TARGET FACE

Abstract: A laminar element (16) for use as a target face is composed of non-woven polymer fibres compressed and bonded to form a single layer of penetrable material which is resistant to water and dimensionally stable over a wide range of temperatures, flexible non-deformable and printable. Target indicia are formed on one face by any one of a wide range of printing techniques. The polymer may be TYVEK (Tm) by Dupont, Kevlar (Tm) or carbon fibre.

Description: TARGET FACE The present invention relates generally to target faces as used in a number of projectile sports, especially toxopholy and small arms shooting for sporting purposes. Known targets for such sporting purposes, in the case of toxopholy (more commonly known as archery) comprise a body of impact-absorbing material, conventionally known as a butt, to the front face of which is attached a removable target face printed with the target indicia usually (but not exclusively) conventional concentric circles. The butt is normally formed of straw or polymer foam and can be re-used many times. However, in use target faces suffer puncture damage and, of course, for competitive use, it is necessary to maintain a clear distinction between the entry points and therefore scores attributable to different competitors. Target faces are, therefore, readily removable and usually held to the front face of the butt by special pins. There are several governing bodies throughout the world which lay down strict requirements for archery target faces to be used in competitions. Prior art archery target faces, intended to be positioned on the front face of a butt, are formed of paper which is frequently laminated for example with an open polyamide mesh reinforcement having a mesh size of about 10mm. This reinforcement is primarily intended to prevent stretching or deformation of the target face which would cause changes in the shape and dimensions of the printed target indicia. Known paper target faces have a major disadvantage, however, in that they are not waterproof and this causes considerable problems in outdoor use, especially since many archery competitions take place out of doors. It is always inconvenient to have to discontinue a competition due to inclement weather and, of course, the disadvantage this places on competitors competing at the time is considerable. Similar problems arise in relation to target faces used in pistol and rifle shooting which, however, are usually printed on thin card and held in a frame spaced from an impact-absorbing material which, in this case, needs to be rather more robust than an archery butt in view of the greater kinetic energy of rifle and pistol bullets. The ideal properties of a removal target face can be listed as follows: first it must be tough durable and stable when exposed to ultraviolet radiation, yet be easily puncturable when struck by the intended projectile. It must also be capable of receiving indicia with well-defined edges to define the target area, and it must be completely stable, that is it must not be subject to any dimensional changes when experiencing variations in humidity or moisture. In particular, it must not swell upon being saturated nor shrink upon drying nor must it loose its structural integrity in either situation; moreover, it must not stretch or shrink within the range of working temperatures normally experienced, regardless of any humidity and/or moisture changes. The target image should have a non-reflective matt surface and, of course, because it is a consumable item it must not be too expensive. Various alternatives to the conventional paper target face have been tried without success. For example, plastic sheeting, although suitably puncturable and water proof, and although it can be printed, fails to match up to the requirements in several other respects, in particular, such material, especially polyvinyl chloride (PVC) shrinks and stretches with changes in temperature, and can crack under certain conditions; moreover, when used as an archery target, it has been found that arrows tend to pick up material from the target face on penetration, and when printed it tends to be too reflective. In addition, it is rather more expensive than paper, and even the quality of the printing can be poor, with ill-defined edges. For these reasons an alternative has been sought. According to the present invention, there is provided a lamina element for use as a target face, characterised in that it at least substantially comprises a piercable layer composed of a mesh of polymer fibres substantially non-deformable in the plane of the layer, bearing target indicia of water-resistant ink or dye. Although various polymers are suitable, the preferred polymer is high-density polyethylene (HDPE) which is found to have particularly suitable properties. The mesh of the piercable layer preferably comprises a non- woven polymer fibre layer. This may be presented as a substantially homogeneous single layer on which the target indicia are marked by printing or dyeing, or the layer may be part of a composite structure which will be described in more detail below. It has been found particularly advantageous if the selection of polymer fibre material and the ink or dye is such that the ink or dye impregnates the said non- woven material upon application, that it the ink or dye stains the fibres themselves rather than overlying the surface formed by the mesh. This ensures that the mesh layer remains "breathable", that is gas-permeable, and thus retains all of its properties unaffected by the ink or dye and allows the arrow or other projectile to pierce the layer upon impact without tearing. The present invention also comprehends the application techniques which will be described in more detail below. The said layer of non- woven polymer fibres may be rendered substantially non- deformable in the plane of the layer by treatment or by composition with an adjacent layer. It may, of course, be inherently non-deformable as a consequence of the production technique. The printed or dyed surface of the said layer is preferably a substantially non- reflective