, 1994 to Trokhan et al .; No. 5,431,786 issued on July 11, 1995 to Rasch et al .; No. 5, 496, 624 granted on March 5, 1996 to Steljes, Jr. and others; No. 500,277 grants Trokhan et al. of March 19, 1996; No. 5,514,523 issued May 7, 1996 to Trokhan et al .; No. 554,467 granted on September 10, 1996 to Trokhan and others; No. 5,566,724 issued on October 22, 1996 to Trokhan et al .; No. 5,624, 790 granted on April 29, 1997 to Trokhan et al .; and No. 5, 628, 876 issued May 13, 1997 to Ayers et al., the descriptions of all of which are incorporated herein by reference to the extent to which they are not contradictory herein. 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 (eg, "domes" on the tissue sheet) that they correspond to deflection conduits in the printing fabric, wherein the tissue sheet superimposed on the deflection conduits is deflected by an air pressure differential through the deflection conduit to form a dome or region similar to a low pillow. density on the tissue sheet.

Various drying operations may be useful in the manufacture of the tissue products of the present invention. Examples of such drying methods include, but are not limited to, drum drying, continuous drying, steam drying such as superheated steam drying, displacement dehydration, Yankee drying, infrared drying, drying. with microwave, the drying with radiofrequency in general, and pulsed drying, as described in U.S. Patent No. 5,353,521, granted October 11, 1994 to Orloff and in U.S. Patent No. 5,598,642 granted on February 4, 1997 to Orloff and others, the descriptions of both of which are here incorporated by reference to the extent of which are not contradictory here. Other drying technologies may be used, such as methods employing differential gas pressure that include the use of air presses as described in U.S. Patent No. 6,096,169 issued August 1, 2000 to Hermans. and others and in the United States of America patent No. 6,143, 135 granted on November 7, 2000 to Hada and others, the descriptions of both of which are incorporated herein by reference to the extent that they are not contradictory. here. Also relevant are the paper machines written in United States of America Patent No. 5,230,776 issued on July 27, 1993 to I.A. Anderson and others.

The tissue product may contain a variety of fiber types, in addition to the modified cellulose, both natural and synthetic. In an embodiment, the tissue product comprises softwood and hardwood fibers. The total proportion of hardwood pulp fibers to the softwood pulp fibers within the tissue product, which include individual tissue sheets that make the product can widely vary. The ratio of hardwood pulp fibers to softwood pulp fibers can be in the range of about 9: 1 to about 1: 9, more specifically from about 9: 1 to about 1: 4, and more specifically from about 9: 1 to about 1: 1. In an embodiment of the present invention, the hardwood pulp fibers and the softwood pulp fibers can be mixed before the formation of the tissue sheet thereby producing a homogeneous distribution of hardwood pulp fibers and of soft wood pulp fibers in the Z direction of the tissue sheet. In another embodiment of the present invention, the fibers of hardwood pulp and softwood pulp fibers can be layered to thereby give a heterogeneous distribution of hardwood pulp fibers and softwood pulp fibers in the Z direction of the tissue sheet. In another embodiment, the hardwood pulp fibers may be located in at least one of the outer layers of the tissue product and / or the tissue sheets wherein at least one of the inner layers may comprise fibers of the pulp of the tissue. soft wood In yet another embodiment the tissue product contains recycled or secondary fibers which optionally contain synthetic or virgin fibers.

Additionally, synthetic fibers can also be used in the present invention. The discussion here with respect to pulp fibers is understood to include synthetic fibers. Some appropriate polymers that can be used to form the synthetic fibers include, but are not limited to: polyolefins, such as polyethylene, polypropylene, polybutylene, and the like; polyesters, such as polyethylene terephthalate, glycolic polyacid (PGA), polylactic acid (PLA), poly (P-malic acid) (PMLA), poly (e-caprolactone) (PCL), poly ( p-dioxanone) (PDS), the poly (3-hydroxybutyrate) (PHB), and the like; and, polyamides, such as nylon and the like. The natural or synthetic cellulosic polymers, including but not limited to: cellulosic ester; the cellulose ethers; cellulose nitrates; cellulose acetates; cellulose acetate butyrates; ethyl cellulose; regenerated celluloses, such as viscose, rayon, lyocell and the like; cotton, linen, hemp; and mixtures thereof can be used in the present invention. The synthetic fibers can be located in one or all of the layers and sheets comprising the tissue product.

