CA2147276A1 - Papermaking process - Google Patents
Papermaking processInfo
- Publication number
- CA2147276A1 CA2147276A1 CA002147276A CA2147276A CA2147276A1 CA 2147276 A1 CA2147276 A1 CA 2147276A1 CA 002147276 A CA002147276 A CA 002147276A CA 2147276 A CA2147276 A CA 2147276A CA 2147276 A1 CA2147276 A1 CA 2147276A1
- Authority
- CA
- Canada
- Prior art keywords
- paper
- cellulose
- milling
- oxide
- tertiary amine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/001—Modification of pulp properties
- D21C9/002—Modification of pulp properties by chemical means; preparation of dewatered pulp, e.g. in sheet or bulk form, containing special additives
- D21C9/005—Modification of pulp properties by chemical means; preparation of dewatered pulp, e.g. in sheet or bulk form, containing special additives organic compounds
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Electronic Switches (AREA)
- Making Paper Articles (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
Abstract
A papermaking process in which an aqueous suspension of comminuted cellulose material is treated mechanically and then subjected to a sheet-formingoperation is characterized in that the suspension contains a tertiary amine oxide. The comminuted cellulose material can come in part from wastepaper.
Description
-- 2 1 4 7 2 7 6 ` ` -PROCESS FOR THE PREPARATION OF PAPER
The current invention concerns a process for the preparation of paper in which an aqueous suspension of comminuted cellulose material is mechanically treated and is subjected to a sheet-making process.
It is known that cellulose which is to be processed into paper must be milled before sheet-making. According to DIN 54 360 (November 1977), milling means mechanical treatment of the cellulose in a suspended state during which its physical properties are so changed that it becomes suitable for the preparation of paper. During the milling of the slurry formed by the cellulose fibres and water, the fibres become cut, fibrillated and swollen.
Fibrillation means the splitting of the fibres parallel to the fibre axis. Aftermilling, the greater part of the fibrils remains hanging like frills on the fibres. Swelling and fibrillation are of great importance in the preparation of stron g paper.
The milling process is an energy-intensive process. Among products needing highly-milled fibrous materials, the milling of cellulose is indeed one of the most energy-intensive processes in paper-making. Polymeric saccharides, monomeric and polymeric amines, amides and dyestuffs are recommended as milling aids (M Milichovsky, Chemische Aspekte der Mahlung von Zellstoff:
Zellstoff und Papier, 38, page 17, (1989)). The degree of milling is given in degrees Schopper-Riegler (SR). The strength of the resulting paper generally increases as the degree of milling increases.
Machines such as for instance, Hollander beaters, Jordan mills, refiners, disc mills and pulpers can be used for milling. The stock slurry is processed between a moving part and a fixed part of the machine during the milling process (Handbuch der Papier- und Pappenfabrikation, (Papierlexikon), 2nd Edition, Vol II, L-Z, 1971).
It is moreover known that the strength of a paper can be further increased with additives. Such materials are for example natural rubbers and carboxymethyl cellulose. It is also known from US-A 3 447 956 that paper which has had chemical treatment, wherein it is swollen at a temperature - ~147276 above 100 C in a molten tertiary amine-oxide, has a higher strength.
In US-A 3 503 700 it is said that paper which is soaked in a 25% aqueous solution of a tertiary amine-oxide, dried and heated to above 200tand then cooled and rinsed with water to wash out the tertiary amine-oxide again, has a higher strength after such treatment.
On the other hand problems which occur in the processing of ~steE~per are increasingly described in the literature. A phenomenon well known to the paper-maker is that cellulose fibres which have already been used one or more times for paper-making are no longer very suitable for renewed sheet-making. In the specialist world, the opinion is held that fibres which have already been milled once should not be milled any more (J Lumiainen, Refining of Recycled Fibre - Advantages and Disadvantages, Papermakers Conference, 187, (1992)). Attempts to solve this problem have been made using special milling techniques and by the addition of auxiliary materials which are uncommon in paper. These auxiliary materials are supposed to increase the strength of the paper, among other features.