or matt surface. This is achieved by a suitable choice of inks or dyes for formation of the target indicia as will be described below. The said ink or dye of which the target indicia are formed is preferably a water- based material. In preferred embodiments of the invention the said layer is composed of a material not susceptible to shrinkage upon contact with water, upon drying out or upon exposure to solar radiation. In the preferred embodiment the said layer is at lest partly composed of TYVEK non- woven sheet material which is a non- woven flexible material made from HDPE fibres which are spun, randomly deposited and bonded by compression to produce a uniform layer about 0.19 mm thick with a density of about 60 gsm. This material has a non-reflective matt white surface on which target indicia can be printed. The said layer may, as mentioned above, be entirely composed of this material or may be partly composed thereof or of carbon fibre or KEVLAR (RTM) or carbon fibre mesh. Preferably the thickness of the said layer lies in the range 0.1 mm to 0.6 mm, preferably in the region of 0. 2 mm. Likewise, the density of the said layer preferably lies in the region of 30 gsm to 200 gsm, preferably between 50gsm and 70 gsm. A specific embodiment has a density of 60 gsm. Reinforcement of the said layer may be achieved by use of a backing layer of another material, preferably also in the form of a mesh of fibres. Although conventionally target faces are secured to a butt by means of pins, it is possible for the material of the present invention to have a layer of adhesive on one surface of the said layer to allow it to be secured to a butt by this adhesive. Suitable adhesives include pressure-sensitive low-tack materials. The present invention also comprehends a method of producing a target face comprising the steps of forming a web composed of a mesh of polymer fibres, applying a plurality of target indicia to one face of the web by printing or dyeing, and separating individual target faces from the web between adjacent target indicia. The target indicia are preferably applied to the web by flexographic or gravure printing, screen printing or web offset printing techniques. The inks utilised for these printing techniques are preferably water based inks having low-reflection properties and a degree of elasticity when dry (selected by choosing an appropriate polymer content) as to be sufficiently elastic to allow flexing of the target when being handled, and of impregnating the material. The method of the invention may also further comprise the step of perforating the web between adjacent target indicia and storing the thus-perforated web on a roll prior to separation of individual target faces therefrom. This allows a plurality of targets to be delivered for a competition on a roll, permitting convenient and easy storage and transport, and for the competition authorities to remove targets one at a time from the role for use. The targets may be individually numbered upon removal, or the printing technique may apply an identification number to each target. This assists in correlating the competitors with the targets. Each individual target face may be substantially rectangular, with circular indicia printed thereon, or the separation of individual target faces may remove from the web a circular element the size of which corresponds substantially (or slightly less than) the diameter of the butt to which the target face is intended to be attached in use. Embodiments of the present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an archery butt showing a target face of the invention in position ready to be secured thereto; and Figure 2 is a schematic diagram illustrating one embodiment of the method of the invention for forming target faces. Referring first to Figure 1 there is shown an archery butt generally indicated 11 of otherwise conventional form comprising a circular body 12 of compressed straw borne on tripod legs 13, 14 and 15. The front face of the butt 12 is covered with a target face 16 formed in accordance with the principles of the present invention and this can be secured in place by conventional face pins 17 shown only schematically in Figure 1. In order to meet the requirements of dimensional stability and resistance to water the target face 16 is composed of a single sheet of TYVEK (a registered trademark of Dupont) which is a non- woven flexible material made from HDPE fibres which are spun, randomly deposited and bonded together by compression to produce a uniform thickness sheet of about 0.1 mm having a density of about 60 gsm. As can be seen in the enlargement showing a portion of the edge region of the sheet 16, the random deposition of the fibres and their bonding together results in the ability of the material to resist deformation within the plane of the layer in all directions. Because it is not a woven mesh there is no preferential direction of stiffness and no risk of stretching on a diagonal or bias line as there would be with a woven mesh. In this embodiment the target face 16 is cut to a circular shape to match that of the butt 12, with the pin 517 being positioned at suitable intervals around the periphery. Alternatively, of course, a target face could be cut from a square or rectangular sheet of material (albeit printed with a circular target image) and the corners folded over the butt to be secured in position by pins fitted to the edge region or the rear face of the butt depending on how far around the corners of the target face pass when the target face is being fitted to the front of the butt. Figure 2 illustrates the major steps in the production of a target face in accordance with the principles of the present invention. The block 18 represents the formation of the fibres which are then passed between guide rolls 19, 20 which directs them towards a heating station 21 at which the fibres are raised to a temperature at which they will bond together upon compression. The roving thus formed and heated is passed between two compression rolls 23, 24 at which the fibres are bonded together to form a stable web 22 which is