EP0296242A1 - Panneau de laine minerale de faible densite et procede de fabrication de ce panneau - Google Patents

Panneau de laine minerale de faible densite et procede de fabrication de ce panneau

Info

Publication number
EP0296242A1
EP0296242A1 EP88901490A EP88901490A EP0296242A1 EP 0296242 A1 EP0296242 A1 EP 0296242A1 EP 88901490 A EP88901490 A EP 88901490A EP 88901490 A EP88901490 A EP 88901490A EP 0296242 A1 EP0296242 A1 EP 0296242A1
Authority
EP
European Patent Office
Prior art keywords
mineral wool
mass
panel
porous
starch
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.)
Withdrawn
Application number
EP88901490A
Other languages
German (de)
English (en)
Other versions
EP0296242A4 (en
Inventor
David Graham Izard
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.)
USG Interiors LLC
Original Assignee
USG Interiors LLC
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by USG Interiors LLC filed Critical USG Interiors LLC
Publication of EP0296242A1 publication Critical patent/EP0296242A1/fr
Publication of EP0296242A4 publication Critical patent/EP0296242A4/en
Withdrawn legal-status Critical Current

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
    • 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
    • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
    • D21H17/22—Proteins
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F11/00—Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines
    • D21F11/002—Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines by using a foamed suspension
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F11/00—Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines
    • D21F11/02—Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines of the Fourdrinier type
    • 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
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/36—Inorganic fibres or flakes
    • D21H13/38—Inorganic fibres or flakes siliceous
    • D21H13/40—Inorganic fibres or flakes siliceous vitreous, e.g. mineral wool, glass fibres
    • 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
    • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
    • D21H17/24—Polysaccharides
    • D21H17/28—Starch
    • 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
    • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
    • D21H17/24—Polysaccharides
    • D21H17/31—Gums
    • D21H17/32—Guar or other polygalactomannan gum
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21J—FIBREBOARD; MANUFACTURE OF ARTICLES FROM CELLULOSIC FIBROUS SUSPENSIONS OR FROM PAPIER-MACHE
    • D21J1/00—Fibreboard
    • D21J1/16—Special fibreboard
    • D21J1/20—Insulating board

