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EP0033391B1 - Procédé de fabrication de produits résistant aux inflammations ou incombustibles basés sur des matériaux fibreux - Google Patents

Procédé de fabrication de produits résistant aux inflammations ou incombustibles basés sur des matériaux fibreux Download PDF

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Publication number
EP0033391B1
EP0033391B1 EP80108159A EP80108159A EP0033391B1 EP 0033391 B1 EP0033391 B1 EP 0033391B1 EP 80108159 A EP80108159 A EP 80108159A EP 80108159 A EP80108159 A EP 80108159A EP 0033391 B1 EP0033391 B1 EP 0033391B1
Authority
EP
European Patent Office
Prior art keywords
process according
fibre
added
paste
fiber
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.)
Expired
Application number
EP80108159A
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German (de)
English (en)
Other versions
EP0033391A1 (fr
Inventor
Alfons K. Herr
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
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Individual
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Filing date
Publication date
Priority claimed from DE19803003371 external-priority patent/DE3003371A1/de
Priority claimed from DE19803020033 external-priority patent/DE3020033C2/de
Application filed by Individual filed Critical Individual
Publication of EP0033391A1 publication Critical patent/EP0033391A1/fr
Application granted granted Critical
Publication of EP0033391B1 publication Critical patent/EP0033391B1/fr
Expired legal-status Critical Current

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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
    • 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
    • D21H21/34—Ignifugeants
    • 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
    • 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
    • D21H5/00—Special paper or cardboard not otherwise provided for
    • D21H5/0002—Flame-resistant papers; (complex) compositions rendering paper fire-resistant

