HUT74116A - Waterless self-emulsifiable chemical softening composition useful in fibrous cellulosic materials - Google Patents

Description

FIELD OF THE INVENTION The present invention relates to substantially anhydrous self-emulsifying chemical softeners, more particularly to anhydrous self-emulsifying chemical softening compositions useful for treating fibrous cellulosic materials such as silk crepe paper webs. The silk crepe paper bands so treated can be used to make soft absorbent paper products such as towels, napkins, face towels and toilet paper.

Paper tapes or braids, sometimes referred to as silk / tissue / or webs, are widely used in modern society. These items, such as paper towels, napkins, face wipes and toilet paper, are regular articles of commerce. It has long been recognized that three important physical properties of these products are softness, suction capacity, in particular suction capacity for aqueous systems, and strength, especially wet strength. Research and development attempts are made to improve all of these properties without adversely affecting the others, and to improve two or three properties at the same time.

Softness is the sensation of the sensation perceived by the consumer when a man or woman wears a special product, wipes his skin or crumples in his hand. This sense of touch is a combination of several physical attributes. One of the most important properties related to softness is the rigidity of the paper from which the product is made. On the other hand, stiffness is generally believed to be directly related to the dry tensile strength of the paper and the stiffness of the fibers from which the paper is made.

The strength of the products and webbing they are made of is its ability to retain its physical integrity and withstand tear, tear and tear under conditions of use, especially when wet.

The absorbency of the products and webs they are made of is a measure of the amount of liquid they can absorb, especially aqueous solutions and dispersions. The overall absorbency, as perceived by the consumer, is generally a combination of the total amount of liquid absorbed by a particular mass of crepe paper to saturation and the rate at which this mass absorbs the liquid.

It is widely known to use wet strength resins to enhance the strength of the paper web. For example, Westfelt has described many of these substances and described their chemistry in Cellulose Chemistry and Technology, 13, 813-825 / 1979 / 7.7. It is mentioned in U.S. Patent No. 3,755,220 that certain chemical additives which are laxatives / known as debonding agents /, they act on the natural fiber-to-fiber bonds that are formed during sheeting in the papermaking process. This reduction in joints results in a softer or less coarse, paper-like finish. The above patent describes the use of wet strength resins combined with the use of loosening agents to eliminate undesirable properties of loosening agents. Loosening agents reduce both dry and wet tensile strength.

U.S. Patent No. 3,821,068 also discloses that chemical release agents can be used to reduce stiffness and enhance the softness of silk crepe paper webs.

Chemical release agents are mentioned in numerous publications, such as U.S. Patent 3,554,862. These materials are quaternary ammonium salts such as coconut alkyl trimethyl ammonium chloride, oleyl trimethyl ammonium chloride, di / hydrogenated / tallowalkyl ammonium chloride and stearyl trimethyl ammonium chloride.

U.S. Patent No. 4,144,122 discloses the use of complex quaternary ammonium compounds such as bis (alkoxy) - 2 - hydroxy - propylene - quaternary ammonium chlorides to soften paper webs. The authors also attempt to overcome the loss of absorbency caused by the use of laxatives by using ethylene oxide and propylene oxide adducts of nonionic surfactants such as aliphatic alcohols.

Armak Company, of Chicago, Illinois.

in its Bulletin 76-17 / year dimethyldi (hydrogenated) ^-

describes the use of tallowalkylammonium chloride in combination with fatty acid esters of polyoxyethylene glycols which give the silk crepe paper webs softness and absorbency.

For example, U.S. Patent No. 3,301,746 discloses the results of research into improved paper webs. Despite the high quality of the webs produced by the process described herein, and despite the commercial success of the products made from these webs, attempts have been made to produce improved products.

For example, U.S. Patent No. 4,158,594 teaches a process that is claimed to form strong, soft, fibrous germs. Specifically, it is reported that the silk crepe paper web, which can be softened by the addition of chemical release agents, can be strengthened by gluing one surface of the web to a creping surface during manufacture, with a binder / g of acrylic latex. water-soluble resin or elastomeric binder / which is glued to one side of the web and to the creping surface in a fine-print arrangement, and the web is creped from the creping surface to form a paper web.

Conventional quaternary ammonium compounds such as the well-known dialkyldimethylammonium salts such as difaggyalalkyldimethylammonium chloride, difaggyalalkyldimethyl

-ammonium methyl sulfate, di / hydrogenated / tallow alkyl dimethyl ammonium chloride, etc. / effective chemical release agents. Unfortunately, these quaternary ammonium compounds are not hydrophilic. Applicants have found that the chemical softening compositions of the present invention increase both the softness and the rate of absorption of fibrous cellulosic materials.

The production of chemical softeners containing these plasticizers in substantially anhydrous forms further reduces the cost of transporting the product (due to its lower weight), the cost of its packaging material and the cost of mechanical equipment required to process the chemical softeners / less equipment for processing aqueous dispersions. The present invention also provides safety benefits to the environment by eliminating organic solvents, in particular volatile organic solvents, commonly used in the preparation of concentrated plasticizers.

One object of the present invention is to provide a substantially anhydrous, self-emulsifying chemical plasticizer for treating fibrous cellulosic materials.

Another object of the present invention is to provide soft, absorbent silk crepe paper products.

It is a further object of the present invention to provide a process for producing soft, absorbent silk crepe paper products.

The above and other objects are achieved by the use of the invention as will be apparent from the following description.

- 7 becomes.

The present invention relates to a substantially anhydrous, self-emulsifying chemical softening composition useful for treating fibrous cellulosic materials. Briefly, the anhydrous self-emulsifying chemical softener composition is a mixture of the following components: a quaternary ammonium compound of formula (I) wherein each R 1 substituent is C 1 -C 6 alkyl or hydroxyalkyl or a mixture thereof; each R 1 substituent is a C 14 -C 22 hydrocarbon group or a mixture thereof; and megfelelő ^{Θ is} a suitable anion; and b) a polyhydroxy compound such as glycerol, polyglycerol having a weight average molecular weight of about 150 to about 800, or polyoxyethylene glycol or polyoxypropylene glycol having a weight average molecular weight of about 200 to about 4000;

the weight ratio of the quaternary ammonium compound to the polyhydroxy compound in the mixture is about 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 softener composition of the present invention is a stable, homogeneous, solid, or viscous liquid at temperatures of about 20 ° C or higher. The liquid has a liquid or liquid crystalline phase structure. The substantially self-emulsifying chemical softener composition has a moisture content of less than about 20% by weight, the chemical softener composition has a moisture content of less than about 10% by weight, and the chemical softener composition preferably has a moisture content of less than about 5% by weight.

Suitable quaternary ammonium compounds for use in the present invention include well-known dialkyldimethylammonium salts such as difaggyualkyldimethylammonium chloride (DTDMAC), difaggyualkyldimethylammonium methylsulphate (DTDMAMS), di / hydrogenated dimethylammonium ammonium methyl sulfate (DHTDMAMS) and di (hydrogenated) tallow alkyl dimethyl ammonium chloride (DHTDMAC).

Polyhydroxy compounds useful in the present invention include glycerol, polyglycerols having a weight average molecular weight of about 150 to about 800 or polyoxyethylene glycols having a weight average molecular weight of about 200 to about 4000, preferably polyoxyethylene glycols having a weight average molecular weight of about 200 to about 600.

Briefly, the process for producing the webs of silk crepe paper according to the invention involves forming the papermaking pulp from said components, layering the papermaking pulp on a perforated surface such as a Fourdrinier sieve, and removing water from the layered pulp.

Unless otherwise stated, all percentages, ratios, and proportions are by weight unless otherwise stated.

