CA2255217A1 - Method and apparatus for making a softer, more absorbent no press, no crepe towel - Google Patents
Method and apparatus for making a softer, more absorbent no press, no crepe towel Download PDFInfo
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- CA2255217A1 CA2255217A1 CA 2255217 CA2255217A CA2255217A1 CA 2255217 A1 CA2255217 A1 CA 2255217A1 CA 2255217 CA2255217 CA 2255217 CA 2255217 A CA2255217 A CA 2255217A CA 2255217 A1 CA2255217 A1 CA 2255217A1
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Abstract
A method and apparatus for making a softer, more absorbent no press, no crepe towel. This invention relates generally to an absorbent web and a method for preparing the absorbent web. More particularly, the invention relates to a softer, more absorbent cellulosic web made without significant pressing or creping of the web.
Description
CA 022~217 1998-12-21 METHOD AND APPARATUS FOR MAKING A SOFTER, MORE
ABSORBENT NO PRESS, NO CREPE TOWEL
Technical Field This invention relates generally to an absorbent web, such as tissues towels and wipes, and to a method for preparing the absorbent web. More particularly, the invention relates to a softer, more absorbent cellulosic web or cellulosic sheet.
1 0 Background Cellulosic web-based products, such as hand towels, wipers, and the like, are widely manufactured in the paper making industry. Each product has unique characteristics requiring appropriate attributes. The proper attributes ensure that the product is suitable for its intended purpose.
During manufacture of many cellulosic webs, the web is pressed or creped during or after drying in order to impart tensile strength. This pressing or creping can detrimentally influence the softness and absorbency of the web, and requires an additional manufacturing step or steps that can add complexity and cost to the formation of the webs. The pressing and creping can increase stiffness of the web, and take away from absorbency.
For many products, high tensile strength and high water absorbency are important properties. Tensile strength of cellulosic webs is often measured under dry conditions to determine "dry-tensile strength", and under wet conditions to determine "wet-tensile strength". Wet-tensile strength and dry-tensile strength are often closely related. Products having high dry-tensile strength frequently have high wet-tensile strength. The relationship between dry-tensile strength and wet-tensile CA 022~217 1998-12-21 strength occurs, in part, because certain manufacturing processes enhance both properties. For example, pressing a cellulosic web under high pressure often imparts increased dry-tensile and wet-tensile strengths. As noted above, the pressing of the web under high pressure can be disadvantageous if it reduces the absorbency of the 5 web or makes the web stiffer.
A cellulosic web must have adequate dry-tensile strength and adequate wet-tensile strength. However, since cellulosic webs often deteriorate and lose strength when wet, wet-tensile strength is normally significantly lower than dry-tensile strength. Thus, many cellulosic webs have inadequate wet-tensile strength, even 10 though they have adequate dry-tensile strength.
While a hand towel must have some dry-tensile strength, high dry-tensile strength can be disadvantageous because it correlates closely with stiffness and stiff webs. Hand towels manufactured from stiff webs are received with disfavor by consumers, since the towels do not have the soft feel of traditional cotton hand 15 towels. In contrast, consumers desire high wet-tensile strength, because it allows more vigorous use of the hand towel to pick up spills and scrub wet soiled surfaces.
The relationship between wet-tensile and dry-tensile is often expressed as a tensile strength ratio in which wet-tensile strength is divided by dry-tensile strength to get the wet/dry tensile ratio (wet-tensile value in numerator, dry-tensile value in 20 denominator). The wet/dry tensile ratio is normally less than 0.3, since the wet-tensile strength is usually significantly less than the dry-tensile strength. The ratio is preferably greater than 0.8, greater than or as close to 1 as possible, since this CA 022~217 1998-12-21 indicates a high wet-tensile strength relative to dry-tensile strength. Cellulosic webs with high wet/dry tensile ratios are soft, yet strong.
Therefore, a need exists for an improved cellulosic web that has sufficient strength and absorbency, but is not pressed or creped so as to m~int~in softness.
Summary of the Invention The present invention provides an improved method for making a cellulosic web, as well as a web made using the improved method. The method includes forming a finished cellulosic web without pressing or creping. A debonder and a 10 wetting agent, or a debonding wetting agent, are added to the papermaking furnish or the web prior to drying. The finished web has improved absorbency and advantageous wet-strength to dry-strength ratios.