Definitions

  • the object of the invention is therefore to introduce such water-soluble fire retardants, in particular boric acid, into the products to be formed from fibrous materials, without the proven and economically feasible wet process in the manufacture of the fiber materials having to be abandoned.
  • Another consideration is that it should be possible; to produce fiber-reinforced gypsum boards based on the known wet process for the production of paper, cardboard, cardboard and fiberboard, which have good strength properties with a low swelling rate and low water absorption capacity.
  • Such gypsum boards are particularly needed for dry interior finishing and plastering of walls, since they not only have good properties that improve the indoor climate and can be nailed by the fiber reinforcement and have sufficient strengths that determine their utility value, but also easy to assemble and, when using the inventive method Process, should also be economically producible. Fire protection would of course also be very important here, since this protection must be required for the interior lining of rooms.
  • the fibrous organic materials which contain boric acid and calcium sulfate as additives, in an economical manner in that the fibrous materials become aqueous Porridge is prepared, that calcium-containing boron minerals and sulfuric acid are intimately mixed into this porridge and that after a ripening period for the conversion of the calcium-containing boron mineral into boric acid and calcium sulfate, the mixture thus formed is fed to nonwoven and fiber dewatering machines, dewatered and then dried.
  • Organic fibers which are inexpensive and partly available as waste products, are used as fibrous materials.
  • the mineral acid is expediently added in a stoichiometric ratio. It can be added in such an amount that the mixture immediately after adding the mineral acid reaches a pH between 1.5 and 3.0, preferably 2.0. A tendency towards neutralization can be achieved when the process is carried out by extending the ripening time after adding the sulfuric acid.
  • the production water is recirculated, as this means that the chemicals dissolved in this production water, in particular the proportion of fire retardants dissolved in the water, are added back to the production process.
  • This production water can also be sprayed back onto the nonwoven fabric on the wire section, whereby water-soluble fire protection agents can also be sprayed on.
  • the fiber suspension which is diluted as necessary in the machine chest, is dewatered on a Fourdrinier machine to form a fiber fleece, which is then fed to the drying tunnel.
  • drying takes place to approx. 5% residual moisture.
  • the inlet temperature in the drying tunnel is kept below 100 ° C so that the fleece is initially evenly heated and the water can still escape from the inside during final drying.
  • a fiber-reinforced gypsum board 225 kg of wood pulp or defibrator material or a mixture of both are introduced into a Dutchman and brought into a fiber suspension with 5% solids content with production water. Then 480 kg of colemanite (approx. 45% boron content) are added and mixed until a homogeneous mixture is obtained. Then 235 kg of sulfuric acid are slowly mixed in, the pH of the acidified mixture should not be below 2.0, but also not above 2.8. This mixture matures in the subsequent storage chest, the pH increasing to 4.5 to 4.8. The fiber mixture is then further processed like a fiber insulation board, but the end product is to be addressed as a reinforced gypsum board.
  • the boric acid content of the gypsum board with circulated production water is about 26% by weight in the end product, so the product is therefore non-flammable in the sense of DIN 4102, class A2.
  • the drainage then takes place on one suitable, known drainage machine.
  • the end result is definitely a reinforced plasterboard, which is not only fire-resistant or non-flammable, but also has remarkable strength properties.
  • Example 2 The same batch of material as in Example 1 is used to produce a fire-protected hardboard. Before the finished fiber-colemanite-sulfuric acid mixture from the Dutch or a mixing chest expires, 0.5 to 2% of an acid-curing synthetic resin is added. After leaving the dewatering machine, the nonwovens are dewatered in a press and pressed to a hardboard, which receives the usual strength through the connection of the fiber under pressure and heat and is also fire-protected.
  • a fiber suspension according to Example 1 For the production of flame-retardant fiber insulation boards that are to be subsequently processed into shaped bodies, a fiber suspension according to Example 1 must first be produced in a Dutch or a mixing chest. After the mixture ripened, the pH rose to about 5.0. Now at least 20 parts by weight of a precipitable thermoplastic in powder or dispersion form are added to the fiber pulp and fixed on the fibers by the usual precipitation process. It is advisable to choose a plastic containing plasticizer. The fiber pulp is then further processed into fiber insulation panels as described in Example 1. The finished fiber insulation board can now be pressed under pressure and heat in a mold made of a matrix and a male mold to form a molded body.
  • the fibrous material should have a solids content of approximately 5% by weight.
  • Fresh water and later the wastewater from the rotary or Fourdrinier machine from the production of such paper is used for the pulp.
  • the fiber / colemanite mixture is then acidified to a pH of 2.0 to 2.5 by slowly adding 117 kg of sulfuric acid.
  • the mixture should then ripen for at least one hour and is then processed as usual. Up to this processing, the pH has increased to approx. 4.5.
  • the end product is a solid, non-flammable paper.
  • Fresh water and, after the start of production, the return water from the suction section of the Fourdrinier machine are used to produce the pulp.
  • the solids content should be 5%.
  • 240 kg of colemanite (approx. 45% boron content) are mixed homogeneously into the pulp.
  • 117 kg of concentrated or the corresponding amount of dilute sulfuric acid are slowly added to the circulating fiber pulp and mixed until the mixture is homogeneous and has a pH of 2.0 to 2. 5 has reached.
  • the fabric can mature in the storage chest; the pH then rose to about 4.5 to 4.8.
  • the mixture is brought to the required level of preparatory work in the machine chest.
  • the fiber pulp is processed as usual. The result is a solid box that is no longer flammable.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Paper (AREA)
  • Producing Shaped Articles From Materials (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • Multicomponent Fibers (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
  • Nonwoven Fabrics (AREA)
  • Porous Artificial Stone Or Porous Ceramic Products (AREA)

Claims (10)

