DE2427291A1 - PROCESS FOR MANUFACTURING SOFT, THICK-HAND, ABSORBENT PAPER - Google Patents

Description

LAWYERS - .- -. _.

DR. JUR. OiPL-CHtM. WALTER BEIL fO. JUM 197 *

ALFRED;! ΟΞ: ^ Γ- ^ ί

DR. JUR. DIPL-C '-:? ..- »' .. H.-J. WOLFP

DR. JUR. HANS CHiv. iii.! L

FRANKFUSTAM MAIN-HIGHEST
ADEIONSTüaSSESB

Our number 19

The Procter & Gamble Company Cincinnati, Ohio, V.St.A.

Process for the production of soft, thick-grip, absorbent paper

The invention relates to improvements in paper and nonwoven manufacture and especially the production of a soft, thick-grip, absorbent, low-density paper, compared to papers produced according to known paper and fiber fleece production processes one considerably greater transverse stretchability, improved softness, improved Offers surface grip and improved drapability,

According to an important embodiment, the invention includes a polymer fiber monofilament-half-twill fabric, hereinafter also referred to for short as Prägegev / ebe or Köperqev / ebe, the

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when used for embossing a non-compacted paper web with certain fiber consistency values caused by thermal predrying, a dot-dash pattern generated in which the longitudinal axes of the line embossing parallel to the direction of paper travel, the longitudinal axes of the dot embossing lie at right angles to the direction of paper travel. This embossing fabric is particularly suitable for use in paper and fleece manufacturing processes, such as the method described in US Pat. No. 3,301,746, are suitable, the surface properties of the Fabrics are significant for the operation and the product properties.

In a preferred embodiment, the invention comprises a polymer fiber monofilament half-twill fabric of the type usually used for transporting wet paper webs through the web-forming, pressing and drying sections of paper machines, the twill fabric being shrunk by heat treatment after weaving, resulting in a dimensionally heat-stable fabric uniform hump heights and minimal "free" areas, ie in the interstices, on the side that comes into contact with the uncompacted paper web, the fabric being treated with a fine abrasive to enlarge its embossed hump surface by sanding off the surface that comes into contact with the paper web.

In Langsiebpapiermaschinen (Fourdrinier) Pa piermasse ^au f ^e i ⁿ a moving endless belt or wire applied, which is held by members of the machine rollers or driven and serves as the papermaking surface of the machine. These fourdrinier paper machine belts are usually formed from a piece of woven material, the Fourdrinier fabric, the ends of which are united in a seam to form an endless belt.

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Fourdrinier fabrics of this type generally have a plurality of spaced apart, longitudinally extending warp filaments and one A plurality of spaced, transverse weft filaments woven together on a corresponding loom are. For the purposes of this description, the warp filaments are of the fabric than that parallel to the paper or fleece running direction or machine direction in the continuous carrier tape Defined extending filaments, while the weft filaments, transverse to the machine direction or .machine direction lie.

Although the weave and fabric treatment criteria of the present invention also apply in other areas of use of polymer fiber monofilament fabrics, the features described here are most simply related with the use of such fabrics for embossing purposes in the. Paper web formation process understandable. In these procedures, For example, when operating a paper machine according to the information in US Pat. No. 3,301,746, improvements are made for the embossing fabric in relation to the transfer of the paper web (web transfer) and contact with the dryer surface is desirable. Besides that should be the embossing fabric used for the finished paper product only require the factors required by the paper manufacturer and corresponding to the target values of the product.

As polymer fiber monofilament fabrics are referred to here as the carrier for the moist paper web, which z. B. made of polyamide fibers, vinyl fibers, acrylic fibers and polyester fibers are woven as they are under the trade names or brand names Nylon, "Saran", "Orion", "Dacron" and "Trevira" are available. Although both the warp filaments and the weft filaments of such fabrics are made of multiple fibers The invention relates to warp and weft filaments made from monofilaments.

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Several different types of weave have been proposed for Fourdrinier fabrics but are currently being pointed out two types of weave are used, namely plain weave and half twill (semi-twill, long-crimp). With the plain weave each weft filament subsequently runs under a warp filament and then over the next warp filament, while in the half twill weave (in the following also simply as a twill weave each weft filament over two warp filaments, under the next warp filament and then over the next two warp filaments running in a repeating cough. Of these two types of weave, the half twill weave becomes most used.

The embossing fabric proposed in US Pat. No. 3,301,746 can rectangular or square or diagonally woven and any structures including, for example, canvas— or half twill weave. A according to US-PS 3 301,746 preferred embossing fabric has about 8-24 meshes / cm and is made of filaments with diameters of about 0.2-0.5 mm educated.

Paper made according to the information in US Pat. No. 3,301,746 using a half-twill embossing fabric made of polymer monofilament exhibits similar properties in most respects to paper made using of embossed fabric with plain weave is made of filaments of approximately the same diameter, if the half-twill fabric is installed so that its conventional "front" side is used for embossing the uncompressed paper web will. This is due to the fact that the conventional front side of half twill fabric (assuming that the fabric has uniform hump heights on its side touching the paper web) creates a dot-dash pattern in which the longitudinal axes of the line embossings are transverse

+) ("plain" weave)

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to the paper running direction, and the longitudinal axes of the dot embossing are parallel to the paper running direction. The line embossing result from every weft filament that is on the conventional fabric face in repetitive fluster under one warp filament and then over the next two Warp filaments run, while the dot embossing comes from each warp filament that is on the usual fabric front runs in a repeating pattern over one weft filament and then under the next two weft filaments.

If papers made with the usual face of a half twill weave are embossed according to the above information, are doctored off the drying drum, the dot-dash lines are Cusp embossing practically between the crepe folds. The resulting crepe folds therefore run practically without Interruptions across the width of the paper. The one with the conventional one Papers produced on the front side of a half-twill embossing fabric therefore show essentially similar properties, like the papers obtained on embossed fabric with plain weave, d. H. v / oak, thick-grip, absorbent papers lower Dense and with a characteristic crepe fold that extends essentially uninterrupted across the width of the paper -

On the other hand, using the "back" side gives one Half-twill fabric made of polymer monofilaments for embossing an uncompacted paper web according to the information in US Pat. No. 3-301,746 (on the assumption that the Gev / ebe on its side coming into contact with the paper web has uniform hump heights possesses) a dot-dash pattern in which the longitudinal axes of the line embossings are parallel to the direction of paper travel and the longitudinal axes of the dot embossing are transverse to the direction of paper travel. The line embossing is caused by each Kcttfilament, on the back of the fabric in a repeating pattern

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ster under one weft filament and then over the next two weft filaments runs while the dot embossing originate from each weft filament, which is on the reverse side of the fabric in a repeating pattern over a warp filament and then passes under the next two warp filaments.

The ones made with the back of a normal half twill fabric Papers embossed with polymer monofilaments show in contrast to either plain weave or conventional On the front of half-twill papers embossed a diamond-shaped fluster after creping.

It has been found that by increasing the embossed cusp area on the back of conventional half twill fabric Polymer monofilaments as specified in US Pat. No. 3,573,164 surprising improvements in the properties of the paper can be achieved. These surprising benefits include improvements the transverse stretchability, the softness, the grip quality (Surface grip) and drapability. The improvements take place with the enlargement of the embossing area on the back of the half-twill fabric too.

By grinding down the hump surfaces that come into contact with the paper web in accordance with the information in US Pat. No. 3,573,164 can be improved paper web transfer properties and improved drying of the paper web practically with all fabrics made of polymer monofilaments. The above improvements in terms of transverse stretchability, softness, The grip and drapability, on the other hand, can only be determined in connection with the back of half-twill embossed fabric according to achieve the above information.

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- * 7 -

It was found that in order to make the best possible use of the beneficial effects of abrading the cusp surfaces On the back of the embossed fabric, it is advisable to use half-twill fabrics that were made before the start of grinding have uniform cusp heights and minimal free areas on the reverse side of the fabric. Uniform hump heights enable a larger enlargement of the embossed cusp area and reduce the risk of it being completely sanded through of filaments. If the cusp heights are uniform before the start of the grinding process, the embossed pattern is also obtained more even after sanding.

