CZ321395A3 - Substantially anhydrous self-emulsifiable chemical softening agent and water dispersion containing thereof - Google Patents

Abstract

Substantially waterless self-emulsifiable chemical softening compositions are provided comprising a mixture of a quaternary ammonium compound and a polyhydroxy compound. Preferred quaternary ammonium compounds include dialkyl dimethyl ammonium salts such as di(hydrogenated)tallow dimethyl ammonium chloride, di(hydrogenated)tallow dimethyl ammonium methyl sulfate. Preferred polyhydroxy compounds are selected from the group consisting of glycerol, polyglycerols having a weight average molecular weight of from about 150 to about 800 and polyoxyethylene glycols and polyoxypropylene glycols having a weight average molecular weight from about 200 to 4,000. The substantially waterless self-emulsifiable chemical softening compositions are prepared by mixing the quaternary ammonium compound with the polyhydroxy compound at a specific temperature range wherein the polyhydroxy compound is miscible with the quaternary ammonium compound. The resulting stable solid or concentrated fluid mixture can then be economically shipped to the consumer or ultimate user. The ultimate users of the chemical softening composition simply dilute the mixture with a liquid carrier (e.g., water) to form an aqueous dispersion suitable for treating fibrous cellulosic materials. The substantially waterless self-emulsifiable chemical softening compositions disclosed herein are primarily intended for softening disposable paper products such as tissues and towels.

Description

Technical field

The present invention relates to a substantially anhydrous self-emulsifying chemical softening composition and an aqueous dispersion therewith. More particularly, the present invention relates to substantially anhydrous, self-emulsifying softening compositions used to process fibrous cellulosic materials, such as tissue paper webs. The treated silk webs can be used to produce soft absorbent paper products such as towels, napkins, tissue paper and tissue products.

BACKGROUND OF THE INVENTION

Paper strips or sheets, sometimes also called fine or silk strips or sheets, are widely used in modern society. Items such as paper towels, napkins, make-up and toilet tissue are common business items. For a long time, it has been known that the three important physical properties of these products are their softness, their absorbency, especially their absorbency in aqueous systems, and their strength, especially wet strength. Research and development efforts have been made to improve each of these properties, while not seriously affecting other properties, while simultaneously improving two or three of these properties.

Softness is the tactile feeling a customer has when holding a product, rubbing it against his skin, or squeezing it with his hand. This tactile feeling is a combination of several physical properties. The rigidity of the paper web from which the products are made is generally considered by one of ordinary skill in the art to be one of the most important physical properties associated with softness. Stiffness is considered to be directly dependent on the dry tensile strength of the web and the stiffness of the fibers that make up the web.

Strength is the ability of the product and thus of the strips to maintain physical integrity and to resist rupture, cracking and tearing under conditions of use, particularly when wet.

. Absorbability is a measure of the ability of the product and of the sheets of the product to absorb a quantity of liquid, especially aqueous solutions or dispersions. Total absorbability, as understood by the customer, is generally considered to be a combination of the total amount of liquid that a given tissue tissue weight absorbs to saturation and the rate at which that liquid absorbs liquid.

The use of resins that increase the wet strength of a paper web is widely known. For example, Westfelt describes numerous such materials and their chemistry is discussed in Cellulose Chemistry and Technology 13, 813 (1979). Freimark et al., U.S. Pat. No. 3,755,220, issued August 28, 1973, mentions that some chemical additives, known as release agents, interfere with the natural fiber-to-fiber bond that occurs during sheet formation in papermaking. . This reduction in binding results in a softer or less coarse sheet of paper. Freimark et al. further disclose the use of wet strength resins together with the use of release agents to eliminate the undesirable effects of such release agents. These release agents reduce both the dry tensile strength and the wet tensile strength.

Shaw in U.S. Patent No. 3,821,068, issued June 28, 1974, also discloses that chemical separating agents can be used to reduce stiffness and thus increase the softness of a roll of fine paper.

Chemical release agents are described in various references, such as US Patent No. 3,554,862 to Hervey et al. of January 12, 1971. These materials include quaternary ammonium salts such as cocotrimethylammonium chloride, oleyltrimethylammonium chloride, di (hydrogenated) tallow dimethyl ammonium chloride, and stearyltrimethylammonium chloride.

Emanuelsson et al. U.S. Pat. No. 4,144,122, issued March 13, 1979, discloses the use of complex quaternary ammonium compounds such as bis (alkoxy (2-hydroxy) propylene) quaternary ammonium chlorides to soften paper webs. These authors also attempt to overcome any decrease in absorbency caused by the separating agents using nonionic surfactants such as adducts of fatty alcohols with ethylene oxide and propylene oxide.

Armak Company, Chicago, Illinois, in their bulletin 76-17 (1977) disclose the use of dimethyl (dihydrogenated) tallow ammonium chloride in combination with fatty acid esters of polyethylene glycols to achieve both softness and absorbency of tissue paper webs.

One example of the results of research to improve paper webs is described in U.S. Patent No. 3,307,746 to Sanford and Sisson on January 31, 1967. Despite the high quality of paper webs produced in the manner described in this patent and despite the commercial success of products made from these webs, research efforts to find improved products.

For example, Becker et al. U.S. Pat. No. 4,158,594, issued January 19, 1979, discloses a method of making a rigid, soft fiber sheet. In more detail, they disclose that the strength of a tissue paper web (which can be softened by the addition of chemical release agents) can increase adhesion during the process of manufacturing one surface of the web to a crepe surface of finely shaped bonding material (such as an acrylic latex emulsion, water soluble resin or elastomeric bonding). material) which adheres to one surface of the strip and to the creped surface of the finely shaped embodiment, and so the roll on the creping surface is creped to produce sheet-like material.

Conventional quaternary ammonium compounds, such as the well-known dialkyldimethylammonium salts (e.g., dilute dimethylammonium chloride, dilute dimethylammonium methyl sulfate, di (hydrogenated) tallow dimethylammonium chloride, etc. ...) are effective chemical separating agents. Unfortunately, these quaternary ammonium compounds are not hydrophilic. Applicants have discovered that the chemical softening compositions of the present invention increase both the softness and the rate of absorption of fibrous cellulosic materials.

Obtaining chemical softening compositions containing these softening compounds in substantially anhydrous forms leads to cost savings on shipping the product (less weight), savings in packaging material and savings on the equipment required to produce chemical softening agents (less equipment required to produce aqueous dispersions) . Furthermore, the present invention also provides environmental safety benefits by removing organic solvents, particularly volatile organic solvents typically used in the preparation of concentrated plasticizers.

It is an object of the present invention to provide a substantially anhydrous self-emulsifiable chemical softening composition useful for processing fibrous cellulosic materials.

It is a further object of the present invention to provide soft, absorbent tissue paper products.

It is a further object of the present invention to provide a process for the manufacture of soft alabble tissue paper products.

These and other objects obtainable using the present invention will become apparent upon reading the following description.

SUMMARY OF THE INVENTION

The present invention provides a substantially anhydrous self-emulsifiable chemical softening composition useful for processing fibrous cellulosic materials. Briefly, the anhydrous self-emulsifiable chemical softening composition comprises a composition

a) quaternary ammonium compounds of the general formula I

R ₂ l

R ₂ - N ⁺ - R Χ '(I)

AND

R x wherein each R ₂ is C 1 -C 6 alkyl, C 1 -C 6 hydroxyalkyl, or a mixture thereof, each R _x is C 14 -C 22 hydrocarbon or a mixture thereof, and X - is suitable anion, a

b) a polyhydroxy compound selected from the group consisting of glycerol, polyglycerols having a weight average molecular weight of 150 to 800 and polyoxyethylene glycols and polyoxypropylene glycols having a weight average molecular weight of 200 to 4000, wherein the ratio of the weight of the quaternary ammonium compound to the polyhydroxy compound is 1: 0.1 to 0.1: 1 and the polyhydroxy compound is miscible with the quaternary ammonium compound at a temperature of at least 40 ° C. The chemical softening composition of the present invention is a stable, homogeneous, solid or viscous liquid at a temperature of greater than 20 ° C. The liquid may have either a liquid or liquid crystal structure. The moisture content of the substantially self-emulsifiable chemical softener composition is less than 20 wt%, preferably the moisture content of the chemical softener composition is less than 10 wt%. and more preferably, the moisture content of the chemical softening composition is less than 5 wt.

