SHOE UPPERS

Abstract

The present invention relates to an upper for a footwear article, said upper comprising at least one panel having at least one layer made from a composition comprising a fluorinated thermoplastic polyurethane polymer.

Claims

1. An upper, for a footwear article, comprising at least one panel having at least one layer (E) made from a composition (C), wherein composition (C) comprises at least one F-TPU polymer, wherein F-TPU polymer is a fluorinated polyurethane comprising recurring units derived from: monomer (a), wherein monomer (a) is at least one diol selected from the group comprising poly-ether type diol, poly-ester type diol, polybutadien-diol and polycarbonate-diol; monomer (b), wherein monomer (b) is at least one hydroxy-terminated (per)fluoropolyether polymer; monomer (c), wherein monomer (c) is at least one aromatic, aliphatic or cycloaliphatic diisocyanate; and monomer (d), wherein monomer (d) is at least one aliphatic, cycloaliphatic or aromatic diol having from 1 to 14 carbon atoms.

2. The upper according to claim 1, wherein said at least one monomer (a) is selected from the group consisting of poly(ethylene)glycol, poly(propylene)glycol, poly(tetramethylen)glycol (PTMG), poly(1,4-butanediol)adipate, poly(ethandiol-1,4-butanediol) adipate, poly(1,6-hexandiol-neopentyl)glycol adipate, poly-caprolactone-diol (PCL) and polycarbonate-diol.

3. The upper according to claim 1, wherein said at least one monomer (b) is a hydroxy-terminated (per)fluoropolyether polymer comprising a (per)fluoropolyoxyalkylene chain (R.sub.pf) having two chain ends, wherein one or both chain ends terminates with at least one OH group.

4. The upper according to claim 3, wherein at least one chain end of said chain (R.sub.pf) terminates with a group of formula (I):
CH.sub.2(OCH.sub.2CH.sub.2).sub.tOH (I) wherein t is 0 or from 1 to 5.

5. The upper according to claim 3, wherein both chain ends of said chain (R.sub.pf) terminate with a group of formula (I):
CH.sub.2(OCH.sub.2CH.sub.2).sub.tOH (I) wherein t is 0 or from 1 to 5.

6. The upper according to claim 3, wherein said chain (R.sub.pf) is a chain of formula
O-D-(CFX.sup.#).sub.z1O(R.sub.f)(CFX*).sub.z2-D*-O wherein z1 and z2, equal or different from each other, are equal to or greater than 1; X.sup.# and X*, equal or different from each other, are F or CF3, provided that when z1 and/or z2 are greater than 1, X.sup.# and X* are F; D and D*, equal or different from each other, are an alkylene chain comprising from 1 to 6 carbon atoms, said alkyl chain being optionally substituted with at least one perfluoroalkyl group comprising from 1 to 3 carbon atoms; (R.sub.f) comprises repeating units R.sup.o, said repeating units being independently selected from the group consisting of: (i) CFXO, wherein X is F or CF.sub.3; (ii) CFXCFXO, wherein X, equal or different at each occurrence, is F or CF.sub.3, with the proviso that at least one of X is F; (iii) CF.sub.2CF.sub.2CW.sub.2O, wherein each of W, equal or different from each other, are F, Cl, or H; (iv) CF.sub.2CF.sub.2CF.sub.2CF.sub.2O; and (v) (CF.sub.2).sub.jCFZO wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.(f-a)-T, wherein R.sub.(f-a) is a fluoropolyoxyalkene chain comprising a number of repeating units from 0 to 10, said recurring units being chosen from: CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of each of X being independently F or CF.sub.3 and T being a C.sub.1-C.sub.3 perfluoroalkyl group.

