WO1996003353A1

WO1996003353A1 - Bicomponent and long fiber product definition

Info

Publication number: WO1996003353A1
Application number: PCT/US1995/009217
Authority: WO
Inventors: Clarke Ii Berdan; Larry J. Grant; David P. Aschenbeck; Steven H. Williams; James W. Scott
Original assignee: Owens Corning
Priority date: 1994-07-25
Filing date: 1995-07-21
Publication date: 1996-02-08
Also published as: JPH10503557A; CA2194479A1; AU3139595A

Abstract

Numerous alternative methods of producing product definition in such thick, binderless wool packs (48) of long, single component, and particularly, bicomponent, glass fibers (16) are provided. The present methods are loosely grouped as those including a step which disturbs the fiber matrix, those including a step which adds an element to the fiber matrix, and those including a step of fusing fibers. The latter group of methods includes laser (94) and hot needle (90) fusing of fibers, while others include the addition of polymer fibers (96) and polymer material to long fibers (16) generally uniformly distributed in a binderless wool pack (48).

Description

BICOMPONENT AND LONG FIBER PRODUCT DEFINITION

TECHNICAL FIELD This invention relates to wool materials of mineral fibers and, more specifically, to insulation products of long glass fibers. The invention also pertains to the manufacture of insulation products made of long wool fibers.

PACKGRQUND ART Small diameter glass fibers are useful in a variety of applications including acoustical or thermal insulation materials. When these small diameter glass fibers are properly assembled into a lattice or web, commonly called a wool pack, glass fibers which individually lack strength or stiffness can be formed into a product which is quite strong. The glass fiber insulation which is produced is lightweight, highly compressible, and resilient. For purposes of this patent specification, in using the terms "glass fibers" and "glass compositions", "glass" is intended to include any of the glassy forms of mineral materials, such as rock, slag, and basalt, as well as traditional glasses.

The common prior art methods for producing glass fiber insulation products involve producing glass fibers from a rotary process. A single molten glass composition is forced through the orifices in the outer wall of a centrifuge or spinner, producing primarily straight glass fibers. The fibers are drawn downward by a blower, and conventional air knife and lapping techniques are typically used to disperse the veil to provide acceptable, generally uniform fiber distribution. The binder required to bond the fibers into a wool product and provide product integrity is sprayed onto the fibers as they are drawn downward. The fibers are then collected and formed into a wool pack. The wool pack is further processed into insulation products by heating in an oven, and mechanically shaping and cutting the wool pack. Once shaped, it is also desirable to highly compress wool packs to reduce shipping costs. Thus, it is also desirable for wool packs to exhibit rapid and reliable recovery from compression when unpacked for use.

To achieve desirable lattice properties such as generally uniform density, product integrity, and recovery from compression in wool insulating materials of glass fibers, it has been necessary to use fibers that are relatively short.

Long fibers are not used in wool products of glass fibers because of their tendency to excessive entanglement and the formation of ropes and strings. Thus, while long fibers display fiber-to-fiber entanglement even without binder, the nonuniformity of the resulting wool packs has long made them commercially undesirable. For purposes of this patent specification, in using the terms "short fibers" and "long fibers", the term "short fibers" is intended to include fibers of approximately 25.4 millimeters (1 inch) and less, and "long fibers" are intended to include fibers longer than approximately 50.8 millimeters (2 inches). Typically, a wool pack of short fibers produced by rotary fiberizing techniques will include some long fibers which, however, will comprise less than 10% of the wool pack.

Long fibers have different aerodynamic properties, and conventional lapping techniques have failed to eliminate, and rather tend to enhance, formation of ropes and strings in veils of long or semi-continuous fibers. Even when undisturbed, veils of long fibers tend to form ropes and strings as the veil slows in its descent to the collection surface. Despite movement of the collection surface, long glass fibers (as do undisturbed veils of short fibers) tend to pile up into nonuniform packs of fibers and unmanageable fiber accumulations. These nonuniform packs, characterized in part by roping, string formation, have long prevented significant commercial use of long fibers. The ropes of long fibers produce a commercially undesirable appearance and, more importantly, create deviation from the ideal uniform lattice and reduce the insulating abilities of the glass wool.

Short fiber insulation is not without its problems, however. Even short fibers that are straight form only a haphazard lattice, and some of the fibers lie bunched together. As a result, existing glass wool insulating materials continue to have significant nonuniformities in the distribution of fibers within the product.