Since fabric is the one described for embossing according to US Pat. No. 3,301,746 Species exposed to elevated temperatures during use it is advisable to heat-dimensionally stabilize the fabric before it is sanded down to enlarge its embossed cusp area to undergo. Failure to do so tends to weaken through careful weaving and before use subsequent sanding of the fabric side coming into contact with the paper web with treated uniform embossing surface increasing tissue temperatures for discard, eliminating most of the through such careful pretreatment obtained benefits are lost.

A method of making dimensionally thermally stabilized Fabric made of polymer monofilaments with glue-zandbond, the even cusp heights on both sides of the fabric and have minimal free areas is described in U.S. Patent 3,473,576. For this purpose, the fabric is made with a plain weave Polymer monofilament chain with relatively high heat shrinkability and certain initial distances between the warp monofilaments in the loom according to a mathematical, in US-PS 3 "473'576 given, equation, use of weft polymer monofilaments with relatively low heat shrinkability and usability

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ben with attachments to form a fabric with a plain weave produced an initial thickness calculated according to another mathematical equation given in the cited patent owns. After weaving, the fabric bumps on both sides of the fabric are then at even heights brought and the minimal free tissue surface is fixed by a heat shrink treatment, in which the tissue is attached to the Chain is kept under tension, but can shrink in the weft direction. The heat treatments are repeated, until the polymer monofilament fabric with plain weave no longer shrinks at the treatment temperature. In this condition it is considered "locked"; H. in the event of a later exposure to increased treatment temperature At the appropriate use temperature, there is no further shrinkage of the fabric.

It should be emphasized that the formation of even cusp heights and minimal free areas on both sides of the fabric in accordance with the weaving and heat treating processes disclosed in US Pat. No. 3,473,576 is based on the symmetry of the plain weave and does not lead to success with twill fabrics. Much more are used in the heat treatment according to the information in the just mentioned US-PS when using twill fabric made of polymer monofilament the cusps on the usual front side of the tissue are coplanar, before the cusps on the back of the tissue are uniform Have attained height. Therefore, in order to make the bumps on the back of the tissue coplanar, i. H. in the same plane To bring the fabric must be subjected to a further heat treatment. The ones to achieve even hump heights Additional heat treatment required on the reverse side of the tissue causes the cusp heights to be on the conventional The front of the fabric becomes uneven again.

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For twill fabrics made from polymer monofilaments, the initial warp filament spacing and the fabric thickness can be determined to achieve minimal free areas and even cusp heights on the back of the tissue after heat treatment are required, can only be determined experimentally.

The invention enables a calibratable, absorbent, low density creped paper that is on its surface has a diamond-shaped pattern and is related in terms of softness, surface feel and drapability, but also in relation on transverse stretchability is significantly improved.

Such a paper is, according to a preferred embodiment of the invention, in part in a manner known per se, e.g. B. as described in US Pat. No. 3,301,746, available when for embossing the uncompacted paper web prior to creping the back of a conventional half-twill fabric made of polymer monofilaments, which according to the details of US Pat. No. 3,573 abraded 'is used. According to a preferred embodiment, the non-compacted paper web is before the creping embossed in a dot-dash pattern, in which the longitudinal axes of the line embossings parallel to the Direction of paper travel, the longitudinal axes of the dot embossing across to the direction of paper travel.

The invention also provides semi-twill fabrics that are dimensionally stable made of polymer monofilaments for use as a carrier for fiber webs, for embossing and for other processing with the help of such fabrics are suitable and on the back uniform hump heights and minimal free areas have, which significantly helps to avoid transfer and contact problems in paper and nonwoven manufacturing processes contributes. The invention enables the production of thermally stable Half-twill fabrics of this type through solid

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Setting the criteria for achieving more evenly Cusp heights and minimal free areas on the reverse side of the fabric require weaving and heat treatment operations.

The invention offers such half-twill fabrics made of polyester monofilament for use in paper and fleece production, the reverse side of the fabric being measured in the cusp plane Total embossing area from about 20 to about 50% of the total tissue area and the embossed cusp area has a surface finish that is superior to its smoothness is at least equal to the surface finish, obtained by grinding with an abrasive, that is an effective abrasive grit size of less than about 50 tlikron (300 U.S. mesh).

The invention also provides a half-twill fabric made from polymer monofilament for the embossing and drying sections of paper machines, which are in contact with the moist paper web Coming back of the fabric to press the web against the surface of a dryer, an enlarged hump area has, which significantly increases the tensile strength of the dry paper product by avoiding Taserbindungsbruch contributes.

A preferred inventive soft, thick-grip, After creping, absorbent paper of low density shows a diamond-shaped pattern on its surface, occupied a transverse stretchability of about 2 to about 6% shows improvements regarding softness, surface feel as well as drapability and is especially used for

Fabrics «towel materials and suitable for hygienic purposes.

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According to a preferred embodiment, the soft, thick-grip, absorbent paper according to the invention can generally be produced in accordance with the information in US Pat. No. 3,310,746. In particular, an uncompacted paper web is formed for this purpose and supported or placed on the back of a half-twill embossing fabric with about $ -24 meshes / cm made of polymer monofilaments with diameters of about 0.2 to about 0.64 mm, the embossed cusp area on the back of the fabric, for example, according to the Information in US Pat. No. 3,573,164 is enlarged. The uncompacted paper web is brought to a fiber consistency of about 30 to about 98% by thermal pre-drying and a dot-shaped cusp pattern is embossed with the reverse side of the embossing web in such a way that the longitudinal axes of the line embossings of the pattern are parallel to the direction of the paper, the longitudinal axes of the embossing at right angles to the direction of the paper of the pre-dried, uncompacted one Paper web run. Finally the paper is dried and creped.

According to a preferred embodiment of the invention the back of the half-body embossed fabric made of rolymcrmonofilament according to the information in US Pat. No. 3,573,164 by grinding down the stool surfaces to enlarge the cusp level measured cusp embossing area to between about 20 and about 50% of the total tissue area and processed for polishing the cusp surfaces.

According to a further preferred embodiment of the invention If the half-twill fabric is woven from polmer monofilament and heat-stretched in such a way, then a dl men κ Lonr.iniinnicj warmth-stable Tissue is created that is uniform on its back before the cusp surfaces on the back of the tissue are abraded Has cusps and a minimal free area.

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The invention is explained with reference to the accompanying drawings. Show it:

1 shows the enlarged plan view of a conventional Rachtsgrat half-twill fabric made of polymerinonofilaments, made * see from the back, d. H. that side of the tissue that is normally in accordance with the state of the art does not come into contact with the paper web. The half-twill fabric made of polymer monofilaments is in his Initial state, d. H. before any sanding down and before use as an endless fabric tape shown for paper or fleece manufacture;

FIG. 2 shows an enlarged cross-section of the fabric shown in FIG. 1 according to 2-2 of FIG. 1 with a viewing direction across (CD) to the direction of paper travel, with the relatively higher position and the smooth hump surfaces the warp filaments are shown on both sides of the fabric;

FIG. 3 shows an enlarged cross section of the in FIG. 1 and FIG. 2 shown fabric according to 3-3 of FIG in the direction of paper travel (PiD), with the relatively lower position and the smooth hump surfaces of weft filaments are shown;

4 shows the simplified representation of an enlarged partial plan view of uncreped paper made using the normally used face of Half-body fabric of the type shown in Figures 1-3 is embossed. The longitudinal axes of the warp filaments generated dot embossings are parallel to. Paper direction;

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FIG. 5 shows the simplified representation of an enlarged partial top view of uncreped paper which, with the back of a fabric of the type shown in Figs. 1-3 is embossed. The longitudinal axes of the through the line embossings produced by the warp filaments lie parallel to the direction of paper travel;

6 shows the enlarged cross section of a fabric of the type shown in FIGS. 1-3, viewed transversely to Direction of paper travel at a point corresponding to section line 2-2 of FIG. 1 after the fabric one for the formation of even hump heights on the normally used front of the The fabric has been subjected to adequate heat treatment;

FIG. 7 shows an enlarged cross section of the one shown in FIG. 6 Fabric, seen in the direction of paper travel at one of the section line 3-3 in Fig. 1 corresponding Job;

8 shows the simplified representation of an enlarged partial top view of uncreped paper which is produced with the. Usually used front side of half-twill fabric made of polymer monofilaments of the type shown in FIG. 6 and 7 shown type is embossed. The longitudinal axes of the line embossments produced by the weft filaments are transverse to the direction of paper travel, the longitudinal axes of the " Dot embossing parallel to the direction of paper travel;