1. Procédé de fabrication de produits difficilement inflammables ou incombustibles, en particulier de produits sous forme de feuille ou de plaque, à base de matières organiques fibreuses, qui contiennent comme additifs de l'acide borique et du sulfate de calcium, caractérisé en ce que l'on convertit les matières fibreuses en une bouillie aqueuse, en ce qu'à cette bouillie on mélange intimement des minéraux borés contenant du calcium et de l'acide sulfurique, et en ce qu'après un temps de maturation pour la conversion du minéral boré contenant du calcium en acide borique et sulfate de calcium, on amène le mélange ainsi formé à des machines de formation de toisons et de déshydratation de fibres, on le déshydrate, et ensuite on le sèche.
2. Procédé selon la revendication 1, caractérisé en ce qu'à la bouillie de fibres mûrie, on ajoute du plâtre.
3. Procédé selon la revendication 1, caractérisé en ce que l'on ajoute de l'acide minéral en quantité telle que le mélange, avant la maturation, atteigne un pH compris entre 1,5 et 3,0, de préférence de 2,0.
4. Procédé selon une ou plusieurs des revendications précédentes, caractérisé en ce qu'à la bouillie de fibres, avant la suite du traitement, on ajoute d'autres minéraux broyés à grain grossier ou fin.
5. Procédé selon une ou plusieurs des revendications précédentes, caractérisé en ce qu'à la bouillie de fibres, avant la suite du traitement, on ajoute des minéraux granulés expansés, en particulier de la vermiculite, de l'argile expansée, du schiste expansé ou de la perlite.
6. Procédé selon une ou plusieurs des revendications, caractérisé en ce que l'on recycle l'eau de production.
7. Procédé selon la revendication 6, caractérisé en ce que l'on pulvérise l'eau de production sur la toison de fibres, sur la partie de tamis.
8. Procédé selon l'une des revendications 6 ou 7, caractérisé en ce qu'à l'eau de production sont ajoutés des agents d'ignifugation hydrosolubles.
9. Procédé selon une ou plusieurs des revendications précédentes, caractérisé en ce que par amenée de deux ou plusieurs corps, on coule, sur une toison préexistante ou en cours de formation, de la bouillie de fibres ayant une teneur relativement élevée en acide borique et sulfate de calcium.
10. Procédé selon une ou plusieurs des revendications précédentes, caractérisé en ce que l'on maintient la bouillie de fibres, pendant son traitement, à une température allant jusqu'à 20° C.
EP80108159A 1980-01-31 1980-12-23 Procédé de fabrication de produits résistant aux inflammations ou incombustibles basés sur des matériaux fibreux Expired EP0033391B1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE19803003371 DE3003371A1 (de) 1980-01-31 1980-01-31 Faserwerkstoff
DE3003371 1980-01-31
DE19803020033 DE3020033C2 (de) 1980-05-24 1980-05-24 Verfahren zum Herstellen schwer entflammbarer oder nicht brennbarer Produkte auf der Basis fasriger Materialien
DE3020033 1980-05-24

Publications (2)

Publication Number Publication Date
EP0033391A1 EP0033391A1 (fr) 1981-08-12
EP0033391B1 true EP0033391B1 (fr) 1983-10-12

Family

ID=25783451

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80108159A Expired EP0033391B1 (fr) 1980-01-31 1980-12-23 Procédé de fabrication de produits résistant aux inflammations ou incombustibles basés sur des matériaux fibreux

Country Status (5)

Country Link
US (1) US4352719A (fr)
EP (1) EP0033391B1 (fr)
CA (1) CA1147911A (fr)
FI (1) FI69161C (fr)
NO (1) NO810285L (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12139438B2 (en) 2019-06-06 2024-11-12 Eco Boron LLC Fire resistant compositions and articles and methods of preparation and use thereof

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3110864C2 (de) * 1981-03-20 1984-10-04 Alfons K. 7513 Stutensee Herr Verfahren zur Herstellung eines asbestfreien Baumaterials
DE3346908A1 (de) * 1983-12-24 1985-07-18 Hornitex Werke Gebr. Künnemeyer GmbH & Co, KG, 4934 Horn-Bad Meinberg Verfahren zur herstellung brandgeschuetzter spanplatten und holzspanformteile
DE4324764A1 (de) * 1993-07-23 1995-01-26 Hans Herberger Bauelement
US6409824B1 (en) 2000-04-25 2002-06-25 United States Gypsum Company Gypsum compositions with enhanced resistance to permanent deformation
US6368529B1 (en) 2000-05-14 2002-04-09 U.S. Borax Inc. Lignocellulosic composite
US7163974B2 (en) * 2000-05-14 2007-01-16 U.S. Borax Inc. Lignocellulosic composites
JP2004504329A (ja) * 2000-07-17 2004-02-12 ユー．エス．ボラックス　インコーポレイテッド 溶解度が混成されているホウ酸塩の防腐防虫剤
US6716310B2 (en) * 2001-12-31 2004-04-06 Kimberly-Clark Worldwide, Inc. Process for manufacturing a cellulosic paper product exhibiting reduced malodor
US20050037221A1 (en) * 2002-07-31 2005-02-17 Fox Roger F. Penetration improvement of copper amine solutions into dried wood by addition of carbon dioxide
CN101338534B (zh) * 2007-07-03 2010-11-17 山西鑫秀工矿废渣利用有限公司 一种工业尾矿或固废物纤维纸浆及其为原料的造纸方法
WO2011116450A1 (fr) * 2010-03-26 2011-09-29 Flamehalt Technologies, Inc. Procédé de formation d'un produit à base de cellulose résistant au feu et appareil associé
US8323785B2 (en) 2011-02-25 2012-12-04 United States Gypsum Company Lightweight, reduced density fire rated gypsum panels
RU2628347C2 (ru) 2012-02-17 2017-08-16 Юнайтед Стэйтс Джипсум Компани Гипсовые изделия с высокоэффективными теплопоглощающими добавками

