GB2175489A - Production of footwear - Google Patents

Abstract

Process for the production of footwear with polyurethane coated uppers and thermally bonded sole, wherein the shoe upper material is coated, before making the pattern, with a hydroxy-terminated polyurethane that contains either and/or ester groupings and has a glass-transition temperature below 200 DEG C and, after fitting and lasting of the upper, this is bonded directly (i.e. without roughing or scouring the margins of the uppers and without the use of other cementing agents or adhesive on the margins) to the sole by heat treatment at temperatures of at least 50 DEG C, and footwear so produced; if desired the polyurethane may be mixed with vinyl chloride copolymers as described herein.

Description

SPECIFICATION Production of footwear Forthe soling ofshoe uppers by bonding ofthe sole itis generally necessary to rough the margins ofthe shoe uppers (eitherto be lasted or already lasted) to which the outer sole is then bonded. It has now been found that by means of a particularfinal coating ofthe material for the shoe uppers before making the pattern ofthe upper, the shoe uppers may be directly bonded to the sole by the heat treatment without roughing or scouring the margins ofthe uppers and withoutthe use of any other adhesive or cementing agent on said margins.

Th us the invention provides a processforthe production of footwear with polyurethane-coated uppers and thermally bonded sole, wherein the shoe upper material is coated, before making the pattern, with a hydroxy-terminated polyurethane that contains ether and/or ester groupings and has a glass-transition temperature below 200"C and, afterfifting and lasting, the upper is bonded directly to the sole by heat treatment at temperatures of at least 50"C.

The polyurethanesto be used according tothe invention may be unitary polyurethanes or mixtures of polyurethanes and are in general obtainable by methods known perse by reaction of polyisocyanates with polyols and optionally chain extending components. Preferably the hydroxy-terminated polyurethanes are polyaddition products of (a) polyisocyanates (b) long-chain polyester- and/or-etherpolyols and optionally (c) low molecular polyfunctional isocyanate-reactive components.

The polyisocyanates (a) are preferably diisocyanates. Preferred diisocyanates are polymethylene diisocyanates with 2-6 methylene groupings, isophorone diisocyanate, toluene diisocyanate, xylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate, of which the aromatic diisocyanates, especially diphenylmethane diisocyanate, are particularly preferred.

The polyols (b) are preferably linear polymeric diols, particularly polyesterdiols and polyetherdiols having terminal hydroxy groups, and with an average molecular weight of 300-4000, preferably 1000-3500.

Preferred polyesterdiols are reaction products of C26 aikanediols, preferably ethylene glycol, 1,3-propane diol,1,4-butanediol, neopentyl glycol,1,6-hexanediol or diethylene glycol with aliphatic or aromatic dicarboxylicacids. Preferred diacids contain 4-8 carbon atoms and include maleic, succinic, sebacic, adipic and phthalic acid of which adipic acid is preferred.

Alternatively, the diols may be reacted with a lactone, e.g. caprolactone, to give a hydroxy-terminated polycaprolactone. Preferred polyetherdiols are polymeric glycols, e.g. polypropylene glycol, or reaction products of the above dials with tetrahydrofuran to hyd roxy-terminated polytetrahydrofu rans. The polyesterdiols are particularly preferred.

The components (c) contain advantageously 2to 9 carbon atomsand are preferably aliphatic diamines e.g. propylene diamine and isophorone diamine; or more preferablyalkane diols as indicated above, diethylene glycol ortriethylene glycol. Most preferably the component (c) is an alkane diol with 2-6 carbon atoms.

The polyurethanes to be used according to the invention are hydroxyterminated and thus the weight ratios ofthe components (a), (b) and (c) are to be chosen so that per equivalent of polyisocyanate there is employed morethan one equivalent ofthetotal of the isocyanate-reactive components (b) and, if present, (c). Advantageously there are employed per equivalent of polyol (b) 0.8 to 0.9995, preferably 0.85 to 0.9991 equivalents of polyisocyanate (a). If a component (c) is also present, correspondingly more polyisocyanate may be used, preferably so that component (c) together with the additional polyisocyanate acts as a chain extender.Per equivalent ofthe component (b) there are employed preferably x equivalents of component (c) and (y + x) equivalents of component (a) wherein y is a numberfrom 0.8 to 0.9995, more preferably from 0.85 to 0.9991, and xis greaterthan or equal toO. With particular preference the polyurethanes are at least in part such in which xis Oto 1 more preferably 0.2 to 1 in particular 0.2 to 0.8; the remaining being such in which xis preferably > 1 and more preferably < 2, in particular < 1,8, especially up to 1,77. By one equivalent there is meantthe quantity corresponding to the molarweight divided bythefunctionality ofthe compound.When components ofthe same functionality are used-the preferred components are all difunctional-the equivalent ratio corresponds of course to the molar ratio.