7. The upper according to claim 6, wherein said chain (R.sub.f) is selected from the following formulae (R.sub.f-a) to (R.sub.f-c):
(CF.sub.2O).sub.n(CF.sub.2CF.sub.2O).sub.m(CF.sub.2CF.sub.2CF.sub.2O).sub.p(CF.sub.2CF.sub.2CF.sub.2CF.sub.2O).sub.q(R.sub.f-a) wherein m, n, p, q are 0 or integers selected in such a way as chain R.sub.f meets the above number average molecular weight requirement, with the proviso that if p and q are simultaneously 0, n is not 0;
(CF.sub.2CF(CF.sub.3)O).sub.a(CF.sub.2CF.sub.2O).sub.b(CF.sub.2O).sub.c(CF(CF.sub.3)O).sub.d(R.sub.f-b) wherein a, b, c, d are 0 or integers selected in such a way as chain R.sub.f meets the above number average molecular weight requirement; with the proviso that, at least one of a, c and d is not 0;
(CF.sub.2CF(CF.sub.3)O).sub.e(CF.sub.2O).sub.f(CF(CF.sub.3)O).sub.g(R.sub.f-c) wherein e, f, g are 0 or integers selected in such a way as chain R.sub.f meets the above number average molecular weight requirement.

8. The upper according to claim 1, wherein said hydroxy-terminated (per)fluoropolyether polymer complies with the following formula (PFPE-I):
HO(CH.sub.2CH.sub.2O).sub.tCH.sub.2(R.sub.pf)CH.sub.2(OCH.sub.2CH.sub.2).sub.uOH (PFPE-I) wherein t and u are, each independently, 0 or from 1 to 5; and R.sub.pf is a chain of formula
O-D-(CFX.sup.#).sub.z1O(R.sub.f)(CFX*).sub.z2-D*-O wherein z1 and z2, equal or different from each other, are equal to or greater than 1, X.sup.# and X*, equal or different from each other, are F or CF3, provided that when z1 and/or z2 are greater than 1, X.sup.# and X* are F; D and D*, equal or different from each other, are an alkylene chain comprising from 1 to 6 carbon atoms, said alkyl chain being optionally substituted with at least one perfluoroalkyl group comprising from 1 to 3 carbon atoms; (R.sub.f) comprises repeating units R.sup.o, said repeating units being independently selected from the group consisting of: (i) CFXO, wherein X is F or CF.sub.3; (ii) CFXCFXO, wherein X, equal or different at each occurrence, is F or CF.sub.3, with the proviso that at least one of X is F; (iii) CF.sub.2CF.sub.2CW.sub.2O, wherein each of W, equal or different from each other, are F, Cl, or H; (iv) CF.sub.2CF.sub.2CF.sub.2CF.sub.2O; and (v) (CF.sub.2).sub.jCFZO wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.(f-a)-T, wherein R.sub.(f-a) is a fluoropolyoxyalkene chain comprising a number of repeating units from 0 to 10, said recurring units being chosen from: CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of each of X being independently F or CF.sub.3 and T being a C.sub.1-C.sub.3 perfluoroalkyl group.

9. The upper according to claim 1, wherein said at least one monomer (c) is selected from the group consisting of 4,4-methylene-diphenylene-di-isocyanate (MDI), 1,6-hexan-diisocyanate (HDI), 2,4-toluene-diisocyanate, 2,6-toluene-diisocyanate, xylilen-diisocyanate, naphthalene-diisocyanate, paraphenylen-diisocyanate, hexamethylen-diisocyanate, isophorone-diisocyanate, 4,4-dicyclohexyl-methane-diisocyanate and cyclohexyl-1,4-diisocyanate.

10. The upper according to claim 1, wherein said at least one monomer (d) is selected from the group consisting of ethylene-glycol, 1,4-butanediol (BDO), 1,6-hexane diol (HDO), N,N-diethanolamine and N,N-diisopropanolaniline.

11. The upper according to claim 1, wherein at least 80% of blocks comprising recurring units derived from said monomer (b) are linked, on at least one of their ends, to a block comprising recurring units derived from said monomer (a) through a block comprising recurring units derived from said monomer (c).

12. The upper according to claim 1, wherein said composition (C) is free of plasticizer agents.

13. The upper according to claim 1, wherein said composition (C) comprises said F-TPU polymer in an amount of at least 60 wt. % based on the total weight of said composition (C).

