MXPA01006413A - Wet-creped, imprinted paper web - Google Patents

Abstract

A low density, wet-creped paper web having improved levels of tensile strength, tear strength and thickness. The web has a distribution of densified regions corresponding to the distribution of knuckles on a drying fabric. Generally speaking, these densified regions should be distributed so that the distance between at least a portion ofthe densified regions is less than or equal to the length of the longest fiber in the furnish (e.g., pulp fibers and/or other fibers) used to make the paper web. The wet-creped paper web is removed from a Yankee dryer at a dryness of between 45 and 65%and then passed to the after dryer section of a paper machine. An after dryer fabric is pressed into the wet base web to transfer the topography of the after dryer fabric to the web and to generate improved tensile strength, tear strength and thickness. The wet base web is pressed into the drying fabric utilizing a nip before the web is 70%dry. Once the wet base web initially contacts the drying fabric, it should remain on the drying fabric without any change in the registration between the wet base web and the drying fabric until the base web is at least about 80%dry.

Description

PRINTED PAPER FABRIC CREAMED IN HUMID FIELD OF THE INVENTION The present invention relates generally to wet creped fabrics for paper towel and tissue, and more particularly to methods for making wet creped fabrics having a printed pattern.

SYNTHESIS OF THE INVENTION It is an object of the present invention to provide a base fabric of low density paper for towels and tissues of a wet creped fabric as well as a process for making such a fabric.

It is a further object of the present invention to provide a low density paper-based fabric with improved tensile strength, improved tear strength and thickness as well as a process for making such a fabric.

It is a feature of the present invention to provide a base fabric of low density paper having a densification pattern there, wherein the fines are concentrated in the densifications as well as a process for making such a fabric.

Another feature of the present invention is to provide a base fabric of low density paper and fabrics having a density pattern where the chemicals added to the supply are concentrated on a surface of the finished fabric and particularly on a surface of the densifications. . Also, it is a feature of the present invention to provide a process for drying a base fabric of low density paper for towels and tissues having a pattern of densifications where the chemicals added to the supply are migrated so that they concentrate on a surface of the finished fabric particularly, on a surface of the densifications.

Briefly stated these and numerous other features, objects and advantages of the present invention will readily become apparent from the reading of the detailed description, claims and drawings herein established.

In accordance with the invention, a wet crepe fabric is removed from a Yankee dryer at 45 to 65% dryness. Desirably, the wet crepe fabric is removed at a drying rate ranging from about 50 to about 60%. The fabric is then passed to the dryer section after the paper machine.

A feature of the invention is the pre-a subsequent dryer fabric in the wet base fabric transfer the topography of the fabric back dryer and to generate improved tensile strength, tear strength and improved thickness.

The wet base is pressed in the dried tea using a pressure point before the fabric is 70% dry. Desirably, this pressing step occurs to tissue dryness ranging from about 45 to about 65%. More desirably, this pressing step occurs to tissue dryness when from about 50 to about 60%.

The pressing of the wet base fabric into a dryer fabric can be achieved by using a press roll d such as a steel roll which is supported by a soft roll such as a rubber roll. That is, the steel rod makes contact with the rear dryer fabric and the rear dryer fabric in the base fabric which is supported or supported by the rubber roller. Alternatively a soft press roll (eg, a rubber press roll) can make contact with the posterio dryer cloth by pressing the fabric of the rear dryer into the base fabric which is backed or supported by a hard roller (eg, a roller of steel). In yet another alternative, soft press roll (e.g., a rubber press roll) can be used to make contact with the subsequent dryer fabric and press the subsequent drying cloth and base fabric which is supported by a dryer such as , example, a Yankee dryer, a heated drum and / or a steam bot. In such an embodiment, the drier canister will be sufficiently robust to withstand the load of the press roll. The load on the rollers can be varied to obtain the desired conformation of the weave to the wire so that the topography of the wire is transferred to the weave. Desirably, this transfer of the topography of the woven wire will be substantial.