The polyurethanes are obtainable in a manner known perse andthusthe components (a), (b) and (c) may be reacted with each other under conventional conditions, mainly attemperatures from 40"Cto the boiling temperature, preferably from 50 to 75"C, advantageously in an inert organic solventthat is volatile under application conditions (e.g. in the temperature range of 50 to 110 C). Suitable solvents include dialkyl ketones (preferably methyl ethyl ketone), cyclohexanone and aliphatic carboxylic acid esters (preferably ethyl acetate or ethoxyethyl acetate), which may be blended with aromatic solvents, preferablytoluene orxylene, the reaction being carried out preferably in the presence of a suitable catalyst preferably a tin compound such as Sn-ll- octoateordibutyltin dilaurate.

If desired, the polyurethanes to be used according to the invention may be blended with vinyl chloride copolymers, in particular copolymers of vinyl chloride and vinyl acetate, wherein 10-50 weight % ofthe copolymerconsist of vinyl acetate monomer, and which mayfurther contain a copolymerised unsatu rated dicarboxylic acid, preferably maleic acid, the weight ratio ofthe unsaturated dicarboxylic acid in the copolymer being upto 10weight % ofthe copolymer.

Preferably these copolymers are soluble in organic solvents (e.g. as defined above) and have an average molecularweight of 500 to 20,000, more preferably 1000 to 8000. The weight ratio ofthe vinyl chloride copolymertothe polyurethane is preferably upto 20 weight %, more preferably 0.5-20 weight %, in particular 2-20 weight %. The proportion of the above defined hydroxyterminated polyurethanes in which x is 0-1, in the total ofthe polymers in the coating e'the invention, is advantageously at least 10 weight %, preferably at least 17weight %, in particularupto 74 weight %. The proportion ofthe hydroxy-terminated polyurethanesinwhichx > 1 inthetotal ofthe polymers in the coating of the invention is preferably at least 22 weight %, in particular up to 80 weight %.

The polyurethanes optionallytogetherwith the vinyl chloride copolymers, a re are advantageouslyformu- lated as liquid compositions in the above mentioned solvents and may contain e.g. only the solvent used in their synthesis or may also be diluted with the same or different inert solvents that are volatile underapplica- tion conditions, preferably with ethyl acetate, cyclohexanone, xylene, toluene or dimethyl formamide.

For concentrated compositions the concentration is preferably 15-40 weight %, more preferably 25-40 weight % calculated as solid residue in the composition. The viscosities ofthese concentrated compositions may range in a broad scope, e.g.from 5000 50000 mPas at 20"C. For application on the substrates these compositions may, if required, be further diluted with suitable solvents, preferablythe ones indicated above, to the viscosity suitable forthe chosen application method. These compositions are in gener alclearandare normallytrueorcolloidalsolutions.

If desired the above mentioned polyurethane compositions may be treated with conventional additives such as antioxidants, UV-absorbers,fungicides, opacifying agents and/orsuitable dyestuffs may be inorganic pigments or also organic pigments, in particular metal complexes, e.g. such as described in Beckerand Braun "Kunststoffhandbuch", Volume7 ("Polyurethane"), Karl HanserVerlag, Munchen,Wien, 1983,on page 108.

The above polyurethanes forthe coating ofthe invention are essentially one-component polyurethanes (or mixturesthereof).

The substrate forthe shoe uppers may be in general any conventional substrate as is usuallycoated with polyurethanes and used forthe production offootwear, mainly synthetic materials (in particular polyurethane and polyvinyl chloride) and leather (in particularsplitleatherand buffed leather). Beforethe final coating according to the invention, these substrates are preferably coated with other coatings, in particularwith a base coat (or adhesive coat) and a top coat (preferably a iacquer); a pre-top-coat(an intermediate coat) may be applied on the base coat before application ofthe top coat, in particularwhen the substrate is synthetic.The leather substrates may be more or less fatted and/or hydrophobized and for this purpose the base coat may contain, in addition to the polymers, waxes and/orfatting oils; the content of such waxes and/or oils being preferably up to 30 weight % ofthe synthetic polymer in the base coating composition. A higher content of such fatting agents may affect the bond strength between sole and upper.