9 shows the simplified representation of an enlarged Partial plan view of uncreped paper bonded to the back of a half-twill fabric of the type shown in FIGS

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and 7 shown type is embossed. The longitudinal axes of the line embossments produced by the warp filaments lie parallel to the direction of paper travel;

Figure 10 is an enlarged cross-section of a fabric of the type shown in Figures 1-3 and 6-7 transversely to the direction of paper travel at a point corresponding to section line 2-2 of FIG. 1 for the formation of even cusp heights and the smallest possible free areas on the back of the tissue adequate heat treatment of the fabric. It can be seen that the hump heights are no longer uniform on the front side of the fabric that is usually used;

FIG. 11 shows an enlarged cross section of the one shown in FIG. 10 Fabric, seen in the direction of paper travel at one of the section line 3-3 of FIG. 1 corresponding Job;

FIG. 12 shows the simplified representation of an enlarged partial top view of uncreped paper which is accompanied by the commonly used front side of half-twill fabric of the type shown in FIGS. 10 and 11 is embossed is. The longitudinal axes of the line embossments produced by the weft filaments are transverse to the Paper direction;

13 shows the simplified representation of an enlarged partial top view of uncreped paper which is also covered with the back of a fabric of the type shown in Figs. 10 and 11 is embossed. The longitudinal axes of the line embossings produced by the warp filaments are parallel to the direction of paper travel Longitudinal axes of the filaments produced by the weft

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Dot embossing across the direction of paper travel. the Dot embossing is here because the stool is even on the back of the fabric are high;

Fig. 14 is an enlarged cross-section of a fabric of the type shown in Figs. 10 and 11, seen transversely to the direction of travel of the paper at a point corresponding to section line 2-2 in FIG the back of the tissue to enlarge its embossed cusp area has been abraded;

15 shows an enlarged cross-section of the fabric shown in FIG. 14, seen in the direction of paper travel at a location corresponding to section line 3-3 of FIG. 1;

FIG. 16 shows the enlarged partial plan view of the FIG. 14 and 15, viewed from the reverse side of the fabric;

17 shows the photographic representation of the top view in FIG Enlarged about twelve times on uncreped paper with the reverse side of a fabric of the is embossed in the type shown in Figs. 14-16. The resulting pattern is similar to Fig. 13, but the dot-dash embossings form a larger percentage of the paper surface, v / eil the embossed cusp area of the tissue is enlarged;

18 shows an enlarged cross-section of the uncreped paper shown in FIG. 17 transversely to the paper running direction after 18-18 of Fig. 17;

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19 shows the photographic representation of a plan view, enlarged approximately six times, of a paper of the FIGS 17 and 18 shown type after creping. The longitudinal axes of those visible after creping Embossings are generally oriented transversely to the direction of paper travel, while the entire surface of the Paper has a rhombus-shaped or diamond-shaped cough, as is the case for papers produced according to the invention is characteristic;

FIG. 20 shows an enlarged cross-section of the creped paper from FIG. 19 transversely to the paper running direction 20-20 of Fig. 19.

To explain preferred embodiments of the invention For the sake of clarity, reference is made to the characteristics of the fabric used in the manufacture of paper and nonwovens special terminology is used for polymer monofilaments. The conventional "front" side of the one mentioned here Half-twill fabric is that side of the fabric which, according to the state of the art, is normally in contact with the paper web Contact would come, d. H. that side of the half-body fabric which, depending on its particular condition, is one of the in the Fig. 4, 8 or 12 would form the embossing pattern shown (assuming that it is a right burr twill fabric acts). In the figures just mentioned, the longitudinal axes of the line embossings 9 that may be present lie transversely to the paper running direction, while the longitudinal axes of the possibly existing dot embossing 3 parallel to the paper running direction are oriented. The "back" side of the half twill fabric discussed here is defined as the side which according to the prior art would normally not come into contact with the paper web, d. H. that side of the Half-twill fabric, depending on their particular condition one

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the embossing pattern shown in FIGS. 5, 9, 13 or 17 would produce (assuming that it is a right ridge body tissue). In the last mentioned figures are the longitudinal axes of the line embossings 8 parallel to the direction of paper travel, the longitudinal axes of the possibly existing dot embossing 10 transversely to the direction of paper travel.

Although throughout the present description on right ridge half-twill fabric As reference is made, the advantages described can also be achieved with left-hand half twill fabrics woven as mirror images of right ridge half-twill fabric.

1 shows the enlarged plan view of part of the rear side of a conventional right-ridge-IIalbköporgewobor; made of polymer monofilament. The fabric shown in FIG. 1 has not yet been used on the paper machine and has not been subjected to any special grinding treatment. The warp monofilaments 1 are parallel to the machine direction (MD), that is to say parallel to the paper running direction, the weft monofilaments 2 are perpendicular to the machine or paper running direction. In a preferred embodiment of the invention, the embossing fabric shown in FIG. 1 has about 8 to about 24 stitches per cm (corresponding to about 20 to about 60 stitches per inch) and is made of Plonof ilnment-polymer fibers with diameters of about 0 .2 to about 0.65 mm (about 0.003 to about 0.025 inches). The monofilaments of the warp and weft can have the same diameter, but this is not necessary. FIGS. 3 and 2 show cross sections of the fabric shown in FIG. 1, viewed in the direction of paper travel or transversely thereto. The stools formed at the crossing points of the warp filaments 1 and the weft filaments 2 are neither on the front nor on the back of the fabric in the same plane. As can be seen from FIGS. 2 and 3, the warp filaments 1 are located on both sides of the fabric.

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tively higher than the weft filaments 2. This is called "high-chain" State of the tissue.

Fig. 4 shows a simplified representation of the embossed cusp pattern, that would arise if a fabric of the type shown in Figs. 1-3 is built into the paper machine in this way, that the conventional fabric front is used for embossing an uncreped paper web, as it is according to the information U.S. Patent 3,301,746 is obtained. The dot embossing visible on the surface of such a paper after embossing 3 form a pattern corresponding to the humps 4 of the warp filaments 1 on the conventional fabric front side. Since the point embossments 3 are formed by the warp filaments 1, the longer ones referred to here as the longitudinal axes lie Axes of the dot embossing parallel to the direction of the paper flow or riaschxnenrichtung (MD). The from the weft filaments 2 on The bumps 7 formed on the conventional fabric front side do not form any corresponding bumps in the non-compacted paper web Embossing because they are relatively lower than the warp filament humps 4.

FIG. 5 shows the embossed cusp pattern which would result if one were not produced in accordance with the details of US Pat. No. 3,301,746 compacted paper web with the back of an embossing fabric of the type shown in Figs. 1-3 would be embossed. Since the Warp filaments 1 on the back of the fabric are relatively higher than the weft filaments 2, are only used during embossing the tips of the stool 5 formed by the warp filaments are embossed into the paper web. Since the warp filaments 1 in the paper running direction run, the resulting pattern consists of rows of relatively long line embossings 8, their longitudinal axes parallel to the direction of paper travel.

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The embossing pattern shown in FIG. 5 differs from the embossing pattern shown in FIG. 4 in two essential ways Points of view. First of all, the length of the embossing is almost twice as long when the paper web is with the fabric reverse side is embossed because on the back of the twill fabric each warp filament 1 over two weft filaments 2 on the front of the fabric but only runs over one weft filament. Besides that when removing a paper web embossed with the cough shown in FIG. 5 with the usual scraper from the drying drum on the paper surface has a diamond shape Pattern generated while removing a paper web embossed with the pattern shown in FIG. 4 with the usual Scraper from the drying drum creates a regulated crepe pattern in which the crepe folds are practically unbroken run across the width of the web. This characteristic difference in finished products is apparently due to this implies that the web shown in FIG. 4 adheres to the drying drum only at interrupted intervals, i. H. via the dot embossments 3, which are not so long that they overlap one another in the direction of paper travel. In contrast to this the paper web shown in Fig. 5 adheres continuously to the drying drum, namely with the line embossing 8, which are so long that they overlap each other in the direction of paper travel.