As an example, the load on the rollers p is sufficient to produce a pressure at the fastening point of from about 10 to about 400 pounds per square inch. As a further example, the load on the rollers may be sufficient to produce a pressure at the clamping point of from about 15 to about 100 pounds linear inch. As a further example, the load on rollers may be sufficient to produce a clamping point pressure of from about 20 to about pounds per linear inch.

According to the invention, once the wet base fabric initially makes contact with the drying fabric, it must remain on the drying fabric without any change and coincidence between the wet base fabric and the dry fabric until the base fabric is at least about 80% desirably, the wet base fabric should remain on a dryer fabric until it is about 95% dry.

In one embodiment of the invention, a drying can or a series of drying cans can be used to dry the wet base fabric. The terms "can drying" "drying cans" are used herein to refer to and include Yankee dryers and other heated, rotating, solid-surface drums such as, for example, vap cans, electrically heated or fire-heated drums. gas, rear dryer fabric is used to hold the fabric against the dryer cans The rear dryer fabric can be spun in a mode or configuration in which the fabric and fabric make contact and the matching is maintained until the fabric is essentially dry ( at least around dry.) Generally speaking, the term "dry" or "dryness" refers to an average dryness of the tissue at the measurement point and is a ratio of dry fiber weight to total tissue weight (fibers and water) At the point of measurement Desirably, a single dryer fabric can be used to carry the fabric.In such incorporation, the fabric can traverse the dryer cans in a sudden pattern so that fabric makes Use the dryer fabric and stay in contact with the dryer fabric until the fabric is essentially s The present invention encompasses a low density wet crepe p woven having improved levels of tensile strength, tear resistance and gr made according to the process described above.

In one embodiment, the wet-woven and low-density paper fabric has a distribution of densified regions corresponding to the distribution of the nudi on the dryer fabric. Generally speaking, these densified regions should be distributed so that the distance between at least a part of the densified regions less than or equal to the length of the longest fiber in supply (for example, pulp fibers and / or other fib Desirably, the densified regions should be distributed so that the distance between at least a portion of the densified regions is less than the average fiber length supply (eg, pulp fibers and / or other fibers) the supply used to make the paper tissue.

The densified regions will generally have improved strength and increase the overall tissue strength of the paper. The parts of the paper fabric outside densified regions will generally have much lower densities. Such low density regions generally provide good water or liquid absorption.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an illustration of an apparatus for making example paper.

Figure 2 is an illustration of an exemplary press roll detail and a rear drier arrangement.

Figure 3 is an illustration of an exemplary press roll detail and a rear drier arrangement.

Figure 4 is an illustration of an exemplary press roll detail and a rear drier arrangement.

DEFINITIONS The term "average fiber length" as used herein, refers to a heavy average length of pulp fibers determined using a model analyzer of fi Kajaani model No FS-100 available from Kajaani Oy Electronics, Kajaani, Finland. According to the test procedure, sample of pulp is treated with a macerating liquid to ensure that no bunches or pieces of fiber are present. C pulp sample is disintegrated in hot water and a solution of approximately 0.001% is diluted. The individual test samples are pulled in approximately 50 to 100 milliliter portions of the diluted solution when tested using the standard Kaja fiber analysis test procedure. The average heavy fiber length can be expressed by the following equation: (x ± n / n, = 0 where k = maximum fiber length < fiber length nx = number of fibers that have length xx n = total number of medium fibers The term "low-average fiber length pulp" as used herein refers to pulp and byproducts processes for making paper containing an amount means short fibers and non-fiber particles. In many cases these materials can be difficult to form into sheets of paper and can provide non-woven fabrics or relatively tight waterproof pa sheets. The low average fiber length pulps can have an average fi length of less than about 1.2 millimeters as determined by a fiber optic analyzer, such as, for example, a Kajaani fiber analyzer model No. FS-1 (Kaajani Oy Electronics, from Kajaani, Finland). For example, pulp lengths of low average fiber may have average fiber length varying from about 0.6 1.2 millimeters. Generally speaking, most of the cellulosic or fibrous components of the solution for making pulp can be considered pulps of low average fiber length (short fibers and particles without fibers).