While the invention is described in detail by the appended claims and is clearly claimed by the present invention,

however, it is believed that the invention will be more fully understood from the following description when the accompanying drawings are included.

Figure 1 illustrates phase diagrams of dioctadecyldimethylammonium methyl sulfate (DODMAMS) and DHTDMAMS.

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

Figure 3 is a cryo-transmission micrograph of a 2% dispersion of a 1: 1 weight ratio of a solid premix of DHTDMAMS and PEG-400 system (X 63,000).

Figure 4 is a cryo-transmission micrograph of a 2% dispersion of a 1: 1 tc ratio DHTDMAMS and PEG-400 system liquid premix (X 63,000).

Fig. 5 is a cryo-transmission micrograph of a 2% dispersion of a 1: 1 t / v DHTDMAC dilution and a liquid premix of glycerol and PEG-400 system (X 63,000).

The present invention will be described in detail below.

While the invention is described in more detail by the appended claims and is a clear claim on the subject matter of the invention, it is believed that the invention will be more fully understood from the following detailed description and examples.

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

The term homogeneous mixture as used herein refers to compositions in which the quaternary ammonium compound and the polyhydroxy compound are dissolved in each other.

- 10 or dispersed.

As used herein, the term "self-emulsifying" refers to compositions which, when added to a liquid carrier such as water, form a uniform colloidal dispersion with the aid of minimal shear, warming, dispersing.

As used herein, the term "crepe paper web", "web", "ribbon", "papiriv" and "paper product" refers to papermaking webs which are prepared by making aqueous papermaking pulp by layering the pulp on a perforated surface such as Fourdrinier sieve and fibrous pulp. with or without water extraction, with or without pressure, and by evaporation.

The aqueous papermaking pulp used herein is an aqueous suspension of papermaking fibers and the chemicals described above.

The first step in the process of the present invention is the production of an aqueous pulp for papermaking. The pulp contains papermaking fibers (sometimes referred to as wood pulp) and a mixture of at least one quaternary ammonium compound and at least one polyhydroxy compound, as described below.

It will be appreciated that all variants of wood pulp generally contain the papermaking fibers used in the process of the present invention. However, other cellulosic fibrous materials such as cotton, luggage, rayon and the like can be used, and are not excluded from the invention. The wood pulps that can be used in the present case are kraft, sulphite and sulphate pulps, and wood pulps such as wood chips, thermomechanical celluloses and chemically modified thermomechanical celluloses (CTMP). Celluloses from both deciduous and coniferous trees can be used. Fibers derived from recycled paper, which may include any or all of the above categories, as well as other non-fibrous materials, such as fillers and binders, used to facilitate the production of the original paper may also be used in the present process. The papermaking fibers used in the process of the present invention preferably consist of kraft pulp from northern softwoods.

Anhydrous, self-emulsifying chemical plasticizers

The chemical softening compositions of the present invention comprise as an essential component a mixture of a quaternary ammonium compound and a polyhydroxy compound. The ratio of the quaternary ammonium compound to the polyhydroxy compound is about 1: 0.1 to 0.1: 1, the weight ratio of the quaternary ammonium compound to the polyhydroxy compound is preferably about 1: 0.3 to 0.3: 1, the quaternary ammonium compound and more preferably the weight ratio of the polyhydroxy compound is from about 1: 0.7 to 0.7: 1, although the ratio will vary depending on the molecular weight of the particular polyhydroxy compound and / or quaternary ammonium compound used.

Compounds of the above types are further described below.

• · · · · · · · · · · · · · · · · · ·

A. Quaternary ammonium compounds

The substantially water-free, self-emulsifiable chemical softening compositions comprising a quaternary one / 1 / Formula ammonium compound as an essential component, wherein each is from 14 to 22 carbon atoms in the hydrocarbon group, preferably tallow, _R2 is a C1-6 alkyl or hydroxyalkyl, preferably <S>

C 1-3 alkyl and X is a suitable anion such as a halide (e.g. chloride or bromide) or methylsulfate. As described by Swern / Ed. in Baily's Industrial Oil and Wood Products, Third Edition, John Wiley and Sons / New York 1964 / J is a naturally occurring, variable composition. Table 6.13 of the above publication illustrates that 78% or more of the fatty acids generally contain 16 or 18 carbon atoms. Half of the fatty acids present in tallow are generally unsaturated, mainly in the form of oleic acid. Both synthetic and natural tallow fall within the scope of the invention. Preferably, each R 16 is C 16 -C 18 alkyl, most preferably each R 16 is straight-chain C 18 alkyl; R _{2 is} preferably methyl; and chloride or methyl sulfate ion.

Examples of quaternary ammonium compounds useful in the present invention include well-known dialkyldimethylammonium salts such as difaggyalalkyldimethylammonium chloride, difaggyalkyldimethylammonium methyl sulfate, di / hydrogenated / tallowalkyldimethylammonium chloride, di / hydrogenated / tallow dimethyl ammonium methyl sulfate. This specialty material is commercially available from Sherex Chemical Company Inc. of Dublin, Ohio under the trade name of Varisoft 137.

B. Polyhydroxy Compounds

The chemical softener composition also contains a polyhydroxy compound as an essential component.

The polyhydroxy compounds useful in the present invention are glycerol, polyglycerols having a weight average molecular weight of about 150 to about 800, and polyoxyethylene glycols and polyoxypropylene glycols having a weight average molecular weight of from about 200 to about 4000, preferably from about 200 to about 1000, most preferably from about 200 to about 1000. 600. Polyoxyethylene glycols having a weight average of about 200 to about 600 are particularly preferred. Mixtures of the polyhydroxy compounds described above can also be used. For example, mixtures of glycerol and polyoxyethylene glycols having a weight average molecular weight of from about 200 to about 1000, more preferably from about 200 to about 600, may be used in the process of the invention. The weight ratio of glycerol to polyoxyethylene is preferably from about 10: 1 to 1:10.

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

The above-described anhydrous, self-emulsifying chemical plasticizer composition, i.e., a mixture of a quaternary ammonium compound and a polyhydroxy compound, preferably diluted to the desired concentration, is used to form a dispersion of the quaternary ammonium compound and the polyhydroxy compound in a papermaking machine. , at a convenient point before the Fourdrinier sieve or the sheet forming section. However, the use of the chemical softener composition described above, after forming a wet paper web and even before the web is completely compressed, provides significant benefits in terms of softness, absorbency, and wet strength, and is also specifically included in the invention.

It has been found that the chemical softener composition is more effective when the quaternary ammonium compound and the polyhydroxy compound are premixed before being added to the papermaking pulp. A preferred method, which will be described in more detail in Example 1, is to first heat the polyhydroxy compound to about 66 ° C and then add the quaternary ammonium compound to the hot polyhydroxy compound to form a homogeneous liquid. The weight ratio of the quaternary ammonium compound to the polyhydroxy compound is about 1: 0.1 to 0.1: 1; the weight ratio of the quaternary ammonium compound to the polyhydroxy compound is preferably from about 1: 0.3 to about 0.3: 1; more preferably the weight ratio of the quaternary ammonium compound to the polyhydroxy compound ·· · »··

From about 1: 0.7 to about 0.7: 1, but this ratio depends on the molecular weight of the particular polyhydroxy compound and / or quaternary ammonium compound used. The chemical softener composition has a moisture content of less than about 20% by weight, the chemical softener composition has a moisture content of less than about 10% by weight, and the chemical softener composition has a moisture content of less than 5% by weight. Importantly, the chemical softener composition is a stable, homogeneous solid or viscous liquid at temperatures of about 20 ° C or higher.