Examples of quaternary ammonium compounds suitable for use in the present invention include the well-known dialkyldimethylammonium salts, such as di-dimethylammonium chloride (DTDMAC), di-dimethylammonium methylsulfate (DTDMAMS), di (hydrogenated) tallow dimethylammonium ethylsulfate (DHTDMAMS) and di (hydrogenated) 1 (hydrogenated) .

Examples of polyhydroxy compounds useful in the present invention include glycerol, polyglycerols having a weight average molecular weight of from 150 to 800, and polyoxyethylene glycols having a weight average molecular weight of from 200 to 4000, preferred are polyoxyethylene glycols having a weight average molecular weight of from 200 to 600.

Briefly, the method of making the silk rolls of the present invention comprises the steps of forming the papermaking material from the above components, depositing the papermaking material on a perforated surface, such as a longitudinal screen of a paper machine, and removing water from the deposited material.

All percentages, ratios and parts are by weight unless otherwise indicated.

The accompanying drawings are briefly described below. While this description, completed by the claims, shows and clearly claims the invention, it is believed that the invention will be better understood from the following description, together with the accompanying drawings.

Figure 1 are phase diagrams of dioctadecyldimethylammonium methylsulfate (DODMAMS) and DHTDMAMS.

Figure 2 is a phase diagram of the DODMAMS / PEG-400 system.

Figure 3 is a cryotransmission photomicrograph at a magnification of 63,000 x 2% (w / w) of the dispersion produced by diluting a solid premix of the DHTDMAMS and PEG-400 system in a 1: 1 weight ratio.

Figure 4 is a cryotransmission photomicrograph at a magnification of 63,000 x 2% (w / w) of the dispersion formed by diluting the DHTDMAMS-PEG-400 liquid premix in a 1: 1 weight ratio.

Figure 5 is a cryotransmission photomicrograph at a magnification of 63,000 x 2% (w / w) of the dispersion produced by diluting the DHTDMAC liquid premix and glycerol with PEG-400 in a 1: 1 weight ratio.

The present invention is described in more detail below.

Ί

Although this specification ends with claims that detail and clearly claim the subject matter of the invention, it is believed that the invention can be better understood by reading the following detailed description and the appended examples.

The term viscous liquid, as used herein, refers to a liquid having a viscosity greater than or equal to 10,000 centipoise at 20 ° C.

The term homogeneous mixture as used herein means compositions in which the quaternary ammonium and polyhydroxy compounds are dissolved or dispersed with each other.

The term self-emulsifiable as used herein means compositions that form a uniform colloidal dispersion with minimal use of shear, heat, dispersants, etc. when added to a liquid carrier such as water.

The terms tissue web or roll, paper web or roll, web or roll, paper sheet and paper product mean paper sheets produced according to a process comprising the steps of forming an aqueous paper making base, depositing the base on a perforated surface such as a paper machine longitudinal screen. , and removing the water from the base by gravity or vacuum drying, with or without pressure and evaporation.

The term aqueous base for papermaking means aqueous papermaking fibers and the chemicals described herein.

The first step of the process of the present invention is the formation of an aqueous base for papermaking. This base comprises paper-forming fibers (sometimes referred to herein as pulp) and a mixture of at least one quaternary ammonium compound and at least one polyhydroxy compound, which will be described below.

It is envisaged that the pulp in all its forms will normally contain the paper-forming fibers used in the present invention. However, other cellulosic pulp furnishings such as cotton cartons, bagasse pulp, cellulose-based fabric, etc. may not be used and may be used. Pulps used herein include chemical pulps such as kraft pulp, sulphite and sulphate pulp as well as mechanical pulp, including, for example, pulp, thermomechanical pulp, and chemically modified thermomechanical paper (CTMP). Pulp from both deciduous and coniferous trees may be used. Recycled paper fibers, which may contain any or all of the above categories, as well as non-fibrous materials such as fillers and adhesive components, which have been used to facilitate the manufacture of the original paper, are also useful in the present invention. Preferably, according to the present invention, papermaking fibers comprising kraft pulp derived from Nordic softwoods are used.

The present invention comprises as an essential component a mixture of a quaternary ammonium compound and a polyhydroxy compound. The ratio of quaternary ammonium compound to polyhydroxy compound is from 1: 0.1 to 0.1: 1, preferably the weight ratio of quaternary ammonium compound to polyhydroxy compound is 1: 0.3 to 0.3: 1, more preferably the weight ratio of quaternary ammonium compound to polyhydroxy compound 1: 0.7 to 0.7: 1, although this ratio varies according to the molecular weight of the respective polyhydroxy compound and / or quaternary ammonium compound used.

All these types of compounds will be described in detail hereinbelow.

The substantially anhydrous self-emulsifiable chemical softener composition comprises, as an essential component, a quaternary ammonium compound of Formula I

R ₂

AND

R ₂ - N * - R _x X - (I).

Rx

In formula (I), each R _x is a C 14 -C 22 hydrocarbon group, preferably a tallow group, R ₂ is a C 1 -C 6 alkyl or hydroxyalkyl group, preferably a C 1 -C 3 alkyl group, X means a suitable anion such as a halide (e.g. chloride or bromide) or methyl sulfate. Tallow, as stated in Swern (ed.): Bailey's Industrial Oil and Fat Products, Third Edition, John Wiley & Sons, New York 1964, is a naturally occurring material having a variable composition. Table 6.13 in the above reference, edited by Swern, indicates that typically 78 or more wt. tallow fatty acids contain 16 or 18 carbon atoms. Typically, half of the fatty acids are present in tallow as unsaturated, primarily as oleic acid. Both synthetic and natural tallow are within the scope of the present invention. _Rx preferably represents an alkyl group having 16 to 18 carbon atoms, most preferably R _x represents an alkyl group having 18 carbon atoms, straight chain. R @ ₂ is preferably methyl and X @ ^- is chloride or methyl sulfate.

Examples of quaternary ammonium compounds suitable for use in the present invention include the well-known dialkyldimethylammonium salts, such as di-sodium dimethylammonium chloride, di-sodium dimethylammonium methyl sulfate, di (hydrogenated) tallow dimethyl ammonium chloride, preferably di (hydrogenated) tallow dimethyl ammonium methyl sulfate. This material is available from Sherex Chemical Copany Inc, Dublin, Ohio, under the tradename Varisoft ^(R) 137.

The chemical softening composition comprises a polyhydroxy compound as an essential component.

Examples of polyhydroxy compounds useful in the present invention include glycerol, polyglycerols having a weight average molecular weight of from 150 to 800 and polyoxyethylene glycols and polyoxypropylene glycols with a weight average diameter of from 200 to 4000, preferably from 200 to 1000, most preferably from 200 to 600. Particularly preferred are polyoxyethylene glycols having a weight average molecular weight of up to 200 to 600. Mixtures of the above-described polyhydroxy compounds may also be used. For example, mixtures of glycerol and polyoxyethylene glycols having a weight average molecular weight of from 200 to 1000, more preferably from 20 to 600, are used according to the invention. The weight ratio of glycerol to polyoxyethylene glycol is preferably from 10: 1 to 1: 10.

A particularly preferred polyhydroxy compound is a polyoxyethylene glycol with a weight average molecular weight of 400. This material is commercially available from Union Carbide Company, Danbury, Connecticut, under the trade name PEG-400.

The anhydrous self-emulsifiable chemical softener composition described above, i.e. a mixture of quaternary ammonium compounds and a polyhydroxy compound, is preferably diluted to the desired concentration so as to form a dispersion of the quaternary compound and polyhydroxy compounds before being added to the aqueous fiber suspension or paper base a papermaking machine at any suitable location of the papermaking machine sieve or at the sheet manufacturing stage. However, the use of the chemical softening composition described above after the production of the wet tissue paper web and prior to drying the web also provides significant softness, absorbency and wet strength and is expressly included within the scope of the present invention.

