Classifications

• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06B—TREATING TEXTILE MATERIALS USING LIQUIDS, GASES OR VAPOURS
  • D06B19/00—Treatment of textile materials by liquids, gases or vapours, not provided for in groups D06B1/00 - D06B17/00
  • D06B19/0088—Treatment of textile materials by liquids, gases or vapours, not provided for in groups D06B1/00 - D06B17/00 using a short bath ratio liquor
  • D06B19/0094—Treatment of textile materials by liquids, gases or vapours, not provided for in groups D06B1/00 - D06B17/00 using a short bath ratio liquor as a foam

Definitions

• This invention pertains to treating a porous substrate by impregnating the substrate with a foam.
• this invention relates to 5 transporti ng a porous substrate past an applicator which injects foam into the porous substrate, thereby impregnating or coating the porous substrate.
• a common practice in the manufacture of porous 0 substrates is to apply a coating of various materials thereto.
• carpet material for example, it is necessary to dye the carpet to the desired color during the manufacturing process.
• many types of fibrous and non-fibrous webs or blankets require a 5 binder to bond the fibers or other particles together to form a cohesive product.
• An example of this is an insulation pack produced by bonding together mineral fibers, such as glass fibers.
• a typical binder for a glass fiber insulation pack is a phenol -formal dehyde-urea binder. Q The binder is applied to the fibers, and, when cured, the binder enables the insulation pack to be compressed with nearly full recovery upon release of the compression.
• binder, dye or any other coating material has been by one of several methods.
• the common method in the manufacture of mineral fiber packs is to spray a binder material or coating
• OMPI 1 material onto the fibers prior to collecting the fibers in the form of an insulation pack has certain deficiencies in that the binder has to be applied in a hot fiber-forming zone, thereby creating air pollution 5 problems. Also, binder application onto air-borne fibers is inherently non-uniform.
• Another process for applying coatings to porous substrates is that of transporting the substrate through a liquid bath, such as is used to dye fabrics, including carpets. This process is deficient in 0 that a large percentage of water or other carrier medium remains in the porous substrate after the coating process, and must be removed by costly methods, such as by drying ovens. Also, liquid bath applicators provide no control of penetration of the liquid into the substrate.
• Another method for coating porous substrates is that of creating a foam containing the coating material, such as the binder or the dye, and impregnating the porous material with the foam.
• the use of the foam material facilitates a uniform coating on all the material of the 0 substrate, and applies the coating with a minimum amount of carrier medium, such as water.
• the foams are applied as a layer to the substrate, and caused to impregnate the substrate by the use of a doctor blade.
• a process for forcing a layer of foam into a porous substrate 5 is already known in the art. This process provides for a suction apparatus to force the binder foam into the insulation pack.
• the foraminous nature of the surface enables air to escape from the pack during the compression process.
• the pressurized foam is able to partially or fully impregnate the insulation pack, and the urging of the substrate into sealed relation with the surface plate at the nip region insures that the foam material will pass through the surface and into the interior of the insulation pack rather than travel along the interface between the insulation pack and the discharge head.
• the method and apparatus of this invention can apply foams at very high pressures, and are not limited to sub-atmospheric pressures.
• the invention can be used to apply foam to substrates having very low tensile strengths, since the substrate is driven by the foraminous surface. Further, a greater control of the penetration of the foam can be effected with the present invention.
• apparatus for impregnating a porous substrate with a foam comprising a foam discharge head having a surface plate adapted with one or more discharge openings for the discharge of foam therefrom, a foraminous surface positioned opposite the discharge openings to define a nip region having a thickness less than the thickness of the porous substrate, with the foraminous conveyor being adapted to transport the porous substrate through the nip region and to urge, with the foam discharge head, the porous substrate into sealed relation with the surface plate at the nip region, and means for supplying foam to the foam discharge head with pressure sufficient to impregnate the porous substrate.
• the means for supplying foam supplies foam to the foam discharge head at a pressure within the range of from about 21 to about 126 kilopascals.
• a radio-frequency dryer removes water from the porous substrate subsequent to its being impregnated with foam.