A further problem with short fiber wools is that the binder used is expensive and has several environmental drawbacks. Many binders include organic compounds so that effluent from the production process must be processed to ameliorate the negative environmental impact of such compounds. In addition, the need for curing binder with an oven consumes additional energy, creating additional environmental cleanup costs. A still further problem with short-fiber products arises when the product is compressed. While the binder holds firm at fiber-to-fiber intersections while the glass fibers themselves flex, if the stress upon the fiber increases due to excessive compression, the fiber breaks. Thus, current insulation products are limited in the amount of compression possible while still attaining adequate recovery. Nonetheless, because long fibers are problematic in nearly all respects, commercial wool insulation products of glass fibers have long used only short straight fibers, despite the various drawbacks of short fibers in lattice nonuniformity, need for binder, and limited compressibility. Accordingly, the need remains for further improvements in wool insulation products to improve wool pack properties, reduce cost, and eliminate environmental concerns.

DISCLOSURE OF INVENTION The present invention satisfies that need by providing methods for further defining the shape of wool packs of long glass fibers, which methods generally maintain lattice uniformity, eliminate the need for binder, and result in a wool pack which displays significant compressibility and recovery desired for commercial products.

In accordance with the present invention, a wool pack of long glass fibers is provided including long fibers of a single glass composition, as well as fibers including two glass compositions which produce a non-linear, bicomponent fiber. Collection of long fibers into a wool pack is achieved by receiving a veil from a rotary fiberizer on a pair of high-speed rotating foraminous drum-like surfaces, separating the gases in the veil from the fibers by suction through the drum surfaces, and conveying the remaining fibers at high speed through a narrow gap between the drums to form a web. The drum surfaces are operated at high speeds to have a surface speed in the range of approximately 50% to 150% of the speed of the veil at the drums. The web is then distributed to form the wool pack. The fibers in the resulting wool pack are generally randomly and uniformly distributed. Alternatively, collection of long fibers into a wool pack may be achieved by receiving a veil produced by a rotary fiberizer on opposing first foraminous conveyor surfaces, removing the gases therefrom, and conveying the remaining fibers on second conveyor surfaces through a passage, while substantially maintaining fiber orientation established by the rotary fiberizer. The fibers in the resulting wool pack are oriented, interrelated in a generally spiral relationship.

The wool packs of long fibers produced in accordance with either method have a generally uniform distribution of fibers, and roping is generally absent. Such wool packs may be shaped initially by the forming process and packaged in plastic to provide product definition, or alternatively shaped in accordance with the methods disclosed in greater detail below. The methods for producing these wool packs are set forth in greater detail in co-pending applications, commonly assigned with the present application, U.S. Serial No. 08/236,067, filed May 2, 1994, entitled WOOL PACK FORMING PROCESS USING HIGH SPEED ROTATING DRUMS AND LOW FREQUENCY SOUND DISTRIBUTION, by Aschenbeck, and U.S. Serial No. 08/239,820, filed May 9, 1994, entitled DIRECT FORMING METHOD OF COLLECTING LONG WOOL FIBERS, by Grant, et al., both incorporated herein by reference.

As used herein, the phrase "wool pack of long fibers" refers to wool packs having a substantial proportion of long fibers, generally 50% or more by number or weight, but may also include wool packs having somewhat smaller percentages (greater than approximately 10%) of long fibers which, nonetheless, demonstrate the behavior of wool packs having higher percentages of long fibers.

Wool packs of long glass fibers provided in the present invention present unique problems related to product definition. The long fibers are entangled to a lesser degree than short fibers, and are produced without binder. While initial wool pack shape is provided as outlined above, and can be retained by packaging in film, greater definition in the wool pack for various products is desired. The thicker, binderless mats and wool packs of long fibers in the present invention present problems of product definition not previously fully addressed by the prior art. The present invention seeks to provide shape to wool packs including long fibers, particularly irregular, bicomponent fibers, which tend to form bunches, rather than readily adapting to shapes by the conventional application of binder combined with heat setting.