A specific implementation of the method of the invention includes providing a papermaking furnish containing a cellulosic material and water. An effective amount of between 0.25 and 2.0 weight percent of a wet-strength resin is added to the cellulosic material based on the dry-weight of the cellulosic material. In addition, an effective amount, between 0.1 percent and 1.0 percent, of a debonder is added based on the dry-weight of the cellulosic material; and between 0.1 and 1.0 percent of a hydroscopic wetting agent is added to the paperm~king furnish. A
20 cellulosic web is formed from the paperm:~king furnish and dried without pressing and crepmg.
In another implementation, the cellulosic web is formed by adding a wet-strength resin to a paperm~king furnish containing a cellulosic material and water.
CA 022~217 1998-12-21 A hydroscopic cationic wetting agent having debonding properties is added to thepaperm~king furnish, which in turn is dewatered and formed into a cellulosic webthat is dried without pressing or creping to form an improved web having advantageous wet-strength and absorbency properties.
The above summary of the present invention is not intended to describe each discussed embodiment of the present invention. While the invention is susceptible to various modifications and alternative forms, specifics thereof will be described in detail. It should be understood, however, that the intention is not to limit theinvention to particular embodiments described. On the contrary, the intention is to cover modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Detailed Description of the Invention The present invention is directed to an improved method for making a cellulosic web, as well as a web made using the improved method. The method includes addition of surfactant and wet strength resin to a paperm~king furnish. The resulting paperm~king furnish is formed into a cellulosic web. A debonder and a wetting agent are added to the paperm~king furnish or the web prior to drying.
Alternatively, a wetting agent having debonding properties is added to the furnish or web prior to drying. The finished web has improved absorbency and advantageous wet-strength to dry-strength ratios.
A specific implementation of the method of the invention includes providing a papermaking furnish cont~ining a cellulosic material and water. Between about CA 022~217 1998-12-21 0.25 and 2 weight percent of wet-strength resin is added to the cellulosic material based on the dry-weight of the cellulosic material. In addition, between about 0.1 percent and 1 percent of a debonder is added based on the dry-weight of the cellulosic material. Between about 0.1 and 1 percent of a hydroscopic wetting agent 5 is also added to the paperm~king furnish. A cellulosic web is formed from the paperm~king furnish and dried without pressing and creping.
In another implementation, the cellulosic web is formed by adding between about 0.25 and 2 percent by weight of a wet-strength resin to a paperm~king furnish containing a cellulosic material and water. A hydroscopic cationic wetting agent 10 having debonding properties is added at between about 0.1 and 2 weight percent to the paperm~king furnish, which in turn is dewatered and formed into a cellulosic web that is dried without pressing or creping to form an improved web having advantageous wet-strength and absorbency properties. This web is subsequently dried in accordance with conventional paper making methods, including drying 15 without pressure and without creping. The finished web has improved strength properties, for example, improved wet-tensile strength and an improved wet-tensile strength to dry-tensile strength ratio (wet/dry tensile ratio).
The method includes providing a paperm~king furnish cont~ining a cellulosic material and water. The cellulosic material is, for example, Northern Soft Wood 20 Kraft (NSWK), chemi-thermo-mechanical pulp (CTMP), natural redwood (RW), Mobile Pine (MP), or a recycled wood fiber, such as bleached recycled office waste fiber.
CA 022~217 1998-12-21 While the present invention is not limited to a specific hydroscopic wetting agent, appropriate ones include any hydropohillic anionic, nonionic or cationic wetting agent such as an anionic sulfonate, Witco 5175-26A, manufactured by the Witco Chemical Co., nonionic polyethylene glycols (PEGs), quaternary ammonium compounds, Incroquat AQ, and Glucoquat 125. Appropriate PEGs include PEG
300, PEG 400, and PEG 600. Witco 5175-26A includes a significant sulfonate component, and certain appropriate hydroscopic wetting agents include an anionicalkyl sulfate or anionic alkyl sulfonate component. Other acceptable hydroscopicwetting agents include Witco EP-5327-97 and EP-5293-150, also manufactured by the Witco Chemical Co. In addition to the anionic alkyl sulfate or anionic alkylsulfonate component, the hydroscopic wetting agent may include other wetting agents to improve water compatibility and absorbency on the fiber.