• a second foraminous surface and a second foam discharge head are adapted to discharge foam through another side of the porous substrate.
• the discharge openings comprise a plurality of holes positioned in the surface plate.
• the holes can be arranged in rows, with the holes in one row being offset or staggered with respect to its adjacent row.
• the nip region has a minimum thickness within the range of from about 5 to about 20 percent of the thickness of the fibrous web when uncompressed.
• the foraminous surface is convex within the nip region in the direction of the foam discharge head.
• means for urging the foam discharge head toward the foraminous surface to urge the porous substrate into sealed relation with the surface plate so that foam is prevented from accumulating at the interface of the foam discharge head and the porous substrate as the porous substrate is transported through the nip region.
• the means for urging can also be adapted to urge the foraminous surface toward the foam discharge head.
• the means for urging comprises a pneumatic means.
• a method for impregnating a porous substrate with a foam comprising transporting the porous substrate through a nip region defined by a foraminous surface and a foam discharge head, the foam discharge head including a surface plate having one or more discharge openings, where the transport of the porous substrate through the nip region causes the porous substrate to be urged into sealed relation with the surface plate as the substrate passes the discharge openings, and supplying foam to the discharge head with pressure sufficient to impregnate the porous substrate.
• water is removed from the porous substrate with a radio- frequency dryer subsequent to impregnating the substrate with foam.
• one side of the porous substrate is impregnated with the first foraminous conveyor and first foam discharge head, and the other side of the porous substrate is impregnated with a second foraminous conveyor and a second foam discharge head .
• the discharge openings comprise at least 2 rows of holes, with the holes in one row being offset with respect to its adjacent row.
• FIG. 1 is a schematic view in ele.vation of apparatus for impregnating a porous substrate with a foam according to the principles of this invention.
• FIG. 2 is a schematic view in perspective of the apparatus shown in FIG. 1.
• FIG. 3 is a view in elevation of a different embodiment of the foraminous surface.
• FIG. 4 is a view in elevation of yet another 5 embodiment of the foraminous surface.
• FIG. 5 is a view in elevation of a different embodiment of means for urging the foam discharge head toward the foraminous drum.
• FIG. 6 is a schematic view of an embodiment of 0 the surface of the drum.
• the unimpregnated porous substrate such as glass fiber insulation pack 10 is driven past bottom foam discharge head 12 by a foraminous surface, such as first rotating foraminous drum 14.
• the foraminous drum can be made of any suitable - material , such as stainless steel , and is adapted with a plurality of perforations, such as perforations 15.
• the perforations give the drum a porosity of about 0.5.
• the positioning of the first foraminous drum opposite the foam discharge head defines nip region 17 through which the insulation material must pass.
• the foraminous surface such as the foraminous drum, is convex within the nip region in the direction of the foam discharge head, i.e., in a downward direction for the apparatus shown in FIG. 2.
• the insulation material can be considerably compressed, as shown.
• the insulation material is compressed in the nip region to a thickness within the range of from about 5 to about 20 percent of the thickness of the uncompressed insulation material .
• the foraminous drum is provided with friction means for establishing sufficient adherence between the drum and the substrate to carry the substrate into, through and from the nip region.
• Such means can comprise a multiplicity of outwardly projecting nodules 19 which can be a part of .the drum, itself.
• the nodules can be comprised of rubber and are generally in the shape of elongated rectangles with rounded ends. They can be positioned on a rubber base which, in turn, is adhered to a flexible fabric which can be adhered to the exterior surface of the drum.
• the partially impregnated insulation pack 16 can then be drawn past another foam application station, which can be comprised of top foam discharge head 18 and second rotating foraminous drum 20 to produce fully impregnated insulation pack 22.
• any number of foam application stations can be employed for either the top or bottom (or both) of the porous substrate.
• the nip region 21 is defined by the positioning of the second foraminous drum adjacent the top foam discharge head.
• the foraminous drums can be driven by any suitable means, such as motors 23.
• the fully impregnated pack can then be passed through a dryer, such as radio-frequency dryer 24, which can remove water from the impregnated pack
• the impregnated, dried insulation pack can be passed through a curing station, such as curing oven 26, to produce cured insulation product 28.
• a curing station such as curing oven 26
