Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
  • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
  • B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
  • B32B5/26—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer another layer next to it also being fibrous or filamentary
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/06—Fibrous reinforcements only
  • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
  • B29C70/086—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers and with one or more layers of pure plastics material, e.g. foam layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/28—Shaping operations therefor
  • B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
  • B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D23/00—Producing tubular articles
  • B29D23/001—Pipes; Pipe joints
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D99/00—Subject matter not provided for in other groups of this subclass
  • B29D99/0046—Producing rods
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
  • B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/12—Layered products comprising a layer of synthetic resin next to a fibrous or filamentary layer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B38/00—Ancillary operations in connection with laminating processes
  • B32B38/08—Impregnating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C53/00—Shaping by bending, folding, twisting, straightening or flattening; Apparatus therefor
  • B29C53/56—Winding and joining, e.g. winding spirally
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
  • B29K2995/0003—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds having particular electrical or magnetic properties, e.g. piezoelectric
  • B29K2995/0005—Conductive
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
  • B29K2995/0012—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds having particular thermal properties
  • B29K2995/0013—Conductive
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
  • B29K2995/0018—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds having particular optical properties, e.g. fluorescent or phosphorescent
  • B29K2995/0026—Transparent
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/06—Rods, e.g. connecting rods, rails, stakes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/52—Sports equipment ; Games; Articles for amusement; Toys
  • B29L2031/5227—Clubs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/52—Sports equipment ; Games; Articles for amusement; Toys
  • B29L2031/5245—Rackets
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
  • B63B15/00—Superstructures, deckhouses, wheelhouses or the like; Arrangements or adaptations of masts or spars, e.g. bowsprits
  • B63B15/0083—Masts for sailing ships or boats

Definitions

• the present invention is concerned with the application of a finish, or surface layer, to an article made from a certain class of materials.
• finishes are applied to articles for many purposes. These purposes include coloring, patterning, and/or altering the surface texture of the article. These purposes also include sealing the surface of the article, improving the article's immunity to weather or other environmental agents, imparting strength and durability to the article, and generally altering selected physical properties of the article. Finishes may particularly serve to provide a surface layer which is distinguished from the underlying material by being harder, impervious to certain agents, colored, patterned, or otherwise differentiated from other regions of the article to which the finish is applied. Painting is well known as a common means of applying a finish to a surface in order to improve the properties of the surface.
• Paint and other common finishes are characterized by being adhered, or in adhesion, to the underlying material.
• Adhesion is the molecular attraction exerted between the surfaces of bodies in contact.
• a body having an adhered finish, for example paint is characterized in that at some regions sufficiently distant from the surface there exists only the material of the body whereas at the uppermost regions of the surface there exists only the paint.
• Adhesion is to be contrasted with cohesion, meaning molecular attraction by which the particles of a body are united throughout the mass.
• Articles made of the advanced composite materials are widely used in exceedingly demanding applications. These applications include aircraft and spacecraft components such as fuselages, ailerons, spoilers, flaps, structural sections, doors, rotor blades, rotor shafts, and fuel tanks. These applications further include vehicular components such as body panels, structural members, shafts, connecting rods, springs, and fuel tanks. These applications further include boat and ship components such as hulls, masts, booms, and winches. Finally, the composite materials find wide application in sporting goods such as fishing rods, tennis rackets, archery equipments, skis and ski poles, protective clothing and helmets, vaulting poles, and golf clubs. In all these applications the stringent requirements made on an article formed of advanced composite material are likewise made upon the finish of the article. The finishes commonly adhered to such surfaces have proven to exhibit problems in meeting such stringent requirements.
• the present invention is embodied in a method of producing high performance finishes to articles containing resin, such as articles made from advanced composite materials. Finishes produced in accordance with the present invention color, pattern, texture, protect, and/or alter the mechanical, thermal, light reflectivity, or electrical properties of articles made from resin.
• a sheet through which resin may pass such as by permeating, is applied (for example by wrapping or laying it on) to the surface of an article containing resin.