When the tissue tissue contains a layered configuration, the synthetic fibers may be located in either the layer containing the treated fibers, the layer containing the untreated fibers or both.

When tissue tissues are formed from a stratified fiber supply in order to form the layers fibrous within the tissue as previously described, the softening agent, for example, may be contained in one or more of the outer layers of the fabric. For example, in a three-layer fabric, the softening agent may be contained in one or both outer layers.

The tissue products made in accordance with the present invention can comprise single-fold products or multi-fold products. For example, the tissue products according to the present invention can contain two folds or three folds. When it contains multiple folds, the softening agent may be present in the outer folds in order to make the softening agent available to the exterior surfaces of the product.

In addition to the tissue products, the absorbent articles can also be produced in accordance with the present invention which contain a fibrous layer that includes the cellulose fibers treated with polysiloxane. The absorbent articles may include, for example, diapers, incontinence products, napkins for women, and products of wet cleansing wipes. Diapers, for example, typically include an absorbent structure placed between a cover layer and a liner. The absorbent structure may contain the treated cellulosic fibers made in accordance with the present invention.

When the absorbent articles are formed as described above, the fibrous layer made in accordance with the present invention may comprise a layer formed with air. Air-formed layers typically contain cellulose fibers in the pulp fluff form. The pulp fluff can be pretreated with the softening agent. According to the present invention, the softening agent can then be reactivated with the retention agent according to any of the methods described above.

When the products are formed in accordance with the present invention, various optional chemical additives can be incorporated into the product as desired. The following materials are included as examples of additional chemicals that can be applied to the fabric containing the kicked fibers 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 process to make the tissue.

Additional types of chemicals that can be added to the fibers for other benefits include, but are not limited to, absorbency aids usually in the form of plasticizers and wetting agents, nonionic, or anionic and cationic surfactants such as polyethylene glycols. lower molecular weight and polyhydroxy compounds such as glycerin and propylene glycol.

Materials that provide skin health benefits such as mineral oil, aloe extract, vitamin E, lotions 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 of known materials and chemicals that are not antagonistic to their intended use. Examples of such materials include, but are not limited to, odor controlling agents, such as odor absorbers, activated carbon fibers and particles, baby talc, sodium bicarbonate, chelating agents, zeolites, perfumes or other agents that mask odor, cyclodextrin compounds, oxidants, and the like. Superabsorbent particles, synthetic fibers, or films can also be employed. Additional options include cationic dyes, optical brighteners, humectants, emollients and the like.

The present invention can be better understood with respect to the following examples.

Eg emplos The following test methods that were used in the present examples.

Preparation of Pulp Aguada Paste To prepare pulp pulp, 24 grams (dry oven base) of pulp fibers were submerged in 2 liters of deionized water for 5 minutes. The pulp slurry was disintegrated for 5 minutes in a British disintegrator. The water paste was then diluted with water to a volume of 8 liters. The chemical additives were then added to the watery paste. The slurry was mixed with a standard mechanical mixer at moderate mixing for 5 minutes after the addition of the chemical additives.