The substantially anhydrous, self-emulsifying chemical plasticizer composition may be premixed in a chemical apparatus (e.g., the Sherex Company of Dublin, Ohio). Producing chemical softeners containing these plasticizers in substantially anhydrous form reduces the cost of shipping the product (due to its lower weight), saves packaging costs and saves on machinery for chemical softener preparation / requires less equipment to process the aqueous dispersion / . In addition, the present invention is advantageous for the safety of the environment since organic solvents, especially volatile organic solvents, are not used.

The end user of the chemical softener composition will simply dilute the mixture with a liquid carrier (i.e., water) to form an aqueous dispersion of the quaternary ammonium compound / polyhydroxy compound mixture,

which is then added to the papermaking pulp. The homogeneous mixture of the quaternary ammonium compound and the polyhydroxy compound may be in solid or liquid form before being dispersed in the aqueous medium. The mixture of the quaternary ammonium compound and the polyhydroxy compound is diluted with an aqueous carrier such as water to a concentration of preferably about 0.01 to about 25% by weight of the chemical softener composition before being added to the papermaking pulp. The temperature of the liquid carrier is from about 20 ° C to about 80 ° C. After mixing, the quaternary ammonium compound and the polyhydroxy compound are present in the form of particles dispersed in the liquid carrier. The average particle size is preferably about 0.0.1. 10 microns, most preferably about 0.1 to about 1.0 microns. As shown in Figure 3-5. Figure 3B shows the dispersed particles in the form of closed vesicles or open particles.

Surprisingly, it has been found that the absorption of the polyhydroxy moiety on the paper is greatly enhanced when premixed with the quaternary ammonium compound and added to the paper by the above process. At least 20% of the mixture of polyhydroxy compound and quaternary ammonium compound is added to the fibrous cellulose, and the retention amount of the quaternary ammonium compound and polyhydroxy compound is preferably about 50 to about 90%.

It is important that absorption occurs at a concentration and for a period that is consistent with the production of paper ·· · «·«

- Practically suitable for use on 17 bars. In order to better understand the surprisingly high retention rate of the polyhydroxy compound on the paper, a solution of a di / hydrogenated / tallow alkyl alkyl dimethyl 1-ammonium methyl sulfate / DHTDMAMS / polyoxyethylene glycol-400 melt solution and aqueous dispersion was studied.

Without being bound in theory or otherwise limited to the present invention, the following description is offered to explain how the quaternary ammonium compound promotes the absorption of the polyhydroxy compound on paper.

The physical state of di / hydrogenated / tallow alkyl dimethyl ammonium methyl sulfate (DHTDMAMS, R ₂ N ⁺ / CH / ₂ CH ₂ OSO ₂ ) and DODMAMS was obtained by X-ray and MMR analysis from the commercial mixture. Dioctadecyldimethylammonium methyl sulfate / DODMAMS,? 18 ^ 37/2 ^{n +} / CH3 / 2CH3OSO3 / a is a major component of DHTDMAMS and serves as a model compound for the commercial blend. It is advisable first to review the simpler DODMAMS system and then the more complex commercial DHTDMAMS blend.

Depending on the temperature, DODMAMS exists in one of the following four phases / 1. Figure 2: two polymorphic crystals (X $ and X ⁰ **), a lamellar (Lam) liquid crystal or a liquid phase. X 4 crystals exist between room temperature and 47 ° C. At this temperature, the polymorph o

X ^ crystal, which is converted to lamellar liquid at 72 ° C ··· ♦ · · ·. . «• * * · · ··· ··· into a crystalline phase. This phase, in turn, is converted to an isotropic liquid at 150 ° C. It is expected that DHTDMAMS resembles DODMAMS in physical behavior, except that phase transition temperatures are lower and wider. For example, the transition from crystal X to crystal X occurs at 27 ° C at DHTDMAMS instead of 47 ° C, which is typical of DODMAMS. The calorimetric data also shows that more crystal 0-lamellar phase transitions occur at DHTDMAMS than at DODMAMS. These transitions have a maximum initial temperature of 56 ° C, in good agreement with the X-ray data.

Dioctadecyldimethylammonium chloride (DODMAC) exhibits a qualitatively different behavior from DODMAMS in that the crystalline liquid crystalline phase does not exist in this compound (Laughlin et al., Journal of Physical Chemistry, Physical Science of Dioctadecyldimethylammonium Water) System. 1. Equilibrium Phase Behavior, 1990, volume 94, pages 2546-2552J. However, it is believed that this difference is not significant for the use of this compound (or its commercial analogue, DHTDMAC) in the treatment of paper.

Mixtures of DHTDMAMS and PEG-400

A 1: 1 mixture by weight of these two materials was studied, and the probable model for the phase behavior of this system is illustrated in Figure 2. DODMAMS and PEG do not mix at high temperatures - as shown in the diagram - they are in two liquid phases.

· Ο ·. * Ζ · ,, · _t

- 19 present together. When the mixture of the two liquids is cooled in this region, a lamellar phase is separated from the mixture. Thus, this study shows that these two materials, which do not mix at high temperatures, mix at lower temperatures in the lamellar liquid crystalline phase. At even lower temperatures, it is expected that the crystalline phases will separate from the lamellar phase and the compounds will become immiscible again.

Thus, it follows from these studies that, in order to form a good dispersion of DHTDMAMS and PEG-400 in water, the water-diluted premix must be maintained at an intermediate temperature within which the two compounds are miscible.

Mixtures of DHTDMAC and PEG-400

Phase studies of these two materials, using the batch dilution method, show that their physical behavior is significantly different from DHTDMAMS1. There are no liquid crystalline phases here. These compounds, as liquid solutions, are miscible over a wide temperature range, indicating that these mixtures can be dispersed within the above temperature ranges. There is virtually no upper limit to mixing.

Preparation of dispersions

Dispersions of any of these materials can be prepared by diluting the premix, which is maintained at a temperature where the polyhydroxy compound and the quaternary ammonium compound are mixed, with water. It is of little importance that the compounds mix as a liquid crystalline phase (as in DHTDMAMS) or as a liquid phase (as in DHTDMAC). Neither DHTDMAMS nor DHTDMAC is water soluble, so diluting any dry phase with water results in the quaternary ammonium compound precipitating in the form of small particles. Both quaternary ammonium compounds precipitate out of dilute aqueous solutions at higher temperatures than the liquid crystalline phase, regardless of whether the dry solution was liquid or liquid crystalline. The polyhydroxy compound is soluble in water in all ratios so that it does not precipitate.

Cryo-electron microscopy shows that the particles present in the dispersion are about 0.1 to 1.0 micrometers in size and have a very variable structure. Some are sheets (curled or flat), while others are closed vesicles. The membranes of each particle are bilayer in molecular dimensions where the head groups are directed towards the water and the back portions are together. Presumably, PEG is attached to these particles. Using the dispersions prepared in this way on the paper, the result is that the quaternary ammonium ion is attached to the paper, strongly promoting the absorption of the polyhydroxy compound on the paper and providing the desired improvement in softness while retaining its wettability.

Status of dispersions

If the above-mentioned dispersions are cooled, then

- Partial crystallization of the substance may occur in colloidal particles. However, it is likely that it will take a long time (possibly months) to reach equilibrium so that the memranes in the paper interacting particles are disordered.

The vesicles containing DHTDMAMS and PEG are likely to burst when the fibrous cellulosic material is dried. Once the vesicle is broken, most of the PEG component can penetrate inside the cellulosic fibers, where it improves the flexibility of the fiber. Importantly, a portion of the PEG remains on the surface of the fiber, where it enhances the absorption rate of the cellulosic fibers. Due to ionic interactions, most of the DHTDMAMS component remains on the surface of the cellulosic fiber, where it improves the surface feel and softness of the paper product.