The term "high-averaged fiber length pulp" as used herein, refers to the pulp that contains a relatively small amount of short fibers and fiber-free particles which can give sheets of paper or relatively open and permeable woven fabrics. that applications are desirable where absorption and rapid fluid intake are important. The pulp of high average fiber length typically formed of non-secondary fibers (for example virgin). The secondary fiber pulp which has been cribed can also have a high average fiber length. High average fiber length pulps typically have an average fiber length of more than about millimeters as determined by an optical fiber analyzer such as, for example, a Kajaani fiber analyzer, model FS-100 (from Kaajani Oy Electronics, Kaajani, Finland). For example, a pulp of high average fiber length can have an average fiber length of from about millimeters to about 6 millimeters. The high average fiber length pulps of example which are wood fiber pulps include, for example, virgin softwood pulp bleached and unbleached.

The term "pulp" as used herein refers to fibers containing cellulose from natural sources such as woody and non-woody plants. Woody plants include, for example, deciduous and coniferous trees. Woody plants include, for example, cotton, flax, esparto grass, windew, straw, soft reed and bagasse.

The term "permeability" as used herein refers to the ability of a fluid, such as, for example, to pass through a material. Permeability can be expressed in units of volume per unit time per unit unit; for example (cubic feet per minute) per square foot of material (for example, (foot3 / minute / foot2) or (cfm / foot2)).

The term "fines" as used herein, refers to fiber-type particles and particles without fiber about 0.4 millimeters or less in length as determined by a fiber optic analyzer such as, for example, Kaajani fiber analyzer, model No. FS-100 (from Kaajani Electronics, from Kaajani, Finland). For example, the ends may be primarily a fibrous or cellulosic material present in the pulp of low average fiber length or high average fiber length pulp. The fines may also include some part of the ash-generating material The term "ash-generating materials" is used here, refers to components of a paper which generates an inorganic residue which remains after ignition a specimen of wood, paper or paper, as to remove fuel and volatile compounds .

The term "papermaking solution" as used herein refers to a waste of conventional pap processes that contain a substantial proportion of the pupa of low average fiber length (eg, short fibers and particles without fiber). and of ash-generating materials. The fibrous or cellulosic component of the papermaking sludge may contain more than 70 percent, by weight, pulp of low average fiber length. For example, fibrous or cellulose component of sludge to make p paper contain more than 80 percent, by weight of pulp of long fiber medium low.

DETAILED DESCRIPTION Turning first to Figure 1 there is illustrated an example papermaking process using a wet crepe weight. In the process, a head c 10 delivers a supply 12 on a forming fabric wrapped around a vacuum chest roll 16. supply may be at a fiber consistency of about 0.08% to about 0.6%, and more desirably a fiber consistency of from about 0.1% to about 0.55, and more desirably at a fiber consistency of from about 0.1% to about 0.2%. Immediately after the vacuum chest roll 16, the forming fabric 14 passes through the vacuum box 18 to further vacuum drain embryonic tissue 20.

It should be noted that the headbox time used is not critical to the practice of the method of the invention. Any head box that delivers a well-formed tej can be used. Furthermore, even when incorporations discussed here and shown in the figure use a vacuum chest roll, this is also not critical to the practice of the method of the present invention. The method can be used with chest roll formers, twin wire formers and fourdriniers as well as variations thereof.

The forming fabric 14 then passes through transfer zone 22 where the tissue 20 is transferred to a carrier felt 24. The transfer is made with the aid of a vacuum pick-up roller or a transfer shoe 26. tissue transfer from the The forming fabric 14 to the faithful carrier 24 should be made when the fabric consistency is in the range of about 18% to about 35% and desirably in the range of from about 22% to about 32%.

The fabric is then transferred from the faithful carrier 24 to a Yankee dryer 28 using a pre-vacuum roller 30. It is contemplated that other transfer mechanisms such as, for example, a transfer shoe may be employed. The fabric 20 is then dried over the dried Yankee 28 at a dryness ranging from about 4 about 70% or more desirably, to a dryness ranging from about 45 to about 65%. The fabric is then creped from the Yankee dryer 28 using conventional wet creping equipment 32. The wet creped fabric then moves without support to the posterose section 36 of the paper machine.