Preparation of hand sheets The leaves for the hands were made with a base weight of 60 grams per square meter (gsm). During the formation of the hand sheet, the appropriate amount of fiber slurry (0.3% consistency) required to make a sheet of 60 grams per square meter was measured in a graduated cylinder. The slurry was then emptied from the graduated cylinder into an 8.5-inch 8.5-inch valley hand sheet mold (Valley Laboratory Equipment, Voith, Inc.) that has been previously filled in at the appropriate level with Water. After pouring the slurry into the mold, the mold was then completely filled with water, which includes the water used to rinse the graduated cylinder. The watery paste was then gently stirred, in a standard perforated mixer plate that was inserted into the slurry and moved up and down seven times, and then removed. The water was then drained from the mold through a set of wire at the bottom of the mold that retained the fibers to form an embryonic tissue. The forming wire was a 90 mesh stainless steel wire cloth. The fabric was laid down from the wire mold with two blotting papers placed on top of the fabric with the soft side of the blotting paper contacting the fabric. The blotting papers were removed and the embryonic tissue was lifted with the lower blotting paper, to which it was attached. The lower blotting paper was separated from the other blotting paper, keeping the embryo tissue attached to the lower blotting paper. The blotting paper was placed with the embryonic tissue face up, and the blotting paper was placed on top of the other two dry blotting papers. Two more dry blotting papers were also placed on top of the embryonic tissue. The stack of blotting papers with the embryonic tissue was placed in a Valley hydraulic press and pressed for one minute at 100 pounds per square inch applied to the tissue. The pressed fabric was removed from the blotting papers and placed in a Valley steam dryer that contains steam at 2.5 pounds per square inch over atmospheric pressure and heated by 2 minutes, with the surface of the wire side of the fabric next to the metal drying surface and a felt under tension on the opposite side of the fabric. Felt tension was provided by a 17.5 pound weight by sliding down on one end of the felt extending beyond the edge of the curved metal dryer surface. The dry handsheet was cut to 7.5 square inches with a paper carrier and then weighed on a heated scale with the temperature maintained at 105 ° C to obtain the dry weight of the oven the tissue. The leaves for the hands were then subjected to the humidity and dry stress test.

Stress Test Unless otherwise specified, tensile strengths are measured in accordance with the Tappi T 494 om-88 Test Method for tissue, modified in that the tension tester is used to have a 3-inch jaw width. , a jaw distance of 4 inches, and a crosshead speed of 10 inches per minute. Moisture resistance is measured in the same way as the dry strength except that the tissue sample is bent without folding around the midline of the sample, held at the ends, and immersed in deionized water for about 0.5 seconds at a depth of about 0.5 centimeters to wet the central part of the sample, in which the region moistened is touched for about 1 second against an absorbent towel to remove excess fluid droplets, and the sample is unfolded and accommodated in the jaws of the voltage tester and immediately tested. The sample is conditioned under TAPPI conditions (50% RH, 22.7 degrees C) before being tested. Generally 5 samples are combined for the wet tension test to ensure that the reading of the load cell is in an exact range.

Resistance to stress The tensile strength of the tissue was reported as "GMT" (grams per 3 inches of a sample), which is the tensile strength of geometric mean and is calculated as the square root of the product of the resistance the tension in the machine direction (MD) and the tensile strength in the cross machine direction (CD). The tensile strengths in the cross machine direction and in the machine direction were determined using an MTS / Sintech voltage tester (available from MTS Systems Corp., Eden Prairie, Minnesota). The tissue samples measured 3 inches in width and were cut in both directions of machine and cross machine. For each test, a sample strip was placed on the jaws of the tester, and adjusted to a calibration length of 4 inches for the facial tissue and a calibration length of 2 inches for the tissue for the bath. The crosshead speed during the test was 10 inches per minute. The tester was connected to a computer loaded with the data acquisition system; for example, the TS TestWork for the Windows computation program. The readings were taken directly from a computer screen reading at the point of rupture to obtain the tensile strength of an individual sample.

Tension index (TI) is a measurement of the resistance the normalized tension for the base weight of the fabric tested in both wet and dry states. The tensile strength can be converted to the stress index by converting the tensile strength determined in units of grams of force by 3 inches to units of Newtons per meter and dividing the result by the basis weight in grams per square meter of the tissue, to give the tension index in Newton-meters per gram (Nm (g).

Ratio of Wet / Dry Stress Index (% IT) Wet / Dry) is the wet tension index divided by the dry stress index multiplied by 100.

Elastic modulus E (kgf) is the elastic modulus determined in the dry state is expressed in unit of kilograms of force. Tappi conditioned samples with a width of 3 inches are placed in the tension tester jaws at a length of caliber (extension between the jaws) of 2 inches. The jaws move and separate at a crosshead speed of 25.4 centimeters per minute and the tilt is taken as the least square fit of the data between the tension values of 50 grams of force and 100 grams of force, or the adjustment of Squares lower the data between the stress values of 100 grams of force and 200 grams of force, whichever is greater. If the sample is too weak to sustain a tension of at least 200 grams of force without failure, an additional layer is added repeatedly until the multiple layer sample can withstand at least 200 grams of force without failure.