On the basis of the prior art and in particular US Pat. No. 3,473,576, it results that smooth paper web transfers (Transfer) and maximum drying efficiency cannot be achieved with fabrics that have rough or irregular web contact surfaces to have. Smooth paper web transfers are particularly important when, as in the case of that disclosed in U.S. Patent 3,301,746 Papermaking process the embossing fabric is important for the product properties. Therefore, such embossing fabrics have become proved to be expedient, the on the with the un-

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sealed paper web in contact with the fabric side evenly Cusp heights and the smallest possible free areas, d. H. have no spaces between them. Because such embossing fabric at If their use are exposed to higher temperatures, it has proven to be useful to clean the fabric before use dimensional stabilization by means of heat treatment to prevent warping or warping of the tissue (here also as "Thermal dimensional stabilization").

It is important to note that the heat treatment of the type described in US ^{Pat. No. 3:} 473 576 achieves uniform hump heights and minimal free areas on both sides of the fabric at the same time because of the symmetry of fabrics with a plain weave. This is the case with fabrics with twill or Half twill not the case. If a semi-twill fabric of Polymermonofilament a heat treatment according to the US-PS is subjected to 3 '473 ¹ 576, the stool 4 and 7 are on. the conventional front side of the tissue is brought to the same level before this is done with the cusps 5 and 6 on the rear side of the tissue. So that the stools 5 and 6 achieve the same heights on the back of the fabric, the fabric must be subjected to a further heat treatment. The additional heat treatment causes the heights of the stools 4 and 7 on the conventional front side of the half-body fabric to become uneven again.

Accordingly, the original warp filament spacings and the thicknesses are used to form the smallest possible open spaces and even cusp heights on the back of the fabric after the heat treatment required half-body fabrics experimentally to determine.

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According to a preferred embodiment of the invention the half-twill fabric made of polymer monofilaments with warp monofilaments which have a relatively high heat shrinkability in the range of about 10 to about 30%, preferably about 16%. After selecting and spacing the monofilaments The warp is made of polymer monofilaments for the weft with a relatively low heat shrinkability in the range of about 2 to about 8%, preferably about 4%. During the heat shrinkage treatment, the mentioned shrinkage properties of the monofilaments of the warp and weft advantageously used v / ground. In the heat shrinkage treatment, the original fabric is stretched State and in the longitudinal (warp) direction fixed state subjected to a series of heat treatments, the fabric in Weft direction can shrink freely.

The untreated ileal body tissue is expediently as endless belt, on a production table which is usually used for finishing paper machine fourdrinier wires made of metal wire type used attached ^ subjected to heat shrinkage treatment. A common wire screen manufacturing table consists of two adjustable rollers that carry, tension and move the wire screen or fabric closed to form an endless belt. The heat shrinkage can expediently with the help of infrared radiators causes v / earths, which are attached as batteries across the raw fabric. The infrared emitters are the corresponding areas of the raw fabric moving slowly around the rollers of the production table are heated. The heat is in consecutive treatments of about 5 to about 40 seconds, preferably about 15 seconds, per treatment on the tissue Brought action. The tissue temperatures slowly approach this during the successive heat exposure Softening point of the polymer monofilaments used. To a sudden shrinkage that causes tissue to fold

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avoid, work is carried out in several passes. The successive heat treatments are repeated until the heights of the cusps on the back of the fabric have become even, this state should also correspond to the smallest free area or gap area, if the original warp filament spacing and the original fabric thickness have been determined accordingly. An abandoned the above-mentioned heat treatment method semi twill fabric is not "blocked" as one such heat treatments, exposed plain weave fabric, but at the temperatures as in the US-PS ^3'3Ül: occur '74b described paper web embossing process, dimensionally heat stable.

The temperature of the monofilaments in the successive heat treatment steps is increased up to a maximum temperature which is immediately below the softening point of the selected fibers or monofilaments. For example, the heat treatment temperature for "Trevira" fibers is about 182 ° to about 204 ° C., preferably about 190 ° C. For thermal dimensional stability for use as an embossing fabric in accordance with the information in US Pat. No. 3 ^: 301 "746, a sufficient number of successive heat treatments is required provided to ensure that the polymer monofilaments of the fabric structure have been held at the highest heat treatment temperature for a total of about 15 to about 120 seconds.

Contrary to expectations, a weaving process results in which the warp and weft made of polymer monofilaments are only as dense as possible to achieve a minimal free area, not to a fabric that is woven after heat treatment or when used an even hump height in dry sections of the paper web having. Polymer fibers are generally subject to heat

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shrinkage, and trying a dense weave with minimal initial spacing of both the Kott and the weft threads made of polymer monofilaments results after heat treatment and heat stabilization a tissue with uneven cusp heights. Accordingly, according to a preferred one Embodiment of the invention the initial warp filament spacing in the loom and the initial thickness of the half-twill fabric experimentally to account for heat shrinkage determined in the thermal dimension stabilization process described above.

FIGS. 6 and 7 show enlarged cross-sections of a half-twill fabric of polymer monofilaments of the type described in FIGS. 1-3 after the start of the heat treatment process described above . The cross-section of FIG. 6 is transverse to the direction of paper travel at a point corresponding to the cutting line 2-2 of Fig. 1, while the cross-section of Fig. 7 in the direction of paper travel at a point corresponding to the Section line 3-3 of FIG. 1 is seen. FIGS. 6 and 7 illustrate an intermediate state of the tissue which is produced during the Heat treatment process before achieving uniform cusp heights and the smallest open spaces on the reverse side of the fabric is achieved. Fig. 6 shows the state which results when the warp filaments 1 are straightened due to the heat shrinkage kick off. The tendency of the warp filaments 1, as a result the heat shrinkage to assume a lower overall amplitude, forces the weft monofilaments 2 on the conventional Fabric front side down and the weft monofilaments 2 on the fabric back side up, because the ends of the weft monofilaments are not fixed. In Fig. 7 it can be seen more clearly how the weft monofilaments 2 to a complete wrap of the warp monofilaments 1 tend. As a result, the weft monofilaments come on the conventional front side of the fabric 2 formed stools 7 in the same level (copla-

409881/0945

nar) like the stool formed by the warp monofilaments 1 4. It should be noted that the warp monofilaments on the stool 5 formed on the backside in this special stage are relatively higher than those of the weft monofilaments 2 formed stool 6.

FIG. 8 shows a simplified representation of an enlarged partial plan view of uncreped paper which, according to US Pat 3-301 746 manufactured and with the conventional front side of a half-twill fabric made of polymer monofilaments in the Fig. 6 and 7 shown type is embossed. The cusp embossing pattern is similar to that of Fig. 4, in much the same way that of the cusps 4 of the warp monofilaments 1 formed on the front of the fabric Point embossings 3 are explained, but also contains the line embossings formed by the cusps 7 of the weft monofilament 9. Since the weft monofilaments 2 transverse to the direction of paper travel lie, the longitudinal axes of the line embossings 9 are also oriented transversely to the direction of paper travel.

9 shows a simplified representation of an enlarged partial plan view of uncreped paper which, according to US Pat 3 301 "74G and with the back of a half-bodied fabric of the type shown in Figs. 6 and 7 is embossed. As in Fig. 5, the longitudinal axes of the humps 5 of the Warp monofilaments 1 formed line embossings 8 oriented parallel to the direction of paper travel.

As with paper embossed with the pattern shown in FIG. 4, paper embossed with the pattern shown in FIG. 8 shows is characterized, a fundamental regularity of the creping, at v / elcher the crepe edges extend practically uninterrupted over the entire width of the paper web. By adding of the line embossing 9 for the embossing pattern, the fact remains unchanged that the embossed paper is only used in interrupted

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tervallen adheres to the drying drum in accordance with the distances between the dot embossings 3 in the direction of paper travel. on the other hand show papers embossed with the pattern shown in FIG are, a diamond-shaped fluster that is used for according to the invention Process produced paper after doctoring from the drying drum is characteristic.