The fabric 20 is transferred to the nudil side of a dryer fabric 44. The dryer fabric 44 is then tom over a can dryer 34 such as a Yankee dryer or over the heated drums (e.g., steam cans, drums lit with gas, the drums electrically heated or similar).

According to the invention, the wet fabric pressed into a dryer fabric 44 using a pressure point rodi arrangement 38 before the fabric is 70% is desirably, this pressing step occurs at a fabric drying varying from around From 45 to about 6 More desirably, this pressing step occurs to tissue dryness ranging from about 50 to about 60%.

Referring now to Figure 2, in embodiment, a soft press roll (e.g., rubber press roll 100) can be used for contacting the rear dryer fabric 44 and pressing the rear dryer t 44 into the base fabric 20. which is supported by a drier can 34 such as, for example, a dry Yankee, a heated drum and / or a steam can. In incorporation, the drying may require being robust enough to support the load of the press roll.

More desirably, the pressing of the wet fabric 20 into the dryer fabric 44 can be accomplished using a soft press roll such as a rubber press roll which is supported by a hard roll such as a steel roll. Such example arrangement is illustrated in Figure 3. Referring now to Figure 3, there is shown a rubber press roll 100 which contacts fabric of the rear dryer 44 and presses the cloth of the rear dryer 44 on the base fabric 20 which is supported by a steel roller 102.

More desirably, the pressing of the wet fabric 20 into the dryer fabric 44 can be achieved using a hard press roll such as a steel roll which is supported by a soft roll such as a rubber roll. example arrangement is illustrated in Figure 4. Referring now to Figure 4, a steel roll 102 is shown to contact the rear dryer fabric 44 and press the rear dryer t 44 into the base fabric 20 which is backed or supported by a 100 rubber roller.

The load on the rollers can be varied to obtain the desired conformation of the fabric to the wire so that the topography of the wire is transferred to the fabric.

Desirably, this transfer of the topography of the woven wire will be substantial.

As an example, the load on the rollers may be sufficient to produce a pressure at the attachment point of from about 10 to about 400 pounds per square inch. As a further example, the load on the rollers may be sufficient to produce a pressure at the clamping point of from about 15 to about 100 pounds per linear inch. As a further example, the load on the rollers may be sufficient to produce a pressure at the clamping point of from about 20 to about 5 pounds per linear inch.

In such a manner, the knuckles of the dryer cloth 4 are pressed into the fabric 20 by restraining the fabric 20 against the unregistered movement relative to the dryer tel 44. In other words, the fabric 20 is placed in sandwich form between the fabric. dryer fabric 44 and canister dryer 3 with knuckles of dryer fabric 44 by printing a density pattern on fabric 20. Because dryer fabric 44 includes the recesses surrounding each knuckle preferably only the knuckles press fabric 20 into Desirably, upon leaving the rear dryer b 34, the fabric has reached a drought of at least about 80% or more, desirably from about 90% to about 97%. The fabrics can be rolled on a reel 40.

The dryer fabric 44 is a band or wire if with knuckles or protrusions projecting from the membrane. As such, the dryer fabric 44 can be a woven fabric, perforated sheet or film, a molded belt or a fabric c is taught in the patent. of the United States of America 4,529,480 granted to Trokhan. Axis drying fabrics include, but are not limited to fabrics available under Albany 5602 and Albany 121 designations from Albany Internation of the Appleton Wire Division, of Appleton, Wisconsin; and a Asten Hill 36-F available from Asten-Hill.

The dryer fabric can be sanded to increase area of the knuckles pressing against the wet fabric Desirably, the dryer fabric is used with the long knuckled side against the wet fabric.

The dryer fabric 44 is a continuous auger and therefore travels on a series of guide rollers, through a drive roller section and through a tensioner roller section and back to the transfer zone 22.