• the sheet is held in compressive contact with the article (for example by wrapping it with tape or by encasing the sheet and article in a vacuum bag or mold) while the epoxy in the article is cured.
• the article is typically cured thermally, i.e., the sheet-covered article is placed in an oven.
• a sufficient amount of resin exudes from the resin-containing article and passes through the sheet so as to form an exterior shell of cured resin.
• the cured resin shell envelopes the sheet and the article.
• the cured resin of both the article and shell is in cohesive contact through the sheet.
• the preferred embodiment of a finishing method in accordance with the present invention employs a sheet which bears (and which is preferably impregnated with) a resin that is compatible with the resin within the article, and that is advantageously the same resin.
• the preferred method proceeds identically to the basic method.
• the cured resin shell is made from resin that arose from both the resin-containing article and the resin-impregnated sheet.
• the sheet below the shell may be advantageously colored, patterned, and/or textured. It imparts a corresponding color, pattern, and/or slight texture (detectable to a limited extent through the resin shell) to the finished article. Furthermore, the sheet material possesses selectable physical and mechanical properties, particularly including reflectivity and conductivity and tensile strength, which are imparted to the composite, finished, article after curing.
• the overlay of sheet material is made from resin pre-impregnated fabric. It is preferably an epoxy resin impregnated cloth made from either synthetic fibers (which may additionally be coated with metal) , natural fibers, or from metal or ceramic filaments.
• the underlay, or article body is made from fiber-reinforced resin material. It is preferably made from epoxy resin that is reinforced with fibers of graphite, glass, or aramid, or with metal or ceramic filaments.
• the resin within the underlay is preferably identical to the resin within the overlay, and is normally epoxy resin or other readily available types of thermal curing resin.
• the preferably resin-impregnated overlay (e.g., the resin pre-impregnated fabric) will not merely adhere to the underlay of material that is preferably impregnated with thermal curing resin (e.g., fiber-reinforced resin material) but will cohesively bond thereto.
• thermal curing resin e.g., fiber-reinforced resin material
• a resin-impregnated fabric is patterned to the contours of a surface of a resin-impregnated article.
• the patterned fabric is then applied, for example by wrapping or laying it on, as an overlay to the surface of the article.
• the applied fabric is then compacted to the surface of the article, for example by wrapping with tape under tension or by the application of compressive force.
• the resin-impregnated article with the resin-impregnated fabric applied thereto is cured in an oven.
• the tensioned tape, or a compressive force generated by a vacuum bag or mold maintains the article under pressure during the curing and defines its contours.
• the sheet material is perforated with these apertures in the form of pinholes or slits either before or after application to the article's body.
• the sheet material may not exhibit apertures, and may instead be selectively applied to the underlying article body — for example in narrow strips at slight separation — so as to present a number of points generally in the form of cracks wherein passages exist through the overlay.
• color, markings, patterns, texture, and other visual and tactile properties may generally be selectively imparted to the surfaces of articles made from resin-containing materials, including articles made from advanced composite materials. These properties are imparted at lesser weight and at lesser complexity, potentially reducing cost, than obtaining these same properties, if they can be obtained at all, by gel coat or paint.
• the present invention is further generally adaptable to realizing a finish for resin- impregnated articles that possesses controllably selectable mechanical attributes.
• a finish for resin- impregnated articles that possesses controllably selectable mechanical attributes.
• the finish is of wholly compatible mechanical characteristics with the article. It is highly uniform with well-controlled mechanical properties.
• the finish can generally be made either inconsequential to the mechanical performance of the article, or of significant mechanical effect, as is desired and as is obtained by a particular choice of the bonded fabric.
• Figure 2 is a cross-sectional view, taken along aspect line 2-2 shown in Figure 1, showing the composite construction of the golf club shaft shown in Figure 1.
• Figure 3 consisting of Figure 3a through Figure 3r, shows the process of manufacture of a first sample item, a golf club shaft, in accordance with one preferred embodiment of the method of the present invention.