The wet-strength resin is preferably water soluble. Suitable resins include polyamide-epichlorohydrin resins such as those sold by Hercules Incorporated of Wilmington, Delaware, under the brand name Kymene 557H and Kymene 2064.
These resins include low molecular weight polymers having reactive functional groups, including epoxy and amino groups. In certain implementations, the wet-strength resin is added at a rate of between about 5.0 and 30 pounds per ton of cellulosic material.
The resulting cellulosic web has improved wet-tensile strength as well as an improved ratio of wet-tensile strength to dry-tensile strength . Referring now to the tables produced below, example formulations of cellulosic webs constructed in accordance with the present invention are shown.
CA 022~217 1998-12-21 Example 1 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = none Basis Weight (BW): 25.9 Machine Direction Tensile (MDT): 54 Machine Direction Strength (MDS): 13 Cross Directional Tensile (CDT): 31 Cross Directional Strength (CDS): 6 Cured Cross Direction Wet Tensile (CCDWT): 8.9 Balk / Basis Weight (BLK/B.W.): 15.2 XY Wick: 0.17 Wet/Dry: 28.6 Example 2 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = 0.7% Witco 5175-26A added to the wet end.
Basis Weight (BW): 28.4 Machine Direction Tensile (MDT): 40 Machine Direction Strength (MDS): 12 Cross Directional Tensile (CDT): 23 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 7.4 Balk / Basis Weight (BLK/B.W.): 14.1 XY Wick: 0.19 Wet/Dry: 32.3 CA 022~217 1998-12-21 Example 3 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = 0.7% Witco 5175-26A added to the wet end and 0.3% Witco 5175-26A
added at the through dried wire.
Basis Weight (BW): 27.4 Machine Direction Tensile (MDT): 34 Machine Direction Strength (MDS): 12 Cross Directional Tensile (CDT): 22 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 7.3 Balk / Basis Weight (BLK/B.W.): 16 XY Wick: .22 Wet/Dry: 33 3 Example 4 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = 0.7% Glucoquat 125 added to the wet end and 0.3% Glucoquat 125 added at the through dried wire.
Basis Weight (BW): 26.2 Machine Direction Tensile (MDT): 42 Machine Direction Strength (MDS): 11 Cross Directional Tensile (CDT): 27 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 8.2 Balk / Basis Weight (BLK/B.W.): 15 XY Wick: 0.22 Wet/Dry: 30.2 Example 1 shows a mixed pulp furnish with Kymene 557H wet strength resin containing polyamide epichlorohydrin resins, but no other debonders , CA 022~217 1998-12-21 or hydroscopic wetting agents. Examples 2, 3, and 4 show the mixed pulp furnish with Kymene 557H wet strength resin along with hydroscopic wetting agent additives, and indicate a reduction in dry tensile, measured as machine direction tensile (MDT), of 37 percent, with only a 7 to 17 percent loss in wet tensile measured as cured cross direction 5 wet tensile (CCDWT). In addition, a wicking speed increase of 30 percent is obtained, along with improvements in the wet/dry tensile ratio. The sample from Example 3 shows a noticeably softer and more absorbent cellulosic web with small changes to the wet strength. The methods of examples 2, 3, and 4 allow production of a soft towel by a no press, no crepe (NPNC) or no press, no crepe (NPNC)/restrained drying technique.
10 A permanent pattern may be imparted onto the web by using a coarse through-dried wire for formation of the cellulosic web.
Example 5 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 1.0%
Kymene 557H.
Additive = none.
Basis Weight (BW): 25.8 Machine Direction Tensile (MDT): 59 Machine Direction Strength (MDS): 11 Cross Directional Tensile (CDT): 31 Cross Directional Strength (CDS): 6 Cured Cross Direction Wet Tensile (CCDWT): 10.7 Balk / Basis Weight (BLK/B.W.): 15.6 XY Wick: 0.16 Wet/Dry: 34 9 CA 022~217 1998-12-21 Example 6 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 1.0%
Kymene 557H.
Additive = 0.7% Witco 5175-26A added to the wet end and 0.3% Witco 5175-26A
added at the through dried wire.
