EP0285227A1 - A process for preserving paper sheets or webs and a device for carrying out that process - Google Patents
A process for preserving paper sheets or webs and a device for carrying out that process Download PDFInfo
- Publication number
- EP0285227A1 EP0285227A1 EP88200608A EP88200608A EP0285227A1 EP 0285227 A1 EP0285227 A1 EP 0285227A1 EP 88200608 A EP88200608 A EP 88200608A EP 88200608 A EP88200608 A EP 88200608A EP 0285227 A1 EP0285227 A1 EP 0285227A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- paper
- solution
- agent
- liquid
- amount
- 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.)
- Granted
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H25/00—After-treatment of paper not provided for in groups D21H17/00 - D21H23/00
- D21H25/18—After-treatment of paper not provided for in groups D21H17/00 - D21H23/00 of old paper as in books, documents, e.g. restoring
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
- D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
- D21H21/18—Reinforcing agents
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
- D21H23/22—Addition to the formed paper
- D21H23/32—Addition to the formed paper by contacting paper with an excess of material, e.g. from a reservoir or in a manner necessitating removal of applied excess material from the paper
- D21H23/42—Paper being at least partly surrounded by the material on both sides
Definitions
- This invention relates to a process for preserving paper sheets or webs and to a device for carrying out that process.
- US patent 3,676,182 discloses a process for treating paper sheets or webs throughout their thickness with a solution of a deacidification agent in an organic solvent or in a mixture of organic solvents and then drying same.
- the object of this known treatment is to neutralize the acid components contained in the paper and thereby to render the paper more resistant to prolonged storage in archives.
- a polymeric strengthening agent for the paper can be included in the solution.
- the use of an organic liquid medium instead of an aqueous medium has the advantage that more rapid drying can be obtained while the time of contact with the printed matter present on the paper can be kept so short that this printed matter sustains no visible damage owing to the treatment conducted.
- the paper can be impregnated or sprayed with the solution and then be dried.
- US patent 3,939,091 also discloses a liquid mixture on the basis of organic solvents designed for deacidifying paper.
- the employed agent effecting deacidification or, in other words, providing an alkaline component is methoxy magnesium methyl carbonate, called in the patent methyl magnesium carbonate.
- this invention is characterized in that a solution of a deacidification agent and of a polymeric strengthening agent for the paper in an organic solvent or in a mixture of organic solvents is sprayed onto one surface of the paper, and that a strong sucking action is exerted on the other surface of the paper so as to draw the solution through the entire thickness of the paper and also dry the treated paper at least partly.
- the process now claimed offers a number of important advantages: the solution can be more uniformly distributed throughout the thickness of the paper; the amount of solution can be more optimally dosed; and the process can be carried out more rapidly, partly because subsequent drying usually need not take place.
- the process claimed leads to an excellent total preservation and is eminently suited for the mass preservation of archives and library material which threatens to be lost forever without a timely appropriate treatment.
- Suitable polymeric strengthening agents for use in the present solution are known per se adhesives for fibrous materials of cellulose or derivatives thereof.
- Suitable strengthening agents may be cellulose or starch ethers, such as hydroxyethyl cellulose and preferably hydroxypropyl cellulose.
- the latter product is sold by Hercules Powder Company under the name of Klucel L in the form of fine granules.
- the amount in which the strengthening agent is used is as a rule 5-40 g and preferably 5-30 g/l solution.
- the polymeric strengthening agent be present in the solution in the dissolved state. This is in fact necessary to obtain a uniform distribution of the strengthening agent throughout the thickness of the paper to be treated. If the strengthening agent were not dissolved, it would only be deposited on and near the paper surface, so it would not be able to penetrate into the interior of the paper material so that more damage than advantage would be caused to the material to be preserved which is very vulnerable as it is. So when selecting the polymeric strengthening agent and the solvent or the solvents therefor, but also when selecting the other constituents and their mutual ratios, one should always bear in mind that the final preserving liquid has to be a real solution.
- a suitable agent for preventing disintegration or decay of the polymeric strengthening agent is also dissolved in the treatment solution.
- agents may be bactericides and fungicides as well as agents for preventing enzymatic decomposition of the strengthening agent.