The methods of the present invention, thus, provide various alternative ways to produce product definition in such thick, binderless wool packs of long, single component, and particularly, bicomponent, glass fibers. The present methods are loosely grouped as those including a step which disturbs the fiber matrix, those including a step which adds an element to the fiber matrix, and those including a step of fusing fibers. It has been found, particularly with regard to irregularly shaped bicomponent fibers, that excessive entanglement induced in the surface of the wool pack has a negative impact on recovery. Further, it has been found that excessive disturbance of the fiber matrix beyond the surface, such as by needling, may cause otherwise entangled, irregularly shaped fibers in the wool pack to become straightened, loosing some of the desirable volume filling characteristics otherwise valued in the wool pack. Thus, care must be taken to preserve important commercial and functional characteristics while providing desired product definition.

The methods of the present invention which disturb the fiber matrix include hydroentanglement and air knife entanglement techniques which are adapted in accordance with the present invention for use with thicker fiberglass mats, i.e., those exceeding approximately 76 millimeters (3 inches) in thickness. Needle-punching is further disclosed herein using heated needles.

Those methods of the present invention which add an element to the fiber matrix include the injection of an adhesive string or thermoplastic string along a plurality of locations through the width of the wool pack, post-production addition of thermoplastic fibers to the wool pack which is still hot from initial forming, and stitching with fiber segments. These methods are generally less intrusive, and only portions or columns within the fiber matrix are disturbed.

The methods of the present invention which include fusing of fibers include the use of lasers to provide bonding at fiber-to-fiber connections, the fusing of surface areas of fibers with heated platens or heated needles, and the use of bicomponent fibers which include as one component a more easily fusible material, such as a glass of lower melting temperature, or other thermoplastic component. These latter methods are the least intrusive, involving only portions or columns of the fiber matrix, without significantly disturbing the matrix or introducing additional material into the wool pack.

These methods and other features and advantages of the present invention are set forth in greater detail in the drawings and detailed description below.

BRIEF DESCRIPTION OF DRAWINGS Figure 1 is a schematic view in side elevation of the method of the present invention.

Figure 2 is a schematic detail view in perspective of one embodiment of the present invention, performed at B in Figure 1.

Figure 3 is a schematic detail view in perspective of a device representative of several embodiments of the present invention, performed at B in Figure 1. Figures 4 A through 4D are schematic cross-sectional views of fibers in a wool pack interrelated in accordance with the present invention. MODES FOR CARRYING OUT THE INVENTION The method of the present invention may be used to define the shape of wool packs 48 of long glass fibers 16 as representatively shown in Figures 1 through 4D.

Referring to Figure 1, it may be seen in accordance with the present invention that the method begins by providing a binderless wool pack 48 of long glass fibers 16 in which the long glass fibers are generally uniformly distributed. A rotary fiberizing apparatus 11 is representatively shown. Stated broadly, defining the shape of the wool pack 48 of long fibers then includes compressing the wool pack 48 to a first thickness (as shown at B), and interrelating pluralities of long fibers 16 in specific portions of the wool pack 48. Thereafter, the pack is released (as indicated at C), whereupon the pluralities of long fibers 16 remain substantially interrelated in tension to maintain the wool pack 48 in a shape of desired thickness. The pluralities of fibers 16 are placed in tension by the tendency of the wool pack 48 to rebound to a less-defined bunch or pack having only its initial shape. When further compressed to a thinner, second thickness, as for shipment (indicated at D), the interrelationships established between fibers 16 ideally permit the fibers to flex, and the wool pack 48 recovers to its desired thickness when the further compression is relieved. Unlike prior art wool packs of short glass fibers interrelated with a generalized application of binder during fiberizing, the present invention discloses primarily post-production methods for interrelating specific portions of binderless wool packs 48 of long fibers 16.

In accordance with the method of the present invention, the pluralities of fibers 16 in the wool pack 48 may be either interrelated by additional entanglement, or may be interrelated by interconnection, or both. However, inducing substantial additional entanglement of fibers 16 on the surface of the pack, while providing good pack shape definition, has been found to adversely affect recovery of the pack after compression. Accordingly, it is preferred that compressing the wool pack 48 occurs substantially without relative motion between the two faces of the wool pack 48 and compression surfaces 84 in contact therewith, thus generally maintaining the interrelationships between long fibers 16 in contact with the compression surfaces 84. As shown in Figure 2, the compression surfaces 84 may be continuous belts or, alternatively, may be a plurality of smaller continuous belts in parallel or series, or a plurality of rollers oriented transversely to the direction of movement of the wool pack 48, or still other configurations or combinations of such elements. Particularly where the pack is stopped for compressing and interrelating fibers, the compression surfaces 84 may be provided by plates or other more rigid, non-moving surfaces. Regardless, the exact configuration and combination of the compression surfaces 84 is not critical to the present invention, so long as the compression surfaces 84 provide the needed compression and allow for performing the step of interrelating (through a configuration of gaps, spacing, openings) without producing unwanted surface entanglement in the wool pack 48.