In the process of the present invention, the second step is to lay the papermaking pulp using an additive chemical softener composition as described above on a perforated surface, and the third step is to remove water from the pulp thus pulverized. The techniques and equipment that can be used to perform these two operations are well known to those skilled in the art of papermaking. Preferred silk crepe papers according to the invention contain from about 0.005 to about 5.0% by weight, more preferably from about 0.03 to 0.5% by weight, of the chemical softener composition described above on a dry fiber basis.

The process of the invention is applicable to silk crepe papers in general, including, but not limited to, traditional felt-pressed silk-crepe papers, high-specific volume, pattern-compacted silk-crepe papers, and high-specific, non-pressed silk-crepe papers. The crepe paper may be homogeneous or multilayer; and the products thereof may comprise one or more elementary layers. Paper structures made of laminated webs are disclosed in U.S. Patent No. 3,994,771. Wet-layered, multi-part, soft, low-density, and absorbent paper structures are generally made of two or more layers of pulp, preferably consisting of different types of fibers. Preferably, the layers are formed by placing separate streams of dilute fiber suspensions, the fibers generally being relatively long soft fibers and relatively short hard fibers used in papermaking. Laying is performed on one or more endless perforated sieves. The layers are then combined to form a laminated multi-piece tape. Subsequently, the laminated web is adhered to the surface of a web-like dryer / printer screen by exerting liquid pressure on the web, and thereafter is pre-dried thereafter as part of the low-density paper manufacturing process. The paper web may be layered according to the fiber type or the fiber content of each layer may be substantially the same. Preferably, the four, 2, 2 cubic meters of silk crepe paper have a weight of about 10 g / m 2 to about 65 g / m 2 and a density of about 0.60 g / ml or less.

Preferably, the basis weight is about 35 g / m 2 or less; and a density of about 0.30 g / ml or less. Most preferably, the density is between 0.04 and 0.20 g / ml.

Conventionally pressed silk crepe papers and methods for making such papers are known in the art. Such papers are generally prepared by layering paper pulp onto a perforated sheet forming screen. This sheet forming screen is often referred to in the art as the Fourdrinier screen. Once the pulp has been deposited on a forming screen, it is called a web. The web is dewatered by applying to a dewatering felt, the web is squeezed and dried at a higher temperature. The specific processes and typical equipment for producing paper webs by the method described herein are well known to those skilled in the art. In a typical process, low-density cellulosic pulp is prepared in a high-pressure overhead cabinet. The overhead cabinet has an opening through which a thin layer of cellulosic pulp is passed to the Fourdrinier sieve to form a wet web. Thereafter, the web is generally dewatered to about 7% to about 25% of the total web weight / fiber density by vacuum dewatering and further dewatered when pressed under pressure from opposite mechanical members, such as rollers.

The dewatered web is then pressed further as it passes and dried in a flow drum dryer, known in the art as the Yankee dryer. The Yankee dryer can be pressurized by mechanical means, thereby clamping an opposed cylindrical drum against the web. Vacuum can also be applied to the web as it is pressed onto the drying surface of the Yankee. Multiple Yankee dryers can be used to create additional pressure between the drums, if necessary. Fabricated crepe paper structures are referred to hereinafter as conventional pressed crepe paper structures. These spurs are compressed as the paper web is subjected to significant mechanical compression forces while the fibers are still wet and then dried in a compressed state.

Patterned compacted silk crepe papers are characterized by having a relatively low fiber density, high specific volume zone, and a pattern consisting of relatively high fiber density compacted zones. High specific volume zones are called pillow regions. Compressed zones are regions of knuckles. Compressed zones may be located separately in the high specific volume field or in the high specific volume field and may be partially or fully interconnected. Preferred processes for making patterned crepe paper are described in U.S. Patent Nos. 3,301,746, 3,974,025, 4,191,609 and 4,637,859.

In general, patterned compacted webs are preferably made by pulping the papermaking pulp.

perforated sheet forming screen, such as a Fourdrinier screen, to form a wet web, and then place the web alongside a patterned substrate. The web is pressed against the pattern substrate to form compacted zones within the web that locally correspond to the points of contact between the pattern substrate and the wet web. The remainder of the web, which did not compress during this operation, is the high specific volume field. This high specific volume field can be further relaxed using a hydrostatic pressure such as a vacuum type device or a flow dryer. The web is dewatered and optionally pre-dried in such a way as to substantially avoid compressing the high specific volume field. This is preferably done by means of a hydrostatic pressure, such as a vacuum type device or a blow dryer, or by mechanically pressing the paper web against a patterned carrier so as not to compress the high specific volume zone. The dewatering, possible pre-drying and compaction zones operations may be combined or partially combined, thus reducing the total number of process operations performed. After forming the compacted zones, dewatering and possibly pre-drying, the paper web is completely dried, preferably also avoiding mechanical pressing. Preferably, about 8 to about 55% of the surface of the crepe paper comprises compacted screen knots having a relative density of at least 125% of the density of the high specific volume field.

• · ···························································•

The patterned substrate is preferably a printer transfer screen with a patterned position of the screen knots, which acts as a pattern substrate to facilitate the formation of compacted zones by application of pressure. The pattern of the screen knots forms the pattern arrangement of said substrate. Printer transfer screens are described in 3 301 746,

821,068, 3,974,025, 3,573,164, 3,473,576, 4,239,065, and

U.S. Patent No. 528,239.

Preferably, the pulp is first formed into a wet paper web on a perforated forming screen, such as a Fourdrinier screen. By dehydrating the paper web and transferring it to a printer screen, it is also possible to initially lay the pulp onto a perforated substrate, which also functions as a printer screen. The formed wet web is dewatered and preferably thermally pre-dried to a fiber density of about 40% to about 80%. Dewatering can be done with suction cupboards or other vacuum devices or with blow dryers. The imprint of the screen sieve of the printer screen is pressed into the web as described above before the web is completely dried. One way to do this is to use mechanical pressing. This can be done, for example, by pressing the roller provided with the printer screen against the drying surface of the dryer drum, such as the Yankee dryer, while the paper web is located between the feed roller and the drum dryer. Preferably, the web is pressed against the printer screen before it is · ·

- 27 would be perfectly tightened using hydrostatic pressure, a vacuum device such as a suction cup or a blow dryer. Hydrostatic pressure can be applied to create pressure in compacted zones during initial dewatering, in a separate process step, or in combination.

Non-pressed, non-pattern compacted silk crepe paper structures are disclosed in U.S. Patent Nos. 3,812,000 and 4,208,459. Non-pressed, non-pattern compacted silk crepe paper structures are generally made by layering the pulp to a perforated forming screen, such as a Fourdrinier screen, to form a wet paper web, to remove water from the web and to remove any residue. the web having a fiber density of at least 80% and then creping the web. Water is removed from the paper web by vacuum dewatering and drying in a thermal post. The structure thus obtained is soft but weak, having a high specific volume of iv which consists of relatively uncompressed fibers. Preferably, a binder is added to the portions of the web before creping.

The silk crepe paper webs of the present invention can be used wherever soft, absorbent silk crepe paper webs are required. The tissue paper webs of the present invention are particularly advantageous for use in the manufacture of paper towels, toilet paper and facial tissue products. Thus, for example, two silk crepe

paper tape can be pressed and bonded to one another with a binder as described in U.S. Patent 3,414,459 for the production of two elemental paper towels.

Determination of molecular weight

A. Introduction

A key distinguishing feature of polymeric materials is their molecular size. The properties which enabled the polymers to be used in a variety of applications are almost exclusively due to their macromolecular nature. In order to fully characterize these materials, it is essential that we have methods for the definition and determination of their molecular weights and molecular weights. It is preferable to use the term relative molecular weight rather than molecular weight, although 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 is gaining ground. Rather, molecular size is expressed as molecular weight averages.