It has been discovered that a chemical softening composition is more effective when the quaternary ammonium compound and the polyhydroxy compound are first mixed together and then added to the paper making base. A preferred method, which will be described in more detail in Example 1 herein, comprises heating the polyhydroxy compound to a temperature of about 66 ° C, followed by adding the quaternary ammonium compound to the hot polyhydroxy compound. This creates a homogeneous liquid. The weight ratio of the quaternary ammonium compound to the polyhydroxy compound ranges from 1: 0.1 to 0.1: 1, preferably the weight ratio of the quaternary ammonium compound to the compound is 1: 0.3 to 0.3: 1, more preferably the weight ratio the quaternary ammonium compound to this compound is 1: 0.7 to 0.7: 1, although this ratio varies according to the molecular weight of the respective compound used and / or the quaternary ammonium compound. The moisture content of the chemical softener composition is less than 20 wt%, preferably the moisture content of the chemical softener composition is less than 10 wt%, more preferably the moisture content of the chemical softener composition is less than 5 wt%. It is important that the chemical softening composition be a stable, homogeneous, solid or viscous liquid at a temperature above or around 20 ° C.

The substantially anhydrous self-emulsifiable chemical softening composition may be premixed with a chemical supplier (eg, Sherex Company, Dublin, Ohio). Obtaining chemical softening compositions containing these softening compounds in substantially anhydrous forms results in cost savings on shipping the product (less weight), cost savings on the packaging material, and cost savings on chemical softener processing equipment (less equipment is required to produce an aqueous dispersion) ). The present invention also has advantages in terms of environmental safety since it removes organic solvents, especially volatile organic solvents. End users of the chemical softener composition simply dilute the mixture with a liquid carrier (i.e., water). This results in an aqueous dispersion of the quaternary ammonium compound / polyhydroxy compound mixture, which is then added to the paper making base. A homogeneous mixture of the quaternary ammonium compound and the polyhydroxy compound prior to dispersion in an aqueous medium may exist either in a solid state or in a liquid state. Preferably, the quaternary ammonium-1-eno-ene-1-ene mixture is present. The polyhydroxy compound is diluted with a liquid carrier such as water to a concentration of from 0.01 to 25% by weight. a softening composition prior to addition to the paper making base. The temperature of the liquid carrier is preferably in the range of from 20 ° C to 80 ° C. After mixing, the quaternary ammonium compound and the polyhydroxy compound are present as particles dispersed in a liquid carrier. The average particle size is preferably in the range of from 0.01 to 10 μτα, more preferably from 0.1 to 1.0 μτα. As seen in Figures 3 to 5, the dispersed particles are either in the form of closed bags or open portions of particles.

Unexpectedly, it has been found that adsorption of polyhydroxy compound on paper is significantly increased when premixed with a quaternary ammonium compound and added to the paper in the manner described above. In fact, at least 20 wt. polyhydroxy compounds and quaternary ammonium compounds added to fibrous cellulose. The retained amount of the quaternary ammonium compound and the polyhydroxy compound is preferably from 50 to 90% by weight. from the amount added.

It is important that adsorption occurs at a concentration and at a time that is practical for use during papermaking. In an effort to better understand the surprisingly high retention of polyhydroxy compound on paper, the physical properties of the molten solution and the aqueous dispersion of di (hydrogenated) tallow dimethylammonium methyl sulfate (DHTDMAMS) and polyoxyethylene glycol 400 were studied.

Without wishing to be bound by theory or in any way limiting the scope of the present invention, the following discussion is presented, which explains how the quaternary ammonium compound promotes adsorption of the polyhydroxy compound on paper.

Physical state information DHTDMAMS (di (hydrogenated) tallow dimethylammonium methyl sulfate), R ₂ N ⁺ (CH 3) 2, CH 3 SO 3, and DODMAMS were obtained from X-ray spectroscopy and NMR (nuclear magnetic resonance) data of a commercial mixture. DODMAMS (dioktadecyldimethylamoniummethylsulfát, (C18H37) 2N ⁺ (CH3) _{2. 3} .CH ₃ ~ 0S0) is a major component of DHTDMAMS, and serves as a model compound for the commercial mixture. It is useful to consider first a simpler DODMAMS system and then a more complex commercial DHTDMAMS blend.

Depending on the temperature, DODMAMS can exist in any of the four phase states (Figure 1): dual polymorphic crystals (X ^e and X '), lamellar (lam) liquid crystal, or liquid phase. The X ^e crystal exists from a temperature below room temperature to 47 ° C.

At this temperature, it becomes a polyroorphic X 'crystal that passes at 72 ° C to the naphtha of the Lam crystal. This phase becomes an isotropic liquid at 150 ° C. DHTDMAMS is expected to resemble DODMAMS with its physical behavior, except that the phase transition temperatures will be lowered and extended. For example, the transition from X ^e to X 1 crystals occurs at 27 ° C for DHTDMAMS instead of 47 ° C, as is the case with DODMAMS. Also, the calorimetric data show that some transitions of the crystal Lam phase occur more in DHTDMAMS than in DODMAMS. The onset temperature of the highest of these 56 ° C transitions is in good agreement with the X-ray data.

The DODMAC (Dioctadecyldimethylammonium Chloride) report is a qualitatively different behavior from DODMANS in that the Lam liquid crystal phase does not exist in this compound (Laughlin et al .: Physical Sciences of the Dioctadecyldimethylammonium Chloride - Water System.) 1. Equilibrium Phase Behavior in Journal of Physical Chemistry 94 , 2546 (1990), incorporated herein by reference). However, this difference is not expected to be important for the use of this compound (or its commercial analogue DHTDMAC) in paper processing.

A mixture of DHTDMAMS with PEG-400 in a weight ratio of 1: 1 is studied. Figure 2 proposes an acceptable phase behavior model for this system. This diagram shows that DODMAMS and PEG are immiscible at high temperatures. They coexist as two liquid phases at these temperatures. As the mixtures of the two liquids cool in the region, a phase is separated from the Lam mixture. This --study thus shows that ^- these-two-mater ialyg i ^- while immiscible at high temperatures, they are miscible at lower temperatures within the Lam liquid crystal phase. At even lower temperatures, the crystal phases are expected to separate from the Lam phase and the compounds are again immiscible.

Thus, these studies suggest that to form good dispersions of DHTDMAMS with PEG-400 in water, the preformed mixture, which is diluted with water, should be maintained within a temperature range within which both compounds are miscible.

Phase studies of a mixture of DHTDMAC with PEG-400 using a stepwise dilution method show that their physical properties are significantly different from those of DHTDMAMS. No liquid crystal phases were found. These compounds are miscible as a liquid solution over a wide temperature range, indicating that .....

these dispersions can be prepared from these mixtures within a comparable temperature range. In particular, there is no upper limit of miscibility temperature.

Dispersions of any of these materials can be prepared by diluting a previously prepared mixture which is stored at a temperature at which the polyhydroxy compound and the quaternary ammonium salt are miscible with water. It is not so important whether they are miscible as a liquid crystal phase (as in the case of DHTDMAMS) or as a liquid phase (as in the case of DHTDMAC). Neither DHTDMAMS nor DHTDMAC are water soluble, so diluting any dry phase with water precipitates the quaternary ammonium compound as small particles. Both quaternary ammonium compounds will precipitate at elevated temperatures as liquid crystal phases in dilute aqueous solutions, regardless of whether the dry solution was a liquid or a liquid crystal. The polyhydroxy compound is water soluble in any ratio so that it does not precipitate.

Cryoelectron microscopy shows that the particles present in the dispersion have a size of 0.1 to 1.0 μπι and their structure is highly variable. Some are platelets (curved or flat), while others are closed pouches. The membranes of all these particles are bilayered in molecular dimensions, with the front groups facing the water, the tail groups facing each other. PEG is believed to be associated with these particles. The application of the dispersions prepared in this manner to the paper results in the attachment of the quaternary ammonium ion to the paper, strongly promotes adsorption of the polyhydroxy compound to the paper, and produces the desirable increase in softness while maintaining water absorption.

If the above-mentioned dispersions are cooled, partial crystallization of the material within the colloidal particles may occur. Yippee

however, it is likely to reach equilibrium for a long time (possibly months), so membranes that ~ 300soTT ~ within those particles that interact with the paper are in a disordered state.