Preferably all ofthe above mentioned coatings of the substrates are polyurethane based. Forthe base coattherearepreferablyemployed one-component polyurethane systems in which the polyurethanes are hydroxy-terminated and are made of polyester polyols mainly as indicated above, short chain diols (mainly as indicated above) and aromatic or aliphatic diisocyanates, mainly as described above, and in a molar ratio as indicated above. These polyurethanes are preferably employed in the form oftheirsolutions in inert organic solvents, e.g. as indicated above.For the pre-top-coatthere are employed preferablytwocomponent systems which after application on the substrates are polymerised to the corresponding polyurethanes, the one ofthe components being an isocyanate-terminated polyurethane of aromatic and/ or aliphatic diisocyanates and polyether-and/or-ester polyols, e.g. as described above, and the other component being an aliphatic or aromatic polyamine that by reaction with the isocyanate-terminated polyurethanes leads to a polyurea-urethane coating.

The polyamines may be in general any conventional low molecular weight amines, preferably polymethylene diamine with 2-6 carbon atoms, dieth ylene triamine, triethyiene tetramine, dipropylene triamine, methaphenylene diamine, isophoronedi amine, 4,4'-dicyclohexylmethane-diamine, 4,4'-di- aminodiphenylmethane, 3-3'-dimethyl -4,4' - diaminodicyclohexylmethane ortolylene diamine. These pre-top-coat compositions are preferably applied in the absence of any solvent on the substrate where the reaction takes place.Forthetop-coatthere are employed preferably one-component polyurea urethanes which are preferably hydroxy-terminated and derived from polyester polyols (e.g. as indicated above) polyisocyanates (e.g. as indicated above) and polyamines (e.g. as indicated above), the polyester polyols, the polyisocyanates and the polyamines being preferably aliphatic; these one-component polyurea-urethanes are preferablyapplied in the form of their solutions in organic solvents, analogously as described above. Pre-top-coat and top-coat may, if desired, contain conventional additives, e.g. as indicated above.

The coating compositions may be applied by any conventional method, e.g. by means of a rollercoater, a rubbercylinder,a curtain coater, an airknife, a pressure sieve, an airless sprayer oraspray pistoi, and after each coating procedure the resulting coating is suitably dried, preferably in the temperature range of from 40 two 140"C, more preferably40-90 C.

The hydroxy-terminated polyurethane for the final coating (finish) ofthe invention may be applied by any conventional method, e.g. the ones indicated above or bythe transfer process preferably attemperatures in the range of 50-230"C, more preferably 80-110"C, suitably by means of a textile or non-textile optionally embossed support that is stable atthe application and transfertemperatures. Forthis purpose the polyurethane composition ofthe invention may be applied on the support and, preferably before drying, transferred onthesubstrate, which may have been previously coated with other coating as indicated a bove. Alternatively all of the coatings may be applied in the inverse sequence on the support, and each of the coatings with the exception ofthe last one is dried, and then the whole complex ofthe coatings is transferred on the uncoated substrate. The transfer temperature is preferably lowerthan or equal to 1 1 OOC when at least one orthe coatings contains a solvent The so coated materials may then be cut, fitted and lasted so as to make lasted uppers, which are then thermally directly bonded to the (outer) sole. By direct bondingoftheupperwiththesolethereismeantthe bonding ofthe upperwith the sole without any roughingorscouring of the margins, and without the use of any other adhesive or cementing agent on the margins.Even a swelling ofthe margin is not necessary and not recommended. The ridges on the lasted margins may, however, be skived or cut away if desired. If desired,there may be applied on the margin ofthe upper a thicker layer ofthe hydroxy-terminated polyurethane ofthe invention than is used forthefinal coating ofthe remaining portion ofthe upper. The quantity of application ofthe hydroxy-terminated polyurethanes ofthe invention, optionally in admix turewithvinyl chloride copolymers, forthefinal coating lies preferably in the range of 3-20 g/m2 and for an optionally further coated upper-margin in the range of 3-50, preferably 5-25g/m2, referred to the solid content ofthe coating.The weight ofthe total of the polymers used for all ofthe coatings per m2 lies preferably in the range offrom 100to 600, more preferablufrom 150to 450 9 of solid substance.