- Thymol is an example of a suitable agent preventing the development of bacteria and fungi in the case of using a cellulose ether as the polymeric strengthening agent. As a rule only a minor amount of such an agent is added against disintegration or decay.
- deacidification agents to be used in the present solution are to be found in US patents 3,676,182 and 3,939,091 discussed above.
- inorganic deacidification agents are used, and the following compounds may be mentioned as examples thereof: magnesium methoxide, magnesium methyl carbonate, magnesium ethyl carbonate, methoxy magnesium methyl carbonate, and ethoxy magnesium ethyl carbonate.
- methoxy magnesium methyl carbonate has proved to be eminently suitable.
- the deacidification agent is usually employed in an amount of 0.7-2.5 g and preferably of 1.0-2.0 g/l solution.
- Such a concentration is sufficient to adjust the pH of the paper to a value of 8-8.5 and further to provide a sufficient additional amount to ensure a prolonged buffer effect at that pH.
- a number of the above-mentioned inorganic deacidification agents is commercially available, usually in the form of a solution in a lower alcohol or in a mixture of a lower alcohol and a chlorofluorohydrocarbon.
- Methanol is a very suitable solvent, either alone or even better in combination with one or several other solvents which, for instance, may be selected from aliphatic or aromatic hydrocarbons, halogenated hydrocarbons, ethers, esters and ketones.
- a mixture of a major amount of methanol and a minor amount of acetone has proved to be very suitable, especially a mixture of methanol and acetone in a volume ratio of about 4/1.
- the present preserving liquid can be easily prepared by combining the different components in the appropriate amounts and, if required, stirring same with moderate heating until the solids have dissolved.
- the deacidification agent is then mostly added in the form of a concentrated solution in an organic solvent. If necessary, the resulting solution may be filtered to remove all the undissolved residues.
- the preserving liquid may also be prepared in the form of a concentrate diluted for use as far as necessary. Both the concentrate and the ready-for-use preserving liquid are very stable and can be stored for extended periods of time.
- a formulation of a ready-for-use preserving liquid with which excellent results have been obtained has the following composition: -methanol 78 vol.% -acetone 20 vol.% -methoxy magnesium methyl carbonate (0.5 M in methanol) 2 vol.% -Klucel L (hydroxypropyl cellulose from Hercules Powder Co.) 2 wt.% -thymol 0.2 wt.%
- the preserving liquid is applied by spraying to one surface of the paper sheet or web and a strong sucking action is exerted on the other surface of the paper.
- the paper is supported by a carrier allowing the passage of liquid, and the liquid is sprayed onto the free paper surface while a strong sucking action is exerted through the supporting carrier so that the paper is uniformly impregnated with the liquid throughout its thickness and is also at least partly dried. If necessary, further drying can be effected by suction drying for an extended period of time or by using any mild drying technique, e.g., with a hot air stream.
- the amount of preserving liquid to be applied depends on different factors, such as the nature, condition and thickness of the paper. On the average, however, it has turned out that excellent preservation is obtainable with an amount of preserving liquid of 0.2-0.5 g/dm2 paper area.
- This invention also relates to a device for carrying out the above described preservation of paper sheets or webs.
- This device is characterized in that it contains a treatment chamber provided in the lower part with a paper feed opening in one end wall and with a paper discharge opening in the opposite end wall, with a suction receptacle being arranged between the feed and discharge openings and comprising at the top a large number of perforations, there being provided a conveyor belt allowing the passage of liquid, which conveyor belt is capable of moving around the suction receptacle and is positioned against the top thereof, at least one liquid sprayer being present in the upper part of the treatment chamber near the feed opening.
- the treatment chamber proper may be composed of aluminum sections with aluminum sheeting and with one side wall in the direction of transport consisting of a transparent material, such as a polycarbonate sheet, so that the progress of the treatment may be monitored.
- the treatment chamber may be placed as a superstructure on a substructure, and the latter can be utilized to accommodate the operating and auxiliary mechanisms, such as an electronic and pneumatic control unit, a storage tank for the preserving liquid, a pressure bottle containing propellant gas (e.g., CO2), a compressor, an exhaust fan, a motor, the required conduits and connecting pieces etc.
