Shoe comprising a sole of a thermoplastic material and a method for use in manufacturing such a shoe

Abstract

The present invention pertains to a new shoe comprising a sole of a thermoplastic material adhered to an upper shoe with a hot melt adhesive that is applied between the sole and the upper shoe, wherein the hot melt adhesive is fused with the thermoplastic material. Advantageously, the fusion is brought about by heating the hot melt adhesive to a temperature THM such that it softens, heating the second body such that the thermoplastic material that has a melting temperature TM obtains a temperature T SUB below T M while making sure that (T HM +T SUB )/2 is equal to or higher than (T M −10° C.).

1 . A shoe comprising a sole composed of a thermoplastic material adhered to an upper shoe with a hot melt adhesive that is applied between the sole and the upper shoe, wherein the hot melt adhesive is fused with the thermoplastic material. 
     
     
         2 . A shoe according to  claim 1 , wherein the sole comprises a foamed composition comprising a thermoplastic copolyester elastomer in an amount of 70 to 99 wt % based on the total amount of the foamed composition. 
     
     
         3 . A shoe according to  claim 2 , wherein the foamed composition comprises a thermoplastic copolyester elastomer in an amount of 70 to 99 wt % and a plasticizer in an amount of 1 to 30 wt % based on the total amount of the foamed composition. 
     
     
         4 . A shoe according to  claim 2 , wherein the thermoplastic copolyester elastomer comprises hard segments built up from polyester repeating units derived from at least one aliphatic diol and at least one aromatic dicarboxylic acid or an ester thereof, and soft segments chosen from the group consisting of aliphatic polyether, aliphatic polyester, aliphatic polycarbonate, dimer fatty acids and dimer fatty diols and combinations thereof. 
     
     
         5 . A shoe according to  claim 4 , wherein the hard segments are chosen from the group consisting of ethylene terephthalate (PET), propylene terephthalate (PPT), butylene terephthalate (PBT), polyethylene bibenzoate, polyethylene naphtalate (PEN), polybutylene bibenzoate, polybutylene naphtalate, polypropylene bibenzoate and polypropylene naphtalate and combinations thereof and the soft segments are chosen from the group consisting of aliphatic polyether, aliphatic polyester, aliphatic polycarbonate, dimer fatty acids and dimer fatty diols and combinations thereof. 
     
     
         6 . A shoe according to  claim 5 , wherein the hard segment is chosen from PBT or PET and the soft segment is chosen from the group consisting of polybutylene adipate (PBA), polyethylene oxide (PEO), polypropylene oxide (PPO), polytetramethylene oxide (PTMO), PEO-PPO-PEO and combinations thereof. 
     
     
         7 . A shoe according to  claim 1 , wherein the upper shoe comprises a layer of textile material that is contiguous with the sole. 
     
     
         8 . A shoe according to  claim 7 , wherein textile material comprises polymeric yarns. 
     
     
         9 . A shoe according to  claim 8 , wherein polymeric yarns comprise polyester polymer. 
     
     
         10 . A shoe according to  claim 1 , wherein the hot melt adhesive comprises a polymer selected from the group consisting of (co)polyurethane(s), (co)polycarbonate(s), (co)polyester(s), (co)polyamide(s), (co)poly(ester-amide(s)), mixtures thereof and/or copolymers thereof. 
     
     
         11 . A shoe according to  claim 10 , wherein the hot melt adhesive comprises a (co)polyester. 
     
     
         12 . A shoe according to  claim 1 , wherein the hot melt adhesive is semi-crystalline, preferably having a melting enthalpy between 1 and 80 J/g. 
     
     
         13 . A method of assembling a workpiece comprising a first body mechanically connected to a second body by adhering the first body to a surface of the second body, the second body being composed of a thermoplastic material that has a melting temperature T M , the method comprising:
 Heating a hot melt adhesive to a temperature T HM  such that it softens;   Heating the second body such that the thermoplastic material obtains a surface temperature T SUB  below T M ;   Applying the heated hot melt adhesive to the surface of the heated second body;   Applying the first body to the second body to form the workpiece;   Cooling the workpiece such that the hot melt adhesive hardens;   Wherein the temperatures are chosen such that (T HM +T SUB )/2 is equal to or higher than (T M −10° C.).   
     
     
         14 . A method according to  claim 13 , wherein temperatures are chosen such that (T HM +T SUB )/2 differs from T M  by a number of degrees chosen from the group consisting of −10, −9, −8, −7, −6, −5, −4, −3, −2, −1, 0, +1, +2, +3, +4, +5, +6, +7, +8, +9, +10, +11, +12, +13, +14, +15, +16, +17, +18, +19 or +20° C. 
     
     
         15 . A method according to  claim 13 , wherein the second body is heated such that the thermoplastic material obtains a temperature T SUB  that is at most X ° C. less than T M , X being chosen from the group that consists of 100, 90, 80, 70, 60, 55, 50, 45, 40, 35 and 30. 
     
     
         16 . A method according to  claim 13 , wherein the second body is heated in its entirety. 
     
     
         17 . A workpiece obtainable by a method according to  claim 13 .