The bottoming (i.e. the bonding ofthe sole to the upper) may be carried out by any conventional thermal bonding procedure, preferably by director injection moulding (forthe application of synthetic soles) or by heating ofthealreadyformed soletothe desired temperature e.g. by iR-shock-reactivation and joining ofthesolewith the uppere.g. by means of an AGO-machine.

Forthethermal bonding ofthe upper (namelythe margins ofthe upper) with the sole, the coating is heated in order to reactivate the polyurethane coating ofthe invention. If the polyurethane coating is free of solvents or practically free of solvents, the coating is heated to a temperature preferably of at least 1 OOOC for reactivation.Advantageously the temperature is below the melting point of the polyurethane, preferably in orabovethe melting rangeofthecristallitesofthe polyurethane; more preferably the bonding temperatureforthe solvent-free bonding procedure is in the range of 105-230"C, in particular in the range of 140-220"C. This process is particularly suitable for the application of synthetic soles by the direct moulding orinjection moulding procedure.The moulding temperature for polyurethane foam soles is preferably inthe rangeof 140-210 Candforpolyvinyl chloride soles preferably in the range of 150-220"C. The heat stored by the molten or foamed mass is sufficient for the reactivation ofthe polyurethane coating and for achieving a sole/upper bond of excellent bending strength and tensile strength.Ifthe polyurethane coating or at least one of the polyurethane coatings contains a solvent (e.g. as described aboveforthe compositions) the temperature for reactivation may be correspondingly lowered, namely down to values of at least 50"C; in this case the temperature is advantageously in the range of 50 to 11 00C, preferably 60 to 100 C, more preferably 60 to 90 C. Forthe application of preformed soles that might be damaged or deformed in the temperature range for the solventfree bonding it is preferred to operate with an additional polyurethane coating, which is solventcontaining, preferably by applying on the margin of the upper a layer of a solvent-containing polyurethane composition ofthe invention as defined above and/or by coating the sole with such a polyurethane composition preferably in a quantity of application of 20-50 g of solid substance per and bonding the upperwith the sole before the complete evaporation ofthe solvent attemperatu resin the range of 50-11 0'C preferably 60-90"C; for this purpose it is advantageous to heat the sole to the desired reactivation temperature and join it immediately with the upper; the heat stored by the sole is sufficientforthe reactivation of the polyurethane and for achieving a firm bond of excellent bending and tensile strength between sole and upper.

After cooling, the raw footwear is ready and may be completed in the usual way if and as required, e.g. by the application of heels, if required, and finishing in the usual way (finishing ofthe sole, scouring, trim- ming, polishing, cleaning etc.).

The polyurethane finish films ofthe invention meet the conventional high requirements for polyurethane finishes, and are in particular of notable resistance to hydrolysis, notable soil repellency, impermeability to waterand permeabilitytovapourandarecharacte- rised by a very high flexibility and elasticity ofthefilm; they are also suitable forthe production of temperature-resistantfootwear.

An embossing ofthe upper material or ofthe coated upper material is not affected bythefinish film ofthe invention.

In thefollowing examplestheterm "polyol" is used to indicate the specific polymeric diols (polyester diols). The used polylactones are commercial products available underthe trade names "TONE 0221 " (MW 1000) and "TONE 0260" (MW 3000) of Union Carbide, USA.

Example 1 In a reaction vessel fitted with a blade stirrer are placed 1000 g of methyl ethyl ketone. To this solvent are added 1000 g of polyesterdiol which is a polycondensation product of ethyleneglycol and adipic acid with a molecular weight of 2000. The mixture is heated to 600C. At this temperature and when complete solution is achieved, 13.52 g of 1 ,4-butanediol are added and dissolved. When the solution is completely clear there are added 113.1 of toluene diisocyanate 80/20. The reaction temperature is set at 65-70"C. After one hour0.1g of Sn-ll-octoate are added as a catalyst.

While the viscosity ofthe solution increases, there are added 690g of ethyl acetate. After 5 hours the reaction mixture is cooled. The viscosity ofthe solution is 20000 mPas at 20"C. x = 0.3.

Example 2 In a heatable reaction vessel fitted with a stirrer are added 350g of methyl ethyl ketone and to this solvent are added 266.2839 of a hydroxy-terminated polyester diol which is the condensation product of ethylene glycol and adipic acid with an average molecular weight of 2000. The mixture is heated to 60"C until complete solution is achieved, and 3.600g of 1,4butanediol are then added and dissolved. When the solution is completely clear, there are added 30.1179 oftoluene diisocyanate 80/20. The reaction temperature is set to 65-700C. After one hour 0.1 g of dibutyl tin dilaurate are added as a catalyst. While the viscosity of the solution increases, there are added 3509 of ethyl acetate. After 5 hours the reaction mixture is cooled.