Escaras In order to determine the abrasion resistance to the tendency of the fibers to be treated from the fabric when handled, each sample was measured by subjecting the test specimens to abrasion by the following method. This test measures the resistance of the tissue material to the abrasive action when the material is subjected to a horizontally reciprocating surface abrasion device. All samples are conditioned at 23 ° C +/- 1 ° C and 50% +/- 2% relative humidity for a minimum of 4 hours. The test equipment was also shown and described in the United States of America patent number 6,752,905.

The abrasive spindle contained a 0.5"diameter stainless steel rod with the abrasive part consisting of a 0.005" deep diamond pattern extending 4.25"longitudinally around the full circumference of the rod. perpendicular to the face of the instrument so that the abrasive part of the rod extends outwards at full distance from the face of the instrument.The guide pins with magnetic clamps are located on each side of the spindle, one mobile and one fixed, spaced and separated by 4"inches and centered around the bone. This movable clamp and the guide pins were slidably left in the vertical direction, the weight of the jaw provided means to ensure a constant tension of the sample on the surface of the spindle.

Using a matrix press with a die cutter, the specimens were cut into strips 3"+/- 0.05" wide by 8"long with two holes at each end of the specimen. of the machine corresponds to the longest dimension.Each test strip was then weighed to the nearest 0.1 milligrams.Each end of the sample slid over the guide pins and the magnetic clamps held the sheet in place. Movable jaw was then left to vary providing a constant tension through the spindle.

The spindle was then moved back and forth at an angle of approximately 15 degrees from the vertical center line centered on a reciprocal horizontal movement against the test strip for 40 cycles (each cycle is a back and forth stroke) , at a speed of 80 cycles per minute, removing loose fibers from the surface of the fabric. Additionally, the spindle rotated from right to left (when viewed in front of the instrument) at a speed of approximately 5 revolutions per minute. The magnetic clamp was then removed from the sample and the sample was slid out of the guide pins and any loose fiber on the sample surface is removed by blowing compressed air (approximately 5-10 pounds per square inch) onto the sample. proof. The test sample was then weighed to the nearest 0.1 milligrams and the weight loss is calculated. Ten test samples per tissue sample were tested and the average weight loss value in milligrams was recorded.

Total wetting time A drop of distilled water of 50 L was placed on a tissue placed on a flat glass surface, and the time required for the drop to completely disappear was measured. The total wetting time reported is the average of 5 measurements. Before the measurement, the tissue is balanced at least 4 hours at 25 ° C and 50% relative humidity.

Silicone Retention by GC BF3 The contents of the siloxane compound in the samples were measured by gas chromatography after derivatization with boron trifluoride diethyl etarate. The procedure starts by measuring 0.1000 ± 0.0010 grams of cellulose sample containing the siloxane compound at about 0.1 milligrams in containers of 20 mL of upper space. 100 μ? Of boron trifluoride diethyl ethalate are added to the container. After reacting for one hour, the upper space of the vessel is analyzed for Me2SiF2 by gas chromatography (GC). The GC system used is a Hewlett-Packard Model 5890 with a Hewlett-Parckard 7964 auto-sampler and the flame ionization detector. A GSQ column (30 m X 0.53 mm i.d.) was used, available from J &W Scientific (Catalog number # 115-3432). The GC system used helium, the carrier gas at a flow rate of 16.0 mL through the column and 14 mL constitutes in the detector. The temperature of the injector was 150 ° C and the temperature of the detector was 220 ° C. The chromatography conditions were 50 ° C per minute with a ramp of 10 ° C / minute at 150 ° C. This final temperature was sustained for 5 minutes. The retention time for dimethyl-difluoride-silicon was 7 minutes.