The invention has as its object the further development of the conventional process for paper-making, in order to allow the preparation of paper with a higher strength without the use of conventional auxiliary materials, whereby the milling time should be as short as possible.
The process according to the invention for~ the preparation of paper commences with a process in which an aqueous suspension of comminuted cellulose material, for example half-stuff, is mechanically treated and is then subjected to a sheet-making process, characterised in that, the mechanical treatment is carried out in the presence of a tertiary amine-oxide. The mechanical treatment is preferably carried out in a refiner.
Tertiary amine-oxides are known to be alternative solvents for cellulose.
From US-PS 2 179 181 for example it is known that tertiary amine-oxides have the property of dissolving cellulose without converting it into derivatives, and that cellulose mouldings such as fibres can be obtained from these solutions by precipitation. In US-PS 3 447 939, US-PS 3 447 956 and US-PS 3 508 941 further processes for the preparation of cellulose solutions - 21~7276 are described whereby the solvents used are preferably cyclic amine-oxides.
In all these processes however cellulose is physically dissolved at elevated temperatu res.
It has been shown that with the process according to the invention, even waste paper can be added to the cellulose material, for example cellulose, and that even then the strength of the resulting paper is high. In this way therefore ~ste~r can be reused in the process according to the invention. It is known that ~ste ~ or cellulose fibres which have been recycled many times are not very suitable for renewed sheet-making. The given embodiment of the process according to the invention is based on the finding that comminuted ~ste ~:., which is subjected to a renewed milling process in the presence of a tertiary amine-oxide together with another cellulose material, is very suitable for use in the preparation of a high-grade paper.
A preferred embodiment of the process according to the invention consists of N-methylmorpholine-N-oxide being used as the tertiary amine-oxide.
The best concentration of tertiary amine-oxide in the aqueous phase of the suspension is between 55 and 72 wt%.
The invention further concerns the use of a tertiary amine-oxide as an auxiliary material in the mechanical treatment of comminuted material containing cellulose for the preparation of paper. The use of N-methyl-morpholine-N-oxide has proved to be especially advantageous.
The invention is further described by the following Examples.
Examples In order to reveal the effect of tertiary amine-oxides, cellulose from both sulphate and sulphite wood pulping processes were subjected to a standardised milling treatment at room temperature, in accordance with DIN 54 360 (November 1977) of the Standards Committee for Paper and Cardboard of the German Institute for Standards (registered Society). The reason for such milling treatment is to set standards for assessing the strength properties of the cellulose.
This is only possible when test sheets are prepared under given and reproducible conditions, and their strength properties are measured.
In accordance with the process described in DIN 54 360, suspensions of prehydrolysed sulphate cellulose ('Buckeye V5 high-grade pulp'), a sulphite-cellulose (beechwood digested-cellulose) and another beechwood digested-cellulose which had been mechanically premilled (sieve size 350 llm) were milledin a Jokro mill to varying SR degrees, whereby the consistency of the suspensions was standardised at 12%. These celluloses are not classical celluloses for paper-making; they were chosen so that the beneficial effects of amine-oxide could be better demonstrated. Using classical paper celluloses, still better effects would have been achieved without exception.
Not only water but also an aqueous solution of NMMO (60 wt% NMMO, 40 wt%
water) was used as the suspension medium in every test.
Sheet-making, using the respective cellulose suspensions which were obtained, was carried out according to DIN 54 358 T1 (February 1981). Strength testing (tear length) of the sheets obtained was carried out according to the standardised process described in DIN 53 112 (October 1981). The results are g i ven i n th e fol low i n g Tab l es.