B. Molecular Weight Averages

Assuming a simple molecular weight distribution representing the mass fraction of molecules having a relative molecular weight, some useful average values can be defined. Averaging based on the number of special mass specimens / N ^ /, the average molecule • ·

- 29 mass numbers are obtained:

£ N.M.

n = -------- έΝ.

An important consequence of this definition is that the average molecular weight in grams gives the Avogadro number of molecules. This definition of molecular weight refers to monodisperse species, i.e., molecules of the same molecular weight. Of greater importance is the recognition that if the number of molecules in a given mass of a polydisperse polymer can be determined in some way, then n can be easily calculated. This is the basis for measuring colligative property.

By averaging based on the weight fraction of molecules in a given mass, this leads to the definition of weighted average molecular weights.

£ WN <NM ²

11 ^ 11 w „------- = -------- <W. <N.M.

z. 11 1 w is much more useful for expressing polymer molecular weights than n because it more accurately reflects certain properties such as melt viscosity and the mechanical properties of polymers and is therefore used in the present invention.

Analytical and test procedures

The amount of chemicals used in the process to treat the paper or retained by the webs of crepe paper can be analyzed by any method known in the art.

A. Quantitative analysis of the quaternary ammonium compound and the polyhydroxy compound

The amount of quaternary ammonium compound retained by the crepe paper, such as di / hydrogenated / tallow alkyl dimethylammonium methyl sulfate (DHTDMAMS), can be determined by subjecting the DHTDMAMS to an organic solvent extraction with bromide followed by dimide extraction. using anionic / cationic titration. The amount of the polyhydroxy compound, such as PEG-400, can be determined by extraction with an aqueous solvent, such as water, and then the amount of PEG-400 in the extract is determined by gas chromatography or colorimetry. These methods are exemplary only and do not exclude the use of other methods that can be used to determine the amount of special components retained by the tissue paper.

B. Hydrophilicity / Absorption /

The hydrophilicity of the tissue paper generally indicates the tendency of the paper to become wet with water. The hydrophilicity of the tissue paper can be expressed quantitatively by determining the time required for the dry paper to be completely moistened with water. This period is wetting! called time. In order to provide a suitable and repeatable test of the wetting time, the following procedure may be used to determine the wetting time: first, an approx.

·· · ··

11.1 x 12 cm conditioned unit sample / for paper samples at ambient conditions of 23 + 1 ° C and 50 + 2% relative humidity as required by TAPPI Method T 402 /; secondly, the flask is folded into four adjacent quarters and then folded into a scoop of about 1.9 cm to about 2.5 cm in diameter; third, placing the scooped drink on the surface of a distilled body of water at 23 + 1 ° C and simultaneously triggering a control clock; fourth, the clock is stopped and read when the dampening of the IV drip is complete. Total wetting is determined visually.

Of course, the hydrophilicity properties of the silk crepe papers of the present invention can be determined immediately after manufacture. However, there may be a significant increase in hydrophobicity within the first two weeks after the production of the tissue paper, that is, after two weeks of production. Therefore, the wetting! times are preferably measured at the end of the two-week period. Wetting at room temperature at the end of the two-week aging period! times are called two-week wetting times.

C. Density

The density of crepe paper as used in this description is the average density calculated by dividing the weight of the paper by

The caliper is the thickness of the paper that is obtained when the paper is subjected to a weight of 15.5 g / cm.

- 32 Optional components

Other chemicals commonly used in papermaking may be added to the substantially anhydrous, self-emulsifying chemical softener composition or papermaking pulp described above, as long as they do not significantly and adversely affect the softness and absorbency of the fibrous material and enhance the chemical softener.

For example, surfactants may be used to treat the webs of silk crepe paper according to the invention. When used, the amount of surfactant is preferably from about 0.01% to about 2.0% by weight based on the dry weight of the paper. The surfactants preferably have alkyl chains of eight or more carbon atoms. Suitable anionic surfactants include, for example, linear alkyl sulfonates and alkyl benzene sulfonates. Nonionic surfactants include, for example, alkyl glycosides, including alkyl glycoside esters such as Crodesta SL-40, product of Croda, Inc., New York, NY; alkyl glycoside ethers disclosed in U.S. Patent 4,011,389; and alkyl polyethoxylated esters such as Pegosperse 200 ML, a product of Glyco Chemicals, Inc., of Greenwich, CT, and IGEPAL RC-520, available from Rhone Poulenc Corporation, Cranbury, N.J.

Other types of chemicals that can be included are dry strength additives that increase the tensile strength of the webs of silk crepe paper. Examples of dry strength enhancing additives are carboxymethylcellulose and cationic polymers of the ACCO chemical family, such as ACCO 711 and ACCO 514; the ACCO chemical family is preferred.

These materials are commercially available from American Cyanamid

Company of Wayne, New Jersey. When used as a dry strength additive, it is preferably present in an amount of from about 0.01 to about 1.0% by weight based on the dry weight of the crepe paper.

Other types of chemicals that can be included are wet strength additives that improve the wet tear of the silk crepe papers. According to the invention, the paper may optionally contain from about 0.01% to about 3.0% by weight, more preferably from about 0.3% to about 1.5% by weight, of water soluble permanent wet strength resin, based on the weight of the dry fiber.

Permanent wet strength resins useful in the present case can be of various types. Generally, resins that have already been used in papermaking and will continue to be used can be used. Numerous examples of these are described in Westfelt's prior art reference.

Typically, wet strength resins are water soluble, cationic materials. That is, the resins are water-soluble at the time they are added to the papermaking pulp. However, it is possible, and even expected, that events such as crosslinking will render the resin insoluble in water. Some resins are also specific. · ···················································•••

- it dissolves under 34 conditions, thus above a limited pH range.

Generally, wet strength resins are likely to undergo crosslinking or other hardening reactions after being placed on or between the papermaking fibers. Crosslinking or hardening usually does not occur until a significant amount of water is present.

Various polyamide-epichlorohydrin resins are particularly useful. These materials are low molecular weight polymers with reactive functional groups such as amino, epoxy and azetidinium. The patent literature is full of methods for preparing such materials.

Examples are U.S. Patent Nos. 3,700,623 and 3,772,076.

Polyamide epichlorohydrin resins sold by Hercules Incorporated of Wilmington, Delaware under the trademarks Kymené 557H and Kymene 2064 are particularly useful for the silk crepe papers of the present invention. These resins are generally described in the above two patents.

Base-activated polyamide-epichlorohydrin resins for use in the silk crepe papers of the present invention are sold by the Monsanto Company of St. Louis, Missouri under the trade name Santo Slit, thus known as Santo Slit 31. Substances of this type are generally described in U.S. Patent Nos. 3,855,158, 3,899,388, 4,129,528, 4,147,586, and 4,222,921.

• · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ···

Other water-soluble cationic resins useful in the present case are polyacrylamide resins marketed under the tradenames Parez, thus Parez, and Parez 631NC by the American Cynamid Company of Stanford, Connecticut. These materials are generally described in U.S. Patent Nos. 3,556,932 and 3,556,933.

Other types of water-soluble resins useful in the present invention include acrylic emulsions and anionic styrene-butadiene latexes. Several examples of such types of resins are disclosed in U.S. Patent No. 3,844,880.

Still other water-soluble cationic resins useful for the present invention are urea-formaldehyde and melamine-formaldehyde resins. These polyfunctional reactive polymers have molecular weights of a few thousand. Typical functional groups include nitrogen-containing groups such as amino groups and nitrogen-linked methylol groups.