• Figure 4 consisting of Figure 4a through Figure 4k, shows the manufacture of a second sample item, a tennis racket, in accordance with another preferred embodiment of the method of the present invention.
• a composite article produced in accordance with the present invention generally exhibits the appearance of having a surface layer integrally upon and bonded to a more extensive underlay, or physical body.
• the composite article is not laminated because the overlay is not adhesively bonded to the underlay, or applied thereto, but is rather formed integrally therewith.
• a resin shell of the overlay is cohesively bonded to resin within the underlay. Particularly, the cohesiveness is so great that the exterior resin molecules of the composite body are in chained molecular contact with like resin molecules deep within the interior of the body.
• a sheet, or overlay exists at or slightly below the surface of the composite article. This sheet is completely permeated with (or in the case of impermeable sheet material surrounded by) the resin of the composite body. It might thus alternatively be considered that the present invention is directed to the submerging of a sheet completely within resin at or near the surface of a resinous article.
• the substantial mass, and physical properties, of the composite articles in accordance with the present invention are normally principally resultant from the underlay, the overlaid sheet at the surfaces of such articles selectively imparts desirable features to the surfaces and to the articles.
• a shaft of fiber reinforced thermosetting resin is cohesively bonded by heat and pressure to a fabric impregnated with a compatible resin, normally a woven synthetic or natural fiber cloth exhibiting voids which are impregnated with the identical epoxy resin.
• the cloth is particularly preferred to be nylon or polyester cloth upon which metal has been deposited in vapor form, creating thereby a brilliantly colored and highly lustrous cloth.
• the composite, cohesively bonded, hard-shelled golf club shaft so formed has a brilliantly colored, slightly textured, and lustrous exterior appearance which is characteristic of the cloth.
• the composite shaft possesses the precise dimensions, controlled stiffness, and high durability desired in a graphite fiber golf club shaft.
• An equivalent construction at a somewhat larger scale produces poles for pole vaulting, and at a considerably larger scale produces masts and booms for sailboats.
• Another particular preferred application of the present invention is in composite structural panels, made from resin-containing materials, for use in aircraft, vehicles, boats, and the like.
• the color, markings, patterns, texture and other visual and tactile properties of these composite panels may generally be established in accordance with the type of sheet that is cohesively bonded at the panels' surfaces.
• the desired properties are generally imparted at lesser weight, at lesser complexity (potentially reducing cost) , and at higher and more uniform quality than obtaining these same properties, if they can be obtained at all, by gel coat or paint.
• selected physical properties of the panels' surfaces, such as resistance to penetration or cracking may also be enhanced by the surface or subsurface cohesive incorporation of sheets made either of armor cloth or other fabrics of high tensile strength.
• the thermal and light reflectivity and absorption of the panels may be altered, particularly by the use of thermal and/or light absorbing or reflecting sheets made from materials including metal fabrics.
• the overlaid sheet is made of electrically conductive material, and is preferably made from electrically conductive fabric, and is more preferably made from metal cloth.
• Alternative electrically conductive fabrics include nylon, polyester and other fibrous cloths, or ceramic cloth, that have a metal coating deposited thereon.
• FIG. 1 An example of a composite article produced in accordance with the present invention — a golf club shaft — is shown in Figure 1.
• the underlay of this composite article 10 is a fiber reinforced resin material, specifically, resin-impregnated graphite fibers 11.
• the resin-impregnated graphite fibers 11 are in the shape of a hollow tube, and are commonly referred to as a graphite or carbon fiber golf club shaft.
• Such a shaft may be produced in accordance with the teaching of UK Patent No. 1,261,541, the contents of which are incorporated herein by reference.
• a shaft or other object could be made from resin- impregnated glass fibers as is taught in U.S. Patent No. 2,934,345, the contents of which are also incorporated herein by reference.
• the shape, and type, of the underlaid fiber-reinforced resin material could be diverse and still be appropriate for combination with an overlay in accordance with the present invention.
• the body or shaft could also be made from resin-impregnated aramid fibers, resin-impregnated ceramic filaments, and diverse materials which are impregnated with thermosetting resin whether or not incorporating fibers.