14. The upper according to claim 1, wherein said panel comprises layer E as outermost layer.

15. A footwear article comprising an upper according to claim 1.

16. The upper according to claim 6, wherein D and D*, equal or different from each other, are an alkylene chain comprising from 1 to 3 carbon atoms, said alkyl chain being optionally substituted with at least one perfluoroalkyl group comprising from 1 to 3 carbon atoms.

17. The upper according to claim 6, wherein (R.sub.f) consists of repeating units R.sup.o.

18. The upper according to claim 7, wherein: when m is other than 0, the m/n ratio is between 0.1 and 20; when (m+n) is other than 0, (p+q)/(m+n) is between 0 and 0.2; when b is other than 0, a/b is between 0.1 and 10; when (a+b) is different from 0, (c+d)/(a+b) is between 0.01 and 0.5; or when e is other than 0, (f+g)/e is between 0.01 and 0.5.

Description

DESCRIPTION OF EMBODIMENTS

[0017] For the purposes of the present description and of the following claims: [0018] the term (per)fluoropolyether is intended to indicate a fully or partially fluorinated polyether; [0019] the expression (per)fluoropolyoxyalkylene chain is intended to indicate a partially or fully fluorinated, straight or branched, polyoxyalkylene chain; [0020] the use of parentheses before and after symbols or numbers identifying compounds, chemical formulae or parts of formulae has the mere purpose of better distinguishing those symbols or numbers from the rest of the text and hence said parentheses can also be omitted; [0021] the term upper (also referred to as vamp) is intended to indicate the part of a footwear article (such as shoes, boot and the like) that covers the toes, the top of the foot, the sides of the foot, and the back of the heel, and is attached to the outsole of the footwear article; [0022] the term panel is intended to indicate the part(s) that form(s) the upper.

[0023] The upper can be manufactured using only one panel or joining together more than one panels. When more two or more panels are joined together to form the upper, the panels can be selected from for example the toe box, the toe cap, the quarter, the vamp, the tongue, the counter and the back strap of a footwear.

[0024] Preferably, said F-TPU polymer is a block copolymer, i.e. a polymer comprising blocks (also referred to as segments), each block comprising recurring units deriving from at least one monomer (a), at least one monomer (b), at least one monomer (c) and at least one monomer (d), as defined above.

[0025] Preferably, said F-TPU polymer has an average number molecular weight of from 30,000 to about 70,000 Da.

[0026] Preferably, said F-TPU polymer has a melting point (T.sub.m) of from about 120 C. to about 240 C.

[0027] Preferably, said at least one monomer (a) has an average number molecular weight of from 500 to 4,000 Da, more preferably of from 1,000 to 4,000.

[0028] Preferably, said at least one monomer (a) is selected in the group comprising, more preferably consisting of, poly(ethylene)glycol, poly(propylene)glycol, poly(tetramethylen)glycol (PTMG), poly(1,4-butanediol)adipate, poly(ethandiol-1,4-butanedio) adipate, poly(1,6-hexandiol-neopentyl)glycol adipate, poly-caprolactone-diol (PCL) and polycarbonate-diol.

[0029] Poly(tetramethylen)glycol, poly-caprolactone-diol and polycarbonate-diol being particularly preferred.

[0030] Preferably, said at least one monomer (b) is a hydroxy-terminated (per)fluoropolyether polymer [PFPE polymer], i.e. a polymer comprising a (per)fluoropolyoxyalkylene chain [chain (R.sub.pf)] having two chain ends, wherein one or both chain ends terminates with at least one OH group.

[0031] Preferably, at least one chain end of said chain (R.sub.pf) terminates with a group of formula:

CH.sub.2(OCH.sub.2CH.sub.2).sub.tOH (I)

[0032] wherein

[0033] t is 0 or from 1 to 5.

[0034] More preferably, both chain ends of said chain (R.sub.pf) terminate with a group of formula (I) as defined above.