The viscosity ofthe solution is 30000 mPas at 20"C. x = 0.3.

Example 3 Example 2 is repeated using a polyester diol which is the condensation product of 1 ,4-butanediol and adipic acid with an average molecularweight of 2000, and 1,4-butanediol,4,4'-diphenylmethane-diisocyan- ate (MDI) and solvents as follows: polyol 244.4929 1,4-butanediol 6.6109 MDI 48.8989 methyl ethyl ketone 350.0009 toluene 350.0009 x=0.6.

Example 4 Example 2 is repeated using a polyesterdiol which is the condensation product of 1,4-butanediol and adipic acid with an average molecularweight of 2000 (polyol 1) and a polycaprolactone diol with an average molecular weight of 1000 (polyol 2), and further 1 ,4-butanediol, 4,4'-diphenyl - methane - diisocyanate and solvents as follows: polyoll 148.5589 polyol2 56.8049 1,4-butanediol 16.3819 MDI 78.2579 toluene 350.0009 dimethylformamide 350.0009 x= 1.39.

Example 5 Example 2 is repeated using a polyesterdiol which is the condensation product of 1 ,4-butanediol and adipic acid with a molecularweight of 2000, and with 1 4-butanediol, 4,4'-diphenyl-methanediisocyanate and solvents as follows: polyol 210.3779 butane-diol-1,4 16.7799 MDI 72.8449 toluene 350.0009 dimethyl formamide 350.0009 x= 1.77.

Example 6 Example 2 is repeated using a polyesterdiol which is the condensation product of 1,6-hexanediol and adipic acid with a molecularweight of 3000, and 1 ,4-butanediol,4,4'-diphenyl - methane - diisocyanate and solvents as follows: polyol 258.8629 1,4-butanediol 5.1849 MDI 35.9549 dimethyl formamide 200.0009 toluene 300.0009 methyl ethyl ketone 200.0009 x=0.67.

Example 7 Example 2 is repeated using a polyester diol which is the condensation product of 1,6-hexanediol and 1,4-butanediol (in equimoiarquantities) and adipic acid with a molecularweight of 3000, and 1,4butanediol,toluene diisocyanate (TDI) and solvents as follows: polyol 276.6489 1,4-butanediol 2.493g TDI 20.859g dimethyl formamide 200.000g toluene 300.000g methyl ethyl ketone 200.000g x=0.3.

Examples Example2 is repeated using a polyesterdiol which is the condensation product of 1,4-buta 1 4-butanediol and adipic acid with a molecular weight of 1000, and 1 ,4-butanediol, 4,4'-diphenyl - methane - diisocyanate and solvents as follows: polyol 169.915g 1,4-butanediol 23.2339 MDI 106.8529 dimethylformamide 350.000g toluene 350.000g x=1.51.

Example9 A polyurethane composition is produced by mixing the compositions of examples 3 and 8, adding a UV-stabilizer and an antioxydant and diluting with cyclohexanone as follows: composition of example3 380.228g composition of example 8 570.3429 UV-stabilizer: 2-(2'-hydroxy-5'-methylphenyl) benzotriazole 0.950g antioxidant: 2,4-dimethyl-6-t.butylphenol (technical quality) 0.9509 cyclohexanone 47.5309 Example 10 A polyurethane composition is produced by mixing the compositions of examples 4 and 7, adding UV-stabilizer and an antioxidant and diluting with cyclohexanone as follows: composition of example 4 760.456g composition ofexample 7 190.1 14g UV-stabilizer: 2-(2'-hydroxy-3',5'-di-t.

amylphenyl)-benzotriazole 0.950g antioxidant: tetra-[ss-(3',5'-di-t.butyl-4'-hyd roxy phenyl)-propionyl methyl]-methane 0.950g cyclohexanone 47.530g Example ii Example 10 is repeated using the composition of example 6 in place ofthe one of example 7.