The pluralities of long fibers 16 which are interrelated in the wool packs 48 in accordance with the present invention may be randomly distributed or generally oriented, for example, in a generally horizontal or spiral relationship. The long fibers 16 may be straight, made of a single glass, or may be irregularly shaped, bicomponent fibers. Further, the methods disclosed herein can be practiced separately or in combination to interrelate pluralities of fibers in a wool pack. While the methods of the present invention can also find use with other thermoplastic, polymer, and mineral fiber types, their application to binderless, long glass fibers is preferred.

In accordance with the present invention, several methods are provided which include fusing pluralities of long fibers 16 to provide interrelationships, and more precisely, interconnections, therebetween.

In the first such method, with the wool pack 48 compressed to a desired thickness, pluralities of long fibers 16 in specific portions of the wool pack 48 are interrelated by contacting at least a portion of one face of the wool pack 48 with a heated surface 86, and interconnecting a plurality of long fibers 16 in that portion of the wool pack 48 by heating the fibers to define the shape of the wool pack 48. Referring to Figure 2, the heated surfaces 86 are preferably applied to a continuous wool pack 48, and move with the pack to avoid excessive surface entanglement. Alternatively, the heated surfaces 86 may be applied to a stationary wool bait. The heated surfaces 86 may, for example, be actively heated platens, or may be passively heated by virtue of placement within an oven.

Heated surfaces 86 may be applied to a portion of the wool pack 48 along an edge, corner or face thereof, or in a pattern at such locations to shape the wool pack 48. Figure 2 shows a series of heated surfaces 86 moving with the wool pack 48 on a track structure (not shown) to representatively interconnect fibers 16 on the faces and edges of a wool pack 48 as indicated at portions 88. The heated surfaces 86 may be specially designed with a targeted power and temperature which determines the number of fibers 16 fused and the depth of penetration through the pack. The texture of the fused surface portions 88 can range from soft and pliable to stiff and hard.

Where the long fibers 16 are bicomponent fibers including two materials having different melting points, the heated surface may be heated to a temperature below the melting point of one material and above the melting point of the other, so that interconnection of the plurality of long fibers 16 is provided by melting or softening substantially one of the two materials of the bicomponent fibers.

A second method is provided in accordance with the present invention in which pluralities of long fibers 16 in specific portions of the wool pack 48 inward from the faces of a wool pack 48 are interconnected by positioning a heated surface therein. In this method, the heated surface is preferably a heated needle 90. With the wool pack 48 compressed to a desired thickness, contact with a plurality of long fibers 16 is made by inserting the heated needle 90 into the wool pack 48 from at least one face thereof. Such insertion defines at least a portion of the path of travel of the needle, and interconnection of a plurality of fibers 16 is performed along the path of travel of the needle. The path of travel of the needle further includes its path of retraction, as well as any lateral travel relative to the wool pack 48 while inserted therein. The needle thus forms internal interconnections between pluralities of binderless, long fibers 16. As shown in Figures 4A through 4D, the path of travel may cause those interconnections to be oriented in columns 100, along diagonal directions 102, or along short planar sections 104 if the heated needle 90 moves somewhat relative to the wool pack 48. Needle penetration may be varied in depth and angle, and may be applied from opposite sides of the wool pack 48, all of which depend on the particular requirements of the product being produced. Preferably a plurality of heated needles 90 are inserted at respective spaced locations throughout the wool pack 48 to provide product definition. Some possible patterns in this regard are shown in Figures 4A through 4D; however, there is no intent to limit the present invention to the illustrative patterns shown.

Again, where the long fibers 16 are bicomponent fibers of two materials having different melting points, the needle may be heated to a temperature below the melting point of one material and above the melting point of the other, so that interconnecting a plurality of long fibers 16 may be performed by melting or softening primarily one of the two materials of the bicomponent fibers.

Needles for use in accordance with this method are preferably smooth conductive metal needles, to minimize related fiber entanglement induced by their use, or could be textured to intentionally provide some level of fiber entanglement.