Table 1: Pre-hydrolysed sulphate-cellulose (Southern pine, Buckeye V5, Proctor & Gamble) Milling time (min) 10 20 30 Suspension medium - water Milling degree ( SR): 8 9 10 Tear length (m): 700 800 1000 Suspension medium - 60% NMMO, 40% water Milling degree ( SR): 10 11 12 Tear length (m): 900 1300 1500 - 21~7276 Table 2: Sulphite cellulose tBeechwood, Lenzing) Milling time (min) 10 20 30 Suspension med i um - water Milling degree ( SR): 32 42 47 Tear length (m): 1800 2100 2500 Suspension medium - 60% NMMO, 40% water Milling degree ( SR): 37 47 54 Tear length (m): 2100 2500 3100 Table 3: Sulphite cellulose (premilled) (BKZ premilled, Lenzing) Milling time (min) 10 20 30 Suspension medium - water Milling degree ( SR): 51 63 72 Tear length (m): 1100 1700 1600 Suspension medium - 60% NMMO, 40% water Milling degree ( SR): 57 67 67 Tear length (m): 1400 1600 1900 It can be seen from all the Tables that the tear length of a given paper increases with increasing milling time, and that in every case the presence of NMMO gives the paper a greater tear length. This effect is especially marked with prehydrolysed sulphate-cellulose (see Table 1) where the presence of NMMO during milling of the cellulose fibres increases the tear length of the paper obtained by up to 50%.
It can also be seen from all the Tables that the presence of NMMO leads to more efficient milling because higher degrees of milling are attained in a shorter period of time. This is naturally reflected in a saving of energy.
It is astonishing that the increase in the degree of milling is not proportionalto the tear length. Thus for example, the presence of NMMO during the 30 minute milling of prehydrolysed sulphate-cellulose effects a 20% increase in the degree of milling but a 50% increase in the tear length.
It can also be seen that the premilled sulphite-cellulose (Table 3), which on account of its poor fibre-forming properties after 30 minutes milling gives a paper with a tear length of only 1600 m, gives with the addition of NMMO
a higher quality paper with a tear length of 1900 m; this latter paper is comparable with a paper prepared from a higher grade sulphite-cellulose (Table 2) using a suspension milled for 10 minutes without the addition of NMMO. This means that a material which can be processed by conventional means to give only a low grade paper, can be processed to give a high quality paper by milling in the presence of NMMO.
The process according to the invention is suitable for all types of cellulose and is independent of the chosen digestion process.
With the process according to the invention moreover, even waste paper consisting of fibres which have already been subjected several times to a conventional milling process and to sheet-making, can be processed together with cellulose to give high quality paper without additional auxiliary materialshaving to be added.
- 21~7276 SUMMARY
Process for the preparation of paper in which an aqueous suspension of comminuted cellulose material is mechanically treated and is subsequently subjected to a sheet-making process, characterised in that, the suspension contains a tertiary amine-oxide. The comminuted cellulose material can come partly from waste paper.
The current invention concerns a process for the preparation of paper in which an aqueous suspension of comminuted cellulose material is mechanically treated and is subjected to a sheet-making process.
It is known that cellulose which is to be processed into paper must be milled before sheet-making. According to DIN 54 360 (November 1977), milling means mechanical treatment of the cellulose in a suspended state during which its physical properties are so changed that it becomes suitable for the preparation of paper. During the milling of the slurry formed by the cellulose fibres and water, the fibres become cut, fibrillated and swollen.
Fibrillation means the splitting of the fibres parallel to the fibre axis. Aftermilling, the greater part of the fibrils remains hanging like frills on the fibres. Swelling and fibrillation are of great importance in the preparation of stron g paper.
The milling process is an energy-intensive process. Among products needing highly-milled fibrous materials, the milling of cellulose is indeed one of the most energy-intensive processes in paper-making. Polymeric saccharides, monomeric and polymeric amines, amides and dyestuffs are recommended as milling aids (M Milichovsky, Chemische Aspekte der Mahlung von Zellstoff:
Zellstoff und Papier, 38, page 17, (1989)). The degree of milling is given in degrees Schopper-Riegler (SR). The strength of the resulting paper generally increases as the degree of milling increases.