The calibration samples were prepared by treating the control samples with a known amount of siloxane sample. A suitable solvent was used to make a dilute solution of the siloxane compound. This solvent was then removed before the derivation by heating in an oven. Calibration supports were used to prepare a linear adjustment of siloxane amount against the peak area of GC detector analyte. This curve was then used to determine the amount of analyte in the unknown sample, which was then converted into an aggregate percent siloxane compound by dividing by the weight of the tissue.

Example 1 A soft and durable creped tissue made of previously treated fibers of reactive silicone was reacted with an amine-containing polymer used as a retention agent.

A dry lap fiber fabric was made to a basis weight of 180 grams per square meter (dry basis) and dried to a solids content varying from 75% to 100% by mixing 90% (by weight) of Aracruz eucalyptus mixed with 10% softwood fibers. A cured epoxy end silicone, Sipell RE 35 F or an IM86 silicon anhydride, both obtained from Wacker Chemical Company, was coteada on this laboratory of dry fiber after the phase of drying to a dose of 10.8 kilograms Silicone / Ton of fibers. The pre-treated silicone dry coating was aged for at least a week at room temperature.

A series of facial base sheets in creped layers were made with 32.5% eucalyptus / 35% softwood fibers / 32.5% eucalyptus fibers divided at a basis weight of 15.6 grams per m2. The fibers previously treated with reactive silicone, when present, were mixed 50% with untreated eucalyptus fibers in the outer layers of tissue. To some samples was added a softening agent, Prosoft TQ-1003 from Hercules, Wilmington at 1 kg / T in the outer layers of tissue. The Kymene, obtained from Hercules, Wilmington, Delaware, was added at 2Kg / T in all tissue layers, which comprises a polyamide-polyamine resin, epichlorohydrin. Parez NC 631, a glyoxylated polyacrylamide obtained from Cytec Industries (West Paterson, New Jersey) was added at 0.9 kg / T in the medium tissue layer. Two layers of tissue were calendered and folded before the test.

Sample 1 was produced without any reactive silicone additive but with the retention agents.

Sample 2 was produced without any additive from reactive silicone but with the addition of Prosoft TQ-1003 and retention agents.

Sample 3 was produced with reactive endcapped silicone treated treated fibers blended in the outer layers reacted with the retention agent.

Sample 4 was made with treated fibers of reactive anhydride silicone mixed in the outer layers reacted with the retention agent.

The samples were tested for the facial tissue properties made with pretreated silicone fibers and the wet end addition of amine-containing polymers used as retention agents. The test was done on the properties of tension, bedsores and total wetting time. The following results were obtained: As shown above, the tissue products made according to the present invention exhibited decreased eschar relative to the control samples while maintaining a comparable strength. As shown above, sample 3 made in accordance with the present invention also exhibited superior wet strength compared to controls.

Example 2 The hand sheets were constructed with pre-treated fibers of functionalized silicone reacted with a retention agent and tested for silicone retention, tension index, total wetting time, bedsores, wet / dry tension index (%), elastic modulus and wet tension index.

A dried eucalyptus coating pulp sheet available from Aracruz, Brazil, was previously treated with 1% (by weight) of functionalized silicone and aged 48 hours at ambient conditions. The hand sheets were constructed using the standard method described above. The retention agents were incorporated into the leaves of hands. In particular, the polyelectrolytes, containing amine such as KYMENE 6500 (polyamide-polyamine-epichlorohydrin resin), obtained from Hercules of Wilmington, Delaware ("Kymene") and CATIOFAST VFH (polyvinylamine) obtained from BASF, Ludwigshafen, Germany ("PVam"), were used at the wet end at 5 Kg / T. The polymers were mixed 5 minutes with the coarse supply (50 grams fibers in 8 L water) before making the sheet of hands. In some cases, additional heat was provided by submitting the hand sheets 30 seconds at 160 ° using air drying (TAD).

The handsheets were measured in tension (wet and dry) and the retention of silicone was analyzed by chromatography techniques (GC GF3), both methods described above. The pulp fibers were pretreated with 4 reactive silicones, all obtained from Wacker Chemical Corporation.

Samples 5-9 were not previously treated with reactive silicones.

Samples 10-13 were pretreated with Sipell RE 35F, an end-capped epoxy silicone. Samples 14-17 were previously treated with Sipell RE 63F, a silicone with epoxy functionalities in the column.