To achieve even hump heights and the smallest open spaces on the back of half-twill fabric of the type shown in Fig. 6 and 7, as is desired for a preferred embodiment of the invention, the heat treatment is so continued for a long time until one of the illustration in FIGS 11 a similar state is achieved. FIG. 10 is transverse to the direction of paper travel at a section line 2-2 of FIG. 1 corresponding Seen place, while FIG. 11 in the direction of paper travel at one of the section line 3-3 of FIG Place is seen. As shown in Fig. 10, the heat shrinkage of the warp monofilaments has a decrease in the overall amplitude generated, whereby the weft monofilaments 2 move upwards on the reverse side of the fabric, the weft monofilaments 2 Move down on the conventional front side of the fabric. As can be seen in FIG. 11, the weft monofilaments are grounded 2, which unlike the warp monofilaments 1 no tension tend to wrap more completely around the warp monofilaments / those on the conventional fabric face lie. At the same time, the weft monofilaments 2 tend to move increasingly around the two adjacent warp monofilaments Wrap ilamente 1 on the reverse side of the fabric. As a result, the heights of the warp monofilament humps 5 on the back of the fabric are grounded and the weft monofilament humps 6 on the back of the fabric evenly, while the heights of the weft monofilament humps 7 on the conventional front of the fabric and the warp monofilament stool 4 on the conventional front of the fabric become uneven. If the original

409881/0945

Warp filament spacing on the loom and the initial thickness of the half-body fabric accordingly to take into account the heat shrinkage have been determined, the one shown in Figs. 10 and

11 can be reached, d. H. a "V / area dimension stabilized Half-twill fabric with a uniform cusp height on the reverse side and the smallest open space are created.

12 shows the simplified representation of an enlarged Partial plan view of uncreped paper produced in accordance with US Pat. No. 3,301,746 and with the conventional front side has been embossed by Halbköpergev / ebe of the type shown in Figs. The embossing pattern is basically similar 8, but those of the warp monofilament bumps are absent 4 point embossings 3 formed by the conventional fabric front soap, v / eil the warp monofilament humps 4 on the conventional fabric front side, relatively lower than the weft monofilament humps 7 are. One with the one shown in Fig.

After creping, the pattern of embossed paper shown in FIG. 12 shows essentially similar properties to those with the whispered embossed paper shown in Figs.

13 shows the simplified representation of an enlarged partial plan view of uncreped paper which, according to US Pat 3'301 * 746 made and with the back of half twill fabric, of the type shown in Figs. 10 and 11 is embossed. Those formed by the warp filament humps 5 on the back of the fabric Line embossings 8 are shown essentially the same as in FIG. 8, but are also those of the weft filament bumps 6 dot embossings 10 formed on the back of the fabric because the warp filament humps 5 and the weft fi lament humps 6 have uniform heights on the back of the fabric. One with the back of half twill fabric of the Fig. 10 and 11 shown type embossed paper shows after

40 9881/0945

Creping is a characteristic of papers produced according to the invention diamond-shaped surface appearance. When enlarging the embossed cusp area on the back of such Half-body fabric made of polymer monofilaments becomes the diamond-shaped one Pattern more pronounced.

It was found that the enlargement of the embossed cusp area on the reverse side of such a fabric also certain surprising improvements in the properties of the finished product Paper offers, in terms of improved transverse stretchability, improved softness, improved hand and improved Draping properties. The enlargement of the embossed cusp area on the conventional face of a similar one Half-body embossed fabric made from polymer monofilaments, on the other hand, does not provide any similar improvements in the properties of the finished material. This also applies to embossed fabrics with plain weave. In this way the surprising insight emerged obtained that the above described improvements in paper characteristics only by enlarging the embossed cusp area on the back of conventional half-twill embossing fabrics can be obtained from polymer monofilaments.

A method for increasing the embossed cusp area of polymer monofilament fabric is described in US-PS 3,573,164, according to which the hump surfaces to improve web transfer, Web drying, web product properties and general plant operation can be sanded down with a fine abrasive. According to a preferred embodiment of the present invention the semi-twill embossing fabric made of polymer monofilaments to be abraded on the back is already in brought the state shown in Figs. 10 and 11, i. H. Formation of uniform heights of ilock and slightest l-'rcifL'icho on the back side. Although the abrasive treatment described in the aforesaid U.S. patent was initially performed on a fabric

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2427231

uneven cusp heights an even cusp height results is according to a preferred embodiment of the invention It is advisable to use fabric that is even at the beginning on the surface to be treated Ilöckerhöhen has the possibility of a complete looping through to minimize one or more monofilaments when grinding. Therefore, the back of a fabric can of the type shown in FIGS. 10 and 11 are ground off more strongly and thereby a greater increase in size the cusp embossing surface than this with a tissue is the case that initially has uneven cusp heights on the side to be treated.

As already mentioned above, it has proven to be useful the polymer monofilament fabrics are thermally dimensionally stable before use close. If this does not happen, the level can increase after commissioning and action Discard temperatures. Therefore, in order to obtain the full benefits of abrading, it is in accordance with a preferred embodiment of the invention particularly expedient, the half-twill fabric before the start of the abrasion treatment according to the to subject the methods described here to thermal stabilization.

According to a preferred embodiment of the invention the back of a half-copier embossed fabric made of polymer monofilaments one z. B. from US-PS 3-573 164 known per se Subjected to treatment, at v / elcher, the stool surfaces of the fabric either using wet or dry Sandpaper with an effective abrasive grain size of about 30-50 microns (equivalent to about 300 to about 500 U.S. mesh) be abraded as an abrasive. The abrasive can for the rotating treatment of the cusp surfaces of the tissue

409881/0945

Drums may be provided. The sanding can take place at the same time Spraying the fabric with water or another cleaning or lubricating liquid, for example light oil, to remove abraded particles and to facilitate polishing.

According to a preferred embodiment of the invention on the treated surface a total embossed cusp area of about 20 to about 50% of that measured in the cusp plane Total tissue area developed. By enlarging the embossing area to over 50%, the risk of individual monofilaments being completely looped through is greatly increased and moreover an adverse effect on the useful life of the fabric is likely.

According to a further preferred embodiment of the invention it is advisable to use a smooth and smooth surface on the back of the half-twill fabric made of polymer monofilaments to form polished surface. To this end, the grinding described above can be carried out in various stages. For example, the initial grinding can be done with an abrasive that has an effective abrasive grain size of about 50 microns (about 300 U.S. mesh), followed by an abrasive polishing treatment using water lubricated wet sandpaper, which is an effective abrasive grain size of about 30 microns (about 500 U.S. mesh). Polishing abrasives, such as talc, polishing red or polishing cloth, can also be used to further polish the cusp surfaces.

409881/094

14 and 15 show enlarged cross-sections of half-twill fabric made of polymer monofilaments of the type shown in FIGS. 10 and 11 after the reverse side of the fabric has been ground off has been made to measure the embossed cusp area to between about 20% and about 50% of the total tissue area, measured in the Level the stool to enlarge. FIG. 16 shows the enlarged plan view of a part of that shown in FIGS. 14 and 15 Of fabric, seen from the back of the fabric. This in 14-16 illustrated fabric represents a preferred embodiment of the invention, in which prior to the beginning of the Abrasive process on the reverse side of the fabric, uniform cusp heights and the smallest open area were created. A coherent with the formation of even cusp heights and the smallest free area before starting the sanding process The advantage is the uniformity of the embossed cusp pattern obtained after grinding. This latter property can best be seen in FIG.

14 and 15 show the fabric profile viewed transversely to the paper running direction or in the paper running direction, which is a Uncompressed paper web presents when the fabric is used for embossing in accordance with the information in US Pat. No. 3,310,746 will. The warp filament bumps 5 and the weft filament bumps 6 as shown in FIGS. 10 and 11 are as shown 14 and 15 to plateau-shaped warp filament humps 5 'or weft filament bumps 6' ground off. Additionally To improve web transfer and web drying properties, the plateau-shaped cusp areas are characteristic 5 'and 6' an uncompacted paper web in more uniform Depth with a clearer embossed pattern.

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The one carried by an embossing fabric according to the invention The moist paper web can be thermally produced by passing hot cases, for example air, through the moist paper web and the embossing fabric is pre-dried. A suitable device for pre-drying the moist paper web is in U.S. Patent 3,303,576. Although the means used to achieve thermal predrying are not critical it is critical that the relationship between the moist paper web and the embossing fabric that has once been achieved is maintained will.