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3202570A (en) * 1961-06-12 1965-08-24 Wood Conversion Co Method of forming a fiberboard containing a fire-retardant hydrated borate and product thereof
DE1243574B (de) * 1964-01-16 1967-06-29 United States Gypsum Co Verfahren zur Herstellung von Bau- und Isolierplatten
US3453160A (en) * 1963-11-12 1969-07-01 Kaiser Gypsum Co Process for making structural gypsum board for neutron shielding
US3983040A (en) * 1975-08-07 1976-09-28 Draganov Samuel M Fire-retardant composition and process of producing same
DE2831616A1 (de) * 1978-07-19 1980-01-31 Kataflox Patent Nicht brennbarer werkstoff

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE354544C (de) 1920-12-23 1922-06-09 Kurt Joost Dr Ing Verfahren zum Fuellen von Papier im Hollaender
DE947777C (de) 1953-01-30 1956-08-23 Spanitbolaget Torstensson & Co Verfahren zur Behandlung von Holzabfall zwecks Verwendung zusammen mit hydraulischen Bindemitteln zur Herstellung von Baumaterialien
CH354321A (de) 1956-04-13 1961-05-15 Borax Cons Ltd Verfahren zur Herstellung von feuerfestem Papier oder Karton
US2935471A (en) * 1958-09-10 1960-05-03 Du Pont Flame retardant composition
DE1812825U (de) 1960-03-28 1960-06-09 Hartmann & Co W Metallfenster.
US3380842A (en) * 1963-09-20 1968-04-30 Georgia Pacific Corp Decorative composition and a process for its use
GB1025188A (en) * 1964-03-06 1966-04-06 Celotex Ltd Improvements in or relating to fibre building board
US3438847A (en) * 1965-02-26 1969-04-15 Weyerhaeuser Co Process of treating composite boards with borate chemicals produced thereby and product
GB1261134A (en) 1969-11-05 1972-01-19 Ch Traktorny Zd Directional control valves for the power cylinders of operating elements of machines
FR2160810A1 (fr) 1971-11-22 1973-07-06 United States Gypsum Co
US3988199A (en) * 1975-01-27 1976-10-26 Johns-Manville Corporation Perlite insulation board and method of making the same
DE2621739C2 (de) 1976-05-15 1985-10-03 Chemische Fabrik Kalk GmbH, 5000 Köln Verfahren zur Herstellung einer Flammschutzkomponente für Holzspanplatten
US4168175A (en) * 1978-04-26 1979-09-18 Vitrofil Corporation Fire retardant compositions
DE2831633C2 (de) * 1978-07-19 1984-08-09 Kataflox Patentverwaltungs-Gesellschaft mbH, 7500 Karlsruhe Verfahren zur Herstellung eines Brandschutzmittels
US4173666A (en) * 1978-09-11 1979-11-06 Quinto Mario J Flame resistant cellulose fiber insulation and process of preparing it

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3202570A (en) * 1961-06-12 1965-08-24 Wood Conversion Co Method of forming a fiberboard containing a fire-retardant hydrated borate and product thereof
US3453160A (en) * 1963-11-12 1969-07-01 Kaiser Gypsum Co Process for making structural gypsum board for neutron shielding
DE1243574B (de) * 1964-01-16 1967-06-29 United States Gypsum Co Verfahren zur Herstellung von Bau- und Isolierplatten
US3983040A (en) * 1975-08-07 1976-09-28 Draganov Samuel M Fire-retardant composition and process of producing same
DE2831616A1 (de) * 1978-07-19 1980-01-31 Kataflox Patent Nicht brennbarer werkstoff

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12139438B2 (en) 2019-06-06 2024-11-12 Eco Boron LLC Fire resistant compositions and articles and methods of preparation and use thereof

Also Published As

Publication number Publication date
US4352719A (en) 1982-10-05
FI810244L (fi) 1981-08-01
FI69161B (fi) 1985-08-30
NO810285L (no) 1981-08-03
CA1147911A (fr) 1983-06-14
EP0033391A1 (fr) 1981-08-12
FI69161C (fi) 1985-12-10

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