As mentioned above, the dryer fabric 44 t has a plurality of knuckles or protuberances arranged in pattern and extending therefrom. The maximum spacing between the adjacent knuckles should be about igu less than the length of the longest fiber in the supply. Most desirably, the maximum spacing between the adjacent nudi is equal to or less than the fiber length prom in the supply 12. Therefore, since the present invention is primarily directed to making a tissue towel product in a range of a basis weight of from about 8 to about grams per square meter (gsm) (e.g., from about 5.6 to about 70 pounds per ream) using the typical wood pulp supplies for those product types, knuckle spacing between the adjacent knuckles should e in the range of 2.5 millimeters or less. the area of the tissue actually pressed by the knuckles is desirably at 5% to 30% of the area of the tissue 20.

The dryer fabric 44 selected depends on desired properties in the product and the supply that is being used. If a higher volume is desired, one selects a dryer fabric 44 with large hollow spaces. This can a rough mesh fabric. On the other hand, if strength is required, one may select a dryer cloth 44 with knuckles to press the fabric or one could sand the existing knuckles to create a larger press area. You can see that an unlimited combination of geometries in the woven fabrics and endless bands can be used to produce a wide variety of fabric structures to meet specific product needs.

The wet creping process creates stretching in the machine direction where the fabric 2 also generates a fabric of a relatively low density. Minimal disruption of this structure is maintained by the present invention through the maintenance of the fabric 20 in dryer fabric 44, and in registration therewith during drying at a level of critical dryness, and preferably by completing the drying of the fabric 20.

It should be recognized that even when the fabric 20 pressed against the can dryers or sensitively through the fabric tension, the fabric is not dewatered by pressing. Because the fabric 20 remains in coincidence with the dryer fabric 44 through complete drying, the one pressing of the fabric 20 is in the knuckle areas of the dryer t 44.

The base fabric formed in the process of the present invention has surprising strength for thickness and density of the base fabric. This makes it highly suitable for manufacturing low weight base towels and low base p tissues without sacrificing quality.

The volume or thickness of the base fabric made by the processes of the present invention depends more on the t selected than on the strength or the basis weight.

There is a theory that the mode of drying, particularly the can dryer, combined with the restriction movement of the fabric, and the selective pressing of the fabric by carrier cloth are key components of the process for producing a strong weave. The drying cans evaporate the water in the wetter area of the base fabric faster than the dryer areas, thus reducing the variation of moisture in the fabric. With the can dryer, it is believed that uniform moisture in the fabric produces uniform fabric drying efforts which, in turn, help to produce a uniform and stronger base fabric. The fabric, maintained or restricted in the knuckles of the fabric and the surface of the dryer can also control the shrinkage which can also help to make a more uniform fabric.

Another important result of the drying pot process where the drying is carried out with the fabric being pressed against the dryer with the knuckled fabric, the mechanics of what happens inside the fabric during drying. As will be discussed here in Further, the increase in tissue strength properties is felt to result from the wet strength resin additive (eg, polyaminoamide epichlorohydrin) in the supply migrates to the knuckle points with the fines when drying.

With the present invention, it is contemplated that tests can be carried out using a non-substantive dye in the supply. With the tissue completely restricted during drying, the intensity of the dye is expected to be greater where the knuckles of the carrier fabric press against the dryer. This will indicate what percentage of water flows to the knuckles where it evaporates. It is believed that water will flow to the knuckles through any fingers mechanisms. The first will be due to the capillary forces which pull the water to the knuckles and the tissue in the areas with knuckles has a higher density. (finer pores). The second will be the flow of water from high concentration area (sponged areas) to lower concentration areas (knuckle areas). These two phenomena will be expected to cause the water to flow from the pressed areas of low density of the fabric to the pressed areas higher density of the fabric where it evaporates. The flow of water to the areas with knuckles can help in the densification formation in the tissue.

It is expected that dye concentrations in the knuckle areas where the dryer fabric will press the fabric against the dryer cans can be achieved as long as the fabric left by the Yankee dryer is 60% less. The intensity of the dye in the knuckles is expected to decrease essentially when the dryness of the Yankee dryer leaving fabric is increased above 60%.