Basis Weight (BW): 26.1 Machine Direction Tensile (MDT): 50 Machine Direction Strength (MDS): 13 Cross Directional Tensile (CDT): 27 Cross Directional Strength (CDS): 6 Cured Cross Direction Wet Tensile (CCDWT): 9.5 Balk / Basis Weight (BLK/B.W.): 15.1 XY Wick: 0.21 Wet/Dry: 36.0 Example 7 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 1.0%
Kymene 557H.
Additive = 0.7% Incroquat AQ added to the wet end and 0.3% Incroquat AQ added atthe through dried wire.
Basis Weight (BW): 25.5 Machine Direction Tensile (MDT): 50 Machine Direction Strength (MDS): 13 Cross Directional Tensile (CDT): 32 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 11.7 Balk / Basis Weight (BLK/B.W.): 15.5 XY Wick: 0.21 Wet/Dry: 36.7 CA 022~217 1998-12-21 Example 8 Furnish = 40% Mobile Wet Lap Pine,30% recycled fiber,30% CTMP, and 1.0%Kymene 557H.
Additive = 0.2% Aerosurf PA-801 debonder added at the wet end.
Basis Weight (BW): 32.6 Machine Direction Tensile (MDT): 57 Machine Direction Strength (MDS): 14 Cross Directional Tensile (CDT): 37 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 14.0 Balk / Basis Weight (BLK/B.W.): 14.0 XY Wick: 0.11 Wet/Dry: 38.1 Examples 6 and 7 show significant improvements in wicking speeds while reducing tensile and improving the wet/dry ratio.
Example 9 Furnish = 40% NSWK,30% CTMP,30% Eucalyptus, and 0.6% Kymene 557H.
Additive = 0.3% polyethylene glycol 300 added at the through dried wire.
Basis Weight (BW): 25.9 Machine Direction Tensile (MDT): 60 Machine Direction Strength (MDS): 17 Cross Directional Tensile (CDT): 28 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 10.0 Balk / Basis Weight (BLK/B.W.): 16.0 XY Wick: 0.10 Wet/Dry: 34.7 CA 022~217 1998-12-21 Example 10 Furnish = 40% NSWK, 30% CTMP, 30% Eucalyptus, and 0.6% Kymene 557H.
Additive = 0.4% of Arosurf PA801 was added to the paper furnish and 0.3%
polyethylene glycol was added to the web at the through-dried wire.
Basis Weight (BW): 26.9 Machine Direction Tensile (MDT): 25 Machine Direction Strength (MDS): 14 Cross Directional Tensile (CDT): 14 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 6.6 Balk / Basis Weight (BLK/B.W.): 15.6 XY Wick: 0.14 Wet/Dry: 43. 1 Examples 9 and 10 show a combination of debonder and post-formed addition of polyethylene glycol 300 reduces dry tensile by over 60%, while wet tensile was reduced only 34%. The wet/dry ratio increased to 43%, giving a significantly softer towel.
While the present invention has been described with reference to several particular implementations, those skilled in the art will recognize that many changes may be made hereto without departing form the spirit and scope of the present invention.
ABSORBENT NO PRESS, NO CREPE TOWEL
Technical Field This invention relates generally to an absorbent web, such as tissues towels and wipes, and to a method for preparing the absorbent web. More particularly, the invention relates to a softer, more absorbent cellulosic web or cellulosic sheet.
1 0 Background Cellulosic web-based products, such as hand towels, wipers, and the like, are widely manufactured in the paper making industry. Each product has unique characteristics requiring appropriate attributes. The proper attributes ensure that the product is suitable for its intended purpose.
During manufacture of many cellulosic webs, the web is pressed or creped during or after drying in order to impart tensile strength. This pressing or creping can detrimentally influence the softness and absorbency of the web, and requires an additional manufacturing step or steps that can add complexity and cost to the formation of the webs. The pressing and creping can increase stiffness of the web, and take away from absorbency.
For many products, high tensile strength and high water absorbency are important properties. Tensile strength of cellulosic webs is often measured under dry conditions to determine "dry-tensile strength", and under wet conditions to determine "wet-tensile strength". Wet-tensile strength and dry-tensile strength are often closely related. Products having high dry-tensile strength frequently have high wet-tensile strength. The relationship between dry-tensile strength and wet-tensile CA 022~217 1998-12-21 strength occurs, in part, because certain manufacturing processes enhance both properties. For example, pressing a cellulosic web under high pressure often imparts increased dry-tensile and wet-tensile strengths. As noted above, the pressing of the web under high pressure can be disadvantageous if it reduces the absorbency of the 5 web or makes the web stiffer.