- propellant gas e.g., CO2
- a slot for inserting the paper to be treated is provided at the feed end of the treatment chamber.
- a sensor which may be provided near that feed end will transmit a signal which causes the liquid sprayer(s) to function.
- the sensor in question can stop the spraying of liquid by means of a signal.
- Also provided near the feed opening may be sensors recording the thickness, nature and/or sizes of the paper inserted and transmitting, as a function thereof, signals controlling the speed of the conveyor belt, the amount of spray liquid and/or the area of the surface to be sprayed.
- the paper comes to rest on a conveyor belt which is capable of moving around a suction receptacle in the lower part of the treatment chamber and is positioned against the perforated top of the suction receptacle.
- At least one liquid sprayer for atomizing the preserving liquid in the direction of the conveyor belt.
- two liquid sprayers are present, and preferably, both the height and the width of the liquid sprayer(s) are adjustable so as to exactly control the area to be sprayed. This can be effected automatically by means of a sensor near the feed opening, as stated before.
- the suction receptacle is provided, e.g., in a side wall in the direction of transport, with a plurality of suction nozzles, e.g., three, which ensure a proper suction and exhaustion during the entire transport throughout suction and exhaustion during the entire transport through the treatment chamber.
- the preserving liquid is thereby uniformly distributed throughout the thickness of the paper to be treated, and the paper is also at least partly and usually even completely dried. This can be carried out by a skilled worker in a rather simple and precise way.
- the exhausted vapours can be collected and processed further.
- the conveyor belt may be a woven endless belt. Anyhow, it must allow the passage of liquid, and preferably it is of the self-discharging type, which means that the fine openings present in the direction of thickness of that belt are larger at the side facing the top of the suction receptacle than at the side for conveying paper, which prevents that belt from becoming easily clogged owing to solids from the preserving liquid sucked in.
- the size of the treatment chamber in the direction of transport is preferably selected so that the distance to be traversed is sufficient to dry the treated paper. If required, however, the part of the treatment chamber closer to the discharge opening may comprise means for carrying out an additional thermal drying treatment. Such means may be means for effecting a hot air stream or infrared radiation.
- the treatment chamber is provided with a discharge slot at the end of the conveyor belt.
- the treated paper discharged through that slot can be collected in a collecting receptacle.
Landscapes
- Paper (AREA)
Abstract
Description
- This invention relates to a process for preserving paper sheets or webs and to a device for carrying out that process.
- US patent 3,676,182 discloses a process for treating paper sheets or webs throughout their thickness with a solution of a deacidification agent in an organic solvent or in a mixture of organic solvents and then drying same. The object of this known treatment is to neutralize the acid components contained in the paper and thereby to render the paper more resistant to prolonged storage in archives. Moreover, a polymeric strengthening agent for the paper can be included in the solution. The use of an organic liquid medium instead of an aqueous medium has the advantage that more rapid drying can be obtained while the time of contact with the printed matter present on the paper can be kept so short that this printed matter sustains no visible damage owing to the treatment conducted. The paper can be impregnated or sprayed with the solution and then be dried.
- US patent 3,939,091 also discloses a liquid mixture on the basis of organic solvents designed for deacidifying paper. In this known mixture the employed agent effecting deacidification or, in other words, providing an alkaline component is methoxy magnesium methyl carbonate, called in the patent methyl magnesium carbonate.
- There has now been found a simple, efficient and inexpensive method of simultaneously deacidifying, strengthening, and at least partly drying paper sheets or webs.
- Accordingly, this invention is characterized in that a solution of a deacidification agent and of a polymeric strengthening agent for the paper in an organic solvent or in a mixture of organic solvents is sprayed onto one surface of the paper, and that a strong sucking action is exerted on the other surface of the paper so as to draw the solution through the entire thickness of the paper and also dry the treated paper at least partly.
- As compared with the prior art, the process now claimed offers a number of important advantages: the solution can be more uniformly distributed throughout the thickness of the paper; the amount of solution can be more optimally dosed; and the process can be carried out more rapidly, partly because subsequent drying usually need not take place. The process claimed leads to an excellent total preservation and is eminently suited for the mass preservation of archives and library material which threatens to be lost forever without a timely appropriate treatment.