• the composite article golf club shaft 10 has an overlay 12 that is preferably made of material impregnated with a resin compatible with and capable of bonding with the resin within the underlaid resin-impregnated graphite fibers 11.
• the overlay 12 preferably was first impregnated, or permeated, with this "compatible" resin prior to its cohesive bonding to the resin within underlay 11. If overlay 12 is not "preimpregnated” then it must be impregnated during the curing step.
• This resin typically epoxy resin
• the resin layer measures a thickness of approximately 2 to 10 mm above the fabric and provides a hard transparent shell to the composite article 10 through which the embedded fabric is visible. However, if desired, the thickness of the resin layer can be increased or decreased.
• the embedded fabric will, in accordance with its own texture, impart a slight texture to the surface of the composite article, or golf club shaft 10. This texture is slightly rough but is not abrasive.
• the natural color of the resin-impregnated graphite fibers 11 is black and shows in any surface regions not covered by the overlay. Otherwise, the surface of the composite article 10 is of lustrous bright color in all regions where the overlay of resin-impregnated metal- coated cloth has been applied.
• the composite article so formed is characterized in that the resin of the fabric and the resin of the article's body is completely cohesively co-mingled and contiguous throughout the composite article, with no discernible separation or joint between the underlay and the overlay in the cured article.
• Some resin will be upon the exterior of the article and fabric, and this resin provides a uniformly hard and smooth shell through which, when the resin is transparent or translucent, the fabric is clearly visible.
• the fabric may be colored and patterned, and may also, in accordance with its roughness and thickness, impart a slight texture to the surface of the composite article even though it is contained within a resin shell.
• the production steps illustrated in Figures 3a through 3f are conventional in the prior art.
• a carbon or graphite cloth 20 is available from many manufacturers including Torayca, hercules, Hexcel, SEP, and Textron.
• the graphite cloth 20 is illustrated to be preimpregnated with a resin in Figure 3b.
• the resultant product is called a prepreg, and is normally available directly from the manufacturer.
• the prepreg 21 is cut into patterned prepreg 21a, and wrapped about a mandrel 30 as shown in Figures 3d-3f.
• a linear tube, or shaft, is formed about the mandrel 30.
• the preparation of an overlay in accordance with one embodiment of the present invention is illustrated in Figures 3g-3j .
• the overlay 41 is typically made from a fabric 40 which is preferably a cloth.
• the cloth is generally made from nylon, polyester, metal, ceramic, or other type of woven or non-woven material.
• the cloth is usually not available pre-impregnated with resin.
• the preferred method for impregnating the fabric 40, or cloth is to apply a thin sheet of resin 50, already applied to a sheet of release paper 60, to one side of the fabric 40 while directly applying another sheet of release paper 60 to the other side of fabric 40.
• the sandwich of release paper, fabric, resin, and release paper is then put into a vacuum table (not illustrated) .
• the vacuum table (not illustrated) .
• SUBSTITUTESHEET is evacuated, and heat and pressure of approximately 15 pounds per square inch (psi) is applied to fully impregnate the fabric with the resin.
• a conventional resin-impregnating machine as shown in Figure 3h may be used to impregnate fabric with resin equivalently to the manner in which prepregs are impregnated (as previously illustrated in Figure 3b) .
• the fabric 40 is impregnated upon a vacuum table or in an impregnating machine as illustrated in Figure 3h, a resin- impregnated fabric 41 as illustrated in Figure 3i is produced.
• a single-ply of the pre-impregnated fabric is cut to a predeter ⁇ mined pattern 41a (as illustrated in Figure 3j) for application to the surface of the article.
• the patterned and resin pre-impregnated fabric 41a is applied to the uncured article body made from fiber-reinforced resin material 21a by being wrapped around such article body (as illustrated in Figure 3k) , or by being laid on the article body as the case requires.
• the applied resin-preimpregnated fabric overlay is precompacted to the article body. This may occur either by a tape wrapping under tension as shown in. Figure 31, or by the application of compressive forces.