According to US Pat. No. 3,301,746, thermal pre-drying is used to bring about a fiber consistency of the moist paper web of about 30 to about 80%, preferably about 40 to about 80%. that with fiber consistency values below about 30 %, the desired balance of properties of the paper obtained in terms of softness, thickness and absorbency suffers, because the web and its fibers are too moist and the web yields or gives way during embossing cited US patent is also stated that the predrying to fiber consistency values of over about 80% excludes the development of effective tensile strength values of the embossed paper.

It is known that pasting consistency values between approximately 3 ° and approximately 98 % are possible before the transfer of the paper web to the drying drum without adversely affecting the tensile strength of the paper produced in this way 3ol 746; those above about 80 % are obtained by spraying an aqueous solution of polyvinyl alcohol adhesive on the surface

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achieved by the drying drum prior to web transfer. The said Adhesive is characterized by a degree of hydrolysis of about 80 to about 9 0% and a viscosity (as a 4% aqueous solution at 20 C) of greater than about 20 centipoise. Per ton of paper produced (dry weight) about 0.25 to about 1 kg of polyvinyl alcohol (dry weight) are applied.

The embossing of the fabric tubercle pattern into the moist web by pressing the pre-dried one that is still supported by the embossing fabric Web against a relatively non-yielding surface, such as an unheated steel roller, or the surface of a Self-acceptance dryer (Yankee dryer) gives a paper in the surface of which to a depth of at least 30% of the machine-smooth thickness of this paper, the hump pattern of the embossing fabric is embossed. The machine-smooth thickness refers to on the thickness of the direct from the self-acceptance dryer removed paper before creping. Accordingly, the hump surfaces 5 'and 6' as shown in FIGS 14-16 of a preferred embodiment of the invention to a uniform depth of at least 30% of the machine-smooth Embossed thickness of uncreped paper.

The pressure required for embossing the embossing fabric pattern can according to a preferred embodiment of the invention are generated by a pressure roller or several pressure rollers that act on the embossing fabric, so that the stool of the Fabric pressed into the surface of the pre-dried paper web and pressing the surface of the pre-dried paper web under the humps against a self-acceptance dryer surface will.

409881/0945

For the implementation of the invention it is important that the embossing process described above is the first, practically in its entirety v / acting mechanical compaction to which the paper web is exposed during web formation and predrying.

17 shows an enlarged photograph of a partial top view of an uncreped paper produced according to the specifications of US Pat. No. 3,310,746 using the reverse side of a half-twill fabric of the type shown in FIGS. 14-16 for embossing the uncompressed paper web. The resulting cusp oyster is essentially similar to the pattern shown in FIG. However, the line embossings 8 formed by the warp filament humps 5 'and the dot embossings 10 formed by the weft filament humps 6' form a larger percentage of the paper surface because the size of the fabric humps is increased. In addition, the embossments 8 and 10 are clearer because they are formed with a practically uniform depth by the plateau-shaped surfaces of the cusps 5 ¹ and 6 '.

FIG. 18 shows an enlarged cross-section of the uncreped paper from FIG. 17 to 18-18 transversely to the paper running direction.

19 is an enlarged photographic representation of a partial plan view of a according to the information of US Pat. No. 3,301,746 produced creped paper, but using dor Back of a half-twill fabric according to FIGS. 14-16 for embossing the uncompacted paper web before creping. the The longitudinal axis of the embossings 11 visible after creping appears generally to be oriented transversely to the direction of paper travel. in the This differs from that produced according to the information in the US Pat Paper when using either one of the similar

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Way manufactured embossing fabric with plain weave or the usual front side of a manufactured in a similar way Half-twill embossing fabric shows the entire surface of the paper a diamond-shaped pattern and not a uniform unbroken pattern Crepe edges that extend across the width of the paper.

FIG. 20 shows an enlarged cross section of the paper from FIG. 19 transversely to the paper running direction according to 20-20 in FIG. 19th

A finished paper produced according to the invention according to 19 and 20 shows improvements in relation to transverse stretchability, Softness, surface feel and drape properties, as they are not obtainable by the process described in US Pat. No. 3,301,746 when embossing a uncompacted paper web before creping a similarly produced fabric with plain weave or the conventional one Front side of a half-twill fabric made in a similar manner can be used. The enlargement of the Ilöcker embossing surface on a fabric with a plain weave or on the conventional front side of half twill fabric improves the paper web transfer and the paper web drying properties, but does not produce the improvements in transverse stretchability, softness, surface feel and draping properties, as they are when the cusp embossing area is enlarged can be realized on the back of a half-body embossed fabric.

From the above general and specific description of the present process it follows that the invention itessential procedural steps the formation of an uncompacted Paper web with a fiber consistency in a certain area and the embossing of this web by the stool

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on the back of a half-body embossing made of polymer monofilament are, wherein the fabric has a cusp embossing surface has, which on the back of the tissue about 20 to about 50% of the total area measured in the cusp plane matters. The formation of the paper web and the final drying technique as well as the pre-drying, embossing and Creping methods can be used by those skilled in the art to produce different papers for different uses in the frame the inventive method can be modified.

The above procedures produce creped paper that has a diamond-shaped surface appearance, consists essentially of cellulose fibers, a surface

2
weight from about 8 to about 6 5 g / m (about 5 to about 40 pounds /

3000 feet) and a repetitive pattern of individual ones Has embossed areas.

To the improved properties of the according to the invention Processes to show manufactured finished products were series of tests to compare the properties of papers carried out according to the information in US-PS-3,301 * 746 under Using the different sides of a half-twill fabric made from polymer monofilaments. the With the exception of the embossing fabric, the working conditions of the paper machine were kept constant in all test series.

One entry was used for all test series, the 50 'έ Softwood sulfate pulp (Kraft pulp) and 50% hardwood sulfite pulp contained.

A layer of glue was applied to the self-acceptance dryer surface applied with a glue roll of approximately 16 nitches / cm (about 40 U.S.-mesh) which is arranged with a Circumferential longitudinal speed of about 2.7 m / min, in one

409881/0945

into the open glue container and the one from the glue roller picked up glue with a series of air nozzles arranged inside the glue roll, which continuously

borrowed were fed with compressed air of 6 ₃ 3 kg / cm, sprayed onto the surface of the self-acceptance drying drum. The glue used came from the Peter Cooper Corporation, Gowanda, New York, and had the type designation "Peter Cooper IX". The applied mixture contained 1 part glue and 99 parts water. The pre-dried and embossed paper web was separated from the embossing fabric by means of the glue layer described above at the pressure nip exit and made to adhere to the self-acceptance dryer surface.

The dry creped paper was removed from the self-acceptance dryer with a conventional scraper, making the finished Product exhibited 12% crepe fold stretchability.

For the tests, two different half-body sizes were chosen Polymer monofilaments used. Both fabrics were in the direction of paper travel 12 nibbles / cm (31 U.S.-mesh), 11 stitches / cm (28 U.S.-mesh) crosswise to the machine direction. Warp and weft monofilaments were 0.4-5 mm in diameter. One of the Fabric was woven in such a way that its reverse side presented itself as the surface in contact with the paper web, while the other fabric was woven so that the conventional face was the surface in contact with the paper web was. Both fabrics, when obtained, had a shape corresponding to that shown in Figures 10 and 11, i. the heights of the warp filament humps 5 and the weft filament humps 6 were approximately the same on the back of each fabric, while the warp filament humps 4 on the conventional front of each tissue were lower than the weft filament humps 7.

409881/0945

To isolate the effects of the embossing fabrics on the properties of the finished papers, the fabrics were sequenced Mounted in the received condition on the same paper machine and thus produced paper according to US Pat. No. 3,301 "746.

The fabric that was woven in such a way that its reverse side is the surface that comes into contact with the paper web darbot, showed an initial cusp embossing area in the delivered condition of about 21.2%, while the fabric which was woven so that its conventional face than with the area coming into contact with the paper web was present in the delivered Condition showed a cusp area of about 23.4%.

In Example I below, values of paper samples are compiled that were obtained using the embossing fabric with the back in contact with the non-glued paper web. In Example II the values are compiled from paper samples that are in contact with the conventional face using the embossing fabric were made with the non-glued paper web. With the exception of the embossing fabric, the operating conditions were the Paper machine unchanged for Examples I and II.