Polyethyleneimine type resins, although less preferred, may also be used in the present case.

A more complete description of the above-mentioned water-soluble resins, including their preparation, can be found in ['’']. Monograph Series No. 29, Wet Strength In Paper and Paperboard, Technical Association of Pulp · and Paper Industry / New York; 1965 / J. The term "permanently wet strength resin" as used herein refers to a resin which, when placed on an aqueous medium, allows most of its initial wet strength to be obtained by placing the paper on an aqueous medium.

- 36 hold for at least 2 minutes.

The above-mentioned wet strength additives generally improve the permanent wet strength of the paper products, i.e., when the paper is placed in an aqueous medium, it retains a significant portion of its initial wet strength for a period of time. However, permanent wet strength may be necessary and undesirable in some pairr types. Certain paper products, such as toilet paper, etc. usually discarded after short periods of use in sewage systems and the like. These systems can become clogged if the paper product retains its hydrolysis-resistant strength properties for a long time. Recently, manufacturers have added periodic wet strength additives to paper products that have sufficient wet strength for their intended use but will deteriorate as the paper is soaked with water. Wet strength deterioration facilitates the passage of paper product through sewage systems.

Suitable periodic wet strength resins are, for example, modified starch periodic wet strength materials such as National Starch 78-0080 sold by National Starch and Chemical Corporation of New York, NY. Wet strength agents of this type may be prepared by reaction of dimethoxyethyl N-methyl chloroacetamide with cationic starch polymers. Modified starch modified wet strength agents are also described in U.S. Patent No. 4,675,394. Preferred periodic wet strength resins are disclosed in U.S. Pat. No. 4,981,557. · · · · · · · · · · · · · · ·

- 37 patents.

In view of the above classes and specific examples of both permanent and intermittent wet strength resins, it should be noted that the listed resins are exemplary only and are not intended to limit the scope of the invention.

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

The above list of optional chemical additives is also by way of example only and is not intended to limit the scope of the invention.

The following examples illustrate the practice of the present invention, also by way of limitation thereof.

The purpose of this example is to illustrate a process that can be used to prepare a substantially anhydrous, self-emulsifying chemical plasticizer containing a mixture of di / hydrogenated / tallow alkyl dimethylammonium methyl sulfate (DHTDMAMS) and polyoxyethylene glycol 400 / PEG-400.

The anhydrous, self-emulsifying chemical softener composition is prepared by the following method: 1. weighing an equivalent amount of DHTDMAMS and PEG-400 separately;

2. heating the PEG to about 66 ° C; 3. dissolving the DHTDMAMS in .PEG to form a melt solution at 66 ° C; (4) using a suitable blend to form a homogeneous mixture of DHTDMAMS and PEG; 5. cooling the homogeneous mixture to room temperature to give a solid.

The substantially anhydrous, self-emulsifying chemical softener composition of claim 5 may be premixed / as described in any of claims 1-5 above. according to operations (in a chemical plant (e.g., Sherex Company of Dublin, Ohio)) and then economically delivered to the end user of the chemical softener composition, where it can be diluted to the desired concentration.

2 _r _example

The purpose of this example is to illustrate a process that can be used to prepare a substantially anhydrous self-emulsifying chemical softener composition comprising a mixture of di / hydrogenated / tallow alkyl dimethyl ammonium sulfate (DHTDMAMS) and a mixture of glycerol and PEG-4OO.

The substantially anhydrous, self-emulsifying chemical softener composition is prepared by the following process; 1) mixing a 75:25 weight ratio of glycerol and PEG-400;

2. weighing the equivalent weights of the DHTDMAMS and the mixture of claim 1 separately; 3) heating the mixture of 1 to about 66 ° C; 4) dissolving the DHTDMAMS in the mixture of 3 to form a melt solution at 66 ° C; 5. using a suitable blend to form a homogeneous mixture of DHTDMAMS in the mixture of 3; 6. cooling the homogeneous mixture of 5 to room temperature to obtain a solid form.

The substantially anhydrous, self-emulsifying chemical softener composition of claim 6 may be premixed / as described in claims 1-6 above.

operations / in a chemical plant / such as Sherex ·· ···· · · · · · · · · · · · · · · · · · · · · · · · ·

Company of Dublin, Ohio, and can then be delivered economically to the end user of the chemical softener formulation, where it can be diluted to the desired concentration.

3 _i __gélda

The purpose of this example is to illustrate a process for producing a soft and absorbent paper towel blend using a substantially dry, self-emulsifying chemical plasticizer composition which is di / hydrogenated / tallowalkyldimethylammonium / DMSO / DMSO / DMSO / DMSO / D / It contains the PEG-400 / premix in solid state and also contains a permanent wet strength resin.

In the practice of the invention, a half-size Fourdrinier papermaking machine is used.

First, a substantially anhydrous, self-emulsifying plasticizer formulation is prepared as in Example 1. A homogeneous solid pre-mix of DHTDMAMS and PEG-400 was dispersed in a water-conditioned water tank at 66 ° C to form a submicron vesicle dispersion. The particle size of the vesicle dispersion was determined using an optical microscope. The granular clay. in the range of about 0.1 to about 1.0 microns. Figure 3 is a cryo-transmission micrograph of a vesicle dispersion of a 1: 1 by weight DHTDMAMS and PEG-400 system (X 63,000). Figure 3 shows that the membranes of the particles have one or two bilayer thicknesses, the geometry of which is from closed / open vesicles to lamellar structures. · · · · · · · · · · · · · · · · · · · · · · · · · · · · and covers.

Second, a 3% by weight aqueous NSK suspension (NSK = northern softwood kraft pulp = northern softwood kraft pulp) was prepared in a conventional pulp pulp. The NSK slurry is slightly refined and is supplied by Hercules Incorporated of Wilmington, DE, a 2% solution of permanent wet strength resin such as Kymene 557H, into the NSK conduit at a weight of 1% by weight on dry fibers. The absorption of Kymene 557H onto NSK fibers is facilitated by a paper machine / in-line / mixer. After the mixer, a 1% carboxymethylcellulose solution was introduced at 0.2% by weight on dry fibers to increase the dry strength of the fibrous substrate. The absorption of carboxymethyl cellulose onto NSK fibers can be facilitated by a papermaking mixer. A 1% solution of the chemical softener mixture / DHTDMAMS / PEG / NSK slurry is then added to the dry fibers in a 0.1% weight ratio. The absorption of the chemical softener mixture onto the NSK fibers can also be facilitated by a paper machine mixer. The NSK slurry was diluted to 0.2% with a propeller pump.

Third, in a conventional pulp pulp, a 3% by weight aqueous CTMP slurry is prepared (CTMP = chemically modified thermomechanical pulp). 0.2% by weight of the nonionic surfactant (Pegosperse), based on the dry fibers, is added to the pulping agent. A 1% chemical softener blend solution is added to the CTMP conduit, prior to the material pump, to dry fibers at 0.1% w / w. The absorption of the chemical softener mixture onto CTMP fibers can be facilitated by a paper machine mixer. The CTMP slurry was diluted to 0.2% with a propeller pump. The pulp mixture (NSK / CTMP) treated in the above manner is mixed in an overhead cabinet and layered on a Fourdrinier sieve to form an initial paper web. Dewatering is done through a Fourdrinier sieve and is assisted by a baffle and suction cups. The Fourdrinier sieve has 5 shed fine satin fabric configurations with 84 machine direction and 76 transverse monofilament yarns per inch. The initial wet paper web is transferred from the Fourdrinier screen at a transfer density of about 22% to a photopolymer screen having 240 linear Idaho cells per square inch, 34% screen knot area, and a photopolymer depth of 14 mil. The linear Idaho name is based on the fact that the cross-section of the wires from which the sample originated originally resembled that of a potato. However, the walls of the wires are generally straight on four sides, so the pattern is referred to as Idaho linear, not simply as Idaho pattern. Further dewatering is performed by vacuum assisted water extraction until the fiber density of the paper web reaches 28%. The sample web is pre-dried by air blowing to a fiber density of about 65% by weight. The web is then glued to a drying surface of a Yankee with a sprayed creping adhesive consisting of 0.25% aqueous polyvinyl alcohol solution. Increase the fiber density to about 96% and then dry the paper strip with a scraper blade • · · ·

- 42 crepe. The scraper blade has an incline of about 25 ° and is positioned relative to the Yankee dryer with an inlet angle of about 81 °. The Yankee dryer is operated at approximately 244 meters / minute. The dry web is rolled at a speed of 214 meters per minute.