[0035] Preferably, said chain (R.sub.pf) is a chain of formula

O-D-(CFX.sup.#).sub.z1O(R.sub.f)(CFX*).sub.z2-D*-O

[0036] wherein

[0037] z1 and z2, equal or different from each other, are equal to or higher than 1;

[0038] X.sup.# and X*, equal or different from each other, are F or CF3, provided that when z1 and/or z2 are higher than 1, X.sup.# and X* are F;

[0039] D and D*, equal or different from each other, are an alkylene chain comprising from 1 to 6 and even more preferably from 1 to 3 carbon atoms, said alkyl chain being optionally substituted with at least one perfluoroalkyl group comprising from 1 to 3 carbon atoms;

[0040] (R.sub.f) comprises, preferably consists of, repeating units R , said repeating units being independently selected from the group consisting of:

[0041] (i) CFXO, wherein X is F or CF.sub.3;

[0042] (ii) CFXCFXO, wherein X, equal or different at each occurrence, is F or CF.sub.3, with the proviso that at least one of X is F;

[0043] (iii) CF.sub.2CF.sub.2CW.sub.2O, wherein each of W, equal or different from each other, are F, Cl, H;

[0044] (iv) CF.sub.2CF.sub.2CF.sub.2CF.sub.2O;

[0045] (v) (CF.sub.2).sub.jCFZO wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.(f-a)-T, wherein R.sub.(f-a) is a fluoropolyoxyalkene chain comprising a number of repeating units from 0 to 10, said recurring units being chosen among the following: CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of each of X being independently F or CF.sub.3 and T being a C.sub.1-C.sub.3 perfluoroalkyl group.

[0046] More preferably, chain (R.sub.f) is selected from the following formulae (R.sub.f-a) to (R.sub.f-c):

(CF.sub.2O).sub.n(CF.sub.2CF.sub.2O).sub.m(CF.sub.2CF.sub.2CF.sub.2O).sub.p(CF.sub.2CF.sub.2CF.sub.2CF.sub.2O).sub.q(R.sub.f-a)

[0047] wherein m, n, p, q are 0 or integers selected in such a way as chain R.sub.f meets the above number average molecular weight requirement, with the proviso that if, p and q are simultaneously 0, n is not 0; when m is other than 0, the m/n ratio is preferably between 0.1 and 20; when (m+n) is other than 0, (p+q)/(m+n) is preferably between 0 and 0.2;

(CF.sub.2CF(CF.sub.3)O).sub.a(CF.sub.2CF.sub.2O).sub.b(CF.sub.2O).sub.c(CF(CF.sub.3)O).sub.d(R.sub.f-b)

[0048] wherein a, b, c, d are 0 or integers selected in such a way as chain R.sub.f meets the above number average molecular weight requirement; with the proviso that, at least one of a, c and d is not 0; when b is other than 0, a/b is preferably between 0.1 and 10; when (a+b) is different from 0 (c+d)/(a+b) preferably is between 0.01 and 0.5, more preferably between 0.01 and 0.2;

(CF.sub.2CF(CF.sub.3)O).sub.e(CF.sub.2O).sub.f(CF(CF.sub.3)O).sub.g(R.sub.f-c)

[0049] wherein e, f, g are 0 or integers selected in such a way as chain R.sub.f meets the above number average molecular weight requirement; when e is other than 0, (f+g)/e is preferably between 0.01 and 0.5, more preferably between 0.01 and 0.2.

[0050] PFPE polymers wherein chain (R.sub.f) complies with formula (R.sub.f-a) as defined above, wherein p and q are 0, are particularly preferred in the present invention.

[0051] In a preferred embodiment, said PFPE polymer complies with the following formula (PFPE-I):

HO(CH.sub.2CH.sub.2O).sub.tCH.sub.2(R.sub.pf)CH.sub.2(OCH.sub.2CH.sub.2).sub.uOH (PFPE-I)

[0052] wherein

[0053] t and u are, each independently, 0 or from 1 to 5; and

[0054] R.sub.pf is as defined above.