A cellulosic web must have adequate dry-tensile strength and adequate wet-tensile strength. However, since cellulosic webs often deteriorate and lose strength when wet, wet-tensile strength is normally significantly lower than dry-tensile strength. Thus, many cellulosic webs have inadequate wet-tensile strength, even 10 though they have adequate dry-tensile strength.
While a hand towel must have some dry-tensile strength, high dry-tensile strength can be disadvantageous because it correlates closely with stiffness and stiff webs. Hand towels manufactured from stiff webs are received with disfavor by consumers, since the towels do not have the soft feel of traditional cotton hand 15 towels. In contrast, consumers desire high wet-tensile strength, because it allows more vigorous use of the hand towel to pick up spills and scrub wet soiled surfaces.
The relationship between wet-tensile and dry-tensile is often expressed as a tensile strength ratio in which wet-tensile strength is divided by dry-tensile strength to get the wet/dry tensile ratio (wet-tensile value in numerator, dry-tensile value in 20 denominator). The wet/dry tensile ratio is normally less than 0.3, since the wet-tensile strength is usually significantly less than the dry-tensile strength. The ratio is preferably greater than 0.8, greater than or as close to 1 as possible, since this CA 022~217 1998-12-21 indicates a high wet-tensile strength relative to dry-tensile strength. Cellulosic webs with high wet/dry tensile ratios are soft, yet strong.
Therefore, a need exists for an improved cellulosic web that has sufficient strength and absorbency, but is not pressed or creped so as to m~int~in softness.
Summary of the Invention The present invention provides an improved method for making a cellulosic web, as well as a web made using the improved method. The method includes forming a finished cellulosic web without pressing or creping. A debonder and a 10 wetting agent, or a debonding wetting agent, are added to the papermaking furnish or the web prior to drying. The finished web has improved absorbency and advantageous wet-strength to dry-strength ratios.
A specific implementation of the method of the invention includes providing a papermaking furnish containing a cellulosic material and water. An effective amount of between 0.25 and 2.0 weight percent of a wet-strength resin is added to the cellulosic material based on the dry-weight of the cellulosic material. In addition, an effective amount, between 0.1 percent and 1.0 percent, of a debonder is added based on the dry-weight of the cellulosic material; and between 0.1 and 1.0 percent of a hydroscopic wetting agent is added to the paperm~king furnish. A
20 cellulosic web is formed from the paperm:~king furnish and dried without pressing and crepmg.
In another implementation, the cellulosic web is formed by adding a wet-strength resin to a paperm~king furnish containing a cellulosic material and water.
CA 022~217 1998-12-21 A hydroscopic cationic wetting agent having debonding properties is added to thepaperm~king furnish, which in turn is dewatered and formed into a cellulosic webthat is dried without pressing or creping to form an improved web having advantageous wet-strength and absorbency properties.
The above summary of the present invention is not intended to describe each discussed embodiment of the present invention. While the invention is susceptible to various modifications and alternative forms, specifics thereof will be described in detail. It should be understood, however, that the intention is not to limit theinvention to particular embodiments described. On the contrary, the intention is to cover modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Detailed Description of the Invention The present invention is directed to an improved method for making a cellulosic web, as well as a web made using the improved method. The method includes addition of surfactant and wet strength resin to a paperm~king furnish. The resulting paperm~king furnish is formed into a cellulosic web. A debonder and a wetting agent are added to the paperm~king furnish or the web prior to drying.
Alternatively, a wetting agent having debonding properties is added to the furnish or web prior to drying. The finished web has improved absorbency and advantageous wet-strength to dry-strength ratios.
A specific implementation of the method of the invention includes providing a papermaking furnish cont~ining a cellulosic material and water. Between about CA 022~217 1998-12-21 0.25 and 2 weight percent of wet-strength resin is added to the cellulosic material based on the dry-weight of the cellulosic material. In addition, between about 0.1 percent and 1 percent of a debonder is added based on the dry-weight of the cellulosic material. Between about 0.1 and 1 percent of a hydroscopic wetting agent 5 is also added to the paperm~king furnish. A cellulosic web is formed from the paperm~king furnish and dried without pressing and creping.