Machines such as for instance, Hollander beaters, Jordan mills, refiners, disc mills and pulpers can be used for milling. The stock slurry is processed between a moving part and a fixed part of the machine during the milling process (Handbuch der Papier- und Pappenfabrikation, (Papierlexikon), 2nd Edition, Vol II, L-Z, 1971).
It is moreover known that the strength of a paper can be further increased with additives. Such materials are for example natural rubbers and carboxymethyl cellulose. It is also known from US-A 3 447 956 that paper which has had chemical treatment, wherein it is swollen at a temperature - ~147276 above 100 C in a molten tertiary amine-oxide, has a higher strength.
In US-A 3 503 700 it is said that paper which is soaked in a 25% aqueous solution of a tertiary amine-oxide, dried and heated to above 200tand then cooled and rinsed with water to wash out the tertiary amine-oxide again, has a higher strength after such treatment.
On the other hand problems which occur in the processing of ~steE~per are increasingly described in the literature. A phenomenon well known to the paper-maker is that cellulose fibres which have already been used one or more times for paper-making are no longer very suitable for renewed sheet-making. In the specialist world, the opinion is held that fibres which have already been milled once should not be milled any more (J Lumiainen, Refining of Recycled Fibre - Advantages and Disadvantages, Papermakers Conference, 187, (1992)). Attempts to solve this problem have been made using special milling techniques and by the addition of auxiliary materials which are uncommon in paper. These auxiliary materials are supposed to increase the strength of the paper, among other features.
The invention has as its object the further development of the conventional process for paper-making, in order to allow the preparation of paper with a higher strength without the use of conventional auxiliary materials, whereby the milling time should be as short as possible.
The process according to the invention for~ the preparation of paper commences with a process in which an aqueous suspension of comminuted cellulose material, for example half-stuff, is mechanically treated and is then subjected to a sheet-making process, characterised in that, the mechanical treatment is carried out in the presence of a tertiary amine-oxide. The mechanical treatment is preferably carried out in a refiner.
Tertiary amine-oxides are known to be alternative solvents for cellulose.
From US-PS 2 179 181 for example it is known that tertiary amine-oxides have the property of dissolving cellulose without converting it into derivatives, and that cellulose mouldings such as fibres can be obtained from these solutions by precipitation. In US-PS 3 447 939, US-PS 3 447 956 and US-PS 3 508 941 further processes for the preparation of cellulose solutions - 21~7276 are described whereby the solvents used are preferably cyclic amine-oxides.
In all these processes however cellulose is physically dissolved at elevated temperatu res.
It has been shown that with the process according to the invention, even waste paper can be added to the cellulose material, for example cellulose, and that even then the strength of the resulting paper is high. In this way therefore ~ste~r can be reused in the process according to the invention. It is known that ~ste ~ or cellulose fibres which have been recycled many times are not very suitable for renewed sheet-making. The given embodiment of the process according to the invention is based on the finding that comminuted ~ste ~:., which is subjected to a renewed milling process in the presence of a tertiary amine-oxide together with another cellulose material, is very suitable for use in the preparation of a high-grade paper.
A preferred embodiment of the process according to the invention consists of N-methylmorpholine-N-oxide being used as the tertiary amine-oxide.
The best concentration of tertiary amine-oxide in the aqueous phase of the suspension is between 55 and 72 wt%.
The invention further concerns the use of a tertiary amine-oxide as an auxiliary material in the mechanical treatment of comminuted material containing cellulose for the preparation of paper. The use of N-methyl-morpholine-N-oxide has proved to be especially advantageous.
The invention is further described by the following Examples.