These bags containing DHTDMAMS and PEG are believed to disintegrate by drying the fibrous cellulosic material. Once the pouch has disintegrated, most of the PEG component can penetrate into the interior of the cellulosic fiber, increasing the flexibility of the fibers. Importantly, a certain amount of PEG is retained on the fiber surface and causes an increase in the absorbency of the cellulosic fibers there. Due to the ionic interactions, most of the DHTDMAMS component remains on the surface of the cellulose fiber where it increases the surface feel and softness of the paper product.

The second step of the process of the present invention is to deposit the paper making base using the chemical softening composition described above as an additive on the perforated surface. The third stage is the removal of water from the deposited base. Methods and apparatuses that can be used in these two stages of manufacture are apparent to those skilled in the paper making art. Preferred embodiments of the tissue paper of the present invention comprise from 0.005 to 5.0, preferably from 0.03 to 0.5% by weight (based on dry fiber) of the chemical softening composition described herein.

The present invention is generally applicable to tissue paper, including, but not limited to, conventionally felt tissue paper, very bulk densified tissue paper, and very bulk non-compact tissue paper. The tissue paper may have a homogeneous or multilayer construction. Thus, products made from tissue paper may have a monolayer or multilayer construction. Fine structures made of laminated paper webs are described in U.S. Patent 3,994,771 to Morgan Jr. et al., issued Nov. 30, 1976, and incorporated herein by reference. Generally, a wet-laid composite, a soft, bulky, and absorbent paper structure is made from two or more base layers, which preferably comprise different types of fibers. These layers are preformed by depositing separate streams of dilute fiber slurries, these fibers typically being relatively long softwood fibers and relatively short hardwood fibers used in tissue paper production on one or more endless perforated screens. These layers are further combined to form a laminated composite web. The laminated web is then adapted to match the surface of the open sieve drying / fabric printing by applying hydrostatic pressure to the web and then thermally pre-drying on the fabric as part of a low density paper making process. The layered web may be laminated such that the fiber type or fiber content of the optional layers may be substantially the same. The tissue paper preferably has a basis weight of between 10 and 65 g / m ² and a density of 0.60 or less g / cm ³ . The basis weight will preferably be below 35 or less g / m ² and a density of 0.30 or less g / cm ³ . The density will most preferably be 0.04 to 0.20 g / cm ³ .

Conventional pressed tissue paper and methods of making such paper are known to those skilled in the art. Such papers are typically produced by placing the paper base on a perforated paper machine screen. This screen is often called the Fourdnier wire in the art. Once the foundation is deposited on a sieve, it is referred to as a belt. Water is removed from this web by transferring it to a dewatering felt, pressing the web, and drying at elevated temperature. Special methods and typical devices for making the strips according to the method just described are well known to those skilled in the art. In a typical method, the base of the low cohesive pulp base is transferred to a pressure headbox. This headbox has an opening for supplying a thin layer of paper stock to the longitudinal screen of the paper machine. This results in a wet belt. Typically, water is removed from this web to a fiber content of 7-25% (of the total weight of the web) by removing water under vacuum and further removing water by pressing while subjecting the web to pressure exerted by counteracting mechanical members, such as rollers.

The dewatered web is then further pressed during movement and dried with jet drum devices known in the art as a Yankee-V drying drum with mechanical means, such as opposed cylindrical drums pressing the web between them, to exert pressure. When pressing the belt with the surface of the Yankee drying drums, the belt can also be exposed to vacuum. A plurality of these Yankee drying drums may be used, and further pressing may optionally be inserted between them. The tissue paper structures produced herein are hereinafter referred to as conventional, pressed, tissue paper structures. These sheets are considered compact because the web is subjected to considerable mechanical compression forces while the fibers are moist and are then dried in a compressed state.

The densified tissue paper assembly is characterized by a relatively large bulk region of relatively low fiber density and a grid of densified zones of relatively high density. The very bulky region can also be described as pillow regions. Thickened zones are sometimes referred to as articulated regions. The thickened zones may be discontinuously located in a very bulky area or may be fully or partially connected to each other in this area. A preferred method of making patterned densified tissue paper is described in U.S. Patent No. 3,301,746 to Sanford and Sisson of January 31, 1967;

No. 974,025 to Peter G. Ayers, Aug. 10, 1976, U.S. Patent No. 5,924,085

No. 191,609 to Paul D. Trokhan of March 4, 1980; and U.S. Patent No. 4,637,859 to Paul D. Trokhan of January 20, 1987. All of these patents are incorporated herein by reference.

In general, the patterned thickened strips are preferably produced by depositing a paper making base on a perforated screen, such as a longitudinal screen of a paper machine. This creates a wet web, which is then placed against the carrier grid. The web is then pressed against the carrier grid, resulting in thickened zones on the web at those points that correspond to the contact points between the carrier web and the wet web. The remainder of the strip which is not compressed during this operation is referred to as a very bulky region. This very large area can be further densified using a hydrostatic pressure such as a vacuum blower or air blower dryer. Water is removed from the web, or the web is pre-dried to substantially bypass the compression of a very voluminous region. This is preferably done by hydrostatic pressure, such as a vacuum blower or dryer by blowing air or else by mechanically pressing the strip against the carrier grid, whereby the very large area is not pressed. Water removal, optionally pre-drying, and densified zone formation operations may be integrated or partially integrated to reduce the overall number of production steps. After formation of the thickened zones, dewatering and possible pre-drying, the web is completely dried, preferably without the use of mechanical pressing. Preferably, from about 8 to 55% of the surface of the tissue paper comprises thickened joints with a relative density of at least 125% of the density of the very bulk region.

The carrier grid is preferably a carrier with an assembly of hinges that, when applied, acts as a carrier grid which facilitates the formation of thickened zones upon application of the pressure. The hinge assembly is given by the carrier grid referred to above. Carriers are described in U.S. Patent No. 3,301,746 to Sanford and Sisson, issued January 31, 1967; U.S. Patent No. 3,821,068 to Salvucci Jr. et al. et al., issued May 21, 1974; U.S. Patent No. 3,974,025 to Ayers et al., issued August 10, 1976; U.S. Patent 3,573,164 to Friedberg et al., issued March 30, 1971; U.S. Patent No. 3,473,576. Amneuse, issued October 21, 1969, U.S. Patent 4,239,065 Trokhan, issued December 16, 1980, and U.S. Patent 4,528,239 Trokhan, issued July 9, 1985. All of these patents are incorporated herein by reference.

Preferably, the papermaking base is first applied as a wet web to a perforated support such as a longitudinal screen of a paper machine. The water is then removed from the belt and transferred to the carrier. The papermaking base can also be first laid on a perforated carrier which also functions as a carrier. Once the wet web is manufactured, water is removed therefrom and preferably heat-dried to a selected fiber content of between 40 and 80 wt%. The removal of water can be carried out in suction boxes or other vacuum devices or in air dryers. A sample of the carrier joints is applied. the belt as above before completely drying the belt. One way to do this is to use mechanical pressure. This can be done, for example, by pressing the gap roller which carries the carrier against the surface of a drying drum, such as a Yankee drying drum, wherein the belt is deposited between the gap roller and the drying drum. Preferably, the web is also placed against the carrier prior to complete drying by applying a hydrostatic pressure with a vacuum device such as a suction box or an air blower dryer. The hydrostatic pressure can be used to impress the densified zones during the initial water removal, in a separate subsequent production step, or combinations thereof.

The structures of uncompacted, unsampled, densified tissue paper are described in U.S. Patent No. 3,812,000 to Joseph L. Salvucci Jr. and Peter N. Yiannos of May 21, 1974; and U.S. Patent No. 4,208,459 to Henry E. Becker, Albert L. McConnell and Richard Schutte of June 17, 1980, both of which are incorporated herein by reference. In general, the structures of the non-compacted, unsampled densified tissue paper are prepared by depositing a paper making base on a perforated manufacturing screen, such as a longitudinal screen of a paper machine. A wet web is formed, water is removed from the web and additional water is removed without mechanical compression until the web has a fiber content of at least 80 wt. and the belt is creped. Water is removed from the strip by vacuum dewatering and heat drying. The resulting structure is a soft but weak • velmir-objTeminý ^ anrch-rietativně ^- uncompacted vIúkenT ^- va'Z'ebný Ma = ^r_ 'rial is preferably applied to parts of the strip prior to creping.