[0055] Preferably, said PFPE polymer has an average number molecular weight of from 400 to 10,000 Da, more preferably from 1,000 to 5,000.

[0056] In a preferred embodiment, the molar ratio between monomers (a) and monomers (b) is from 2 to 20, more preferably from 2 to 10.

[0057] In a preferred embodiment, the amount of monomers (b) is such that the F-TPU polymer comprises from 4 to 30 wt.% of fluorine.

[0058] Preferably, said at least one monomer (c) has a number molecular weight of 500 Da or lower, preferably from 10 to 500 Da.

[0059] Preferably, said at least one monomer (c) is selected in the group comprising, preferably consisting of, 4,4-methylene-diphenylene-di-isocyanate (MDI), 1,6-hexan-diisocyanate (HDI), 2,4-toluene-diisocyanate, 2,6-toluene-diisocyanate, xylilen-diisocyanate, naphthalene-diisocyanate, paraphenylen-diisocyanate, hexamaethylen-diisocyanate, isophorone-diisocyanate, 4,4-dicyclohexyl-methane-diisocyanate and cyclohexyl-1,4-diisocyanate.

[0060] MDI and HDI being particularly preferred.

[0061] Preferably, said at least one monomer (d) is selected in the group comprising, preferably consisting of, ethylene-glycol, 1,4-butanediol (BDO), 1,6-hexane diol (HDO), N,N-diethanolamine and N,N-diisopropanolaniline.

[0062] BDO and HDO being particularly preferred.

[0063] In a preferred embodiment, the sum of blocks deriving from monomers (c) and (d) is from 10 to 60 wt. % based on the total weight of the F-TPU polymer.

[0064] Those skilled in the art would readily understand that blocks comprising recurring units derived from monomers (a) and (b) are rubber-like blocks, while blocks comprising recurring units derived from monomers (c) and (d) are hard blocks.

[0065] In a preferred embodiment, at least 80% of the blocks comprising recurring units derived from said monomers (b) [blocks B] are linked, at least one of their ends, to a block comprising recurring units derived from monomers (a) [blocks A] through a block comprising recurring units derived from monomers (c) [blocks C].

[0066] In other words, at least 80% of blocks B are contained in a sequence of the following type: -[A-C-B-C]-.

[0067] Advantageously, the F-TPU polymer can be prepared following the procedures disclosed in U.S. Pat. No. 5,332,798 (AUSIMONT S.P.A.), in particular in Example 15.

[0068] According to a preferred embodiment, the upper is made from a composition (C) that is free of plasticizer agents.

[0069] Preferably, said composition (C) comprises the F-TPU polymer as defined above as the main component.

[0070] More preferably, said F-TPU polymer is in an amount of at least 60 wt. %, more preferably at least 80 wt. %, even more preferably at least 85 wt. % based on the total weight of said composition (C).

[0071] In addition to the F-TPU polymer, said composition (C) can optionally comprise further additives, such as for example antioxidants, thermal stabilizers, dyestuffs and fillers.

[0072] Embodiments wherein said composition (C) is essentially made of said F-TPU polymer in combination with an amount of up to 1 wt. % of any of the additives listed above are also encompassed by the present invention.

[0073] According to a first embodiment, said upper comprises a plurality of panels stitched together, each panel comprising a layer E as defined above.

[0074] According to an alternative embodiment, said upper comprises one single panel, which extends for the entire surface of the upper and comprises a layer E as defined above. Uppers comprising one single panel are also known as unitary upper design.

[0075] Layer E can be manufactured following methods known in the art, for example by melt-blown process as disclosed in US 2010/0186874 cited above

[0076] As an example, layer E can be manufactured by a process comprising the following steps:

[0077] (i) providing a mould;

[0078] (ii) filling said mould with a composition comprising at least one elastomeric fluorinated polyurethane [F-TPU polymer] as defined above;

[0079] (iii) sealing the mould;

[0080] (iv) heat treating the sealed mould; and

[0081] (v) extracting the article from the mould.