Samples 18-21 were previously treated with IM-86, an anhydrous silicone.

Samples 22-24 were pretreated with 22254 VP, an epoxy-glycol modified silicone oil.

The following results were obtained: Curing: Heating 30S @ 160C in a dryer through air.

As shown above, the retention of the softening agent in the samples drastically improved when the retention agent was added. For example, when a retention agent was present, the retention of the softening agent increased by at least 10% and in some cases by almost 300%. The samples made according to this invention also had a relatively low eschar, a relatively high wet tensile strength and a relatively high dry to wet tensile strength ratio.

Example 3 The effect of wet end chemistry on the retention of WetSoft CTW silicone (containing amine functional groups) was tested.

The standard handsheets were constructed from eucalyptus pulp not treated and previously treated. The untreated eucalyptus pulp was disintegrated for 1 minute in a disintegrated British pulp (BPD) at a specific pH. Then, the WetSoft CTW silicone obtained from Wacker Chemical Corporation was added to 1.1% (weight) on the dried pulp at the BPD contents. The disintegration was then completed (4 minutes more) and the handsheets were made for the physical and silicone retention test. The previously treated WetSoft CTW pulp (SiPP-2) made from Aracruz, from Brazil, was disintegrated in a similar manner and 2 kilograms / T of PAREZ was added as a retention agent to the British pulp disintegrator after 1 minute at a pH dice.

Sample 25 was made from eucalyptus pulp without any reactive silicon additive and without pH control.

Sample 26 was made with eucalyptus pulp and the CTW was added in the British pulp disintegrator at a pH range of 3.5 to 4.

Sample 27 was made with eucalyptus pulp and the CTW was added in the British pulp disintegrator at a pH of 7.5.

Sample 28 was made with the previously treated WetSoft CTW SiPP-2 pulp and contained no PAREZ retention agent.

Sample 29 was made with pre-treated WestSoft CTW SiPP-2 pulp and 2 kilograms / mt of PAREZ retention agent were added at a pH of 4.

Sample 30 was made with previously treated Westsoft CTW SiPP-2 pulp and 2 kgs / mt of PAREZ retention agent were added at a pH of 7.3.

The following results were obtained: As shown above, the sample 29 made according to the present invention significantly improved the wet retention of the functionalized polysiloxane. As shown by comparing sample 29 to sample 30, retention of polysiloxane was somewhat sensitive to pH. The superior retention was achieved at a pH of 4 compared to a pH of more than 7.

These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various 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 there is no attempt to limit the invention heretofore described in such appended claims.

Claims (22)

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

1. A fibrous product comprising. at least one fibrous tissue containing cellulosic fibers, at least a portion of the cellulosic fibers having been treated with a softening agent comprising polysiloxane containing a plurality of first functional groups; Y a retention agent contained in the fibrous tissue, the retention agent comprises a polymer that contains a plurality of a second functional group, the second functional group comprises an amine group, an amide group, an anhydride group, an aldehyde group, a group Epoxy, an epihalohydrin group, or mixtures thereof, the retention agent being present in an amount sufficient to increase the retention of the polysiloxane on the cellulosic fibers under aqueous conditions.

2. A fibrous product as claimed in clause 1, characterized in that the first functional groups contained in the polysiloxane comprise epoxy groups, anhydride groups, amine groups, aldehyde groups, carboxyl groups, epihalohydrin groups, or mixtures thereof.

3. A fibrous product as claimed in clause 1, characterized in that the first functional groups contained on the polysiloxane comprise epoxy groups or anhydride groups wherein the second functional groups contained on the retention agent comprise amine groups.

4. A fibrous product as claimed in clause 1, characterized in that the first functional groups contained on the polysiloxane comprise amine groups and wherein the second functional groups contained on the retention agent comprise amine groups.

5. A fibrous product as claimed in clause 1, characterized in that the first functional groups contained on the polysiloxane comprise epoxy groups, anhydride groups, or carboxylic groups, and wherein the retention agent comprises a glyoxylated polyacrylamide resin, a resin of polyamide-polyamine-epichlorohydrin, a polyethyleneimine resin, a polyvinylamine resin, a copolymer of any of the foregoing or mixtures thereof.