• the tape may optionally be shrink tape which grasps more tightly when heated, but this is not necessary.
• the wrapped article is then cured in an oven as illustrated in Figure 3m.
• the wrapped article may alternatively be placed in a vacuum bag or a mold and cured in an autoclave oven.
• the essential point of the curing step is that adequate heat and temperature is applied for an adequate time so as to completely cure the resin throughout the entire wrapped article, and that the article is confined under pressure by the tape or the vacuum bag or the mold for the duration of this curing. It should be understood that this is the first time at which either the resin within the fiber-reinforced resin material 21a, or within the resin- preimpregnated fabric material 41a, has been cured.
• the resins within the fiber-reinforced resin material 21a, and within the resin-preimpregnated fabric 41a, are compatible, and are preferably identical.
• the resins are typically epoxy or other thermosetting resin.
• the resins within the fiber-reinforced material 21a, formed as a shaft typically wick through the overlay of resin-preimpregnated fabric 41a, flow out through the spiral wrappings of tape 70, and drip onto the floor of the oven.
• the exterior dimensions of the cured composite article, particularly its diameter, is determined by the compression of the tape 70 which is wrapped around the shaft.
• the interior diameter of the shaft 10 is determined by the mandrel 30.
• the resin-impregnated fabric material 41a may, or may not, have been chosen to significantly affect the mechanical properties of the finished article.
• the fabric In the case of a golf club shaft, the fabric is normally intentionally chosen so as to not significantly affect the strength, stiffness, and flexure of the finished article.
• resin-containing material including fiber- reinforced resin containing material used in structural panels for vehicles, ships, and aircraft, it may be desirable that the penetration, resistance, and/or strength of such panels be increased by choice of the fabric cohesively bonded within and at the outermost regions thereof.
• armor-type fabrics including the aramid and polyester fiber soft armors, can impart enhanced penetration and abrasion resistance to a body's surface.
• Certain other fabrics such as the graphite fabrics, which have extremely high tensile strength can impart crack resistance to surfaces, especially in conditions of stretching stress.
• fabrics like the metal cloths and the ceramic filament cloths can alter the thermal reflectivity, absorption, and heat tolerances of the surfaces of articles to which they are cohesively bound.
• FIG 4 A second preferred embodiment of a fabrication method in accordance with the present invention is illustrated in Figure 4, consisting of Figure 4a through Figure 4k.
• the article illustrated to be produced therein is a tennis racket.
• the second embodiment of a method in accordance with the present invention is directed toward cohesive bonding of a flexible sheet material which does not include voids and which consequently cannot be impregnated with resin.
• the basic principle of this embodiment rests in the step of providing a sufficient number of openings within the surface of the flexible sheet material so that resin will escape from the resin-containing body through such openings during curing and will form a hard shell upon the top of the sheet material and at the surface of the composite article.
• Steps illustrated in Figures 4a through 4c are conventional in the process of producing a tennis racket from fiber-reinforced resin material.
• Figure 4a illustrates a braided material, typically graphite-fiber reinforced braid, which is available from Torayca and other manufacturers.
• this braided material 80 is impregnated with resin 90 by simple immersion.
• the resin- impregnated braid material 81 is illustrated to be wrapped around a core 100, typically made of polyethylene foam, in order to form the substantial contour of a frame of the tennis racket.
• a substantially resin-impervious flexible sheet material 110 has a backing 120 applied as illustrated in Figure 4d.
• the material of the backing 120 is either the same as, or compatible with, the resin 90.
• This backing 120 may be applied in a machine similar to an impregnating machines as illustrated in Figures 4d and 4e, or may be applied simply by immersing the impermeable sheet material 110 within the backing material 120. It may be that the backing material 120 appears upon both sides of the sheet material 110, but this is neither necessary nor harmful if it does occur.
• a backed sheet material 121 illustrated in Figure 4g is produced.