- Suitable polymeric strengthening agents for use in the present solution are known per se adhesives for fibrous materials of cellulose or derivatives thereof. Suitable strengthening agents may be cellulose or starch ethers, such as hydroxyethyl cellulose and preferably hydroxypropyl cellulose. The latter product is sold by Hercules Powder Company under the name of Klucel L in the form of fine granules. The amount in which the strengthening agent is used is as a rule 5-40 g and preferably 5-30 g/l solution.
- It is of essential importance that the polymeric strengthening agent be present in the solution in the dissolved state. This is in fact necessary to obtain a uniform distribution of the strengthening agent throughout the thickness of the paper to be treated. If the strengthening agent were not dissolved, it would only be deposited on and near the paper surface, so it would not be able to penetrate into the interior of the paper material so that more damage than advantage would be caused to the material to be preserved which is very vulnerable as it is. So when selecting the polymeric strengthening agent and the solvent or the solvents therefor, but also when selecting the other constituents and their mutual ratios, one should always bear in mind that the final preserving liquid has to be a real solution.
- Preferably, a suitable agent for preventing disintegration or decay of the polymeric strengthening agent is also dissolved in the treatment solution. Such agents may be bactericides and fungicides as well as agents for preventing enzymatic decomposition of the strengthening agent. Thymol is an example of a suitable agent preventing the development of bacteria and fungi in the case of using a cellulose ether as the polymeric strengthening agent. As a rule only a minor amount of such an agent is added against disintegration or decay.
- Suitable examples of deacidification agents to be used in the present solution are to be found in US patents 3,676,182 and 3,939,091 discussed above. Preferably, inorganic deacidification agents are used, and the following compounds may be mentioned as examples thereof: magnesium methoxide, magnesium methyl carbonate, magnesium ethyl carbonate, methoxy magnesium methyl carbonate, and ethoxy magnesium ethyl carbonate. In particular, methoxy magnesium methyl carbonate has proved to be eminently suitable. The deacidification agent is usually employed in an amount of 0.7-2.5 g and preferably of 1.0-2.0 g/l solution. Such a concentration is sufficient to adjust the pH of the paper to a value of 8-8.5 and further to provide a sufficient additional amount to ensure a prolonged buffer effect at that pH. A number of the above-mentioned inorganic deacidification agents is commercially available, usually in the form of a solution in a lower alcohol or in a mixture of a lower alcohol and a chlorofluorohydrocarbon.
- The selection of a suitable organic solvent or mixture of organic solvents is very important, since, as stated before, all the components of the preserving liquid must dissolve therein. Methanol is a very suitable solvent, either alone or even better in combination with one or several other solvents which, for instance, may be selected from aliphatic or aromatic hydrocarbons, halogenated hydrocarbons, ethers, esters and ketones. A mixture of a major amount of methanol and a minor amount of acetone has proved to be very suitable, especially a mixture of methanol and acetone in a volume ratio of about 4/1.
- The present preserving liquid can be easily prepared by combining the different components in the appropriate amounts and, if required, stirring same with moderate heating until the solids have dissolved. The deacidification agent is then mostly added in the form of a concentrated solution in an organic solvent. If necessary, the resulting solution may be filtered to remove all the undissolved residues. The preserving liquid may also be prepared in the form of a concentrate diluted for use as far as necessary. Both the concentrate and the ready-for-use preserving liquid are very stable and can be stored for extended periods of time.
- A formulation of a ready-for-use preserving liquid with which excellent results have been obtained has the following composition:
-methanol 78 vol.%
-acetone 20 vol.%
-methoxy magnesium methyl carbonate (0.5 M in methanol) 2 vol.%
-Klucel L (hydroxypropyl cellulose from Hercules Powder Co.) 2 wt.%
-thymol 0.2 wt.% - The preserving liquid is applied by spraying to one surface of the paper sheet or web and a strong sucking action is exerted on the other surface of the paper. Preferably, the paper is supported by a carrier allowing the passage of liquid, and the liquid is sprayed onto the free paper surface while a strong sucking action is exerted through the supporting carrier so that the paper is uniformly impregnated with the liquid throughout its thickness and is also at least partly dried. If necessary, further drying can be effected by suction drying for an extended period of time or by using any mild drying technique, e.g., with a hot air stream. The amount of preserving liquid to be applied depends on different factors, such as the nature, condition and thickness of the paper. On the average, however, it has turned out that excellent preservation is obtainable with an amount of preserving liquid of 0.2-0.5 g/dm² paper area.