In another implementation, the cellulosic web is formed by adding between about 0.25 and 2 percent by weight of a wet-strength resin to a paperm~king furnish containing a cellulosic material and water. A hydroscopic cationic wetting agent 10 having debonding properties is added at between about 0.1 and 2 weight percent to the paperm~king furnish, which in turn is dewatered and formed into a cellulosic web that is dried without pressing or creping to form an improved web having advantageous wet-strength and absorbency properties. This web is subsequently dried in accordance with conventional paper making methods, including drying 15 without pressure and without creping. The finished web has improved strength properties, for example, improved wet-tensile strength and an improved wet-tensile strength to dry-tensile strength ratio (wet/dry tensile ratio).
The method includes providing a paperm~king furnish cont~ining a cellulosic material and water. The cellulosic material is, for example, Northern Soft Wood 20 Kraft (NSWK), chemi-thermo-mechanical pulp (CTMP), natural redwood (RW), Mobile Pine (MP), or a recycled wood fiber, such as bleached recycled office waste fiber.
CA 022~217 1998-12-21 While the present invention is not limited to a specific hydroscopic wetting agent, appropriate ones include any hydropohillic anionic, nonionic or cationic wetting agent such as an anionic sulfonate, Witco 5175-26A, manufactured by the Witco Chemical Co., nonionic polyethylene glycols (PEGs), quaternary ammonium compounds, Incroquat AQ, and Glucoquat 125. Appropriate PEGs include PEG
300, PEG 400, and PEG 600. Witco 5175-26A includes a significant sulfonate component, and certain appropriate hydroscopic wetting agents include an anionicalkyl sulfate or anionic alkyl sulfonate component. Other acceptable hydroscopicwetting agents include Witco EP-5327-97 and EP-5293-150, also manufactured by the Witco Chemical Co. In addition to the anionic alkyl sulfate or anionic alkylsulfonate component, the hydroscopic wetting agent may include other wetting agents to improve water compatibility and absorbency on the fiber.
The wet-strength resin is preferably water soluble. Suitable resins include polyamide-epichlorohydrin resins such as those sold by Hercules Incorporated of Wilmington, Delaware, under the brand name Kymene 557H and Kymene 2064.
These resins include low molecular weight polymers having reactive functional groups, including epoxy and amino groups. In certain implementations, the wet-strength resin is added at a rate of between about 5.0 and 30 pounds per ton of cellulosic material.
The resulting cellulosic web has improved wet-tensile strength as well as an improved ratio of wet-tensile strength to dry-tensile strength . Referring now to the tables produced below, example formulations of cellulosic webs constructed in accordance with the present invention are shown.
CA 022~217 1998-12-21 Example 1 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = none Basis Weight (BW): 25.9 Machine Direction Tensile (MDT): 54 Machine Direction Strength (MDS): 13 Cross Directional Tensile (CDT): 31 Cross Directional Strength (CDS): 6 Cured Cross Direction Wet Tensile (CCDWT): 8.9 Balk / Basis Weight (BLK/B.W.): 15.2 XY Wick: 0.17 Wet/Dry: 28.6 Example 2 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = 0.7% Witco 5175-26A added to the wet end.
Basis Weight (BW): 28.4 Machine Direction Tensile (MDT): 40 Machine Direction Strength (MDS): 12 Cross Directional Tensile (CDT): 23 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 7.4 Balk / Basis Weight (BLK/B.W.): 14.1 XY Wick: 0.19 Wet/Dry: 32.3 CA 022~217 1998-12-21 Example 3 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = 0.7% Witco 5175-26A added to the wet end and 0.3% Witco 5175-26A
added at the through dried wire.
Basis Weight (BW): 27.4 Machine Direction Tensile (MDT): 34 Machine Direction Strength (MDS): 12 Cross Directional Tensile (CDT): 22 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 7.3 Balk / Basis Weight (BLK/B.W.): 16 XY Wick: .22 Wet/Dry: 33 3 Example 4 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 0.8%
Kymene 557H.
Additive = 0.7% Glucoquat 125 added to the wet end and 0.3% Glucoquat 125 added at the through dried wire.