Examples In order to reveal the effect of tertiary amine-oxides, cellulose from both sulphate and sulphite wood pulping processes were subjected to a standardised milling treatment at room temperature, in accordance with DIN 54 360 (November 1977) of the Standards Committee for Paper and Cardboard of the German Institute for Standards (registered Society). The reason for such milling treatment is to set standards for assessing the strength properties of the cellulose.
This is only possible when test sheets are prepared under given and reproducible conditions, and their strength properties are measured.
In accordance with the process described in DIN 54 360, suspensions of prehydrolysed sulphate cellulose ('Buckeye V5 high-grade pulp'), a sulphite-cellulose (beechwood digested-cellulose) and another beechwood digested-cellulose which had been mechanically premilled (sieve size 350 llm) were milledin a Jokro mill to varying SR degrees, whereby the consistency of the suspensions was standardised at 12%. These celluloses are not classical celluloses for paper-making; they were chosen so that the beneficial effects of amine-oxide could be better demonstrated. Using classical paper celluloses, still better effects would have been achieved without exception.
Not only water but also an aqueous solution of NMMO (60 wt% NMMO, 40 wt%
water) was used as the suspension medium in every test.
Sheet-making, using the respective cellulose suspensions which were obtained, was carried out according to DIN 54 358 T1 (February 1981). Strength testing (tear length) of the sheets obtained was carried out according to the standardised process described in DIN 53 112 (October 1981). The results are g i ven i n th e fol low i n g Tab l es.
Table 1: Pre-hydrolysed sulphate-cellulose (Southern pine, Buckeye V5, Proctor & Gamble) Milling time (min) 10 20 30 Suspension medium - water Milling degree ( SR): 8 9 10 Tear length (m): 700 800 1000 Suspension medium - 60% NMMO, 40% water Milling degree ( SR): 10 11 12 Tear length (m): 900 1300 1500 - 21~7276 Table 2: Sulphite cellulose tBeechwood, Lenzing) Milling time (min) 10 20 30 Suspension med i um - water Milling degree ( SR): 32 42 47 Tear length (m): 1800 2100 2500 Suspension medium - 60% NMMO, 40% water Milling degree ( SR): 37 47 54 Tear length (m): 2100 2500 3100 Table 3: Sulphite cellulose (premilled) (BKZ premilled, Lenzing) Milling time (min) 10 20 30 Suspension medium - water Milling degree ( SR): 51 63 72 Tear length (m): 1100 1700 1600 Suspension medium - 60% NMMO, 40% water Milling degree ( SR): 57 67 67 Tear length (m): 1400 1600 1900 It can be seen from all the Tables that the tear length of a given paper increases with increasing milling time, and that in every case the presence of NMMO gives the paper a greater tear length. This effect is especially marked with prehydrolysed sulphate-cellulose (see Table 1) where the presence of NMMO during milling of the cellulose fibres increases the tear length of the paper obtained by up to 50%.
It can also be seen from all the Tables that the presence of NMMO leads to more efficient milling because higher degrees of milling are attained in a shorter period of time. This is naturally reflected in a saving of energy.
It is astonishing that the increase in the degree of milling is not proportionalto the tear length. Thus for example, the presence of NMMO during the 30 minute milling of prehydrolysed sulphate-cellulose effects a 20% increase in the degree of milling but a 50% increase in the tear length.
It can also be seen that the premilled sulphite-cellulose (Table 3), which on account of its poor fibre-forming properties after 30 minutes milling gives a paper with a tear length of only 1600 m, gives with the addition of NMMO
a higher quality paper with a tear length of 1900 m; this latter paper is comparable with a paper prepared from a higher grade sulphite-cellulose (Table 2) using a suspension milled for 10 minutes without the addition of NMMO. This means that a material which can be processed by conventional means to give only a low grade paper, can be processed to give a high quality paper by milling in the presence of NMMO.
The process according to the invention is suitable for all types of cellulose and is independent of the chosen digestion process.
With the process according to the invention moreover, even waste paper consisting of fibres which have already been subjected several times to a conventional milling process and to sheet-making, can be processed together with cellulose to give high quality paper without additional auxiliary materialshaving to be added.