- This invention also relates to a device for carrying out the above described preservation of paper sheets or webs. This device is characterized in that it contains a treatment chamber provided in the lower part with a paper feed opening in one end wall and with a paper discharge opening in the opposite end wall, with a suction receptacle being arranged between the feed and discharge openings and comprising at the top a large number of perforations, there being provided a conveyor belt allowing the passage of liquid, which conveyor belt is capable of moving around the suction receptacle and is positioned against the top thereof, at least one liquid sprayer being present in the upper part of the treatment chamber near the feed opening.
- The treatment chamber proper may be composed of aluminum sections with aluminum sheeting and with one side wall in the direction of transport consisting of a transparent material, such as a polycarbonate sheet, so that the progress of the treatment may be monitored.
- The treatment chamber may be placed as a superstructure on a substructure, and the latter can be utilized to accommodate the operating and auxiliary mechanisms, such as an electronic and pneumatic control unit, a storage tank for the preserving liquid, a pressure bottle containing propellant gas (e.g., CO₂), a compressor, an exhaust fan, a motor, the required conduits and connecting pieces etc.
- A slot for inserting the paper to be treated is provided at the feed end of the treatment chamber. When paper is inserted, a sensor which may be provided near that feed end will transmit a signal which causes the liquid sprayer(s) to function. When paper is no longer inserted, the sensor in question can stop the spraying of liquid by means of a signal.
- Also provided near the feed opening may be sensors recording the thickness, nature and/or sizes of the paper inserted and transmitting, as a function thereof, signals controlling the speed of the conveyor belt, the amount of spray liquid and/or the area of the surface to be sprayed.
- Through the feed slot the paper comes to rest on a conveyor belt which is capable of moving around a suction receptacle in the lower part of the treatment chamber and is positioned against the perforated top of the suction receptacle.
- Provided in the upper part of the treatment chamber, near the feed opening, is at least one liquid sprayer for atomizing the preserving liquid in the direction of the conveyor belt. As a rule, two liquid sprayers are present, and preferably, both the height and the width of the liquid sprayer(s) are adjustable so as to exactly control the area to be sprayed. This can be effected automatically by means of a sensor near the feed opening, as stated before.
- The suction receptacle is provided, e.g., in a side wall in the direction of transport, with a plurality of suction nozzles, e.g., three, which ensure a proper suction and exhaustion during the entire transport throughout suction and exhaustion during the entire transport through the treatment chamber. The preserving liquid is thereby uniformly distributed throughout the thickness of the paper to be treated, and the paper is also at least partly and usually even completely dried. This can be carried out by a skilled worker in a rather simple and precise way. The exhausted vapours can be collected and processed further.
- The conveyor belt may be a woven endless belt. Anyhow, it must allow the passage of liquid, and preferably it is of the self-discharging type, which means that the fine openings present in the direction of thickness of that belt are larger at the side facing the top of the suction receptacle than at the side for conveying paper, which prevents that belt from becoming easily clogged owing to solids from the preserving liquid sucked in.
- The size of the treatment chamber in the direction of transport is preferably selected so that the distance to be traversed is sufficient to dry the treated paper. If required, however, the part of the treatment chamber closer to the discharge opening may comprise means for carrying out an additional thermal drying treatment. Such means may be means for effecting a hot air stream or infrared radiation.
- Finally, the treatment chamber is provided with a discharge slot at the end of the conveyor belt. The treated paper discharged through that slot can be collected in a collecting receptacle.