To explain the effect of enlarging the embossed cusp area on the side of the embossing fabric that comes into contact with the paper web, each fabric was placed according to the specifications of US-PS 3573 164 abraded. The cusp embossing area on the fabric, the back of which is in contact with the paper web area served was increased from about 21.2% to about 28.4%. The embossed cusp of the tissue whose The conventional face used as the area in contact with the paper web was reduced by approximately 23.4% enlarged by approximately 34.1%. The tests were repeated where-

409 881/0945

in all conditions of the paper machine apart from the enlarged one The embossed cusps on the tissues remained unchanged. The test results from paper samples of each run are given below as Examples III and IV. The values compiled in Example III come from paper samples which were obtained using the half-twill embossing fabric / the reverse side of which was facing the uncompacted paper web. The values compiled in Example IV are from samples obtained using the half-twill fabric whose conventional front face was facing the uncompacted paper web.

Finally, the bumps embossed surface was further increased each fabric according to the information in US-PS 3 ^r 573 164, until the fabric of which back surface was used as with the paper web coming into contact surface, having a total bumps embossing area of 37.3%, while the fabric whose conventional front side served as the area in contact with the web, had achieved a total embossed cusp area of 40.4%. The tests were repeated using all paper machine conditions _; apart from the embossed cusps of the tissues ^ remained unchanged. The results of the tests performed on paper samples from each run are presented in Examples V and VI below. The values of Example V come from paper that was obtained using half-twill fabric, the reverse side of which was facing the uncompacted paper web. The values compiled in Example VI come from paper samples obtained using half-twill fabric with the conventional front side facing the uncompacted paper web.

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The paper thickness given in the following examples is in each case the one below
measured thickness in mm.

2 2

each under a pressure of about 12.4 g / cm (80 g / inch)

The tensile strength values given in the examples in the direction of paper travel (MD) and transverse to the direction of paper travel (CD) are reported as the force in grams of a 2.54 cm wide sample with a 10.2 cm gap between the clamps the tensile strength testing system, cut in the direction of HD or CD, can withstand tearing. A standard “Thwing-Albert Tensile Tester "from Thwing-Albert Instrument Company, Philadelphia, USA.

The percentage stretchability values in the following examples were determined in connection with the measurement of the tensile strength values determined in the MD and CD directions.

A measuring device with the designation "Thwing-Albert Handle-O-Meter", Catalog No. 211-3 of the Thwing-Älbert Instrument Company used. With these in the examples referred to as H-O-M values and with this device For certain measurement data, high values mean that the graciousness is insufficient and therefore disadvantageous. A lower H-O-M value corresponds to a softer paper. For the measurement, two paper samples measuring 11.4 × 11.4 cm were placed side by side placed over the device's 6.4 mm wide slot under the unit's blade. To determine the The H-O-II value in the paper running direction became the paper running direction of the sample arranged parallel to the blade of the device. For determining the H-O-M value across the direction of paper travel the paper direction of the sample was arranged perpendicular to the blade of the measuring device. In the following examples are

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the values read directly from the standard 50 micro-ammeter placed on the measuring device are given.

To quantify the paper properties in terms of surface grip and drape properties were worked according to the principles of textile testing. The handle concerns how the name suggests the feeling triggered by the material and thus depends on the tactile ability. When evaluating the handle of fabrics are the sensations of stiffness or slackness, hardness or softness and roughness or Perceived smoothness together. Drapability has a different meaning and can be used more generally than that Describe the ability of a cloth to look pleasing when used. The experiences of the textile industry show that tissue stiffness is a key factor in the Investigation of handle and drapability is.

A device developed for the textile industry to measure fabric stiffness is the so-called "Shirley Stiffness" Tester ". For comparing drapability and surface grip properties of paper samples made using the different sides of a half-twill embossed fabric v / aren, a "Shirley Stiffness Tester" was used to determine the "bending length" of the paper samples and thus Modified to calculate values for "Flexural stiffness" and "Flexural modulus".

The "Shirley Stiffness Tester" is in American industrial standards, ASTM Standard Method No. 1388. The horizontal platform of the device is made up of two side pieces worn from plastic. These side pieces are engraved with index lines at the standard deflection angle of 41.5 A mirror is attached to the instrument with which the operator

409 88 1 / 0-9 45

person can view both index lines from a suitable position. The scale of the instrument is divided into cm. The scale can be used as a template to cut out the test pieces.

For the test, a rectangular paper strip with dimensions of 15.2 × 2.54 cm is cut to the size of the scale. Then the scale and sample are transferred to the platform with the sample on the bottom. The sample and scale are then slowly pushed forward. The paper strip begins to hang down over the edge of the platform when the scale and sample are pushed forward. The scale and sample continue to move until the tip of the sample, when viewed in the mirror, intersects both index lines. The dimension of the overhang "X" can be read directly from the scale marking opposite a zero line engraved on the side of the platform.

Since paper shows permanent set after such a stiffness test was carried out, four individual samples were made used to test the stiffness of the paper along a given axis} and this was then the mean value for this special axis calculated. The samples were placed in an axis of the direction of travel of the paper, one that was perpendicular to the direction of travel of the paper Axis, an axis corresponding to CD + 30, an axis transverse to this and an axis CD + 135 and cut transversely to this. From the values determined both along and perpendicular to each of the three axes mentioned, for each paper sample a mean overhang value "I" is calculated.

The bend length "c" is defined for this test method as that paper length that is under its own weight bends to a certain extent. This is a measure for that Stiffness, which determines the drapability. The calculation is as follows:

A09881 / 0945

"c" = "I" cm χ f (6), where f (θ) = / cos 1/2 θ τ 8 tan ββ ² , and "'" = the mean overhang value of the respective paper sample according to the above determination.

With the Shirley Stiffness Tester the angle θ = 41.5, whereby the angle f (Θ) or f (41.5 °) = 0> 5. Accordingly the above calculation is simplified as follows:

"c" = "I" χ (0.5) cm

The stiffness, "G," is a hatred for those with the handle related stiffness. The calculation of the bending stiffness "G" is done in the present case as follows:

"G" = 0.1692 χ (weight per unit area of the

2 wavy paper sample in pounds / 3000 feet * ") χ "c" «mg« cm, where "c" is the bending length of the respective paper sample according to the above determination method in cm.

The flexural modulus "q" given in the following examples is independent of the dimensions of the tested strip and can be viewed as the "inherent stiffness" of the material. Accordingly, this value can be used to compare the stiffness used by materials of different thicknesses. The thickness of the paper sample must be used to calculate this value

2
can be measured at a pressure of 70 g / cm.

The flexural modulus "q" is then given by: "q" = 732 χ ¹¹ G "τ" g " ³ kg / cm ²

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where ¹¹ G "is the flexural rigidity of the respective paper sample according to the above determination / expressed in mg · cm, and" g "is the thickness of the respective paper sample in units of 0.025 mm

2 at a pressure of 70 g / cm on the sample.

The test results of paper samples obtained after the test runs described above are in the following examples indicated by the flexural modulus "q", which is both a drape property as well as in relation to the surface attack stands. A lower flexural modulus corresponds to an improved drapability and, accordingly, an improved one Surface grip.

The embossed cusp areas indicated in the following examples were determined using pressure-sensitive Paper in each of four areas on the area in contact with the paper web in the respective example used embossing fabric an impression was made. Each of these four prints were enlarged photographs taken, each uptake being a "unit cell" of cusps; H. comprises a repeating hump pattern. The total area of each unit cell comprised and the total area of those present in such a unit cell Stool was then measured and the results given as a percentage of the cusp area. In the respective example is the mean value indicated by four separate unit cells as the embossed cusp area.

In the examples, the properties of finished material are grounded from paper samples made according to the invention with the properties of paper samples that using the conventional face of a similar embossed fabric in various stages of fabric treatment have been compared.