[0082] Preferably, step (iv) comprises two steps, wherein the first step comprises heating at a first temperature for a time from 10 seconds to 10 minutes and the second step comprises heating at a second temperature, said second temperature being lower than said first temperature, for a time of from 30 seconds to 24 hours.

[0083] More preferably, said first temperature is from 120 C. to 300 C.

[0084] More preferably, said second temperature is from 50 C. to 200 C.

[0085] Alternatively, step (iv) comprises only one step of heating at a temperature of from 50 C. to 300 C. for a time of from 10 seconds to 24 hours.

[0086] Preferably, after step (iv) and before step (v), the mould is allowed to cool down.

[0087] According to a preferred embodiment, said at least one panel comprises layer E as the only layer.

[0088] According to another preferred embodiment, said at least one panel comprises layer E as defined above and at least one texture layer [layer T] consisting of texture yarns.

[0089] For example, according to an embodiment, the upper according to the present invention comprises at least one panel comprising layer E as defined above, said layer E having an external surface and an internal surface, wherein at least a part of said internal surface is connected with a texture layer [layer T] consisting of texture yarns.

[0090] According to another embodiment, the upper according to the present invention comprises at least one panel comprising layer E as defined above and two layers T consisting of texture yarns, wherein layer E is interposed between two layers T.

[0091] When the upper comprises layer E and layer(s) T, the upper is obtained by welding together layer E and layer(s) T.

[0092] The welding can be performed for example using a high-frequency welding process or an ultrasonic sound welding process.

[0093] In a further embodiment, the present invention relates to a footwear article comprising an upper as defined above.

[0094] Should the disclosure of any patents, patent applications, and publications which are incorporated herein by reference conflict with the description of the present application to the extent that it may render a term unclear, the present description shall take precedence.

[0095] The invention will be herein after illustrated in greater detail by means of the Examples contained in the following Experimental Section; the Examples are merely illustrative and are by no means to be interpreted as limiting the scope of the invention.

EXPERIMENTAL PART

[0096] Materials [0097] Monomers (a):

[0098] (a1) CAPA 2201 (from Perstorp) polycaprolactone-diol (PLC) having molecular weight (Mw) of about 2,000 and OH value of about 56 mg KOH/g;

[0099] (a2) polytetramethyleneglycol (PTMEG) having Mw of about 2,000

[0100] (a3) ETERNACOLL UH200 (from UBE) polycarbonate-diol (PCD) having Mw of about 2,000

[0101] (a4) BESTER (from DOW) polyester-diol having Mw of about 2,000 [0102] Monomers (b) having formula:

H(OCH.sub.2CH.sub.2).sub.pOCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.m(CF.sub.2O).sub.nCF.sub.2CH.sub.2O(CH.sub.2CH.sub.2O).sub.pH

[0103] (b1) p=4.7 and Mw of about 2,000

[0104] (b2) p=1.6 and Mw of about 1,700 [0105] Monomers (c):

[0106] (c1) diphenylen-4,4-diisocyanate (MDI)

[0107] (c2) 1,6-hexan-diisocyanate (HDI) [0108] Monomers (d):

[0109] (d1) 1,4-butanediol (BDO)

[0110] (d2) 1,6-hexandiol (HDO) [0111] Catalyst:

[0112] bismuth neodecanoate

[0113] Preparation of F-TPU Polymer SpecimensMethod A

[0114] F-TPU polymer specimens 1 to 4 in the form of sheet were prepared starting from the abovementioned monomers following the same procedure detailed in Example 15 of U.S. Pat. No. 5,332,798 (to Ausimont S.p.A.) cited above.

[0115] F-TPU polymers thus obtained contained 20 wt. % of recurring units derived from monomers (b).