Basis Weight (BW): 26.2 Machine Direction Tensile (MDT): 42 Machine Direction Strength (MDS): 11 Cross Directional Tensile (CDT): 27 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 8.2 Balk / Basis Weight (BLK/B.W.): 15 XY Wick: 0.22 Wet/Dry: 30.2 Example 1 shows a mixed pulp furnish with Kymene 557H wet strength resin containing polyamide epichlorohydrin resins, but no other debonders , CA 022~217 1998-12-21 or hydroscopic wetting agents. Examples 2, 3, and 4 show the mixed pulp furnish with Kymene 557H wet strength resin along with hydroscopic wetting agent additives, and indicate a reduction in dry tensile, measured as machine direction tensile (MDT), of 37 percent, with only a 7 to 17 percent loss in wet tensile measured as cured cross direction 5 wet tensile (CCDWT). In addition, a wicking speed increase of 30 percent is obtained, along with improvements in the wet/dry tensile ratio. The sample from Example 3 shows a noticeably softer and more absorbent cellulosic web with small changes to the wet strength. The methods of examples 2, 3, and 4 allow production of a soft towel by a no press, no crepe (NPNC) or no press, no crepe (NPNC)/restrained drying technique.
10 A permanent pattern may be imparted onto the web by using a coarse through-dried wire for formation of the cellulosic web.
Example 5 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 1.0%
Kymene 557H.
Additive = none.
Basis Weight (BW): 25.8 Machine Direction Tensile (MDT): 59 Machine Direction Strength (MDS): 11 Cross Directional Tensile (CDT): 31 Cross Directional Strength (CDS): 6 Cured Cross Direction Wet Tensile (CCDWT): 10.7 Balk / Basis Weight (BLK/B.W.): 15.6 XY Wick: 0.16 Wet/Dry: 34 9 CA 022~217 1998-12-21 Example 6 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 1.0%
Kymene 557H.
Additive = 0.7% Witco 5175-26A added to the wet end and 0.3% Witco 5175-26A
added at the through dried wire.
Basis Weight (BW): 26.1 Machine Direction Tensile (MDT): 50 Machine Direction Strength (MDS): 13 Cross Directional Tensile (CDT): 27 Cross Directional Strength (CDS): 6 Cured Cross Direction Wet Tensile (CCDWT): 9.5 Balk / Basis Weight (BLK/B.W.): 15.1 XY Wick: 0.21 Wet/Dry: 36.0 Example 7 Furnish = 40% Mobile Wet Lap Pine, 30% recycled fiber, 30% CTMP, and 1.0%
Kymene 557H.
Additive = 0.7% Incroquat AQ added to the wet end and 0.3% Incroquat AQ added atthe through dried wire.
Basis Weight (BW): 25.5 Machine Direction Tensile (MDT): 50 Machine Direction Strength (MDS): 13 Cross Directional Tensile (CDT): 32 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 11.7 Balk / Basis Weight (BLK/B.W.): 15.5 XY Wick: 0.21 Wet/Dry: 36.7 CA 022~217 1998-12-21 Example 8 Furnish = 40% Mobile Wet Lap Pine,30% recycled fiber,30% CTMP, and 1.0%Kymene 557H.
Additive = 0.2% Aerosurf PA-801 debonder added at the wet end.
Basis Weight (BW): 32.6 Machine Direction Tensile (MDT): 57 Machine Direction Strength (MDS): 14 Cross Directional Tensile (CDT): 37 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 14.0 Balk / Basis Weight (BLK/B.W.): 14.0 XY Wick: 0.11 Wet/Dry: 38.1 Examples 6 and 7 show significant improvements in wicking speeds while reducing tensile and improving the wet/dry ratio.
Example 9 Furnish = 40% NSWK,30% CTMP,30% Eucalyptus, and 0.6% Kymene 557H.
Additive = 0.3% polyethylene glycol 300 added at the through dried wire.
Basis Weight (BW): 25.9 Machine Direction Tensile (MDT): 60 Machine Direction Strength (MDS): 17 Cross Directional Tensile (CDT): 28 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 10.0 Balk / Basis Weight (BLK/B.W.): 16.0 XY Wick: 0.10 Wet/Dry: 34.7 CA 022~217 1998-12-21 Example 10 Furnish = 40% NSWK, 30% CTMP, 30% Eucalyptus, and 0.6% Kymene 557H.