• the sheet material 121 backed with a substance that is either the same as or compatible with resin of the article is wrapped about, or otherwise laid on, the article in a manner so that a multiplicity of openings are presented through the sheet material 121 to the body of the article. This may be accomplished by pre-perforation of the backed sheet material 121 as illustrated in Figure 4g with a great multiplicity of slits, pinhole apertures, or the like.
• any perforation may be postponed until the sheet material has been applied to the article, giving the article the appearance illustrated in Figure 4h.
• the perforations of the sheet material should be sufficiently numerous and closely spaced so as to allow resin to escape from the underlying resin- containing material 81 during the curing process (as illustrated in Figures 4i-j) so as to completely form a hard resin shell over the sheet material in the finished item.
• the perforations can be more numerous, and/or individually larger, and/or more closely spaced than this minimal level as is desired, but with attendant impact upon the visual and essential mechanical characteristics of the finished item.
• the perforations can usually be made sufficiently small so that they are scarcely noticeable to the naked eye in the completed composite article.
• the core 100 material with the resin-impregnated braid 81 wrapped thereabout, and with the backed sheet material 121 still further wrapped about this structure is placed into a mold 130 as illustrated in Figure 4i.
• the curing under heat in the mold as illustrated in Figure 4j is usually conducted while pressurized air is supplied from air source 140 to one end of the core 100 while the other end of the core 100 is blocked airtight.
• a cross-section of the tennis racket article so produced, taken at the juncture of the handle to the frame of the racket, is shown in Figure 4k.
• This cross-sectional view reveals that the structure and shape of the composite article has assumed the shape of the mold, with the flexible sheet material 121 disposed slightly below a surface of hard resin.
• the flexible sheet material 121 may impart colorations, patterns, and/or visual, tactile, or mechanical properties to the finished article.
• nearly any flexible sheet, whether fabric or not, may be embedded, and cohesively bonded, at the surface of a resin-containing body. At this surface location the sheet can impart specialized properties to the body as required.
• the color, pattern, texture, penetration resistance, tensile strength, thermal and light reflectivity and absorption, and enhanced immunity to selected chemical agents may all be selectively addressed by sheet at, or proximate to, the surface of a resin-containing body.
• a sheet or fabric material may be chosen that will obtain better results at less weight and cost than would alternatively be obtained by the application of paint gel coat to a cured resin-containing body.
• properties can be obtained by a surface cohesive bonding of a sheet in accordance with the present invention wherein these properties are not even realizable by adhesion of other finishes to the cured body.
• the cohesive bonding of electrically conductive, metallic cloth will allow the establishment of electrical conductivity at the surface of a resin-containing body which is otherwise electrically insulating. This property is particularly useful in aircraft for the dissipation of static electricity amongst and through the panels of the aircraft, and for the channeling of electrical current resultant from lightning strikes.
• thermosetting resin impregnating the underlaid may be of a different color than either the overlaid sheet material or the resin impregnating the overlaid material.
• the predominant color of the composite material will be the different color. Color striations and gradient variations may also be obtained.
• the overlaid material is substantially light colored and the resin impregnating this overlaid material is clear.
• the present invention should be perceived to deal broadly with the integration of sheet material, particularly including fabrics, into the surface regions of the resin-containing bodies. Accordingly, the present invention should be defined by the following claims, only, and not solely by those preferred embodiments within which the present invention has been taught.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Composite Materials (AREA)
• Combustion & Propulsion (AREA)
• Ocean & Marine Engineering (AREA)
• Laminated Bodies (AREA)
• Moulding By Coating Moulds (AREA)
• Adhesives Or Adhesive Processes (AREA)

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• 1989
  • 1989-11-21 KR KR1019920701221A patent/KR960011751B1/ko not_active IP Right Cessation
  • 1989-11-21 JP JP90507448A patent/JPH05504104A/ja active Pending
  • 1989-11-21 AU AU56366/90A patent/AU652538B2/en not_active Ceased
  • 1989-11-21 EP EP19900907610 patent/EP0501959A4/en not_active Withdrawn
  • 1989-11-21 WO PCT/US1989/005348 patent/WO1991007281A1/en not_active Application Discontinuation

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