From the two elemental layers of the web, paper towels are formed by pressing and assembling them using a polyvinyl alcohol adhesive. The paper towel has a basis weight of about 26 µM / 929.03 cm / 0.2% substantially anhydrous, self-emulsifying chemical softener, and about 1.0% permanent wet strength resin. The paper towel so produced is soft, absorbent and very moist when wet.

.._example

The purpose of this example is to illustrate a process using permeable drying and layered papermaking methods to produce soft and absorbent toilet paper which is di / hydrogenated / tallow alkyl dimethyl ammonium methyl sulfate / DHTDMAMS / 400 / polyoxyethylene / and a substantially anhydrous, self-emulsifying chemical softener composition comprising a liquid premix and an intermittent wet strength resin.

In the practice of the invention, a half-size Fourdrinier papermaking machine is used.

First, a substantially anhydrous, self-emulsifying chemical plasticizer is prepared according to the procedure described in Example 1.

- 43 preparations. The solid pre-blend of DHTDMAMS and polyhydroxy compound was thawed at about 66 ° C. The molten mixture is then dispersed in a water tank conditioned at 66 ° C to form a submicron vesicle dispersion. The particle size of the vesicle dispersion was determined using an optical microscope. The particle size is about 0.1 to 1.0 microns. Figure 4 is a cryo-transmission micrograph of a vesicle dispersion of a 1: 1 weight ratio DHTDMAMS to a polyhydroxy compound system (X 63,000). Figure 4 shows that the membranes of the particles have one or two bilayer thicknesses whose geometry extends from closed / open vesicles to plate-like structures and sheets.

Second, a 3% w / w aqueous suspension of NSK is prepared in a conventional pulverizer. The NSK slurry is slightly cleaned / refined and a 2% solution of a periodic wet strength resin / National starch 78-0080, a product of the National Starch and Chemical Corporation of New York, NY, is introduced into the NSK conduit onto dry fibers. 0.75% by weight. The absorption of the intermittent wet strength resin onto NSK fibers is promoted by a paper machine mixer. The NSK slurry was diluted to a density of about 0.2% using a propeller pump.

Third, a 3 wt% aqueous suspension of eucalyptus fibers is prepared in a conventional pulp blower. A 1% solution of the chemical softener mixture is introduced into the material line of the eucalyptus suspension before the material pump,

· Dry 0.2% by weight. The absorption of the substantially anhydrous self-emulsifying chemical softener blend onto eucalyptus fibers can be facilitated by a papermaking mixer. The eucalyptus fiber suspension is diluted with a propeller pump to a density of about 0.2%.

The so treated pulp mixture / 30% NSK / 70% eucalyptus / overhead is mixed and layered on a Fourdrinier sieve to form an initial web. Dewatering is done through the Fourdrinier sieve and is assisted by a baffle and suction cups. The Fourdrinier sieve has a 5 shed fineness satin fabric configuration, containing 84 machine direction and 76 transverse monofilament yarns per inch.

The initial strip of paper from the Fourdrinier sieve, at the transfer point, was transferred to a photopolymer sieve containing 562 linear Idaho cells per square inch, 40% screen knot area, and 9 µm photopolymer depth. Further dewatering is performed by vacuum assisted water extraction until the web has a fiber density of about 28%. The sample web is pre-dried by air blowing to a fiber density of about 65% by weight. The web is then glued to a drying surface of a Yankee by spraying with a creping adhesive consisting of 0.25% aqueous polyvinyl alcohol solution. The fiber density is increased to about 96%, and the web is creped dry with a scraper knife. The scraper blade has an angle of about 25 ° and is positioned relative to the Yankee dryer ·· * ·

- 45 have an entry angle of about 81 °. The Yankee dryer is operated at approximately 244 meters / minute. The dry web is rolled at a speed of 214 meters per minute.

The web is processed into a single-ply silk crepe paper product. The paper has a basis weight of about 18 U / 3M. per square foot, containing about 0.1% chemical softener mixture and about 0.2% periodic wet strength resin. It is important that the silk crepe paper so prepared is soft, absorbent and suitable for face and / or toilet paper.

S ^ -example

The purpose of this example is to illustrate a process using a translucent drying papermaking method to produce soft and absorbent toilet paper which is di / hydrogenated / tallow alkyl dimethylammonium chloride / DHTDMAC / polyhydroxy compound / glycerol / PEG7 is treated with a substantially anhydrous, self-emulsifying chemical softener composition comprising a premix of Form I and a dry strength resin.

In the practice of the invention, a half-size Fourdrinier papermaking machine is used.

First, the method described in Example 2 is used to prepare a substantially anhydrous, self-emulsifying chemical softener composition. A solid homogeneous premix of DHTDMAC and polyhydroxy compounds is thawed at about 66 ° C. The thawed mixture is dispersed in a water tank conditioned at 66 ° C to form a submicron vesicle dispersion. The particle size of the vesicle dispersion was determined using an optical microscope. The particle size is about 0.1 to 1.0 microns. Figure 5 is a cryo-transmission micrograph of a vesicle dispersion of a 1: 1 weight ratio system of DHTDMAC and polyhydroxy compounds (X 63,000). Figure 5 shows that the membranes of the particles have one or two bilayer thicknesses whose geometry extends from closed / open vesicles to plate-like structures and sheets.

Second, a 3% w / w aqueous suspension of NSK is prepared in a conventional pulverizer. The NSK slurry is slightly purified / refined and a dry strength resin (Acco 514 or Acco 711), a 2% solution of the American Cyanamid Company of Fairfield, Ohio, is added to the NSK conduit at 0.2% of dry fiber. by weight. The absorption of the dry strength resin onto NSK fibers is promoted by a paper machine mixer. The NSK slurry was diluted with a propeller pump to a fiber density of about 0.2%.

Third, a 3 wt% aqueous suspension of eucalyptus fibers is prepared in a conventional pulp blower. A 1% solution of the chemical softener mixture is introduced into the material line of the eucalyptus slurry, before the material pump, at 0.2% by weight on dry fibers. The absorption of the substantially anhydrous self-emulsifying chemical softener blend onto eucalyptus fibers can be facilitated by a papermaking mixer.

• ·

The eucalyptus fiber suspension was diluted with a propeller pump to a density of about 0.2%.

The so treated pulp mixture / 30% NSK / 70% eucalyptus / overhead is mixed and layered on a Fourdrinier sieve to form an initial web. Dewatering is done through the Fourdrinier sieve and is assisted by a baffle and suction cups. The Fourdrinier sieve has a 5 shed fineness satin fabric configuration, containing 84 machine direction and 76 transverse monofilament yarns per inch.