6. A fibrous product as claimed in clauses 1, 2, 3, 4 or 5, characterized in that the retention agent is present in an amount sufficient to increase the retention of the polysiloxane to the cellulosic fibers at least 100%, such as at least 200%, under aqueous conditions.

7. A fibrous product as claimed in any one of the preceding clauses, characterized in that the polysiloxane contains a plurality of third functional groups in addition to the first functional groups.

8. A fibrous product as claimed in clause 7, characterized in that the third functional group is different from the first functional group and comprises a material selected from the group consisting of epoxy groups, anhydride groups, amine groups, aldehyde groups, carboxylic groups, epihalohydrin groups, vinyl groups, ether groups, imine groups and amide groups.

9. A fibrous product as claimed in any one of the preceding clauses, characterized in that the fibrous product comprises a facial tissue having a basis weight of from about 10 grams per square meter to about 100 grams per square meter.

10. A fibrous product as claimed in any one of the preceding clauses, characterized in that the fibrous fabric has a total wetting time of less than about 100 seconds.

11. A fibrous product as claimed in any one of the preceding clauses, characterized in that the fibrous tissue includes at least two fibrous layers, the treated cellulosic fibers being contained in at least one outer layer.

12. A fibrous product as claimed in any one of the preceding clauses, characterized in that the cellulosic fibers have been previously treated with the softening agent.

13. A fibrous product as claimed in any one of clauses 1 to 11, characterized in that the retention agent was applied topically to the fibrous tissue while the fibrous tissue was moist.

14. A fibrous product as claimed in any one of clauses 1 to 11, characterized in that the retention agent was combined with an aqueous suspension of the cellulosic fibers treated during the formation of the fibrous tissue.

15. A fibrous product as claimed in any one of the preceding clauses, characterized in that the fibrous tissue comprises a creped tissue, a tissue dried through non-creped air or a fabric placed by air

16. A fibrous product as claimed in any one of the preceding clauses, characterized in that the fibrous product comprises a multiple layer product.

17. A fibrous product as claimed in any one of the preceding clauses, characterized in that the diaper includes an outer cover and an inner lining, the fibrous fabric being placed between the outer cover and the inner liner.

18. A product for adult incontinence that incorporates the fibrous tissue defined in any of the preceding clauses.

19. A diaper as claimed in clause 17, characterized in that the fibrous tissue is contained in an absorbent structure, the absorbent structure comprises super absorbent particles.

20. A process for producing a fibrous product comprising: forming an aqueous suspension of cellulosic fibers, at least a part of the cellulosic fibers having been treated with a softening agent comprising a polysiloxane containing a plurality of a first functional group; depositing the aqueous suspension on a forming fabric to form a wet fibrous tissue; incorporating into the wet fibrous tissue a retention agent comprising a polymer containing a plurality of a second functional group, the second functional group comprises an amine group, an amide group, an anhydride group, an aldehyde group, an epoxy group, a group epihalohydrin or mixtures thereof; subjecting the wet fibrous tissue to a source of energy in an amount sufficient to cause the retention agent to associate with the polysiloxane; Y Dry the fibrous tissue.

21. A method ta 1 and as claimed in clause 20, characterized in that the first functional groups contained on the polysiloxane comprise epoxy groups, or anhydride groups and wherein the second functional groups contained on the retention agent comprise amine groups.

22. A method as claimed in clause 20, characterized in that the first functional groups contained on the polysiloxane comprise amine groups and wherein the second functional groups contained on the retention agent comprise amine groups. SUMMARY Fibrous products containing a durable softening agent are described. The softening agent generally comprises a polysiloxane containing a plurality of first functional groups. In order to improve the wet retention of the softening agent on the cellulose fibers, the softening agent is reacted with a retention agent. The retention agent generally comprises a cationic polymer having a second functional group. In one embodiment, for example, the softening agent contains epoxy groups or anhydride groups, while the holding agent contains amine groups. The products that can be made according to the present invention include tissue products, wipes and other absorbent articles.