Definitions

  • This invention relates to mineral wool fibrous products.
  • it relates to a method for manufacturing strong, structural panels of mineral fiber that are very lightweight, about 3-10 pounds per cubic foot (50-160 kg/m 3 ) density, and which may be used as acoustical ceiling tiles, thermal insulating panels, sound absorbing panels, pipe and beam insulation and the like products.
  • the water felting of dilute aqueous dispersions of mineral wool and lightweight aggregate is known.
  • a dilute dispersion is flowed onto a moving foraminous support wire screen for dewatering to a mat first by gravity and then by vacuum suction means.
  • the wet mat still containing about 60-80% water, is dried over a number of hours in heated convection drying ovens; and the product is cut and optionally top coated, such as with paint, to produce lightweight structural panels such as acoustical ceiling products.
  • U.S. Patent 4,447,560 suggests a low density sheet by forming a first slurry of fiber that contains synthetic rubber latex solids. A detergent slurry is then formed, and the two slurries admixed to about 15% solids consistency, agitated to a stable foam, and oven dried. The extremely time consuming and energy intensive drying of the stable foam from 15% solids is a severe economic detriment.
  • U.S. Patent 4,062,721 discloses avoiding foam in the forming box so that there is no or minimal foaming when the mat is laid onto the forming wire and during initial gravity drainage, but a foam develops thereafter.
  • An object of the present invention is to provide low density yet strong mineral panels such that panels having densities between about 3-10 pounds per cubic foot (50-160 kg/m 3 ) will have a modulus of rupture of at least about 60 pounds per square inch.
  • the present invention teaches the addition of a delicately foaming binder and a slightly ionic coupling cationic guar gum along with an essentially non-foaming nonionic surfactant dispersing agent into the mixer and thereafter depositing upon the forming wire such an open porous entangled fibrous mass as to allow through-air stripping of water and drying to result in a very stong, low density mineral wool panel.
  • drainage time is reduced rather than increased as suggested by the prior art; and the manufacture of very low density products capable of supporting their own weight without visible sagging, bending or collapsing when supported only at the edges of the panels, as in a suspended ceiling grid, are furthermore attained.
  • a nonionic polyethanoxy surfactant such as a polyethanoxy ether of ethyl alcohol
  • a wheat starch binder having some residual protein fraction, such as about 6% protein residual content
  • a cationic guar gum or guar bean meal derivative such as a trimethylammoniopropyl guar chloride polymer
  • the Figure is a schematic diagram of a mineral board manufacturing process in accordance with the present invention. Description of the Preferred Embodiments
  • a mixing tank 10 containing a motor driven impeller 12 mixes an aqueous slurry 14 containing from about 3% to about 6% solids.
  • the composition of the solids in slurry 14 should be between the following limits: Ingredients Amounts
  • Nonionic Surfactant about 0.5-3%
  • the binder preferably a commercial wheat starch containing about 6% protein fraction (such as GENVIS 600 starch from Ogilvie Mills, Icc.) is dispersed in a portion of the process water in mixing tank 16 with high shear cyclone mixer 18 and then heated to a temperature between about 135° and 190°F (57°-88°C) to cook the starch. There is no substantial increased viscosity apparent with this starch during the cooking cycle and, after cooling, the starch binder is fed to mixing tank 10. It is important that no substantial viscosity increase of the slurry is provided by the binder as such is detrimental to maintaining a rapid rate of dewatering and drying the wet mat.
  • GENVIS 600 starch from Ogilvie Mills, Icc.
  • a nonionic polyethanoxy surfactant was added to the slurry in mixing tank 10. It is preferred to use an about 2% solution form, such as IGEPAL polyethoxylate from GAF Chemicals Corporation.
  • IGEPAL polyethoxylate from GAF Chemicals Corporation.
  • the mineral fiber for use in the present invention may be any of the conventional fibers prepared by attenuating a molten stream of basalt, slag, granite or other vitreous mineral constituent drawn linearly through orifices, referred to commonly as textile fibers, or tangentially off the face of a spinning cup or rotor, referred to as wool fibers. Included also are ceramic fibers and the like and aromatic polyamid fibers and the like. Porous bonded mats or batts of fibers may be used as well as individual fibers to form structures of the invention.
  • the lightweight aggregate preferably is an inorganic lightweight aggregate of exfoliated or expanded volcanic glass origin.
  • Such aggregate includes the well known expanded perlite, exfoliated vermiculite, exfoliated clays and the like products which are available in a variety of mesh sizes.
  • expanded perlite is preferred for reasons of avai labi lity and economy .