With respect to the opposite side of the fabric (the weave away from the surface of the can dryer) the dye intensity on this side is expected to increase as the dryness increases leaving the Yankee dryer. a dye or color much more visible at 60% dryness leaving the Yankee dryer and exhibited an increased color as the dryness increased leaving the Yankee drying.This is thought to correspond to less water migrating to the knuckle areas of the fabric as it dries more the tissue left by the Yankee dryer.

From the above, it is generally thought that the chemicals (wet strength resins) will migrate to the knuckle area of the fabric during pot drying. This can be confirmed by carrying out iodine vapor adsorption tests on dried dried boat samples. These tests are expected to indicate that the cationic chemical (Ky 1200) will concentrate in the knuckle areas of the restricted boat sec tissue. Experience has shown that iodine concentrates by adsorption where the high electron density is. The electron density of the Kymene molecule will indicate the iodine will probably be adsorbed on the Kymene. So it is believed that the Kymene will be concentrated in the areas of nudil The migration of the Kymene during the drying of restricted boat thinks that it results in something akin to the union of pu printing of the fabric and therefore will improve the resistance of the fabric will have an impact beneficial on dry strength.

Generally speaking, chemical additives can be concentrated in the knuckle areas in two ways. Any chemical additive that is not tightly bound to paper fibs can migrate to the knuckle areas as the free fluid flows to the knuckles where it will evaporate. In addition, in the sense that it is known that fines will flow in a tej as water flows, fines are concentrated in the fine pores where the knuckles press the fabric. Because you know that fines absorb larger amounts of chemical in relation to other paper fibers because of their much larger surface area, the concentration of fines in a knuckle will also give a higher concentration of chemical additives in densifications or areas with knuckles.

The mechanics of Kymene migration (c is cationic) to the knuckled areas of the tissue through the practice of the process of the present invention should be practicable with other chemicals added to the supply. Particularly, anionic or ionic chemical dyes or additives should migrate to the surface of the fabric where fabric makes contact with the drying cans. In addition, chemical additives and dyes should be concentrated in the areas where the knuckles press tissue against the dryers. Examples of chemical additives and tin found to concentrate in densifications or knuckle areas include turbid Cibecrone non-ionic dye (manufactured by Ciba Geigy), the FD &C Blue dye # 1 (an anionic ti made by Warner Jenkins), the Blue Letter 2GL (an anionic ti made by Sandoz Chemical Company) and Acco 85 (an anionic dry resistance agent) produced by Cyanamid.

Tables 1-5 identify the data for the printed, creped, and wet paper tissues produced using the method described above. Each tab lists a variety of details about the pap tissues formed from the same supply. The supply included about 30% by weight of Pictou pulp (available from Kimberly-Cla Corporation) which is composed of about 80% per p of softwood kraft pulp from the north and about 20% weight of kraft wood pulp lasts from the north. The supply also includes about 50% by weight of fiber recycled about 20% by weight of quimotermomecánica pulp available under the trade designation Tembec CTMP 525 of Te Corporation. A Kymene 1200 wet strength resin (a poly (aminoamine) -epiclorohydr resin manufactured by Hercules) was added to the wet end in an amount of 1% dry fiber weight in the supply box.

The forming conditions and the creped conditions are identified in Tables 1-5 and are generally identical or very similar. Tab report variations in fabric strengths, thickness and other properties p different pressure point settings, different from dryer fabrics and different pressure point pressure conditions.

For the base weight data, a long piece . 5 inches of each sample was bent twice to give or creases. Four of 2.45 inches by 2.45 inches, the base weight squares of each fold were cut from each folded sample. The samples were weighed to determine the base p and an average value for the samples was determined. The base weight expressed in units of pounds per 2880 p squares (2880 square feet = ream = rm.) Or pounds / res conditioned to 50% of relative humidity and 23 degrees centigrade for 24 hours.