The tissue paper rolls of the present invention can be used in any application where soft, absorbent tissue paper webs are required. Particularly preferred uses of the tissue paper web of the present invention are paper towels, toilet and make-up products. For example, two rolls of tissue paper according to the invention can be rolled and joined together as described in U.S. Patent No. 3,414,459 Wells, issued December 3, 1968, which is incorporated herein by reference, to form two-ply paper towels.

The molecular weight determination will be described in the following. ..........

An essential feature that distinguishes polymeric materials is their molecular size. The properties that allow polymers to be used in various applications derive almost entirely from their macromolecular nature. To fully characterize these materials, it is essential to have some ways of defining and determining their molecular weights and molecular weight distributions. It is more accurate to use the term relative molecular weight than molecular weight, but the latter is more commonly used in polymer technology. It is not always practical to determine molecular weight distributions. However, the use of chromatographic techniques makes this determination more common. Rather, however, molecular size is expressed in terms of molecular weight averages.

If the simple molecular weight distribution is represented by fractions (w _± ) of the masses of molecules having a relative molecular weight (Μ _χ ), several useful average values can be defined. The averaging is based on the number of molecules (N _± ) of the appropriate size (M _± ) giving the number average molecular weight η = Σ Ni.Mi / Σ Ni.

An important consequence of this definition is that the number average molecular weight in grams contains the Avogadro number of the molecules. This definition of molecular weight is consistent with monodisperse molecular particles, i.e. molecules having the same molecular weight. More importantly, if the number of molecules in a given weight of a polydisperse polymer can be determined in some way, then n can easily be calculated.

<·

This is the basis for colligative properties measurement.

The averaging of the mass fractions (W _± ) of molecules of a given mass (Mi) leads to the definition of the number average molecular weight w = Σ Wí.Ní / Σ Wi = Σ Ni.Mi ² / Σ Ni.M _± .

The w value is more useful for expressing the molecular weights of polymers than n because it more accurately reflects properties such as melting viscosity and mechanical properties of the polymers and is thus used in the present invention.

Analysis of the amount of chemicals used in the present invention or retained on the tissue paper strips is performed by any method acceptable in the art.

For example, the amount of quaternary ammonium compound, such as di (hydrogenated) tallow dimethyl ammonium methyl sulfate (DHTDMAMS), retained on tissue paper may be determined by extraction of DHTDMAMS with an organic solvent followed by anionic / cationic titration with dimidium bromide (3,8-diamino-5-methyl-6- phenylphenanthridium bromide) as an indicator. The amount of polyhydroxy compound, such as PEG-400, can be determined by extraction with an aqueous solvent, such as water, followed by gas chromatography or colorimetric determination of the amount of PEG-400 in the extract. These methods are given by way of example and do not mean that other methods that may be useful for determining the amount of the respective constituents retained on the tissue paper are not excluded.

-Hydrofřlnost ^- tissue ^- paper ^- in general ^- is ^- the ability of the tissue paper to be wetted with water. The hydrophilicity of the tissue paper can be partially quantified by determining the time it takes for the dry tissue paper to be completely wetted with water. This is referred to as the wetting time. To ensure that this wetting time test is consistent and repeatable, the following procedure is used to determine the wetting time: first, a modified unit sheet sample is prepared (environmental conditions for testing paper samples are: 23 + 1 ° C and 50 + 2% % relative humidity according to TAPPI Method T 402)

size 11.1 by 12 cm of tissue paper. Secondly, the sheet is folded into four (4) quarters together and crimped into a ball with a diameter of 1.9 cm to 2.5 cm. Third, the ball is placed on the surface of distilled water at 23 ± 1 ° C and the time counted. For

-. the fourth, after the ball has been completely wetted, the sheet of time is stopped and subtracted. Complete wetting is observed visually.

However, the hydrophilic properties of the tissue paper embodiments of the present invention can be determined immediately after manufacture. However, a significant increase in hydrophobicity can occur within the first two weeks after the tissue paper has been manufactured, i.e., after the paper is 2 weeks old from its manufacture. Wetting times are therefore preferably measured at the end of the two weeks. Accordingly, the wetting times measured at the end of the two weeks of aging at room temperature are referred to as two week wetting times.

The density of tissue paper as used herein means the average density calculated on the basis of the weight of the paper divided by calipers with the appropriate unit conversion. The tissue paper caliper as used herein means a paper thickness that is subjected to a pressure of 15.5 g / cm @ 2 ^. .

In addition to the substantially anhydrous self-emulsifying chemical softener composition or paper making base described herein, other chemicals commonly used in papermaking can be added as long as they do not significantly and adversely affect the softening and absorbency of the fibrous material and increase the effect of the chemical softening composition.

For example, surfactants may be used to process the tissue paper web of the present invention. The amount of surfactant, if used, is preferably from 0.01 to 2.0 wt%. based on the dry weight of the tissue paper fibers. The surfactants preferably have alkyl chains of eight or more carbon atoms. Examples of anionic surfactants are linear alkylsulfonates and alkylbenzenesulfonates. Examples of non-ionic surfaces

The active agents are alkyl glycosides, including alkyl glycoside esters such as Crodesta SL-40, which is available from Croda, Inc. (New York, N.Y.), alkyl glycoside ethers are described in U.S. Patent No. 4,011,389 to W. K. Langdon et al. of March 8, 1977 and alkylpolyethoxylated esters such as Pegosperse 200 ML available from Glyco Chemicals, Inc. (Greenwich, Kt.) And IGEPAL RC-520 available from Rhone Poulenc Corporation (Cranbury, N.J.).

Other types of chemicals that may be added include dry-strength additives to increase the tensile strength of the silk webs. Examples of such dry strength additives include carboxymethylcellulose and cationic polymers from the Acco group of chemicals, such as Acco 711 and Acco 514. Acco group chemicals are preferred. These materials are commercially available from the American Cyanamid Company, Wayne, New Jersey. The amount of these dry strength additives is preferably from 0.01 to 1.0% by weight, based on the dry tissue fiber weight.

Other types of chemicals that may be added include dry strength additives to increase the wet tear strength of the silk webs. The present invention may contain, as an optional component, from 0.01 to 3.0, more preferably from 0.3 to 1.5% by weight, based on the weight of the dry fiber, of water-soluble, stable wet strength resins.

The stable wet strength resins used herein may be of a variety of types. Typically, here, the resins are previously known. and which have found use in the field of paper production. Numerous examples are given in the above-mentioned Westfelt work, which is incorporated herein by reference.

Typically, these wet strength resins are water-soluble cationic materials. That is, these resins are water soluble at the time they are added to the paper making base. It is quite possible, and even expected, that subsequent events, such as crosslinking, make these resins insoluble in water. Furthermore, some resins are soluble only under specific conditions, such as a limited pH range.

Wet strength resins are generally believed to undergo crosslinking or other curing reactions upon embedding on, in, or between fibers in papermaking. Crosslinking or curing does not normally occur when substantial amounts of water are present.

Various polyamide-epichlorohydrin resins are particularly useful. These materials are low molecular weight polymers with reactive functional groups such as amine, epoxy and azetidinium groups. The patent literature is filled with descriptions of methods of making such materials. Examples of such patents, which are incorporated herein by reference, are U.S. Patent No. 3,700,623 to Keima of October 24, 1972 and U.S. Patent No. 3,772,076 to Keima of November 13, 1973.

Particularly useful in the present invention are polyamide-epichlorohydrin resins sold under the trademarks Kymene ^(R) 557H and Kymene ^(R) 2064 by Hercules Incorporated, Wilmington, Delaware. These resins are generally described in the above-mentioned Keima patents.

Basically activated polyamide-epichlorohydrin resins useful in the present invention are sold under the trade name Santo Res, such as Santo Res 31, by Monsanto Company in St. Petersburg. St. Louis, Missouri. These types of materials are generally described in U.S. Patent Nos. 3,855,158 Petroviche of December 17, 1974, No. 3,899,388 Petroviche of August 12, 1975, No. 4,129,528 Petroviche of December 12, 1978, No. 4,147,586 Petroviche of 3 April 1979; No. 4,222,921 to Van Eenam on September 16, 1980. All of which are incorporated herein by reference.