The initial strip of paper from the Fourdrinier sieve, at the transfer point, was transferred to a photopolymer sieve containing 562 linear Idaho cells per square inch, 40% screen knot area, and 9 µm photopolymer depth. Further dewatering is performed by vacuum assisted water extraction until the web has a fiber density of about 28%. The sample web is pre-dried by air blowing to a fiber density of about 65% by weight. The web is then glued to the surface of a Yankee dryer by spraying with a creping adhesive consisting of 0.25% aqueous polyvinyl alcohol solution. The fiber density is increased to about 96%, and the web is creped dry with a scraper knife. The scraper blade has an incline of about 25 ° and is positioned relative to the Yankee dryer with an inlet angle of about 81 °; The Yankee dryer is operated at a speed of approximately 244 meters / minute. The dry web is rolled at 214 meters per minute.

• · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · frame · frame login

- 48 We make silk crepe paper products from the two elemental layers of the web and bind them together using a layer binding method. The crepe paper has a basis weight of about 23 µm (929.03 cm) per square foot and contains about 0.1% substantially anhydrous, self-emulsifying chemical softener, and about 0.1% dry strength resin. It is important that the tissue paper produced is soft, absorbent and corresponds to facial tissue and / or toilet paper.

6 ^ _gélda

The purpose of this example is to illustrate a process using a conventional drying papermaking process to produce soft and absorbent toilet paper which is di / hydrogenated / tallow alkyl dimethyl ammonium methyl sulfate / DHTDMAMS / and polyoxyethylene glycol 400 / PEG is treated with a substantially anhydrous, self-emulsifying chemical softener composition comprising a premix and a dry strength resin.

In the practice of the invention, a half-size Fourdrinier papermaking machine is used.

First, a substantially anhydrous, self-emulsifying chemical softener composition is prepared according to the procedure described in Example 1. A solid homogeneous premix of DHTDMAMS and PEG-400 is dispersed in a water-conditioned water tank at 66 ° C to form a submicron vesicle dispersion. The particle size of the vesicle dispersion was determined using an optical microscope. The particle size is about • ·

49 0.1-1.0 microns. Figure 3 is a cryo-transmission micrograph of a vesicle dispersion of a 1: 1 by weight DHTDMAMS and PEG-400 system (X 63,000). Figure 3 shows that the membranes of the particles have one or two bilayer thicknesses whose geometry extends from closed / open vesicles to plate-like structures and sheets.

Second, a 3% w / w aqueous suspension of NSK is prepared in a conventional pulverizer. The NSK slurry is slightly purified / refined and a dry strength resin (Acco 514, Acco 711) is supplied to the NSK slurry material line by adding a 2% solution of the American Cyanamid Company of Wayne, New Jersey, to 0% dry fiber. 2% by weight. The absorption of the dry strength resin onto NSK fibers is promoted by a paper machine mixer. The NSK suspension was diluted with a propeller pump to a fiber density of about 0.2%.

Third, a 3 wt% aqueous suspension of eucalyptus fibers is prepared in a conventional pulp blower. A 1% solution of the chemical softener mixture is introduced into the material line of the eucalyptus slurry prior to the material pump in an amount of 0.2% by weight based on the dry fibers. The absorption of the chemical softener mixture onto the eucalyptus fibers can be facilitated by a paper machine mixer. The eucalyptus fiber suspension is diluted with a propeller pump to a density of about 0.2%.

The so-treated pulp mixture / 30% NSK / 70% eucalyptus / overhead is mixed and layered on a Fourdrinier sieve to form an initial paper web. Dewatering is done through the Fourdrinier sieve and is assisted by a baffle and suction cups. The Fourdrinier sieve is a shed fineness satin fabric configuration that includes 84 machine direction and 76 transverse monofilament yarns per inch. The initial web is transferred from the Fourdrinier screen to a conventional felt with a fiber density of about 15% at the transfer point. Further dewatering is performed by vacuum assisted water extraction until the web has a fiber density of about 35%. The paper tape is then glued to the surface of a Yankee dryer. The fiber density is increased to about 96%, and the web is creped dry with a scraper knife. The scraper blade has an incline of about 25 ° and is positioned relative to the Yankee dryer with an inlet angle of about 81 °. The Yankee dryer is operated at a speed of approximately 244 meters / minute. The dry web is rolled at a speed of 214 meters per minute.

Silk crepe paper products are made from two elemental layers of the web and laminated by a laminate bonding process. The crepe paper has a basis weight of about 3M square feet (929.03 cm) and about 0.1% substantially anhydrous, self-emulsifying chemical softener and about 0.1% dry strength resin. It is important that the tissue paper produced is soft, absorbent and suitable for use with facial tissue and / or toilet paper.

Claims (10)

Claims A substantially anhydrous, self-emulsifying chemical plasticizer composition comprising a mixture of a quaternary ammonium compound of formula (I), wherein each substituent is a C 1-6 alkyl or hydroxyalkyl group, or a mixture thereof, preferably a C 1-3 carbon atom. alkyl, most preferably methyl; each R 1 substituent is C 14 -C 22 hydrocarbon or a mixture thereof, preferably C 16 -C 18 alkyl; and a suitable anion, preferably chloride or methyl sulfate; and b / a polyhydroxy compound such as glycerol, polyglycerols having a weight average molecular weight of 150-800 or polyoxyethylene glycols or polyoxypropylene glycols having a weight average molecular weight of 200-4000, preferably 200-1000, most preferably 200-600; the weight ratio of the quaternary ammonium compound to the polyhydroxy compound in the mixture is from 1: 0.1 to 0.1: 1, preferably from 1: 0.3 to 0.3: 1, most preferably from 1: 0.7 to 0.7: 1, in addition, the polyhydroxy compound is mixed with the quaternary ammonium compound at a temperature at which the quaternary ammonium compound and the polyhydroxy compound are miscible and the chemical softener composition has a moisture content of less than 20% by weight. 2. A substantially anhydrous according to claim 1, which is essentially anhydrous. - 52 self-emulsifying chemical plasticizers which are stable, homogeneous solids or viscous liquids at temperatures of 20 ° C or higher. The substantially anhydrous, self-emulsifying chemical plasticizer composition according to claim 1 or 2, wherein the quaternary ammonium compound is di / hydrogenated / tallow alkyl alkyl dimethyl ammonium chloride or di / hydrogenated / tallow alkyl dimethyl ammonium methyl sulfate. . 4. The substantially anhydrous, self-emulsifying chemical plasticizer composition according to any one of claims 1 to 5, wherein the quaternary ammonium compound and the polyhydroxy compound are mixed at a temperature of at least 40 ° C, preferably 56 to 68 ° C. 5. The substantially anhydrous, self-emulsifying chemical softener composition of any one of claims 1 to 5, wherein the quaternary ammonium compound is in a liquid crystal state or in a liquid state when mixed with the polyhydroxy compound. 6. An aqueous dispersion according to claims 1-5. A substantially anhydrous, self-emulsifying chemical softener composition according to any one of claims 1 to 6, and comprising an aqueous medium in which a homogeneous mixture of quaternary ammonium compound and polyhydroxy compound is self-dispersed to form a submicron vesicle dispersion. The aqueous dispersion of claim 6, wherein the aqueous medium has a temperature of at least 20 ° C. The aqueous dispersion according to claim 6 or 7, wherein the homogeneous mixture of the quaternary ammonium compound and the polyhydroxy compound is in a solid state before being dispersed in the aqueous medium. The aqueous dispersion according to claim 5 or 7, wherein the homogeneous mixture of the quaternary ammonium compound and the polyhydroxy compound is in a liquid state before being dispersed in the aqueous medium. 10. A substantially anhydrous, self-emulsifying chemical plasticizer composition according to any one of claims 1 to 4, having a moisture content of less than 10% by weight.