Claims (10)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL8700766 | 1987-04-01 | ||
NL8700766A NL8700766A (en) | 1987-04-01 | 1987-04-01 | METHOD FOR THE PRESERVATION OF SHEET OR PAPER PAPER AND LIQUID USED THEREIN AND DEVICE FOR EXPORTING THEREOF |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0285227A1 true EP0285227A1 (en) | 1988-10-05 |
EP0285227B1 EP0285227B1 (en) | 1992-11-25 |
Family
ID=19849794
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19880200608 Expired EP0285227B1 (en) | 1987-04-01 | 1988-03-31 | A process for preserving paper sheets or webs and a device for carrying out that process |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0285227B1 (en) |
DE (1) | DE3876121T2 (en) |
NL (1) | NL8700766A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5468706A (en) * | 1993-01-07 | 1995-11-21 | Huels Aktiengesellschaft | Storage-stable solution of a mixture of carbonated magnesium methoxide, carbonated magnesium ethoxide and their carbonated mixed alkoxide in a combination of methanol and ethanol and uses thereof |
US5468705A (en) * | 1993-01-07 | 1995-11-21 | Huels Aktiengesellschaft | Storage-stable solution of carbonated magnesium methoxide in methanol and its use |
EP3339508A1 (en) * | 2016-12-20 | 2018-06-27 | Nitrochemie Aschau GmbH | Process for the treatment of materials containing fibers |
LU93386B1 (en) * | 2016-12-20 | 2018-07-24 | Nitrochemie Gmbh | Process for processing materials containing fibers |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2633437A (en) * | 1951-07-31 | 1953-03-31 | Stoelting Bros Co | Method of washing aluminum kitchen utensils |
US3676182A (en) * | 1970-08-31 | 1972-07-11 | Richard Daniel Smith | Treatment of cellulosic materials |
DE2112997A1 (en) * | 1971-02-16 | 1972-09-28 | Heinz Goldbeck | Neutralisation of paper - with alkaline mist using ph measurements for process control |
FR2125963A5 (en) * | 1971-02-16 | 1972-09-29 | Knubben Franz | Regenerating paper prints - treating with alkaline solns to neutralise acidic formations in ageing paper |
US3862916A (en) * | 1973-02-05 | 1975-01-28 | World Patent Dev Corp | Solutions of polyvinyl acetals with phenolic antioxidant in preparation for restoring and/or preserving papers |
US3899439A (en) * | 1973-03-12 | 1975-08-12 | Hercules Inc | Method of preparing aqueous dispersions of hydroxypropyl cellulose |
US3939091A (en) * | 1975-02-14 | 1976-02-17 | The United States Of America As Represented By The Librarian Of Congress | Composition for use in deacidification of paper |
US3958586A (en) * | 1974-12-04 | 1976-05-25 | Tasope' Limited | Combined washer and dryer unit |
-
1987
- 1987-04-01 NL NL8700766A patent/NL8700766A/en not_active Application Discontinuation
-
1988
- 1988-03-31 EP EP19880200608 patent/EP0285227B1/en not_active Expired
- 1988-03-31 DE DE19883876121 patent/DE3876121T2/en not_active Expired - Fee Related
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2633437A (en) * | 1951-07-31 | 1953-03-31 | Stoelting Bros Co | Method of washing aluminum kitchen utensils |
US3676182A (en) * | 1970-08-31 | 1972-07-11 | Richard Daniel Smith | Treatment of cellulosic materials |
DE2112997A1 (en) * | 1971-02-16 | 1972-09-28 | Heinz Goldbeck | Neutralisation of paper - with alkaline mist using ph measurements for process control |
FR2125963A5 (en) * | 1971-02-16 | 1972-09-29 | Knubben Franz | Regenerating paper prints - treating with alkaline solns to neutralise acidic formations in ageing paper |
US3862916A (en) * | 1973-02-05 | 1975-01-28 | World Patent Dev Corp | Solutions of polyvinyl acetals with phenolic antioxidant in preparation for restoring and/or preserving papers |
US3899439A (en) * | 1973-03-12 | 1975-08-12 | Hercules Inc | Method of preparing aqueous dispersions of hydroxypropyl cellulose |
US3958586A (en) * | 1974-12-04 | 1976-05-25 | Tasope' Limited | Combined washer and dryer unit |
US3939091A (en) * | 1975-02-14 | 1976-02-17 | The United States Of America As Represented By The Librarian Of Congress | Composition for use in deacidification of paper |
Non-Patent Citations (1)
Title |
---|
ABSTRACT BULLETIN OF THE INSTITUTE OF PAPER CHEMISTRY, vol. 54, no. 7, January 1984, page 785, no. 7288, Appleton, Wisconsin, US; N.G. GERASIMOVA et al.: "Study of some aqueous sizes and sizing media used in restoration of paper" & (Leningrad): 60-67 (1977). * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5468706A (en) * | 1993-01-07 | 1995-11-21 | Huels Aktiengesellschaft | Storage-stable solution of a mixture of carbonated magnesium methoxide, carbonated magnesium ethoxide and their carbonated mixed alkoxide in a combination of methanol and ethanol and uses thereof |
