EP4179142A1 - Verfahren zur herstellung von nasslaufreibpapier - Google Patents
Verfahren zur herstellung von nasslaufreibpapierInfo
- Publication number
- EP4179142A1 EP4179142A1 EP21734272.4A EP21734272A EP4179142A1 EP 4179142 A1 EP4179142 A1 EP 4179142A1 EP 21734272 A EP21734272 A EP 21734272A EP 4179142 A1 EP4179142 A1 EP 4179142A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- binder
- pulp
- fiber
- wet
- filler
- 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
- D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
- D21H27/18—Paper- or board-based structures for surface covering
- D21H27/22—Structures being applied on the surface by special manufacturing processes, e.g. in presses
- D21H27/26—Structures being applied on the surface by special manufacturing processes, e.g. in presses characterised by the overlay sheet or the top layers of the structures
- D21H27/28—Structures being applied on the surface by special manufacturing processes, e.g. in presses characterised by the overlay sheet or the top layers of the structures treated to obtain specific resistance properties, e.g. against wear or weather
-
- 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
- D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
- D21H17/20—Macromolecular organic compounds
- D21H17/33—Synthetic macromolecular compounds
- D21H17/46—Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- D21H17/47—Condensation polymers of aldehydes or ketones
- D21H17/48—Condensation polymers of aldehydes or ketones with phenols
-
- 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
- D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
- D21H17/63—Inorganic compounds
- D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
-
- 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
- D21H23/04—Addition to the pulp; After-treatment of added substances in the pulp
- D21H23/06—Controlling the addition
- D21H23/08—Controlling the addition by measuring pulp properties, e.g. zeta potential, pH
Definitions
- the invention relates to a method for producing a wet-running friction paper containing at least one portion of fibers made from at least one type of fiber, one portion of at least one filler and one portion of a binder based on phenolic resin.
- GB-A-2205592 describes a friction lining material, described as wet-running friction paper, made of a porous fibrous base material, an inert filler and phenolic resin, the fibrous base material being processed in an aqueous slurry, the phenolic resin in the form of an emulsion and the filler being processed into a stock solution.
- the stock solution is applied to a fourdrinier wire in the form of a papermaking process, then rolled and dried. During the drying process, the phenolic resin is hardened under the influence of temperature.
- the object of the invention is the further development of a method for producing a wet friction paper.
- the object of the invention is to simplify the production of a wet friction paper and to improve its properties.
- the proposed method is used to produce a wet-running friction paper or a layered friction material for friction, clutch and/or brake devices, in particular in a motor vehicle.
- the wet friction paper contains a fiber content of at least one fiber type, for example aramid fibers, carbon fibers, cotton fibers such as lint fibers and/or the like Chen, a proportion of at least one filler, for example kieselguhr such as Celite, graphite, coke and / or the like and a proportion of a binder based on phenolic resin, for example phenol resol and / or the like. Additional components such as silicone resin, silanes, flocculants, retention aids, friction particles and/or the like can be provided.
- the wet friction paper is produced in a paper manufacturing process.
- a slurry such as a pulp or suspension is formed from the fiber portion and the at least one filler.
- the fibers are available in short cut form, for example with a length of a few millimeters.
- the highly water-containing pulp also contains the binder portion, in which a phenolic resin portion is optionally present in addition to other resin portions as a phenolate, in which the phenolic resin is dissolved in a highly alkaline solution, for example in a sodium hydroxide or potassium hydroxide solution.
- the pulp is processed into wet-run friction paper in a papermaking process known per se.
- the pulp is placed on a fourdrinier wire and rolled and gauged in a wet press unit.
- the pulp is then optionally dried with further rolling.
- corresponding rollers can be brought to higher temperatures than the rollers in the wet phase in order to evaporate the remaining solvent, for example water.
- the phenolic resin component present in the pulp as a phenolate of the phenolic resin is precipitated.
- the pH of the alkaline pulp is lowered by adding acid, for example the pulp is neutralized, as a result of which the phenolate is converted into an insoluble phenolic resin and precipitated.
- a dilute acid such as 5% sulfuric acid can be used as a solvent.
- the precipitation process preferably takes place in the wet phase at room temperature or the ambient temperature of the papermaking process.
- a uniform distribution of precipitated phenolic resin particles can be achieved over the entire area of the pulp lying on the fourdrinier wire.
- a lateral distribution of the phenolic resin particles and across its thickness between the two surfaces can be achieved, so that the friction quality of a friction partner made from the wet-running friction paper essentially remains the same over its service life Has friction properties.
- a particle size of precipitated binder particles such as phenolic resin particles can be adjusted by means of a predetermined addition rate of the precipitant.
- Particularly small particle diameters of the phenolic resin, in particular phenolic resol in the range of 200 to 1600 nanometers, can be achieved by adding the precipitant at an appropriate rate, for example 0.5 kg/s accumulate evenly on the fibers.