Other water-soluble cationic resins useful herein are polyacrylamide resins such as

are those sold under the tradename Stump, such as Stump 631 NC sold by the American Cyanamid Company, Stanford, Connecticut. These materials are generally described in U.S. Patent No. 3,556,932 to Coscia et al. of January 19, 1971 and No. 3,556,933 to Williams et al. of January 19, 1971, both of which are incorporated herein by reference.

Other water-soluble resins useful in the present invention include acrylic emulsions and anionic styrene-butadiene latexes. Numerous examples of these types of resins are disclosed in U.S. Pat. No. 3,844,880 to Meisela Jr. et al. et al., issued Oct. 29, 1974, which is incorporated herein by reference.

Yet other water-soluble cationic resins found to be useful in the present invention are urea formaldehyde resins and melamine-formaldehyde resins. These polyfunctional reactive polymers have molecular weights of the order of several thousand. More common functional groups include nitrogen-containing groups such as amino groups and methylol groups attached to a nitrogen atom. rt

Polyethyleneimine type resins find use in the present invention, although they are less preferred.

More complete descriptions of the above water-soluble resins, including their manufacture, can be found in TAPPI Monograph Series No. 29 Wet Strength in Paper and Paperboard, Technical Associate or Paper ^- Industry (- New ^- York (1965), which is incorporated herein by reference. The term permanent wet strength resin means a resin that allows the paper sheet, when immersed in an aqueous environment, to retain most of its original wet strength for more than at least two minutes.

The above wet strength additives typically result in stable wet strength paper products, i.e. paper, when placed in an aqueous environment, retains a substantial portion of its original wet strength for a period of time. However, stable wet strength ⁷ may be unnecessary and undesirable in some types of paper products. Paper products, such as toilet papers, etc., are usually discarded in septic systems and the like after a short period of use. If the paper product stably retains its strength and is resistant to hydrolysis, this may lead to clogging of these systems. Recently, manufacturers have begun to add temporarily wet strength additives to paper products, so that wet strength is sufficient for the intended use, but destroys when soaked with water. The disposal of wet strength facilitates the flow of paper products through the septic systems.

Examples of suitable temporary wet strength resins include modified starch wet strength starches such as National Starch 78-0080, marketed by National Starch and Chemical Corporation (New York, N.Y.). This type of wet strength agent can be prepared by reacting dimethoxyethyl N-methyl chloroacetamide with cationic starch polymers. Modified temporary wet strength starch clarifiers are also described in U.S. Patent No. 4,675,394 to Solarek et al., Issued June 23, 1987 and incorporated herein by reference. Preferred temporary wet strength resins include those described in U.S. Patent No. 4,981,557, Bjorkquist, issued January 1, 1991, which is incorporated herein by reference.

With respect to the classes and specific examples of the above resins, both permanent and temporary wet strength, it should be understood that the resins in the list are only examples and not limitations on the scope of the invention.

Mixtures of compatible wet strength resins may also be used in the practice of the present invention.

The above lists of possible chemical additives are intended as examples only. They are not intended to limit the scope of the invention.

The following examples illustrate the practice of the invention but are not intended to limit it.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The purpose of this example is to illustrate a process that can be used to produce a substantially anhydrous self-emulsifiable chemical softening composition comprising a mixture of di (hydrogenated) tallow dimethyl ammonium methyl sulfate (DHTDMAMS) and polyoxyethylene glycol 400 (PEG-400).

Anhydrous self-emulsifiable chemical softener composition is prepared according to the following procedure: 1. separately weigh the equivalent weight of DHTDMAMS and PEG-400, 2. PEG is heated to 60 ° C, 3. DHTDMAMS is dissolved in PEG to form a molten solution at 66 ° C, 4. forming a homogeneous mixture of DHTDMAMS in PEG by appropriate stirring; and 5. cooling this homogeneous mixture to room temperature to form a solid.

The substantially anhydrous self-emulsifiable chemical softener composition of item 5 may be premixed (steps 1 to 5 above) at a chemical supplier (e.g., Sherex company, Dublin, Ohio) and then economically shipped to end users of the chemical softener composition where concentrate to the desired concentration.

Example 2

The purpose of this example is to illustrate a method that can be used to produce a substantially anhydrous self-emulsifiable chemical softening composition comprising a mixture of di (hydrogenated) tallow dimethyl ammonium methyl sulfate (DHTDMAMS) and a mixture of glycerol with PEG-400.

A substantially anhydrous self-emulsifiable chemical softener composition is prepared according to the following procedure: 1. prepare a mixture of glycerol with PEG-400 in a weight ratio of 75:25; 2. separately weigh the equivalent weight of DHTDMAMS and the mixture of items 1, 3. 4. DHTDMAMS is dissolved in the mixture of item 3 to form a molten solution at 66 ° C, 5. forming a homogeneous mixture of DHTDMAMS in the mixture of items 3 and 6 with appropriate stirring. Cool to room temperature to give a solid.

The substantially anhydrous self-emulsifiable chemical softener composition of item 6 can be premixed (steps 1-6 above) at a chemical supplier (e.g., Sherex company, Dublin, Ohio) and then economically shipped to the end users of the chemical softener composition, where it is then diluted on demand

Get concentration.

vii · ítA /.

Example 3 The purpose of this example is to illustrate a method of using blow molding

E * during drying in the manufacture of paper to produce soft and absorbent paper towel sheets which are treated with a substantially anhydrous self-emulsifiable chemical softening composition comprising a preformed mixture of di (hydrogenated) tallow dimethyl ammonium methyl sulfate (DHTDMAMS), polyoxyethylene glycol 400 (PEG-400) in the solid state and the resin is a permanent wet strength.

For a practical embodiment of the present invention, a longitudinal sieve pilot machine is used. First, a substantially anhydrous self-emulsifiable chemical softener composition is prepared by the procedure of Example 1, wherein a homogeneous preformed mixture of DHDTMAMS and PEG-400 in the solid state is dispersed in a conditioned water tank (temperature 66 ° C) to form a dispersion of podmicron vesicles. The particle size of the pouch dispersion is determined by optical microscopy. The particles have a particle size of 0.1 to 1.0 μπι. Figure 3 illustrates a cryotransmission photomicrograph at a 63,000x magnification of the DHTDMAMS vesicle dispersion with PEG-400 in a 1: 1 weight ratio. Figure 3 shows that ^_ the particles have membranes one or two thick bilayers, whose geometry ranges from closed / open vesicles, to disc-like structures and sheets.

Second, a 3% (w / w) aqueous suspension of NSK is prepared in a conventional pulper pulper. The NSK suspension is slightly cleaned and a 2% (w / w) wet strength resin solution (ie, Kymene ^(R> 557H supplied by Hercules Incorporated, Wilmington, De.)) Is added to the NSK supply line at a rate of 1% w / w. adsorption of Kymene (R) 557H to NSK is increased by an in-line mixer A 1% (w / w) carboxymethylcellulose (CMC) solution is added after the in-line mixer at a rate of 0.2% w / w to increase the fiber strength The adsorption of CMC to NSK is increased by an in-line mixer, then a 1% (w / w) chemical softening solution (DHTDMAMS / PEG) solution is added to the NSK slurry at a rate of 0.1% by weight on the dry fiber weight. The NSK suspension can be diluted to 0.2% by weight with a fan pump.

Third, a 3% by weight aqueous suspension of CTMP is prepared in a conventional pulper pulper. A non-ionic surfactant (Pegosperse) is added to the shredder at a rate of 0.2% by weight. to the dry fiber weight. To the CTMP stock pipe before the stock pump is added 1% (wt.) Solution of mixture A chemi-OF AN-plasticizer ^"_ and quick" sharply ^_ 07 l ^{-% -} hfflOtrmTa ^_ weight of the dry fibers. The adsorption of the chemical softener mixture to the CTMP can be increased by an in-line mixer. The CTMP suspension is diluted to 0.2 wt. fan pump. The pre-treated coating composition (NSK / CTMP) is mixed in a headbox and deposited on a longitudinal screen of a paper machine. This creates a base band. Dewatering is performed on the longitudinal screen of the paper machine by means of a dewatering bar and vacuum chambers. The longitudinal screen is a 5-piece woven satin configuration with 84 machine direction monofilaments and 76 cm cross-machine monofilaments per 2.54 cm. Basic wet belt

N) · ~ σ

-> what σ

α c <x n <

The CD is transferred, the pFI content is 22% by weight of the longitudinal screen of the paper machine. at the transfer site, to a photopolymer fabric with 37 linear Idaho cells and 1 cm ² , with 34% joint area and a photopolymer depth of 0.37 mm. The name Linear Idaho is based on the fact that the reinforced section of the conduit from which this assembly is originally shaped resembles a potato. However, the guide walls on the four sides are usually formed by straight lines, so this assembly is referred to as a linear Idaho rather than simply an Idaho assembly. Further dewatering is performed by vacuum drying until the web has a fiber content of 28 wt%. The patterned web is further dried by blowing air to a fiber content of 65 wt. The web is then adhered to the surface of a Yankee drying drum with a sprayed creping adhesive containing 0.25% (w / w) aqueous polyvinyl alcohol (PVA) solution. The fiber content is increased to the expected 96% before the web is dry creped with a scraper blade. The scraper blade has an oblique angle of 25 degrees and is positioned relative to the Yankee drying drum so that the access angle is 81 degrees. The Yankee Dryer Drum operates at 244 meters per minute. The dried web is wound on a roll at a speed of 214 meters per minute.