  • the homogeneously mixed, and ionically coupled and slightly foamed slurry is deposited on the wire 40 as a very open, porous entangled mass of mineral wool and lightweight aggregate with a small amount of uniformly sized transient bubbles of air.
  • the air occupies about 10-30% by volume of the wet entangled mass at this time, the remainder of the interstices between the lightweight aggregate and preferred nonionic polyethanoxy surfactant is a low foaming water soluble surfactant of dinonylphenoxy poly(ethyleneoxy) ethanol having a molecular weight of about 995.
  • Similar polyethanoxy ethers of ethyl alcohol are commercially available and may be used.
  • the cationic bean meal derivative such as a commercially available powdered polymer of trimethylammoniopropyl guar (GENDRIV from Henkel Corporation) like guar 2-hydroxy-3 (trimethyl-amino)-propyl ether chloride is added to the main mixing tank 10, where it readily disperses in the mix water to form a solution of appropriate concentration exhibiting flocculating and solids retention capability with the mineral wool and lightweight aggregate, such as expanded perlite, ingredients that are also added directly to mixing tank 10.
  • the guar derivative tends to flocculate the mineral wool and the effect is enhanced with the addition of small amounts of clay.
  • the cationic guar derivative was added to mixing tank 10 last after thorough homogeneous mixing of all the other ingredients, with mixing continued for a few seconds before transferring the slurry from mix tank 10 by pump 20 to flow box 30.
  • the function of the flow box 30 is to spread a uniform layer of slurry 32 across the width of a mixing wire belt 40, commonly called the wire, to form an open, porous wet mat 62.
  • the open, porous mat 62 is preferrably of a thickness to yield a finished product having a thickness between about 1/4 and 2 inches.
  • the nonionic polyethanoxy surfactant be a low foaming surfactant and that it be added early in the mixing, as in mixing tank 10, along with the early addition of the cationic quar gum derivative flocculant in order to establish thorough dispersion of the mineral wool and lightweight aggregate with ionic coupling of the wheat starch binder protein via the cationic quar onto the mineral surfaces and further along with a low foaming prior to the slurry passing through the flow box 30 and being deposited upon the forming wire 40.
  • the mineral fiber for use in the present invention may be any of the conventional fibers prepared by attenuating a molten stream of basalt, slag, granite or other vitreous mineral constituent drawn linearly through orifices, referred to commonly as textile fibers, or tangentially off the face of a spinning cup or rotor, referred to as wool fibers. Included also are ceramic fibers and the like and aromatic polyamid fibers and the like. Porous bonded mats or batts of fibers may be used as well as individual fibers to form structures of the invention.
  • the lightweight aggregate preferably is an inorganic lightweight aggregate of exfoliated or expanded volcanic glass origin.
  • Such aggregate includes the well known expanded perlite, exfoliated vermiculite, exfoliated clays and the like products which are available in a variety of mesh sizes.
  • expanded perlite is preferred for reasons of availability and economy.
  • the homogeneously mixed, and ionically coupled and slightly foamed slurry is deposited on the wire 40 as a very open, porous entangled mass of mineral wool and lightweight aggregate with a small amount of uniformly sized transient bubbles of air.
  • the air occupies about 10-30% by volume of the wet entangled mass at this time, the remainder of the interstices between the lightweight aggregate and mineral fiber comprising water, and the aqueous slurry at this point containing still about 3-6 weight % solids.
  • the open lightly foamed wet mass is deposited from forming box 30 onto a bottom scrim cover sheet 43 above the wire 40 as the slurry and scrim 43 float through a first flooded section 42 on the moving wire 40.
  • High vacuum drainage section 44 Discharge of water from the open wet slightly foamed mass occurs in high vacuum drainage section 44, as a top cover sheet 47 is optionally laid over the open wet porous foam mass via roller 36.
  • high vacuum section 44 a couple of very brief bursts of a pressure differential equivalent to about 3-20 (.8-.5m) inches of mercury busts the bubble walls of the slight foam that had been formed and strips water from the wet mass. It was observed in this section of the process that in a matter of 1-3 seconds the foam has collapsed and the draining liquid coats the contact points on the highly voided, open, entangled mass of the fiber and aggregate scrim cover sheet (s).
  • a fully dried panel may be obtained by augmenting through-air drying with supplemental conventional convection drying (not shown in the drawing) in a matter of a couple additional minutes drying time.
  • the mat was formed upon and became an integral part of the final panel product with 1 or 2 fiber glass nonwoven scrim cover sheets.
  • Such sheets may be of paper, woven glass fiber, non-woven glass fiber and the like open, porous sheet materials.
  • a particularly preferred cover sheet is a non-woven fiber scrim, such as battery type scrim, having a weight of about 0.4-2.5 pounds per hundred square feet of scrim.