- a suitable zeta potential of, for example, 80 mV ⁇ 8 mV can be set, so that a high conversion of the floc can essentially be achieved with 100% addition of the phenolic resin.
- Improved reinforcement properties for example in the gluing process of the wet running paper on a corresponding carrier such as carrier plate or the like, are achieved by appropriate adjustment of the rheological properties of the pulp. Setting the viscosity to less than 3000 Pa*s, based on a service life of 800 s, has proven to be advantageous here. It goes without saying that the viscosity can change with other service lives and it may be necessary to trace the viscosity back to the specified service life in order to determine its viscosity.
- the degree of hardness of the binder such as phenolic resin and thus its abrasion resistance, elasticity, temperature resistance and/or the like can be adjusted in a dry phase of the papermaking process.
- a uniform temperature can be set on the rollers or the temperature curve can be set to rise or fall gradually from roller to roller during the drying phase.
- the positive properties of wet running paper, in particular its reinforcing effect when it is glued to a carrier material, depends on the setting of the activation potential of the curing process of the binder.
- the phenolic resin and its reactants are advantageously adjusted in such a way that the activation energy of the curing process is greater than 60 KJ/mol with a frequency factor In20 and a reaction order of ⁇ 1.5.
- An advantageous composition for producing the wet friction paper can, for example
- a fiber content of 40 to 60% by weight in particular a mixture of aramid fibers, lint fibers and carbon fibers, - a binder content of 30 to 40% by weight, in particular phenolic resin, present as a phenolate in an alkaline solution,
- a particularly advantageous composition contains in percent by weight, for example
- phenolic resin such as phenolic resol, present as a phenolate in a strongly alkaline solution with subsequent precipitation
- inventive idea also includes the described wet friction paper, produced in particular according to the proposed method.
- the wet friction paper has an even distribution of resin particles between its two opposing surfaces.
- the particle size of binder particles formed from the binder portion is preferably between 200 and 1600 nm.
- the wet friction paper is in sheet form or roll form after the completion of the papermaking process.
- the production of friction linings from this wet-running friction paper takes place depending on later use as a radially or axially effective friction lining by stamping, cutting out or the like in the form of a ring or ring segment with radial or axial friction surfaces.
- profiling of the surfaces of the friction lining or of the friction surfaces can be applied to the friction surfaces provided Nassertonreibpapiers be seen, for example, by a different intensity of pressure before.
- application-specific, necessary punctures can be provided.
- the particle size of the precipitated resin particles is adjusted by means of a combination of the properties of the binder, in particular a phenol resol, and the precipitation conditions of the phenolate by means of an adjusted pH value of the acid used, such as sulfuric acid, and the precipitation rate, i.e. the addition rate of the Acid.
- the rheological properties are adjusted by adding appropriate water or solvents and, if necessary, adding superplasticizers in order to ensure the reinforcing effect through sufficient flow of the resin.
- the setting of the zeta potential is set by the quality of the binder, example, its polarity and the type and number of functional groups and the properties of the pulp.
- the setting of the described zeta potential serves as a prerequisite for the precipitated particles to be securely bound to the fiber portion.
- the reaction behavior with the specified activation energy serves to ensure that the wet running paper in combination with the adjustment of the drying of the pulp necessary curing is achieved, as well as good final curing during the adhesive process during bonding to a carrier material.
- the activation energy By setting the activation energy accordingly, it is achieved on the one hand that sticking of the wet paper to the drying cylinder during the dryer section of the paper machine is avoided and on the other hand sticking times of the wet paper to the carrier material are preferably well under one minute.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Paper (AREA)