Two layers of the strip by rolling and laminating with a PVA adhesive will form paper towel products. The paper towel 2 has a basis weight of 0.1269 kg / m &lt; 2 &gt; % substantially anhydrous self-emulsifiable chemical softening composition and 1.0 wt. permanent wet strength resin. The resulting paper towel is soft, absorbent and very wet.

Example 4

The purpose of this example is to illustrate a method of using blowing during drying and in the manufacture of laminated paper by producing a soft and absorbent toilet tissue that is treated with a substantially anhydrous self-emulsifiable chemical softener composition containing a preformed mixture of di (hydrogenated) tallow dimethyl ammonium methylsulfate (DHTDMAMS). ), liquid polyoxyethylene glycol 400 (PEG-400), and temporary wet strength resins.

For a practical embodiment of the present invention, a longitudinal sieve pilot machine is used. First, a substantially anhydrous self-emulsifiable chemical softening composition is prepared by the process of Example 1, wherein the homogeneous preformed mixture of DHDTMAMS and solid state polyhydroxy compounds is melted at 66 ° C. The molten mixture is then dispersed in a conditioned water tank (temperature 66 ° C) to form a dispersion of podmicron vesicles. The particle size of the pouch dispersion is determined by optical microscopy. The particles have a particle size of 0.1 to 1.0 μη. Figure 4 illustrates a cryotransmission photomicrograph at a 63,000x magnification of the DHTDMAMS vesicle dispersion of polyhydroxy compounds in a 1: 1 weight ratio. Figure 4 shows that the particles have membranes of one or two bilayers whose geometry ranges from closed / open vesicles to disk-like and sheet-like structures.

Second, a 3% (w / w) aqueous suspension of NSK is prepared in a conventional pulper pulper. The NSK suspension is slightly cleaned and a 2% (w / w) temporary wet strength resin solution (i.e., National starch 78-0080 supplied by National Starch and Chemical Corporation, New York, NY) is added to the NSK supply line at a rate of 0, 75 wt. to the dry fiber weight. Adsorption of temporary wet strength resin to NSK fibers is increased by an in-line mixer. The NSK suspension is diluted to 0.2 wt. Third, a 3% (w / w) aqueous suspension of eucalyptus fibers is prepared in a conventional spinner. A 1% (w / w) chemical softener solution solution at a rate of 0.2% w / w is added to the eucalyptus feed line prior to the feed pump. to the dry fiber weight. The adsorption of a substantially anhydrous self-emulsifying chemical softening composition to eucalyptus fibers can be enhanced by an in-line mixer. The eucalyptus suspension is diluted to 0.2 wt. fan pump.

Processed coating composition (30 wt% NSK / 70 wt% eu32)

< -ϋ Γ— IT Cl ·? WHAT Ξ o - ( - <; & —T * WHAT O σ

<—X

in.

of the calypt) is mixed in a headbox and deposited on a longitudinal screen of a paper machine. This creates a base band. Dewatering is performed on the longitudinal screen of the paper machine by means of a dewatering bar and vacuum chambers. The longitudinal sieve is a 5-piece woven satin configuration with 84 monofilaments in the machine direction and 76 monofilaments across the machine at 2.54 cm. The base wet web is transferred from the longitudinal screen of the paper machine at a fiber content of 15% by weight. at the transfer site, to a photopolymer fabric with 87 linear Idaho cells and 1 cm ² , with 40% joint area and a photopolymer depth of 0.23 mm. Further dewatering is performed by vacuum drying until the web has a fiber content of 28 wt%. The patterned web is further dried by blowing air to a fiber content of 65 wt. The web is then adhered to the surface of a Yankee spray crepe dryer with an adhesive agent containing 0.25% (w / w) aqueous polyvinyl alcohol (PVA) solution. The fiber content is increased to the expected 96% before the web is dry creped with a scraper blade. The scraper blade has an oblique angle of 25 degrees and is positioned relative to the Yankee dryer drum so that the access angle is 81 degrees. The Yankee Dryer Drum operates at 244 meters per minute. The dried web is wound on a roll at a speed of 214 meters per minute.

,AND

The web forms a monolayer tissue product. The tissue paper has a basis weight of 0.8789 kg / m, containing 0.1 wt. % of the chemical softening composition and 0.2 wt. temporary wet strength resin. The resulting tissue paper is soft, absorbent and suitable for use as facial and / or toilet tissue paper.

Example 5

The purpose of this example is to illustrate how to use blow molding during the manufacture of laminated paper to produce a soft and absorbent toilet tissue that is treated with a substantially anhydrous self-emulsifiable chemical softener composition containing a preformed mixture of di (hydrogenated) tallow dimethyl ammonium methyl chloride (DHTDMAC). , a mixture of a po33 lyhydroxy compound (glycerol / PEG-400) in the liquid state and a dry strength resin additive .--------------- - .......... .. .............

For a practical embodiment of the present invention, a longitudinal sieve pilot machine is used. First, a substantially anhydrous self-emulsifiable chemical softener composition is prepared by the process of Example 2, wherein the homogeneous premixed DHDTMAC and solid state polyhydroxy compounds are melted at 66 ° C. The molten mixture is then dispersed in a conditioned water tank (temperature 66 ° C) to form a dispersion of podmicron vesicles. The particle size of the pouch dispersion is determined by optical microscopy. The particles have a particle size of 0.1 to 1.0 μια.

Figure 5 illustrates a cryotransmission photomicrograph at a 63,000x magnification of the DHTDMAC vesicle dispersion of polyhydroxy compounds in a 1: 1 weight ratio. Figure 5 shows that the particles have membranes of one or two bilayers, whose geometries range from closed / open vesicles to disk-like and sheet-like structures.

Second, a 3% (w / w) aqueous suspension of NSK is prepared in a conventional pulper pulper. The NSK suspension is slightly cleaned and a 2% dry strength resin solution (i.e., Acco 514, Acco 711 supplied by American Cyanamid Company, Fairfield, OH) is added to the NSK supply line at a rate of 0.2% by weight. . to the dry fiber weight. The adsorption of the dry strength resin to the NSK fibers is increased by an in-line mixer. The NSK suspension is diluted to 0.2 wt. Thirdly, - ~ v ^_ k'onvenčním ^- rozvTákňOvači "výmětir" was ^- prepared 3% (hmotrrr) reserve the aqueous slurry of Eucalyptus fibers. A 1% (w / w) chemical softener solution solution is added to the eucalyptus feed line before the supply pump at a rate of 0.2%. to the dry fiber weight. The adsorption of the substantially anhydrous self-emulsifying chemical softening composition to eucalyptus fibers can be increased by an in-line mixer. The eucalyptus suspension is diluted to 0.2 wt. fan pump.

