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EP-4052768-B1 - BALL AND METHOD FOR ITS MANUFACTURE

EP4052768B1EP 4052768 B1EP4052768 B1EP 4052768B1EP-4052768-B1

Inventors

  • Le, Huu Minh Tru
  • Nürnberg, Hans-Peter

Dates

Publication Date
20260513
Application Date
20160527

Claims (13)

  1. Ball (100), in particular a football, comprising: a. particles of expanded thermoplastic polyurethane, eTPU, which are connected to each other; b. at least one cavity (120); and c. a ball carcass (130) which surrounds the cavity (120), wherein d. the ball comprises a first layer (110) of the particles of eTPU which is provided as an outer shell of the ball (100), wherein e. the outer shell comprises a plurality of ball panels (117, 118, 119) with the particles of eTPU, and wherein f. the outer shell is arranged on the ball carcass (130); wherein the ball further comprises a plurality of layers (110, 180, 181, 182), wherein a thickness of the layers and / or a composition of the material of the layers and / or at least one process parameter for the manufacture of the layers varies between at least two of the plurality of layers; and wherein the ball further comprises a second layer (180) of non-expanded material which is arranged between the outer shell and the ball carcass (130).
  2. Ball (100) according to claim 1, wherein the outer shell comprises a thickness in the range of 0.5 mm - 10.0 mm, preferably in the range of 1.0 mm - 5.0 mm.
  3. Ball (100) according to claim 1 or 2, further comprising a plastic coating and / or a plastic foil material that is arranged on an outward facing surface (101) of the ball.
  4. Ball (100) according to one of claims 1 - 3, wherein an outward facing surface (101) of the ball and / or the plastic coating of claim 3 and / or the plastic foil material of claim 3 comprises a textured surface.
  5. Ball (100) according to one of claims 1 - 4, wherein the panels are glued to each other.
  6. Ball (100) according to one of claims 1 - 5, the ball having at least partially been manufactured from three-dimensionally pre-shaped ball panels.
  7. Method (400; 500) for the manufacture of a ball (100) according to one of claims 1 - 6, the method comprising the following steps: a. manufacturing a plurality of ball panels (117, 118, 119) which comprise the particles of expanded thermoplastic polyurethane, eTPU; and b. assembling the ball panels to at least partially form the ball (100).
  8. Method (400; 500) according to claim 7, wherein the manufacture of an individual ball panel comprises the step of connecting the particles to each other at their surfaces to form the ball panel.
  9. Method (400; 500) according to claim 8, wherein connecting the particles to each other comprises loading the particles into a mold and compression molding the particles within the mold to form the ball panel.
  10. Method (400; 500) according to claim 9, wherein the compression molding is performed at a temperature between 80° C and 200 °C, and preferably at a temperature between 100 °C and 180 °C, and particularly preferably at a temperature between 135 °C and 145 °C.
  11. Method (400; 500) according to one of claims 8 - 10, wherein the particles are fused at their surfaces by subjecting them to heat, in particular in the form of pressurized steam.
  12. Method (400; 500) according to claim 8, wherein the particles are fused at their surfaces by using high-frequency radiation, in particular radio-frequency radiation.
  13. Method (400; 500) according to claim 8, wherein the particles are connected to each other by using a bonding agent or a glue.

Description

1. Technical field The present invention relates to a ball, in particular a football, and a method for its manufacture. 2. Prior art Balls, such as footballs, basketballs or game balls for children of different construction as well as various methods for their manufacture are known from the prior art. With regard to a material with good rebound properties, the website http://www.azom.com/news.aspx?NewsID=37360 mentions a new expanded thermoplastic polyurethane material. The website mentions that tests under ISO 8307 (the ball rebound test) and under DIN 53512 show a rebound height as much as about 55 percent. With regard to different ball constructions, solid balls made of foamed material are available on the market as game balls for children and are also mentioned in patent specifications. CN 100506327 C discloses a solid, elastic ball with a core made of foamed polyurethane material. US 4,943,055 A discloses a ball for warming-up exercises, which comprises a metal core to increase the weight of the ball, an outer layer, and an intermediate layer containing a filling material, for example a polymer such as polyurethane. US 3,508,750 A and US 8,777,787 B2 disclose ball constructions using ball panels. More specifically, US 3,508,750 A discloses a ball for a game in which a plurality of ball panels are glued onto a carcass. US 8,777,787 B2 discloses a sports ball that may include a casing, an intermediate layer, and a bladder. In manufacturing the sport ball, a panel element of the casing and the bladder may be located in a mold, and a polymer foam material of the intermediate layer may be injected into an area between the bladder and the panel element. In addition, edges of panel element may be heat bonded to each other to join the panel elements and form seams of the casing. Further ball constructions are known from the publications US 5,865,697 A, GB 2,494,131 B, US 7,867,115 B2 and US 7,740,551 B2. US 5,865,697 A discloses a sports ball in which an intermediate layer with an elastomer material is arranged in a waffle-like arrangement between an outer layer of the ball and a bladder. GB 2,494,131 B discloses an inflatable ball with a first and a second half, wherein each half comprises reinforcing ribs either on an inner or outer wall and one half comprises a hole with a valve unit. US 7,867,115 B2 discloses toy balls with a light assembly comprised of a power source and a plurality of LEDs and a spherical skeletal structure comprising a plurality of segments. Finally, US 7,740,551 B2 discloses a bladder for an inflatable ball, the bladder including a structure for receiving an electronic component. US 6,106,419 A and WO 97/17109 A1 relate to a ball for use in playing games, especially to a pressureless ball, such as a pressureless tennis ball. Further prior art from is known from EP 1 424 105 A1, US 2012/177777 A1, EP 3 067 100 A1, the document "BASF Develops Expanded Thermoplastic Polyurethane" and US 2 131 756 A. US 2010/240479 A1 discloses a sport ball including a casing and a bladder located within the casing, the casing including a plurality of panel elements joined to each other with welds, and portions of the panel elements that include the welds projecting toward an interior of the ball. WO 2014/023794 A1 relates to a combination foam containing a matrix of polyurethane foam having foamed particles of thermoplastic polyurethane contained in the matrix. A disadvantage of some of the balls known from the prior art is that the processing cycle for their manufacture is complicated and long. Also, the surfaces of the balls according to the prior art may significantly deteriorate with time. The surface of conventional ball panels, or seams between the panels, may, for example, become brittle. This can lead to a decrease in their tear strength such that the balls can lose their shape and/or allow too much ingress of water into the material of the ball again decreasing their shape stability and leading to a deterioration of their physical properties. In addition, a further disadvantage of known balls is that they may lose their elasticity, in particular at low temperatures, or they need to be repeatedly inflated to maintain the desired in-use properties. 3. Summary of the invention It is therefore an objective of the present invention to provide improved balls like footballs or the like, which avoid or reduce at least some of the disadvantages of the prior art. In particular, the balls should comprise good elastic properties, even at low or high temperatures and maintain a high quality, both with respect to the physical properties and their appearance, over a long period of time. Furthermore, the complexity of ball manufacture should be minimized. The manufacture should also allow adjustment of the properties of the balls to the respective requirements dictated by use, in terms of weight, surface texture, aerodynamic properties, etc. These problems are at least partially solved by a ball for a game accor