A third method is provided in accordance with the present invention in which pluralities of long fibers 16 are interconnected in specific portions of the wool pack 48 inward from its faces by applying laser light energy to heat portions of the fibers in the wool pack 48. Preferably a bank of laser light sources 92 (shown in Figure 3) are provided to apply laser light energy at respective spaced locations throughout the wool pack 48. The laser source 92 may be any conventional laser source capable of generating heat sufficient to initiate fusing between the fibers 16. The intensity (power) and beam width may vary depending on the wool pack 48 density, shape of fibers 16, and the product whose shape is being defined. Variation in the intensity and beam width affects the depth of penetration and the number of fibers 16 interconnected. As well, the glass fibers may include additives to make them opaque or more absorptive of the particular laser light being applied. The laser beam 94 may be applied in a perpendicular or angular orientation to the wool pack 48 to fuse pluralities of fibers 16 into columns 100 or diagonally oriented groups 102, and may enter from any face of the wool pack 48, as illustratively shown in Figure 4. This third method may also be used with bicomponent fibers, with the beam intensity targeted to affect one fiber component more than another or additives included for enhanced laser light absorption in one fiber component, and can be applied to provide fusing and interrelationships between fibers of many types in addition to the glass fibers preferred herein. In accordance with the present invention, several methods, denominated the fourth through sixth methods, are also provided which include a step of adding an element, such as polymer materials, to the fiber matrix to provide interconnections between pluralities of fibers 16. Thus, referring again to Figure 1, the fourth method of the present invention includes, prior to or concurrent with compressing the wool pack 48, the step of distributing polymer fibers 96 over a portion of the surface of the wool pack 48 (shown at A), and then heating the wool pack 48 (as shown at B) to melt or soften the fibers and provide an interconnection between pluralities of binderless glass fibers 16. The polymer chosen for the polymer fibers 96 may be any polymer material which is capable of interconnecting glass fibers when melted or softened, which is sufficiently strong to maintain such interconnection when in tension when the compressive force is released, and which is flexible during compression of the wool pack 48. Distribution of polymer fibers 96 over at least a portion of the surface of the wool pack 48 will provide interconnection of glass fibers 16 wherever those fibers are positioned during melting or softening, whether on or near a face of the wool pack 48, or inwardly disposed from a face. This method may further be practiced by distributing polymer fibers 96 sized to lodge substantially inward from a face of the wool pack 48. Both longer and shorter polymer fibers 96 may be interspersed to provide interconnection through the depth of the wool pack 48.

Alternatively, the fourth method may be practiced immediately after formation of the wool pack 48, which may emerge from forming processes at temperatures as high as approximately 93 to 204 degrees Centigrade (oC) (approximately 200 to 400 degrees Fahrenheit [oF]). Thus, the method may include providing a wool pack 48 having latent heat of production, and distributing polymer fibers 96 over a portion of the surface of the wool pack 48. Polymer fibers 96 may be distributed prior to or during the step of compressing (shown at B). Fibers of different sizes, may be applied to provide interconnections at different depths within the wool pack 48. In addition, the step of heating to further melt or soften the polymer fibers 96 may be either eliminated or performed (as indicated at B) to further melt or soften the polymer fibers 96.

A fifth method is provided which also includes a step adding an element to the wool pack 48 to provide interconnections between pluralities of fibers 16 therein. In the fifth method, the interconnection of the binderless long fibers 16 is provided by injecting streams of polymer material into a plurality of spaced locations throughout the wool pack 48, and forming a plurality of columns 100 including binderless long fibers 16 bonded together by such polymer material. The polymer material is preferably injected by a plurality of injection needles 98, as illustratively shown in Figure 3. The injection needles 98 may be positioned above the wool pack 48 or, preferably, inserted into the wool pack 48 from at least one face thereof. As with the heated needles 90 described above, insertion of the injection needles 98 defines at least a portion of a path of travel along which a stream of polymer material is injected. Such injection is preferably performed concurrently with compressing the wool pack 48 to a desired thickness. Again, the path of travel may cause the interconnections thus formed to be oriented in columns 100, along diagonal directions 102, or along short planar sections 104, as shown in Figures 4 A through 4D, if the injection needle 98 moves somewhat relative to the wool pack 48. Injection needle 98 penetration 5 may thus be varied in depth and angle, and may be applied from opposite sides of the wool pack 48, all of which depend on the particular requirements of the product being produced. As well, the injection needle 98 may expel polymer from its tip, or from at least one opening along its length, or both. The injection needles 98 are specially designed with targeted pressures and stream width which determines the number of fibers 16 bonded and the depth

10 of penetration through the pack.