Treated coating composition (30 wt% NSK / 70 wt% eu34)

of the calypt) is mixed in a headbox and deposited on a longitudinal screen of a paper machine. This creates a base band. Dewatering is performed on the longitudinal screen of the paper machine by means of a dewatering bar and vacuum chambers. The longitudinal screen is a 5-piece woven satin configuration with 84 monofilaments in the machine direction and 76 monofilaments across the machine at 2.54 cm. The base wet web is transferred from the longitudinal screen of the paper machine at a fiber content of 15% by weight. at the transfer site, to a photopolymer fabric with 87 linear Idaho cells and 1 cm ² , with 40% joint area and a photopolymer depth of 0.23 mm. Further dewatering is performed by vacuum drying until the web has a fiber content of 28 wt%. The patterned web is further dried by blowing air to a fiber content of 65 wt. The web is then adhered to the surface of a Yankee spray drying creping adhesive containing 0.25% (w / w) aqueous polyvinyl alcohol (PVA) solution. The fiber content is increased to the expected 96% before the web is dry creped with a scraper blade. The scraper blade has an oblique angle of 25 degrees and is positioned relative to the Yankee drying drum so that the access angle is 81 degrees. The Yankee Dryer Drum operates at 244 meters per minute. The dried web is wound on a roll at a speed of 214 meters per minute.

Tissue paper products are made from two belt layers and laminated by the layer bonding process. The tissue paper has 2 basis weight of 0.1123 kg / m &lt; 2 &gt; % substantially anhydrous self-emulsifiable chemical softening agent and 0.1 wt. dry strength resins. The resulting tissue paper is soft, absorbent and suitable for use as facial and / or toilet tissue paper.

Example 6

The purpose of this example is to illustrate a method of using conventional drying in the manufacture of soft and absorbent toilet tissue which is treated with a substantially anhydrous self-emulsifiable chemical softener composition containing a preformed mixture of di (hydrogenated) tallow dimethyl ammonium 35-methylsulfate (DHTDMAMS) 400 polyoxyethylene glycols 400 (PEG) in the solid state and dry strength resin additives.

For a practical embodiment of the present invention, a longitudinal sieve pilot machine is used. First, a substantially anhydrous self-emulsifiable chemical softener composition is prepared by the procedure of Example 1, wherein a homogeneous preformed mixture of DHDTMAMS and PEG-400 in the solid state is dispersed in a conditioned water tank (temperature 66 ° C) to form a dispersion of podmicron vesicles. The particle size of the pouch dispersion is determined by optical microscopy. The particles have a particle size of 0.1 to 1.0 μιη. Figure 3 illustrates a cryotransmission photomicrograph at a 63,000x magnification of the DHTDMAMS vesicle dispersion with PEG-400 in a 1: 1 weight ratio. Figure 3 shows that the particles had membranes of one or two bilayers, whose geometries range from closed / open vesicles to disk-like and sheet-like structures.

Second, a 3% (w / w) aqueous suspension of NSK is prepared in a conventional pulper pulper. The NSK suspension is slightly cleaned and a 2% dry strength resin solution (i.e., Acco 514, Acco 711 supplied by the American Cyanamid Company, Wayne, N.J.) is added to the NSK supply line at a rate of 0.2% by weight. to the dry fiber weight. The adsorption of the dry strength resin to the NSK fibers is increased by an in-line mixer. The NSK suspension is diluted to 0.2 wt. Third, a 3% (w / w) aqueous suspension of eucalyptus fibers is prepared in a conventional pulper. A 1% (w / w) chemical softener solution solution is added to the eucalyptus feed line before the feed pump at a rate of 0.2% w / w. to the dry fiber weight. The adsorption of the chemical softening composition to eucalyptus fibers can be increased by an in-line mixer. The eucalyptus suspension is diluted to 0.2 wt. fan pump.

The treated coating composition (30 wt% NSK / 70 wt% eucalyptus) is mixed in the headbox and deposited on the longitudinal screen of the paper machine. This creates a base band. To poΙΌ · x-χ ·

CC-O <

“0 - < r ~ 70 X) < > O r— ' GO 3 <3 • -and - < zr. Ys O CL b < < CL

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C, X paper machine screen. This creates a base band. Dewatering is performed on the longitudinal screen of the paper machine by means of a dewatering bar and vacuum chambers. The longitudinal screen is a 5-piece woven satin configuration with 84 machine direction monofilaments and 76 cm cross-machine monofilaments per 2.54 cm. The base wet web is transferred from the longitudinal screen of the paper machine at a fiber content of 15% by weight. at the point of transmission, to a conventional belt. Further dewatering is performed by vacuum drying until the web has a fiber content of 35 wt%. The web is further adhered to the surface of a Yankee drying drum. The fiber content is increased to the expected 96% before the web is dry creped with a scraper blade. The scraper blade has an oblique angle of 25 degrees and is positioned relative to the Yankee drying drum so that the access angle is 81 degrees. The Yankee drying drum operates at a speed of 244 meters per minute. The dried web is wound on a roll at a speed of 214 meters per minute.

Tissue paper products are produced from the two layers of the web and laminated by the layer bonding process. The tissue paper has a weight of 0.1123 kg / in2 and contains 0.1 wt. % of a mixture of a substantially anhydrous self-emulsifiable chemical softening agent and 0.1 wt. dry strength resins. The resulting tissue paper is soft, absorbent and suitable for use as facial and / or toilet tissue paper.

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Claims (10)

Patents Claims cn§oa 1. A substantially anhydrous self-emulsifiable chemical softening composition, characterized in that it comprises a mixture of: (a) quaternary ammonium compounds of the general formula I R, R ₂ - N ⁺ - R Χ '(I) AND R x wherein each R ₂ is C 1 -C 6 alkyl, C 1 -C 6 hydroxyalkyl or a mixture thereof, preferably C 1 -C 3 alkyl, most preferably methyl, each R _R is hydrocarbyl a C 14 -C 22 group or a mixture thereof, preferably an C 16 -C 18 alkyl group, and X 'is a suitable anion, preferably chloride or methyl sulfate, and b) a polyhydroxy compound selected from the group consisting of glycerol, polyglycerols having a weight average molecular weight of 150 to 800 and polyoxyethylene glycols and polyoxypropylene glycols with a weight average molecular weight of 200 to 4000, preferably 200 to 1000, most preferably 200 to 600, wherein the weight ratio of the quaternary ammonium compound to the polyhydroxy compound ranges from 1: 0.1 to 0.1: 1, preferably from 1: 0.3 to 3: 1, and most preferably from 1: 0.7 to 0, 7: 1, the polyhydroxy compound is admixed with the quaternary ammonium compound at a temperature at which the polyhydroxy compound is miscible with the quaternary ammonium compound and the moisture content of the chemical softening composition is less than 20% by weight. The substantially anhydrous self-emulsifiable chemical softener composition of claim 1, wherein the chemical softener composition is a stable, homogeneous solid or viscous liquid at a temperature greater than 20 ° C. A substantially anhydrous self-emulsifiable chemical softening composition according to claim 1 or 2, wherein di (hydrogenated) tallow dimethyl ammonium chloride or di (hydrogenated) tallow dimethyl ammonium methyl sulfate is used as the quaternary ammonium compound. A substantially anhydrous self-emulsifying chemical softening composition according to any one of claims 1 to 3, characterized in that the quaternary ammonium compound is mixed with the polyhydroxy compound at a temperature of at least 40 ° C, preferably 56 to 68 ° C. A substantially anhydrous self-emulsifiable chemical softener composition according to any one of claims 1 to 4, wherein the quaternary ammonium compound is in a liquid crystal state or in a liquid state when mixed with a polyhydroxy compound. An aqueous dispersion comprising a substantially anhydrous self-emulsifiable chemical softening composition according to any one of claims 1 to 5 and an aqueous medium, wherein a homogeneous mixture of the quaternary ammonium compound and the polyhydroxy compounds is self-dispersed in the aqueous medium to form a dispersion of submicron vesicles. Aqueous dispersion according to claim 6, characterized in that the temperature of the aqueous medium is at least 20 ° C. Aqueous dispersion according to claim 6 or 7, characterized in that the homogeneous mixture of the quaternary ammonium compound and the polyhydroxy compound is in the solid state prior to dispersion in the aqueous medium. Aqueous dispersion according to claim 6 or 7, characterized in that the homogeneous mixture of quaternary ammonium 10. The compound and polyhydroxy compound are in a liquid state prior to dispersion in this aqueous medium. A substantially anhydrous self-emulsifiable chemical softening composition according to any one of claims 1 to 5, wherein the moisture content of the chemical softening agent is less than 10% by weight. From here: (Fahrenheit scale) 50 100 150 200 250 300