- Braking Arrangements (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
Abstract
Description
Claims
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102020118410 | 2020-07-13 | ||
| DE102020123040.0A DE102020123040A1 (de) | 2020-07-13 | 2020-09-03 | Verfahren zur Herstellung von Nasslaufreibpapier |
| PCT/DE2021/100496 WO2022012708A1 (de) | 2020-07-13 | 2021-06-09 | Verfahren zur herstellung von nasslaufreibpapier |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP4179142A1 true EP4179142A1 (de) | 2023-05-17 |
| EP4179142B1 EP4179142B1 (de) | 2025-12-24 |
Family
ID=79020039
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP21734272.4A Active EP4179142B1 (de) | 2020-07-13 | 2021-06-09 | Verfahren zur herstellung von nasslaufreibpapier |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US20240035235A1 (de) |
| EP (1) | EP4179142B1 (de) |
| JP (1) | JP7516650B2 (de) |
| CN (1) | CN115702276A (de) |
| DE (1) | DE102020123040A1 (de) |
| WO (1) | WO2022012708A1 (de) |
Family Cites Families (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2899353A (en) * | 1959-08-11 | Flexible paper web and process of | ||
| DE2817699A1 (de) * | 1978-04-22 | 1979-10-31 | Hoechst Ag | Verfahren zur herstellung von stark profilierten formteilen |
| GB2126594B (en) * | 1982-08-11 | 1985-10-09 | Borg Warner | Dry friction composition |
| EP0129022A3 (de) * | 1983-04-25 | 1986-01-02 | Borg-Warner Corporation | Verfahren zur Herstellung eines trockenen Reibungsmaterials |
| GB2163784B (en) | 1984-08-30 | 1987-06-10 | Ferodo Ltd | Wet laid friction facing material |
| GB2205592B (en) | 1987-06-11 | 1991-03-13 | Ferodo Ltd | Asbestos-free friction facing material |
| JP3023847B2 (ja) * | 1990-11-26 | 2000-03-21 | イビデン株式会社 | 湿式摩擦材の製造方法及び摩擦材 |
| CZ285982B6 (cs) * | 1991-05-09 | 1999-12-15 | Isover Saint-Gobain | Způsob přípravy fenolového pojiva |
| US5714544A (en) * | 1993-08-05 | 1998-02-03 | Mitsubishi Gas Chemical Company, Inc. | Process for the production of phenolic resin and epoxy resin composition |
| JP3459094B2 (ja) * | 1993-11-16 | 2003-10-20 | 旭有機材工業株式会社 | フェノール樹脂複合体の製造方法 |
| JPH1036522A (ja) * | 1996-07-25 | 1998-02-10 | Nippon Aramido Kk | 摩擦材の製造方法 |
| FR2779989B1 (fr) | 1998-06-17 | 2000-08-04 | Valeo | Procede de fabrication d'un materiau de friction et plus particulierement d'une couronne de friction pour disque de friction d'embrayage et couronne d'embrayage |
| EP1743975B1 (de) * | 2004-02-19 | 2019-04-10 | Toray Industries, Inc. | Nanofasern enthaltende konfektionierte lösung, emulsion und gelmasse und verfahren zu deren herstellung sowie nanofasern enthaltendes synthesepapier sowie herstellungsverfahren dafür |
| WO2006116474A2 (en) | 2005-04-26 | 2006-11-02 | Borgwarner Inc. | Friction material |
| KR20080083170A (ko) * | 2005-12-21 | 2008-09-16 | 이 아이 듀폰 디 네모아 앤드 캄파니 | Pipd 섬유를 함유하는 마찰 종이 |
| US8389107B2 (en) * | 2008-03-24 | 2013-03-05 | Biovation, Llc | Cellulosic biolaminate composite assembly and related methods |
| JP5748600B2 (ja) * | 2011-08-01 | 2015-07-15 | トヨタ自動車株式会社 | 湿式摩擦材及びその製造方法 |
| RU2570515C2 (ru) * | 2011-08-18 | 2015-12-10 | Федерал-Могал Корпорейшн | Фрикционный материал для изготовления тормозного устройства, тормозная колодка и способ ее изготовления |
| JP2014208769A (ja) | 2013-03-27 | 2014-11-06 | 住友ベークライト株式会社 | 湿式摩擦材用樹脂組成物、湿式摩擦材用フェノール樹脂及び湿式摩擦材 |
| EP3504376B1 (de) | 2016-08-24 | 2020-10-07 | Teijin Aramid B.V. | Reibungsmaterial mit aramid |
| DE102019126429A1 (de) | 2019-07-26 | 2021-01-28 | Schaeffler Technologies AG & Co. KG | Verfahren zur Herstellung von Nasslaufreibpapier und Nasslaufreibpapier |
| CN110701226A (zh) * | 2019-09-27 | 2020-01-17 | 中国第一汽车股份有限公司 | 一种纤维增强的dct湿式离合器摩擦纸及其制备方法 |
-
2020
- 2020-09-03 DE DE102020123040.0A patent/DE102020123040A1/de active Pending
-
2021
- 2021-06-09 CN CN202180043895.5A patent/CN115702276A/zh active Pending
- 2021-06-09 US US18/005,185 patent/US20240035235A1/en active Pending
- 2021-06-09 WO PCT/DE2021/100496 patent/WO2022012708A1/de not_active Ceased
- 2021-06-09 EP EP21734272.4A patent/EP4179142B1/de active Active
- 2021-06-09 JP JP2023501808A patent/JP7516650B2/ja active Active
Also Published As
| Publication number | Publication date |
|---|---|
| JP2023534670A (ja) | 2023-08-10 |
| JP7516650B2 (ja) | 2024-07-16 |
| EP4179142B1 (de) | 2025-12-24 |
| WO2022012708A1 (de) | 2022-01-20 |
| US20240035235A1 (en) | 2024-02-01 |
| CN115702276A (zh) | 2023-02-14 |
| DE102020123040A1 (de) | 2022-01-13 |
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