then rolled onto a storage roll 25. This, as shown by the arrow A is then passed to a printing and perforating station where the web 22 is drawn from the roll, passed between an offset printing set comprising a print roll 27, a counter roll 28 which applies pressure between the print roll and the web 22 and an image application roll 28 which receives ink from an inking roller 29 which dips into an ink bath 30. Surplus ink is removed from the inking roller 29 by a doctor blade 31. The image itself is borne on the transfer roller 28, and ink transferred to the print roll 27 in the desired pattern to be applied to the web 22. After printing the web 22 passes between a perforator roll 32 and counter roll 33 to a storage roll 34 which, when full, is removed and held in storage as represented by the arrow B in Figure 2. Sheets of TYVEK non- woven sheet material have a non-reflective matt white surface which, when printed with suitable water-based flexible inks will have a matt non-reflective image. The material is extremely strong and tear-resistant but can be penetrated by arrows without difficulty, the arrows penetrating between the fibres and causing displacement of these without rupture of any material and without pick up of material from the target face. The nature of the material is highly weather proof. It is not affected by contact with water and does not stretch or shrink over a wide range of temperatures. Although the present invention has been described with specific reference to an archery target, target faces for other purposes can be easily encompassed within its scope. A target face for use in pistol or riffle shooting may be formed from a matt white sheet of TYVEK non- woven sheet material having a slightly greater weight than the previous embodiment, say about 80 gsm, again comprising a single sheet of TYVEK non- woven sheet material. Such a sheet may be held in a frame without an adjacent backing, in front of a suitable absorbent material such as a sand bank or a wall of sandbags, such that projectiles having passed through the target are stopped in a conventional manner. Again, penetration of such a target face by a projectile does not result in tearing or rupture of the material, but rather lateral displacement of the fibres leaving a neat round hole accurately representing the point of impact of the projectile.

Claims: CLAIMS 1. A laminar element for use as a target face, characterised in that it at least substantially comprises a piercable layer composed of a mesh of polymer fibres bearing target indicia of water resistant ink or dye. 2. A laminar element according to Claim 1, characterised in that the mesh comprises a non- woven polymer fibre layer. 3. A laminar element according to Claim 1 or Claim 2, characterised in that it comprises a substantially homogeneous single layer. 4. A laminar element according any of Claims 1 to 3, characterised in that the ink or dye impregnates the said non- woven material. 5. A laminar element according to any preceding claim, characterised in that the said layer of non- woven polymer fibres is rendered substantially non- deformable in the plane of the layer by treatment on by composition with an adjacent layer. 6. A laminar element according to any preceding claim, characterised in that the printed or dyed surface of the said layer is a substantially non-reflective or matt surface. 7. A laminar element according to any preceding claim, characterised in that the said ink or dye of which the target indicia are formed is a water-based material. 8. A laminar element according to any preceding claim, characterised in that the said layer is composed of a material not susceptible to shrinkage upon contact with water, upon drying out or upon exposure to solar radiation. 9. A laminar element according to any preceding claim, characterised in that the said layer is at least partly composed on non-woven TYVEK (RTM) sheet material. 10. A laminar element according to any preceding claim, characterised in that the said layer is composed entirely of non- woven TYVEK (RTM) non- woven sheet material. 11. A laminar element according to any of claims from 1 to 9, characterised in that the said layer is at least partly composed of non- woven KEVLAR (RTM) or carbon fibre, or a KEVLAR or carbon fibre mesh. 12. A laminar element according to any preceding claim, characterised in that the thickness of the said layer lies in the range of 0.1 mm to 0.67 mm, preferably 0.2 mm. 13. A laminar element according to any preceding claim, characterised in that the density of the said layer lies in regions of 30 gsm to 200 gsm, preferably between 50 gsm and 70 gsm. 14. A laminar element according to any preceding claim, characterised in that the said layer is reinforced with a backing layer of another material, preferably in the form of a mesh. 15. A laminar element according to any preceding claim, characterised in that one surface of the said layer has a layer of adhesive thereon. 16. A laminar element according to any preceding claim, characterised in that the said layer is composed of a heat-bonded and compressed non- woven mesh of polymer fibres. 17. A method of producing a target face, characterised in that comprises the steps of forming a web composed of a mesh of polymer fibres, applying a plurality of target indicia to one face of the web by printing or dyeing techniques, and separating individual target faces from the web between adjacent target indicia. 18. A method according to Claim 17, characterised in that the target indicia are applied to the web by one of flexographic printing, gravure printing, screen printing and web offset printing. 19. A method according to Claim 17 or Claim 18, characterised in that it further comprises the steps of perforating the web between adjacent target indicia, coiling the thus-perforated web on a roll and storing the roll prior to separation of individuals target faces therefrom.

Inventors: HOWELL DAVID ALFRED THOMAS, HOWELL, DAVID, ALFRED, THOMAS
Applicants: HOWELL DAVID ALFRED THOMAS, HOWELL, DAVID, ALFRED, THOMAS
Application year: 2001
Main classification: F41J1
IPC codes: F41J1