A sixth method is provided which also includes adding an element to the wool pack 48 to provide interconnections between pluralities of fibers 16 therein. The sixth method comprises driving at least one fiber 106 intermittently into the wool pack 48 of long glass fibers 16 concurrently with the step of compressing. The thickness of the wool pack

15 48 is typically greater than 76.2 millimeters (mm) (3 inches). It is preferred in accordance with this method that a plurality of separate fiber segments 106 be driven into the wool pack 48 at spaced locations. So driven, the fibers 106 tend to deform, and otherwise interrelate with the binderless long fibers 16 so as to be locked into place by such deformation, thereby interrelating a plurality of fibers 16. Alternatively, stitching may be provided by a bank of 0 stitching needles, in like fashion as heated needles 90 in Figure 3. When the pack is compressed to a first thickness, the stitching needles introduce a glass or other material fiber through the pack. This produces columns 100 of fibers 16, interrelated by fibers 106 or a continuous fiber 108. The number of fibers 106 driven into the wool pack 48, and the spacing thereof however, are dependent on the amount of shape definition for the particular 5 product. Regardless, the spacing is such that the recovery of the overall wool pack 48 is not adversely affected by consequential entanglement produced in the wool pack 48. Moreover, the driven fiber 106 or stitched, continuous fiber 108 results in a rigid column in tension and a flexible column in compression. The thread or fiber 106 or 108 is specially designed with a fineness to resist heat flow and a strength to maintain top-to-bottom communication in the 0 pack.

Finally, a third group of methods is provided in accordance with the present invention, which includes a step which disturbs the fiber matrix of the wool pack 48 to provide interconnections between the pluralities of fibers 16. These methods include hydroentanglement and air entanglement methods adapted to the thick wool packs 48 of long fibers 16 presented by the present invention. In particular, the eighth method interrelates the long fibers 16 by injecting a high-velocity, low-volume stream of fluid through the wool pack 48 at spaced locations, concurrently with compressing the wool pack 48 to a desired shape. This may be understood by referring to Figure 3, and substituting water jets for laser beams 94. The fluid is preferably water, but may alternatively be steam, air, other gases or combinations thereof. The stream of fluid drags individual fibers 16 to a new location within the wool pack 48 and results in the entanglement of those fibers 16 with others in the area. After the wool pack 48 is released, the finished product attains the desired shape as a result of the entangled fibers. The volume of fluid used and the pressures with which it is injected are dependent on fiber diameter, product density, and product thickness.

The various methods noted above provide desired interrelationships between pluralities of fibers 16 in wool packs 48 to provide additional shape and product definition thereto. Practice of the methods will vary depending on the product being produced. Nonetheless, the methods share the common end of addressing the unique problems presented by binderless wool packs 48 of long fibers 16, and in particular, irregularly shaped, bicomponent fibers. While certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes in the method and system disclosed herein may be made without departing from the scope of the invention, which is defined in the appended claims.

Claims

CLAIMS 1. A method for defining the shape of binderless wool packs of long glass fibers comprising: providing a wool pack of long glass fibers wherein said long glass fibers are generally uniformly distributed; defining the shape of said pack of long fibers including performing the steps of: compressing at least a portion of said wool pack to a first thickness; and interrelating pluralities of long fibers in specific portions of said wool pack; and releasing said pack from compression; whereby said pluralities of long fibers remain substantially interrelated in tension to maintain said wool pack in a shape of desired thickness.

2. The method of claim 1 wherein said step of interrelating pluralities of long fibers includes interconnecting long fibers.

3. The method of claim 1 wherein said step of compressing includes contacting at least two faces of said wool pack with compression surfaces, and generally maintaining the interrelationships between long fibers in contact with said compression surfaces.

4. The method of claim 1 wherein said step of interrelating is performed during said step of compressing.

5. The method of claim 1 further comprising, after the step of interrelating, the step of further compressing said wool pack into a second thickness.

6. The method of claim 1 wherein said step of providing a wool pack comprises providing a wool pack wherein said long glass fibers comprise more than approximately 20% of the fibers.

7. The method of claim 1 wherein said step of interrelating pluralities of long fibers in specific portions of said wool pack comprises: contacting at least a portion of one face of said wool pack with a heated surface; and interconnecting a plurality of long fibers in said portion by heating said fibers; thereby further defining the shape of said wool pack.