The thickness of the paper samples was measured at a load of 1 kilopascal (1 kPa). Each sample (even one od folds) was composed of 10 tissues and was free of duplication. The samples were tested using a Thwin Albert VIR II Thickness Tester using a 39.497 millimeters (+ 0.25 millimeter circular foot diameter at a pressure of 1 kPa and a 3-second stay time.The results expressed co millimeters / 10 tissues (as used by the consumer).

The tensile strength values given in tables 1-5 were measured by a breaking length test (TAPPI Test Method No. T494 OM-88 using a 5.08 cm sample extension and a crosshead speed of 5.08 centimeters per minute. Typically the resistances are different in the direction of the machine against the cross direction to the machine of the Also, the base weight of the samples may vary. T variation can affect the tensile strength. Therefore, a geometric mean breaking length (GMBL) is calculated for each sample. The average geometric breaking length was calculated as the quotient obtained by dividing the base weight in the square root of the product of the resistances, the tension in the machine direction and in the direction transversal to the machine. The tensile strengths measured in both the machine direction and the cross direction to the machine and the basis weight for the sample of t are measured as described above with all the units selected to result in meters of length at breaking.

GMBL (meters) = (MDT * CDT) l / 2 / BW Total Absorbed Water (TWA) of the samples determined by measuring the amount of a liquid adsorbed by the samples after being immersed in a distilled or deionized bath at approximately 23 ° C and allowed to completely moisten.

More specifically, the absorbency is determined by first cutting a 7.62 mm 7.62 mm specimen of the material to be evaluated, conditioning the sample at 23 ° C and at 50% relative humidity, and weighing specimen. This was recorded in units of grams as Wl. Drain strips should also be cut from the same material.

A standard-class reinforced stainless steel-wire wire grating was built into the liquid bath. Using the blunt edge clamps, specimen is placed in the liquid bath on the grid submerged for two minutes.

After two minutes, the specimen is placed on the grid so that it is aligned with the bottom esq of the grid. The grid is raised and the specimen is allowed to drain for a few seconds before the drainage strip is attached. The specimen with the drainage strip then attached to a specimen holder, hangs on a rod over a drainage tank and is allowed to drain for minutes. Then the specimen is detached from the specimen holder by releasing the drain clamps placed on a weighing tray of a scale. This humid sample is heavy and this weight is recorded in units of gra as in W2.

The liquid weight is obtained from the formula: Liquid Weight = W2 - Wl Absorbed Total Water (TWA) in grams per gram is obtained from the formula: TWA (g / g) = Liquid Weight / Wl From the above it can be seen that this invention is well adapted to achieve all the purposes and objects given here as set out together with other advantages which are evident and which are inherent to the process.

It will be understood that certain characteristics subcombinations are useful and can be used c reference to the other characteristics and subcombinations. It is contemplated and is within the scope of the claims.

As many possible additions, it can be made of the invention without departing from the scope thereof, it will be understood that all the matters given here were shown the accompanying drawings and that they should be interpreted as illustrative and not as in a limiting sense.

Disengager: None 0 0% Resin Level: Kymene 1200 ® 1.0% M __ Supply Yankee Spray: None ® 0% solids: 0 ce? ecc: Chest of 0 g / pr1 Disengager: None ® 0% Resin Level: Kymene 1200 ® 1.0% Level. Injection Point: Supply Chest Yankee Spray: None ® 0% solids: 0 cc / min: o g / pr ' Disengager: None ® 0% Resin Level: Kymene 1200 ® 1.0% Level. Injection Point: Sumini's Chest Yankee spray: None ® 0% solids: 0 cc / min: 0 g / m '' Disengager: None ® 0% Resin Level: Kymene 1200 ® 1.0% Level. In Lyecci's Point: Sumini's Chest Yankee Spray: None ® 0% solids: 0 ce / min: 0 g / m- 'Disbonding: None ® 0% Resin Level: Kymene 1200 ® 1.0% Level. ^ Injection Point: Supply Coffer Yankee Spray: None ® 0% solids: 0 cc / min: 0 g / pr *

Claims (18)

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

1. A paper fabric having improved levels of tensile strength, tear strength and thickness, comprises: a wet creped paper tissue of density; densified regions distributed through tissue so that the distance between at least a part of the densified regions is less than or equal to the length of the longest fiber in the supply used to make the tissue paper.