• the dried, uncured insulation material can be molded using conventional wool molding techniques for such uses as automobile hoodliners and headliners.
• the foam discharge head is adapted with surface plate 32 across which the insulation pack is transported.
• the surface plate and other parts of the foam discharge heads are comprised of stainless steel, or some other wear-resistant, corrosion-resistant material.
• the surface plate is adapted with a plurality of discharge openings 34 for dispensing foam from the foam discharge head into the insulation pack.
• the discharge openings can comprise a single slot, not shown.
• the discharge openings comprise a plurality of holes, and preferably they are arranged in two or more rows, with the holes in one row being offset or staggered from the holes in another row.
• the foam discharge head can be spring-mounted with either hydraulic means, springs or pneumatic means 36 to accommodate solid or incompressible objects, such as glass slugs or density variations in the glass insulation pack, passing through the nip region between the foam discharge head and the foraminous drum.
• the pneumatic means also accomodate eccentricities in the foraminous drum.
• the foam discharge head can be mounted on hinged plate 42, the plate being pivotable about pivot pin 44.
• the urging means can be spring 36a which pushes up from base plate 46 to urge the foam discharge head toward the foraminous drum
• the foam discharge heads can be supplied with the binder foam from foamers 38a and 38b via any suitable means, such as hoses 40a and 40b.
• a mechanical foamer that has been found suitable for use for the invention is a 35 cm foamer manufactured by Oakes Corporation, Islip, New York.
• Such a foamer can produce the binder foam at a pressure within the range from about 280 to about 700 kilopascals, or higher.
• the foam pressure within the foam discharge head is limited only by the construction materials and the foam delivery capacity. Preferably the pressure is within the range of from about 21 to about 126 kilopascals, and most preferably within the range from about 35 to about 70 kilopascals.
• the pressure reduction from the foamer to the foam discharge head is provided by the hoses, and different size and length hoses can be used to produce the desired pressure drop.
• the pressure developed in the foam discharge head is dependent on the product produced and on the nature of the foam.
• the foam within the foam discharge head can have a density within the range of .01 g/cc to .05 g/cc or higher, and preferably, .03 g/cc (densities calculated at atmospheric pressure).
• foraminous surface 14a need not be a rotatable drum, but can follow a path which defines the nip region and seals the insulation pack against the foam discharge head.
• Scrim 48 can be directed by scrim transport rolls 50 to lie between foraminous surface 14b and the insulation pack as the pack passes through the nip region, as shown in FIGURE 4.
• the scrim would be advantageous to supplement the tensile strength of the insulation pack.
• a dry, 5-cm thick, 16 kilograms/meter glass fiber insulation pack having an initial binder content of 2 percent by weight was subjected to binder foam impregnation according to the principles of this invention.
• a foam binder material was prepared using an aqueous phenol-formaldehyde-urea resin with 2 percent by weight of Union Carbide's TERGITOL NP-10 as a foaming agent, and was applied to the insulation material with the apparatus of this invention using both a bottom and a top application.
• the minimum thickness of the nip region was about one cm
• the foam pressure in the discharge head was about 21 kilopascals
• the foam density was about .03 g/cc.
• the pressure applied to the insulation pack was about 3.75 kilograms per lineal cm.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Nonwoven Fabrics (AREA)
• Orthopedics, Nursing, And Contraception (AREA)
• Reinforced Plastic Materials (AREA)
• Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
• Manufacturing Of Printed Wiring (AREA)
• Chemically Coating (AREA)
• Absorbent Articles And Supports Therefor (AREA)

Priority Applications (6)

Applications Claiming Priority (3)

Publications (1)

Family

ID=27409843

Family Applications (1)

Country Status (10)

Cited By (3)

Families Citing this family (1)

Citations (4)

• 1983
  • 1983-05-16 AU AU17039/83A patent/AU560355B2/en not_active Ceased
  • 1983-05-16 EP EP83902058A patent/EP0111536B1/en not_active Expired
  • 1983-05-16 DE DE8383902058T patent/DE3364428D1/de not_active Expired
  • 1983-05-16 WO PCT/US1983/000760 patent/WO1984000041A1/en active IP Right Grant
  • 1983-06-13 IT IT21599/83A patent/IT1163514B/it active
  • 1983-06-13 CA CA000430232A patent/CA1205334A/en not_active Expired
  • 1983-06-13 NZ NZ204547A patent/NZ204547A/en unknown
• 1984
  • 1984-02-13 NO NO840512A patent/NO840512L/no unknown
  • 1984-02-13 DK DK0631/84A patent/DK63184D0/da not_active Application Discontinuation
  • 1984-02-14 FI FI840592A patent/FI840592A/fi not_active Application Discontinuation

Patent Citations (4)

Also Published As

Similar Documents

Legal Events