8. The method of claim 7 wherein said portion comprises a portion of at least one edge of said wool pack.

9. The method of claim 7 wherein: said long fibers are bicomponent fibers comprised of two materials ■ having different melting points; and the step of contacting comprises contacting at least a portion of one face of said wool pack with a heated surface having a temperature below the melting point of one material and above the melting point of the other; and the step of interconnecting comprises interconnecting said plurality of long fibers by at least softening one of the two materials of said bicomponent fiber.

10. The method of claim 1 wherein said step of interrelating pluralities of long fibers in specific portions of said wool pack comprises: contacting portions of fibers inward from the faces of said wool pack by positioning a heated surface therein; and interconnecting a plurality of long fibers inward from the faces of said wool pack by heating said portions of said fibers with said heated surface; thereby further defining the shape of said wool pack.

11. The method of claim 10 wherein: said step of contacting is performed by inserting at least one heated needle into said wool pack from at least one face thereof, defining at least a portion of the path of travel of said needle; and said step of interconnecting is performed along said path of travel of said needle.

12. The method of claim 11 wherein: said long fibers are bicomponent fibers comprised of two materials having different melting points; and the step of contacting includes heating said needle to a temperature below the melting point of one material and above the melting point of the other; and the step of interconnecting comprises interconnecting said plurality of long fibers by at least softening one of the two materials of said bicomponent fibers.

13. The method of claim 1 wherein said step of interrelating pluralities of long fibers in specific portions of said wool pack comprises: heating portions of fibers in said wool pack by applying laser light energy to said fibers; and interconnecting a plurality of long fibers in said wool pack by heating said portions of said fibers with said laser light energy; thereby further defining the shape of said wool pack.

14. The method of claim 13 wherein said step of applying laser light energy is performed in a plurality of spaced locations throughout said wool pack.

15. The method of claim 14 wherein: said step of applying laser light energy is performed in a direction generally perpendicular to at least one face of said wool pack; and said step of interconnecting is performed with portions of said fibers positioned along lines generally perpendicular to one face of said wool pack.

16. The method of claim 1 wherein said step of defining includes: distributing polymer fibers over a portion of the surface of said wool pack; and said step of interrelating comprises heating said wool pack.

17. The method of claim 16 wherein said step of distributing polymer fibers includes distributing polymer fibers sized to lodge substantially inward from a face of said wool pack.

18. The method of claim 1 wherein: said step of providing comprises providing a wool pack having latent heat of production; and said step of defining includes distributing polymer fibers over a portion of the surface of said wool pack.

19. The method of claim 1 wherein said step of interrelating comprises: injecting streams of polymer material into a plurality of spaced locations throughout said wool pack; and forming a plurality of columns including long fibers bonded together by said polymer material.

20. The method of claim 19 wherein said step of injecting is performed with a plurality of injection needles, and includes: inserting at least one of said injection needles into said wool pack from at least one face thereof, defining at least a portion of the path of travel of said injection needle; and injecting a stream of polymer material along said path of travel of said injection needle.

21. The method of claim 1 wherein said step of interrelating comprises driving at least one fiber intermittently into said wool pack of long glass fibers concurrently with said step of compressing.

22. The method of claim 21 wherein said step of driving comprises driving a plurality of separate fiber segments at spaced locations into said wool pack.

23. The method of claim 1 wherein said step of interrelating comprises injecting a high-velocity stream of fluid through specific portions of the wool pack at spaced locations, and performing said step of interrelating concurrently with said step of compressing.

24. The method of claim 23 wherein said fluid is selected from the group consisting of water, steam, air or combinations thereof.

25. A method for defining the shape of wool packs of fibers comprising: providing a wool pack of fibers; defining the shape of said pack of fibers including performing the steps of: compressing at least a portion of said wool pack to a first thickness; and interrelating pluralities of fibers in specific portions of said wool pack by: heating portions of a plurality of fibers in said wool pack by applying laser light energy to said portions of said fibers; and interconnecting portions of said plurality of fibers in said wool pack by softening said portions of said fibers with said laser light energy; and releasing said pack from compression; whereby said pluralities of fibers remain substantially interrelated in tension to maintain said wool pack in a shape of desired thickness.

26. The method of claim 25 wherein said step of providing a wool pack comprises providing a wool pack having long fibers wherein said long fibers comprise more than approximately 20% of the fibers.