- 21~7276 SUMMARY
Process for the preparation of paper in which an aqueous suspension of comminuted cellulose material is mechanically treated and is subsequently subjected to a sheet-making process, characterised in that, the suspension contains a tertiary amine-oxide. The comminuted cellulose material can come partly from waste paper.
Claims (8)
1. Process for the preparation of paper in which an aqueous suspension of comminuted cellulose material is mechanically treated and is then subjected to a sheet-making process, characterised in that, the mechanical treatment is carried out in the presence of a tertiary amine-oxide.
2. Process in accordance with Claim 1, characterised in that, as the comminuted cellulose material a material is used which has already been subjected once to a sheet-making process.
3. Process in accordance with Claim 2, characterised in that, the cellulose material used comes partly from waste paper.
4. Process in accordance with one or more of the Claims 1 to 3, characterised in that, N-methylmorpholine-N-oxide is used as the tertiary amine-oxide.
5. Process in accordance with one or more of the Claims 1 to 4, characterised in that, the aqueous phase of the suspension contains from 55 to 72 wt% of the tertiary amine-oxide.
6. Process in accordance with one or more of the Claims 1 to 5, characterised in that, the mechanical treatment is carried out in a refiner.
7. Use of a tertiary amine-oxide as an auxiliary material in the mechanical treatment of comminuted cellulose material in the preparation of paper.
8. Use of N-morpholine-N-oxide as an auxiliary material in the mechanical treatment of comminuted cellulose material in the preparation of paper.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ATA1791/93 | 1993-09-06 | ||
AT0179193A AT401072B (en) | 1993-09-06 | 1993-09-06 | METHOD FOR PRODUCING PAPER |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2147276A1 true CA2147276A1 (en) | 1995-03-16 |
Family
ID=3521055
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002147276A Abandoned CA2147276A1 (en) | 1993-09-06 | 1994-07-27 | Papermaking process |
Country Status (14)
Country | Link |
---|---|
EP (1) | EP0670926B1 (en) |
AT (2) | AT401072B (en) |
AU (1) | AU683074B2 (en) |
BR (1) | BR9405577A (en) |
CA (1) | CA2147276A1 (en) |
DE (2) | DE59400174D1 (en) |
DK (1) | DK0670926T3 (en) |
ES (1) | ES2087000T3 (en) |
FI (1) | FI952161A (en) |
GB (1) | GB2286606B (en) |
GR (1) | GR3019611T3 (en) |
NO (1) | NO951708L (en) |
SI (1) | SI0670926T1 (en) |
WO (1) | WO1995007386A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6001218A (en) | 1994-06-29 | 1999-12-14 | Kimberly-Clark Worldwide, Inc. | Production of soft paper products from old newspaper |
US6027610A (en) | 1994-06-29 | 2000-02-22 | Kimberly-Clark Corporation | Production of soft paper products from old newspaper |
US6074527A (en) | 1994-06-29 | 2000-06-13 | Kimberly-Clark Worldwide, Inc. | Production of soft paper products from coarse cellulosic fibers |
US6296736B1 (en) | 1997-10-30 | 2001-10-02 | Kimberly-Clark Worldwide, Inc. | Process for modifying pulp from recycled newspapers |
US6387210B1 (en) | 1998-09-30 | 2002-05-14 | Kimberly-Clark Worldwide, Inc. | Method of making sanitary paper product from coarse fibers |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6042890A (en) * | 1997-02-25 | 2000-03-28 | Lenzing Aktiengesellschaft | Process for producing a strengthened fiber assembly |