  • the top scrim 47 may be left off and, after the water stripping and drying section 49, a viscous, screedable pulp such as that set forth in U.S.
  • Patents 1,769,519; 1,996,033; or 3,246,063 may be applied as an overlay and the wet pulp surface textured by suitable means to provide a pleasing appearance, and the composite panel-overlay dried in a conventional convection drying oven (not shown in the drawing).
  • a conventional convection drying oven not shown in the drawing.
  • both top and bottom scrims may be in place before application of such a pulp overlay.
  • conventional finishing operations such as the application of various prime, texture, or protective coatings of a paint or texture and the like may be applied to the panels produced in accordance with the present invention.
  • a cationic guar bean meal derivative (guar 2-hydroxy-3 (trimethylammonio)-propyl ether chloride, GENDRIVE 158 from Henkel Corporation) was dispersed in water by mixer 16 to form a solution.
  • Mineral wool, expanded perlite aggregate, dinonylphenoxypoly (ethyleneoxy) ethanol (IGEPAL-DM710 from GAF Chemicals Corporation) nonionic polyethanoxy surfactant, and CTS ball clay were added to main mixer 10 and mixed for 4 minutes.
  • the cationic guar derivative solution was added to main mixer 10 for flocculation and mixed for 5 seconds before passing the dilute dispersion to forming box 30.
  • main mixer 10 On a solids basis, the final proportioning in main mixer 10 was 44.45% mineral wool, 29.15% expanded perlite, 22.95% wheat starch having 6% residual protein fraction (GENVIS 600 from Ogilvie Mills Inc. cooked at 190°F (88°C) in mixer 16), 1.68% CTS-2 clay and 1.68% nonionic polyethanoxy surfactant in about 3% solids dispersion.
  • the ordinarily first gravity drainage box section of the wire 40 was flooded with water to the level of the scrim and the dilute furnish passed from the main mixer to the flow box 30 and deposited onto the scrim (battery grade 2.4 pounds per hundred square feet (.12 kg/m 2 ) of nonwoven fiber glass scrim).
  • the heated dry air may be provided at a temperature of about
  • the time for passage from the flow box 30 through the through-air drying section 48 varied considerably, depending upon core thickness of about 1/8th inch (.003m) through 2 inches (.05m) thickness, generally from about 2 to 10 minutes.
  • core thickness was 0.445-0-0.490 inches at 6.3-7.0 pounds per cubic foot density range.
  • the addition of a paint coat added another 2.5 pounds per cubic foot to the core density.
  • the average modulus of rupture was 120 pounds per square inch and acoustical properties testing exhibited an average noise reduction coefficient of 0.75.
  • EXAMPLE 2 In a series of short static board forming runs, various of the components were evaluated for effect in panel formation by "halving" and then doubling the presently preferred amount of the particular component as used in Example 1. As part of these evaluations, the weight of the produced panel after the through-air-drying procedure (T-A-D weight) was measured; and then the samples were placed in a convection oven and dried overnight to a constant weight (Oven weight) for comparison and the difference in weight from through-air drying to bone dry weight was determined. Representative results are set forth in the Table.
  • Doubling the amount of the low foaming dispersant-surfactant nonionic polyethanoxylate did not significantly change the nature of the rather delicate, non-resilient bubbles; did not significantly inhibit bursting of the bubbles and stripping of water by through-air passage; and did not result in significant separation of fiber and aggregate during water stripping.
  • a number of previous attempts encountered considerable layering of the ingredients due to perlite segregating and floating and starch and wool fiber segregating and sinking, and the layering destroying the rapid through-air drainage.
  • the present invention provides a method for manufacturing structural mineral panel products of widely varying densities, properties and uses.
  • Various panel thicknesses from about l/8th inch through 2 inches (.003-.05m) or more may be formed.
  • Additional ingredients and other adjuvants customary in the art for particular added purposes may be present, even in major amounts, for their known effects. For example, dyes, pigments, antioxidants, water repellants, fire retardants, biocides and the like may be added.
  • Additonal conventional steps for forming particular various manufactured articles such as cutting, trimming, shaping, adding slots, tabs and the like for ceiling grid suspension or other mountings; painting, texturing, surface overlaying and the like decorating and finishing features including protective top coatings may be performed without departing from the spirit and scope of the present invention.
  • Various apparatus may be utilized as mixing vessels including turbine and impeller mixers of various configuration and design, and various flow boxes including flotation foaming cells and conventional forming head boxes as used in conventional batch and continuous foraminous support wire forming operations may be used.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Paper (AREA)
  • Laminated Bodies (AREA)