Additive = 0.4% of Arosurf PA801 was added to the paper furnish and 0.3%
polyethylene glycol was added to the web at the through-dried wire.
Basis Weight (BW): 26.9 Machine Direction Tensile (MDT): 25 Machine Direction Strength (MDS): 14 Cross Directional Tensile (CDT): 14 Cross Directional Strength (CDS): 5 Cured Cross Direction Wet Tensile (CCDWT): 6.6 Balk / Basis Weight (BLK/B.W.): 15.6 XY Wick: 0.14 Wet/Dry: 43. 1 Examples 9 and 10 show a combination of debonder and post-formed addition of polyethylene glycol 300 reduces dry tensile by over 60%, while wet tensile was reduced only 34%. The wet/dry ratio increased to 43%, giving a significantly softer towel.
While the present invention has been described with reference to several particular implementations, those skilled in the art will recognize that many changes may be made hereto without departing form the spirit and scope of the present invention.
Claims (7)
1. A method of improving the absorbency of a cellulosic web, the method comprising:
providing a papermaking furnish containing a cellulosic material and water;
adding between about 0.25 and 2 wt. % wet-strength resin based on the dry-weight of the cellulosic material;
adding between about 0.1 and 1% debonder based on the dry-weight of the cellulosic material;
adding between about 0.1 and 1 percent hydroscopic wetting agent based on the dry-weight of the cellulosic material; and formation of a cellulosic web from the papermaking furnish and drying the cellulosic web without pressing and without creping.
providing a papermaking furnish containing a cellulosic material and water;
adding between about 0.25 and 2 wt. % wet-strength resin based on the dry-weight of the cellulosic material;
adding between about 0.1 and 1% debonder based on the dry-weight of the cellulosic material;
adding between about 0.1 and 1 percent hydroscopic wetting agent based on the dry-weight of the cellulosic material; and formation of a cellulosic web from the papermaking furnish and drying the cellulosic web without pressing and without creping.
2. The method according to claim 1, wherein the hydroscopic wetting agent includes an alkyl sulfate or an alkyl sulfonate.
3. The method according to claim 1, wherein the hydroscopic wetting agent is a nonionic.
4. The method according to claim 1, wherein the hydroscopic wetting agent is a quaternary ammonium compound.
5. The method according to claim 1, wherein the wet strength resin is a polyamide epichlorohydrin resin.
6. A method of improving the absorbency of a cellulosic web, the method comprising:
providing a papermaking furnish containing a cellulosic material and water;
adding between about 0.25 and 2 percent wet-strength resin;
adding between about 0.1 and 2 percent of a hydroscopic cationic wetting agent having debonding properties.
providing a papermaking furnish containing a cellulosic material and water;
adding between about 0.25 and 2 percent wet-strength resin;
adding between about 0.1 and 2 percent of a hydroscopic cationic wetting agent having debonding properties.
7. A softer, more absorbent no press, no crepe cellulosic web comprising a cellulosic web made with no pressing or creping step further comprising a web comprising a debonder and a wetting agent added to the papermaking furnish or the web prior to drying, saidfinished web having improved absorbency and improved wet-strength to dry-strength ratios.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US7007997P | 1997-12-31 | 1997-12-31 | |
| US60/070,079 | 1997-12-31 | ||
| US20764598A | 1998-12-08 | 1998-12-08 | |
| US09/207,645 | 1998-12-08 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2255217A1 true CA2255217A1 (en) | 1999-06-30 |
Family
ID=29552533
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2255217 Abandoned CA2255217A1 (en) | 1997-12-31 | 1998-12-21 | Method and apparatus for making a softer, more absorbent no press, no crepe towel |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2255217A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2569484B2 (en) † | 2010-05-10 | 2020-05-27 | Papierfabrik Julius Schulte Söhne Gmbh & Co. KG | Core paper |
-
1998
- 1998-12-21 CA CA 2255217 patent/CA2255217A1/en not_active Abandoned
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2569484B2 (en) † | 2010-05-10 | 2020-05-27 | Papierfabrik Julius Schulte Söhne Gmbh & Co. KG | Core paper |
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