US5468705A (en) * | 1993-01-07 | 1995-11-21 | Huels Aktiengesellschaft | Storage-stable solution of carbonated magnesium methoxide in methanol and its use |
EP3339508A1 (en) * | 2016-12-20 | 2018-06-27 | Nitrochemie Aschau GmbH | Process for the treatment of materials containing fibers |
LU93386B1 (en) * | 2016-12-20 | 2018-07-24 | Nitrochemie Gmbh | Process for processing materials containing fibers |
Also Published As
Publication number | Publication date |
---|---|
DE3876121D1 (en) | 1993-01-07 |
NL8700766A (en) | 1988-11-01 |
DE3876121T2 (en) | 1993-04-01 |
EP0285227B1 (en) | 1992-11-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0699033B1 (en) | Process for flavouring shredded tobacco and apparatus for implementing the process | |
CA1300917C (en) | Method and apparatus for film coating seed material | |
WO1999063946A3 (en) | Improved methods and apparatus for storing chemical compounds in a portable inhaler | |
EP0452512A1 (en) | Process involving sterilization step, product having bacteriocidal activity and process for preparing the same, fumigant, fumigation method, and bacteriocidal gas composition, and process and apparatus for preparing the same | |
CA2356908A1 (en) | A method in processing gypsum boards or tiles | |
EP0285227B1 (en) | A process for preserving paper sheets or webs and a device for carrying out that process | |
CA3016961C (en) | Seed injection | |
US5174829A (en) | Removing surface liquid from articles | |
JPH0838813A (en) | Apparatus for treating filter cake | |
JP2719079B2 (en) | Food freshness preservation treatment method | |
US5137760A (en) | Deacidification process | |
KR100617439B1 (en) | Solid water-soluble or water-dispersible compositions | |
JP2002172603A (en) | New function-added lumber, its manufacturing method and its using method | |
EP0377843A2 (en) | Process and system for the production of a porous web provided with adhesive on one side | |
JPH02208486A (en) | Method and device for draining and drying | |
JP2875732B2 (en) | Granular insect repellent | |
CA2537409A1 (en) | Sanitizing food products with recirculating dewatering stream | |
AU634573B2 (en) | Treated bark product | |
AU636342B2 (en) | Generator of isothiocyanic ester vapor, method of sterilizing with isothiocyanic ester vapor, and apparatus therefor | |
JP2001522740A (en) | Composition for coating glass sheet | |
JP2001072026A (en) | Method and device for removing bag | |
WO1991002778A1 (en) | Treated bark product | |
CN221208342U (en) | Waste recovery device for non-woven fabric production | |
CA2050158A1 (en) | Process and apparatus for the discharge of a medium | |
JP2612931B2 (en) | Surface treatment method and device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): BE DE FR GB NL |
|
17P | Request for examination filed |
Effective date: 19890321 |
|
17Q | First examination report despatched |
Effective date: 19910319 |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: B.V.B.A. TECHNISCHE HANDELSONDERNEMING JEZET INTER |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): BE DE FR GB NL |
|
ET | Fr: translation filed | ||
REF | Corresponds to: |
Ref document number: 3876121 Country of ref document: DE Date of ref document: 19930107 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: RN |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: D3 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19970207 Year of fee payment: 10 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19970327 Year of fee payment: 10 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19970410 Year of fee payment: 10 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19970507 Year of fee payment: 10 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY Effective date: 19980331 Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980331 Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980331 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19980331 Year of fee payment: 11 |
|
BERE | Be: lapsed |
Owner name: TECHNISCHE HANDELSONDERNEMING JEZET INTERNATIONAL Effective date: 19980331 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19980331 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19981201 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19991001 |
|
NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee |
Effective date: 19991001 |