AT404368B (en) * | 1997-02-25 | 1998-11-25 | Chemiefaser Lenzing Ag | METHOD FOR PRODUCING A FASTENED FIBER COMPOSITE |
WO2008119770A1 (en) * | 2007-03-30 | 2008-10-09 | Basf Se | Method for modifying the structure of a cellulose material by treatment with an ionic liquid |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3237574A1 (en) * | 1982-10-09 | 1984-04-12 | Hoechst Ag, 6230 Frankfurt | Use of amine oxides in the pulp and paper manufacture |
-
1993
- 1993-09-06 AT AT0179193A patent/AT401072B/en not_active IP Right Cessation
-
1994
- 1994-07-27 SI SI9430003T patent/SI0670926T1/xx unknown
- 1994-07-27 DE DE59400174T patent/DE59400174D1/en not_active Expired - Fee Related
- 1994-07-27 AT AT94921526T patent/ATE136077T1/en not_active IP Right Cessation
- 1994-07-27 WO PCT/AT1994/000098 patent/WO1995007386A1/en active IP Right Grant
- 1994-07-27 DK DK94921526.3T patent/DK0670926T3/en active
- 1994-07-27 EP EP94921526A patent/EP0670926B1/en not_active Expired - Lifetime
- 1994-07-27 GB GB9508002A patent/GB2286606B/en not_active Expired - Fee Related
- 1994-07-27 CA CA002147276A patent/CA2147276A1/en not_active Abandoned
- 1994-07-27 BR BR9405577-7A patent/BR9405577A/en not_active Application Discontinuation
- 1994-07-27 ES ES94921526T patent/ES2087000T3/en not_active Expired - Lifetime
- 1994-07-27 AU AU72220/94A patent/AU683074B2/en not_active Ceased
- 1994-07-27 DE DE4496602T patent/DE4496602D2/en not_active Expired - Fee Related
-
1995
- 1995-05-03 NO NO951708A patent/NO951708L/en unknown
- 1995-05-05 FI FI952161A patent/FI952161A/en unknown
-
1996
- 1996-04-09 GR GR960401006T patent/GR3019611T3/en unknown
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6001218A (en) | 1994-06-29 | 1999-12-14 | Kimberly-Clark Worldwide, Inc. | Production of soft paper products from old newspaper |
US6027610A (en) | 1994-06-29 | 2000-02-22 | Kimberly-Clark Corporation | Production of soft paper products from old newspaper |
US6074527A (en) | 1994-06-29 | 2000-06-13 | Kimberly-Clark Worldwide, Inc. | Production of soft paper products from coarse cellulosic fibers |
US6296736B1 (en) | 1997-10-30 | 2001-10-02 | Kimberly-Clark Worldwide, Inc. | Process for modifying pulp from recycled newspapers |
US6387210B1 (en) | 1998-09-30 | 2002-05-14 | Kimberly-Clark Worldwide, Inc. | Method of making sanitary paper product from coarse fibers |
Also Published As
Publication number | Publication date |
---|---|
NO951708D0 (en) | 1995-05-03 |
WO1995007386A1 (en) | 1995-03-16 |
FI952161A0 (en) | 1995-05-05 |
ATE136077T1 (en) | 1996-04-15 |
EP0670926A1 (en) | 1995-09-13 |
ES2087000T3 (en) | 1996-07-01 |
GR3019611T3 (en) | 1996-07-31 |
AU7222094A (en) | 1995-03-27 |
AU683074B2 (en) | 1997-10-30 |
GB9508002D0 (en) | 1995-06-07 |
EP0670926B1 (en) | 1996-03-27 |
AT401072B (en) | 1996-06-25 |
GB2286606A (en) | 1995-08-23 |
SI0670926T1 (en) | 1997-10-31 |
DK0670926T3 (en) | 1996-07-29 |
NO951708L (en) | 1995-05-03 |
FI952161A (en) | 1995-05-05 |
DE4496602D2 (en) | 1995-09-21 |
GB2286606B (en) | 1997-01-22 |
ATA179193A (en) | 1995-10-15 |
BR9405577A (en) | 1999-09-08 |
DE59400174D1 (en) | 1996-05-02 |
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