AO 3 88 1 / 0.9 4 5

EXAMPLE I

Back of the embossing fabric in contact with the

Paper web

Sample no. k 1 1 1 1 §. 1

Bending module "q"

(kg / cm ² ) 10.27 10.25 10.38 9.00 7.38 9.08 8.38

Extensibility

CD (%) 2.0 3.0 3.0 3.0 3.0 2.5 3.0

Extensibility

MD (%) 16.5 17.0 18.0 19.0 19.0 20.0 16.5

H-O-M value CD 3.0 2.75 3.0 2.5 2.75 3.0 3.0 H-O-M value MD 3.25 6.25 11.25 8.5 6.25 10.5 9.5 Tensile strength

CD (g / 2.54 cm) 224 170 161 116 114 248 183 tensile strength

MD (g / 2.54 cm) 251 259 325 268 181 251 219 surface weight

(g / m ² ) 25.1 26.9 25.2 24.4 25.7 24.4 25.2

Embossed cusp area (%) 21.2 21.2 21.2 21.2 21.2 21.2 21.2

Thickness at

12.4 g / cm ²

(Micron) 269 264 269 274 295 272 272

409881/0945

EXAMPLE II

Usual front of the embossing fabric in contact with

the paper web

Sample Mr. λ 1 1 i 1 §. 1

Bending module "q"

(kg / cm ² ) 11.33 11.04 8.60 12.27 21.60 22.01 10.21

Extensibility

CD (% ■) 3.0 2.0 2.0 2.0 2.0 3.0 2.5

Extensibility

HD (%) 20.0 21.0 20.5 20.0 21.0 19.5 22.0

H-O-M value CD 2.0 2.0 2.0 2.0 3.0 2.5 3.0 H-O-M value MD 7.0 8.25 8.50 8.25 11.5 10.5 10.5 Tensile strength

CD (g / 2.54 cm) 144 147 130 141 241 194 194 tensile strength

MD (g / 2.54 cm) 209 199 155 175 331 350 266

Basis weight
(g / m ² ) 25.8 25.2 24.6 24.9 25.1 24.7 24.9

Embossed cusp area (%) 23.4 23.4 23.4 23.4 23.4 23.4 23.4

Thickness at

12.4 g / cm ²

(Micron) 254 259 269 267 231 246 272

409881/0945

EXAMPLE III

The reverse side of the embossed fabric is in contact with the paper web

Sample No. 1 2: 2 1 1 e.1

Bending module "q"
(kg / cm ² ) 10.53 8.41 11.12 5.76 5.76 10.50 8.37

Extensibility

CD (%) 3.5 3.5 3.5 4.0 3.5 3.0 4.5

Extensibility

MD (%) 13.5 19.5 19.0 19.0 18.0 20.5 20.5

H-0-M value CD 2.3 2.0 2.0 2.0 2.0 2.5 2.0 H-O-M value HD 7.0 5.30 10.5 6.5 6.80 10.0 5.3 Tensile strength

CD (g / 2.54 cm) 218 159 221 153 150 266 190 tensile strength

MD (g / 2.54 cn) 278 280 300 199 19 3 299 275 basis weight

(g / m ² ) 27.5 25.6 24.8 23.9 24.6 25.1 26.1

Cusp r ρ r äge -

area (%) 28.4 28.4 28.4 28.4 28.4 28.4 28.4

Thickness at
12.4 g / cm
(Micron) 246 267 252 207 267 2b2 2Ü7

40 98 81/0945

EXAMPLE IV

Usual embossing front side in contact with

the paper web

Sample no. k 1 1 1 1 §. 1

Bending module "q"

(kg / cm ² ) 19.64 26.35 20.11 20.68 18.41 14.82 16.00

Extensibility

CD (%) 2.0 2.0 2.5 3.0 2.0 2.5 3.0

Extensibility

HD (%) 26.5 26.5 24.0 21.5 21.5 25.0 24.0

H-O-M value CD 2.0 3.0 2.0 2.0 2.5 2.0 2.0 H-O-M value MD 11.5 16.5 14.5 9.75 15.5 12.5 9.5 Tensile strength

CD (g / 2.54 cm) 241 295 201 174 196 191 190 tensile strength

MD (g / 2.54 cm) 410 471 330 291 255 290 263

Basis weight
(g / m ² ) 25.1 25.9 25.4 24.3 24.9 25.2 23.9

Embossed cusp area (%) 34.1 34.1 34.1 34.1 34.1 34.1 34.1

Thickness at

12.4 g / cm ²

(Micron) 226 221 231 229 236 246 236

409881/0945

EXAMPLE V

Embossed fabric back in contact with the

Paper web

Sample No. 1 2 3 _4 _5 £ 7.

Bending module "q"

(kg / cm ² ) 8.75 6.07 10.48 6.73 6.03 9.25 6.80

Extensibility

CD (%) 5.0 5.0 5.5 5.5 5.0 5.5 5.5

Extensibility

MD (%) 19.2 21.5 20.5 19.5 19.5 21.0 20.5

H-O-H value CD 2.5 2.0 2.5 2.0 2.0 2.5 2.0 H-O-M value TID 6.0 5.5 7.0 5.5 5.80 9.0 5.5 Tensile strength

CD (g / 2.54 cm) 188 164 243 171 136 191 200 tensile strength

MD (g / 2.54 cm) 269 268 338 271 206 265 259

Basis weight
(g / m ² ) 25.2 26.7 25.4 24.6 25.9 26.2 25.7

Embossed cusp area (%) 37.3 37.3 37.3 37.3 37.3 37.3 37.3

Thickness at
12.4 g / cm
(Micron) 234 251 249 236 251 272 251

409881/0945

EXAMPLE VI

usual embossing face in contact with

Paper web

Sample no. λ 1 1 1

Bending module "q"

(kg / cm ² ) 26.53 22.04 20.6G 15.66

Stretchability CD

(%) 2.0 2.0 2.0 2.0

Extensibility MD

(%) 24.0 23.5 23.0 23.0

H-0-M-Weri CD. 2.0 2.0 2.0 2.0 H-O-M value HD 10.25 12.5 14.5 12.25

Tear strength CD

(g / 2.54 cm) 216 209 228 213

Tear strength MD

(g / 2.54 cm) 315 303 300 304

Basis weight

(g / m ² ) 25.1 23.3 24.1 23.6

Cusp embossing area
(%) 40.0 40.0 40.0 40.0

Thickness at 12.4 g / cm
(Microns) 216 221 224 231

409881/0945

The values compiled in the above examples clearly show the advantages of the present invention in production of paper with significantly improved values for transverse stretchability, softness, surface feel and dra- ~ pierceability.

409881/0945

Claims (7)

Claims 1. Process for the production of soft, thick-grip, absorbent paper , characterized by (a) Forming an uncompacted paper web with a 2 uniform weight per unit area of about 8-65 g / m , (b) Supporting the uncompacted paper web on the back a half-twill embossing fabric with about 7 to about 24 meshes / cm, the hump embossing surface on the The back of the tissue, measured in the cusp level, makes up about 20 to about 50% of the total tissue area and the embossing fabric is formed from filaments with diameters of about 0.2 to about 0.64 mm, (c) thermal predrying of the uncompacted paper web to a fiber consistency of about 30 to about 98%, (d) Embossing a semicolon bump pattern with the halftone embossing fabric such that the longitudinal axes of the • Line embossing of the pattern parallel to the running direction of the pre-dried, uncompacted paper web, and (e) final drying and creping of the so formed Paper. 2, the method according to claim 1, characterized in that Ca) the uniform basis weight of the uncompacted 2 paper web is about 14 to about 41 g / m 2, and ic) the uncompacted paper web thermally to a fiber consistency is predried from about 40 to about 98%. 3. The method according to claim 1 or 2, characterized in that that the final drying of the paper takes place on the embossing fabric. 4. The method according to claim 1 or 2, characterized in that that the final drying of the paper takes place on a self-acceptance drying drum and that Creping is carried out with the help of a scraper. 5. The method according to claim 1 or 2, characterized in that the uncompacted paper web formed in step (a) is shaped before the thermal pre-drying of the uncompacted paper web according to step (c) to match the pattern of the embossing fabric. 6. Soft, thick-grip, absorbent paper, marked due to a uniform basis weight of about 8-65 g / n ^ and at least 30% of the machine-smooth Paper-thick, deep surface embossing with the cusp pattern of the back of a half-twill embossing fabric with about S to about 24 meshes / cm, with about 20 to about 50% of the paper surface are condensed in a line / dot pattern in such a way that the longitudinal axes of the line embossings of the pattern are parallel to the direction of travel of the paper during the formation of the paper, and the paper also a transverse stretchability of about 3.5 to about 6%. having. 7. Paper according to claim 6, characterized in that it has a diamond-shaped surface after creping Pattern shows. r l / ßi For: The Procter JkI Gamble Company (Dr HiJ Wolff) Lawyer 0 9 8 8 1/0945 Blank page