[0116] Preparation of F-TPU Polymer SpecimensMethod B

[0117] F-TPU polymer specimens 5 to 7 and 8 (the latter as comparison) in the form of sheet were prepared as follows: [0118] the hydrogenated pre-polymer was synthetized by reacting monomer (c) and monomer (a) in the equivalent ratio 2 to 1, at a temperature of 90 C.; [0119] the fluorinated pre-polymer was synthetized by reacting monomer (c) and monomer (b) in the equivalent ratio 2 to 1, at a temperature of 90 C.; [0120] the hydrogenated pre-polymer and the fluorinated pre-polymer were then mixed together and stirred at 90 C. for 30 minutes; [0121] monomer (c) was further added depending on the selected stoichiometry; [0122] the reaction was continued at 90 C. for 3 minutes until chain-extension was completed; [0123] the polymer thus obtained was casted at 100 C. for 24 hours.

[0124] The compositions of the F-TPU polymers obtained following methods A and B described above and the compositions of comparative hydrogenated polyurethane polymers (H-TPU) are reported in the following Table 1.

[0125] As further comparison, a commercially available hydrogenated TPU (H-TPU 9*) was used. The monomers ratio for H-TPU 9* is not publicly available.

TABLE-US-00001 TABLE 1 Monomers (ratio by mol) a1 a2 a3 a4 b1 b2 c1 c2 d1 d2 F-TPU 1 0.8 0.2 2.0 1.0 F-TPU 2 0.7 0.3 3.0 2.0 F-TPU 3 0.6 0.4 2.5 1.5 F-TPU 4 0.75 0.25 2.0 1.0 F-TPU 5 0.75 0.25 3.0 2.0 F-TPU 6 0.75 0.25 2.0 1.0 F-TPU 7 4.0 0.3 0.7 3.0 H-TPU 1.0 2.0 1.0 8(*) H-TPU n/a n/a n/a 9(*) (*)comparison n/a = value not available

[0126] The mechanical properties of sheets made from F-TPU and H-TPU polymers were evaluated and the results are reported in Table 2.

TABLE-US-00002 TABLE 2 Shore Tensile Elongation at A strength (MPa) break (%) F-TPU 1 85 28.1 471 F-TPU 2 93 31 410 F-TPU 3 80 35 400 F-TPU 4 75 7.30 590 F-TPU 5 90 26.1 505 F-TPU 6 83 13 550 F-TPU 7 91 31.8 506 H-TPU 8(*) 78 40 550 (*)comparison

[0127] The above results show that the F-TPU polymers according to the present invention have mechanical properties comparable with the mechanical properties of H-TPU polymers typically used in the production of the upper of footwear articles, and hence F-TPU polymers provide good mechanical properties to the finished upper.

[0128] The sheets were used in the Examples described hereinafter.

Example 1

Contact Angle

[0129] This test is considered to be predictive for both stain and chemical resistance.

[0130] The static contact angle (SCA) of a sessile drop (about 5 L) of water and n-hexadecane as solvents was measured with the DSA30 instrument (Krss GmbH, Germany). The SCA values as well as standard deviations were calculated among ten contact angles.

[0131] Surface free energy (SFE) was calculated following the Owens, Wendt, Rabel and Kaelble method (WORK method), which is a standard method for calculating the surface free energy of a solid from the contact angle with several liquids.

[0132] The results are summarized in the following Table 3.

TABLE-US-00003 TABLE 3 SCA SCA SFE Sample H.sub.2O C.sub.16 (mN/m) F-TPU 1 104 64.5 16.1 F-TPU 2 110.5 63.6 15.09 F-TPU 3 106.7 62.9 15.90 F-TPU 4 86 61 23.6 F-TPU 5 105 68 14.9 F-TPU 6 103 66 16 F-TPU 7 98 70 16.9 H-TPU 8(*) 77 46 30.93 H-TPU 9(*) 81 29 31.7 (*)comparison SCA = Static Contact Angle H2O = water C-16 = hexadecane SFE = Surface Free Energy

[0133] The above results show that the contact angle measured with both water (H.sub.2O) and hexadecane (C.sub.16) increased while the surface energy dropped down to the range from 15 to 16 mN/m compared to 31 mN/m for the hydrogenated thermoplastic polyurethane used as reference compound. These data are consistent with an increase in terms of stain resistance and chemical resistance conferred by the F-TPU polymers compared to H-TPU polymers.