2. The paper weave as claimed in clause 1, characterized in that the fines are concentrated in the densified regions.

3. The paper web as claimed in clause 1, characterized in that the aggregate supply chemicals are concentrated on a surface of the finished fabric.

4. The paper web as claimed in clause 1, characterized in that the chemical aggregates supply is caused to migrate and to concentrate therefore on a surface of the finished fabric in the densified regions

5. The paper fabric as claimed in clause 1, characterized in that the paper fabric is low density paper base fabric for towels and tissues

6. Paper weaving as claimed in clause 5, characterized in that the paper fabric is low density paper base fabric with improved tensile strength, tear resistance and improved thickness

7. A process for making a low-density wet creped pap that has improved levels of tensile strength, tear resistance and thickness, which comprises: remove a wet crepe paper from a Yankee dryer to a dryness between 45 and 65%; pressing the wet-creped paper web a subsequent dryer fabric to transfer the subsequent dryer fabric topography using a pressure point before the fabric is 60% dry; and keeping the weave of creped paper on the dryer fabric without any change in the coincidence in the wet creped fabric and the dryer fabric until the wet creped fabric is at least about 80%.

8. The process as claimed in clause 7, characterized in that the moist creped paper web is removed from a Yankee dryer at a dryness varying from about 50 to about 60%.

9. The process as claimed in clause 7, characterized in that the moist creped paper web is pressed into the dryer fabric then using pressure point to a fabric dryness ranging from about 50 to about 60%.

10. The process as claimed in clause 7, characterized in that the pressing step is logr using a hard press roll which is backed by soft roll so that the hard press roll h contacts the subsequent drying fabric and presses the cloth back dry on the base fabric which is backed or supported by the soft roller.

11. The process as claimed in clause 10, characterized in that the hard press roll is a steel roll and the soft roll is a rubber roll.

12. The process as claimed in clause 1, characterized in that the soft press roller h contacts the dryer fabric and presses the subsequent dry cloth into the base fabric which is backed or supported by a hard roller.

13. The process as claimed in clause 7, characterized in that the soft press roller h contacts the rear dryer fabric and presses the subsequent dry cloth into the base fabric which is supported by a dryer.

14. The process as claimed in clause 13, characterized in that the dryer canister is selected from a Yankee dryer, a heated drum, a vapor bottle, combinations thereof.

15. The process as claimed in clause 10, characterized in that the pressing step is carried out so that the load on the rollers is sufficient to produce a pressure at the clamping point of about 10 to about 400 pounds. per square inch

16. The process as claimed in clause 15, characterized in that the pressing step is carried out so that the load on the rollers is sufficient to produce a pressure at the clamping point of from about 15 to about 100 pounds per linear inch

17. The process as claimed in clause 15, characterized in that the pressing step is carried out so that the load on the rollers is sufficient to produce a pressure at the clamping point of from about 20 to about 50 pounds per linear inch.

18. The process as claimed in clause 7, characterized in that the moist creped paper web remains on the dryer fabric until it is about 95% dry. SUMMARY A wet creped paper web of b density having improved levels of tensile strength, tear resistance and thickness. The tissue has a distribution of densified regions corresponding to the distribution of the knuckles on a dried cloth. Generally speaking, these densified regions must be distributed so that the distance between at least part of the densified regions is less than or equal to the length of the fiber. longer in the supply (for example, pulp fibers and / or other fibers, used to make the tissue paper.) The wet-crepe paper is removed from the Yankee dryer to a dryness of between 45 and 65% and then passed to the back dryer section of a papier machine A back dryer fabric is pressed into the humid base fabric to transfer the topography of the fabric back dryer and to generate improved tensile strength, tear strength and thickness. Wet b-cloth is pressed into the dryer fabric using a pressure point before the fabric is 70% dry, once wet base fabric initially In contact with the dryer, it must remain on the dryer fabric without any change in the match between the wet base fabric and the dryer until the base fabric is at least about 80% dry.