Abstract

Procédé de fabrication de panneaux de laine minérale de très faible densité pour la construction passant sur une grille poreuse en mouvement. Une couche fibreuse de laine minérale additionnée d'eau formant un agrégat de faible densité est mélangée avec de l'amidon de blé cuit, de la gomme de guar et un agent de surface tensio-actif non ionique pour former une petite quantité de mousse délicate non résiliente et associer ioniquement les surfaces minérales à l'amidon et à la gomme, le tout étant déposé sur la grille (40) pour former une masse poreuse ouverte aux éléments entremêlés, qui est rapidement débarrassée de son eau et séchée dans une cuve de circulation (49).
EP19880901490 1987-01-12 1988-01-12 Low density mineral wool panel and method Withdrawn EP0296242A4 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US251287A 1987-01-12 1987-01-12
US2512 1987-01-12

Publications (2)

Publication Number Publication Date
EP0296242A1 true EP0296242A1 (fr) 1988-12-28
EP0296242A4 EP0296242A4 (en) 1991-07-10

Family

ID=21701126

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19880901490 Withdrawn EP0296242A4 (en) 1987-01-12 1988-01-12 Low density mineral wool panel and method

Country Status (8)

Country Link
EP (1) EP0296242A4 (fr)
JP (1) JPH01501859A (fr)
KR (1) KR890700715A (fr)
AU (1) AU611668B2 (fr)
BR (1) BR8804822A (fr)
NZ (1) NZ223122A (fr)
WO (1) WO1988005096A1 (fr)
ZA (1) ZA8864B (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11255051B2 (en) 2017-11-29 2022-02-22 Kimberly-Clark Worldwide, Inc. Fibrous sheet with improved properties
US11313061B2 (en) 2018-07-25 2022-04-26 Kimberly-Clark Worldwide, Inc. Process for making three-dimensional foam-laid nonwovens
US11591755B2 (en) 2015-11-03 2023-02-28 Kimberly-Clark Worldwide, Inc. Paper tissue with high bulk and low lint

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2811662B1 (fr) * 2000-07-13 2003-07-18 Saint Gobain Isover Produit d'isolation thermique/phonique a base de laine minerale
EP2136010A1 (fr) * 2008-06-17 2009-12-23 Rockwool International A/S Système de construction pour structure de construction
SE2150053A1 (en) * 2021-01-19 2022-07-20 Fibu Ab Method for producing 3d fiber structures

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1841785A (en) * 1930-06-19 1932-01-19 Cellufoam Corp Method of making layers of distended fibrous materials
US3090699A (en) * 1960-05-12 1963-05-21 Armstrong Cork Co Sag-resistant fiberboard and method of making same
US4062721A (en) * 1976-10-26 1977-12-13 Conwed Corporation Use of surfactant to increase water removal from fibrous web

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
No further relevant documents have been disclosed. *
See also references of WO8805096A1 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11591755B2 (en) 2015-11-03 2023-02-28 Kimberly-Clark Worldwide, Inc. Paper tissue with high bulk and low lint
US11255051B2 (en) 2017-11-29 2022-02-22 Kimberly-Clark Worldwide, Inc. Fibrous sheet with improved properties
US11313061B2 (en) 2018-07-25 2022-04-26 Kimberly-Clark Worldwide, Inc. Process for making three-dimensional foam-laid nonwovens
US11788221B2 (en) 2018-07-25 2023-10-17 Kimberly-Clark Worldwide, Inc. Process for making three-dimensional foam-laid nonwovens

Also Published As

Publication number Publication date
KR890700715A (ko) 1989-04-26
ZA8864B (en) 1988-12-28
EP0296242A4 (en) 1991-07-10
AU1243588A (en) 1988-07-27
AU611668B2 (en) 1991-06-20
WO1988005096A1 (fr) 1988-07-14
JPH01501859A (ja) 1989-06-29
NZ223122A (en) 1991-02-26
BR8804822A (pt) 1989-10-03

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