Example 2

Blue Denim Test

[0134] This test is considered to be predictive for both staining and abrasion resistance.

[0135] The test was performed with the instrument Taber Industries 5750 Linear Abraser, that was set to run at the following conditions: [0136] cycle speed: 30 cycles/min [0137] stroke length: 2.54 cm (1 inch) [0138] number of cycles: 200 [0139] total load: 1 kg.

[0140] Tests were performed once with dry denim and once with wet denim on F-TPU 1, F-TPU 2, F-TPU 3, F-TPU 5 and F-TPU 7.

[0141] Before performing the test with wet denim, denim was submerged in water for 10 second, then it was removed and water was squeezed out by hand so that denim did not drip but was wet to the touch.

[0142] The tests were performed as follows: a denim sample measuring approximately 30 mm30 mm was fixed to a fixture in order to prevent shifting of the sample during the test. A sample of each F-TPU and of H-TPU was then placed on the denim sample and fixed to the fixture as well.

[0143] Checkpoints were set as follows: [0144] after rub and [0145] after cleaning with isopropyl-alcohol (IPA).

[0146] Results for the dry test: no stain was observed for F-TPU 1, F-TPU 2, F-TPU 3, F-TPU 5 and F-TPU 7.

[0147] Results for the wet test: a very light halo was observed for F-TPU 1, F-TPU 2, F-TPU 3, F-TPU 5 and F-TPU 7.

Example 3

Stain Test

[0148] A drop of each staining agent listed above was put into contact with the surface of a specimen made from F-TPU 1 and let for 24 hours at ambient conditions. The specimen was then cleaned with water.

[0149] A specimen made from H-TPU was used as comparison and treated as disclosed above.

[0150] The results are summarized in the following Table 4, wherein: [0151] ++=no stain [0152] +=mark/halo [0153] =stain

TABLE-US-00004 TABLE 4 Staining agent H-TPU(*) F-TPU 1 Olive oil ++ Ketchup + ++ Hot Coffee + Mayonaise ++ Coca Cola ++ Mustard + Vinager ++ ++ Windex cleaner + + Formula 409 cleaner + + Purell hand sanitizer + ++ Vaseline intensive care lotion ++ Alcohol ++ (*)comparison

[0154] The above results clearly showed the increase in term of both stain and chemical resistance of the F-TPU specimen compared to the H-TPU specimen.

Example 4

Evaluation of Haptic Properties

[0155] The haptic properties (notably the feeling of softness) of F-TPUs and the H-TPUs were measured by testing the sheets of the materials subjectively by hand feel of 5 individuals.

[0156] Soft feel was measured subjectively by hand touch and rated on a scale from 1 to 5, with 1 being poor soft feel (hard feel) and 5 being excellent soft feel. Participants took part in this study individually, so they did not influence each other in their responses. Participants were presented with the four samples in a random order and asked to feel and rate them.

[0157] The results are summarized in the following Table 5.

TABLE-US-00005 TABLE 5 Rating Indivi- Indivi- Indivi- Indivi- Indivi- Sample dual 1 dual 2 dual 3 dual 4 dual 5 Average F-TPU 1 4 5 4 4 5 4.4 F-TPU 2 5 5 5 4 5 4.8 F-TPU 3 5 4 4 4 4 4.2 F-TPU 4 5 5 5 4 5 4.8 F-TPU 5 5 4 4 3 4 4.0 F-TPU 6 5 4 5 4 4 4.4 F-TPU 7 4 4 4 4 5 4.2 H-TPU 2 1 1 1 2 1.4 8(*) H-TPU 2 2 1 1 2 1.6 9(*) (*)comparison

[0158] The above results clearly showed that the sheets obtained with the F-TPUs according to the present invention showed better haptic properties, notably improved feeling of softness, when compared to sheets obtained from H-TPU polymers.