Example 12 A polyurethane composition is produced by mixing the compositions of examples 2 and 4, adding a UV-stabilizer and an antioxidant and diluting with cyclohexanone as follows: composition of example 2 700.000g composition of example 4 250.000g UV-stabilizer(as in example 10) 0.950g antioxidant (as in example 10) 0.950g cyclohexanone 47.530g Example 13-16 Example 9-12 are repeated, adding a polyvinyl chloride copolymer as follows: composition ofexample9-12 100.000g PVC-copolymerof 84 weight % of vinyl chloride 15weight% of vinyl acetate and 1 weight% of maleic acid, molecular weight 2000 2.000g and stirring until the copolymer is dissolved.

Analogously as described there is employed a PVC-copolymer of 84 weight % vinyl chloride, 15 weight % vinyl acetate and 1 weight % of maleic acid with a molecularweig ht of 1000 or 3000.

Examples 17-20 Examples 9-12 are repeated, adding a polyvinyl copolymer as follows: composition of example 9-12 100.0009 PVC-copolymer of 60 weight % vinyl chloride and 40 weight % vinyl acetate with molecular weight 4000 5.000g and stirring until the copolymer is dissolved.

Analogously there is employed a vinyl chloride copolymer of 60 weight % vinyl chloride and 40 weight % vinyl acetate with a molecular weight of 2500 or 5500.

Inthefollowing application examples all parts are by weight and the quantities of application ofthe coatings referto g of solid substance per m2 of substrate.

Application example A Undyed split hide of 1.5 mm thickness is coated with two polyurethane base coatings ofthe following composition: 30 parts of hydroxy-terminated polyurethane derived from 3 molar parts of 4,4'-diphenyl -methane diisocyanate, 1 molar part of polyca-prolactone diol of molecularweight3000 and 2 molar parts of 1,4butanediol, 35 parts oftoluene and 35 parts of dimethyl formamide and pigmented with 1 Og/kg oftitanium dioxyde in an application quantity of 509 of solid substance per m2foreach coating and with a polyurethane top-coating (lacquer) ofthe following composition:: 30 parts of polyurea-urethane derived from 2 molar parts of 4,4'-dicyclohexyl - methane -diisocyanate, 1 molarpartofpolycaprolactonediol of molecular weight 3000 and 0.95 molar parts of isophorone diamine and 70 parts of solvent (toluene/ethylene glycol monomethyl ether/isopropanol) in an application quantity of 1 00g of solid substance per m2. The coating compositions are applied with a rollercoateron the splitside and dried aftereach coating in the drying channel at4O to 800C.The so coated substrate is then sprayed by means of a spray pistol with the composition of example 1, diluted with ethyl acetate to a viscosity of1 0-12 sec. in the 4 MM Ford cup, in an application quantity of 1 Og of solid substance per m2 and then dried in the drying channel at 40 to 80 C.

A shoe upper made ofthe so treated leather is bottomed directly, without any roughing or swelling ofthe margin ofthe upper, with a polyurethane integral foam sole by the injection moulding procedure. The temperature at the contact-surface sole/ margin ofthe upper reaches 1 900C. The so made shoe is cooled and then finished and cleaned in the usual way, and isthen readyforuse.

Alternatively the shoe upper is bottomed with polyvinyl chloride synthetic material with an injection moulding temperature of 1 900C.

if in the above example there is used an airless sprayer in place of a spray pistol, the composition is diluted to 12 to 40 seconds viscosity.

Application example B A sheet of polyurethane plastic of 1.5 mm thickness and reinforced on the back witch cotton tricot is coated sequentiallywiththefollowing coatings: first 50g/m2 of a base coating ofthe following composition: 30 parts of hydroxyterminated polyurethane derived from 2.5 molar parts of 4,4'-diphenylmethanediisocyanate, 1.5 molar parts of 1,4-butanediol and 1 molarpartofpolycaprolactone diol of molecular weight of 3000 70 parts of solvent (toluene/dimethyl formamide), then 300g/m2 of an intermediate coating of the following composition:: 83.3 parts of polyurethane diisocyanate derived from 2 molar parts oftoluene diisocyanate and 1 molarpartofpolypropyleneglycol of molecular weight 2000 and 16.7 parts of3,3'-dimethyl -4,4' -dicyclohexyl- methanediamine, white pigmentwith 89 oftitanium dioxyde perkg of composition and then 30g/m2 of a top-coating ofthe following composition: 30 parts of a polyurea-urethane derived from 2 molarpartsofisophoronediisocyanate, 1 molarpart of polycaprolactone diol of molecularweight3000 and 0.95 molar parts of isophorone diamine, 35 parts oftoluene and 35 parts of isopropanol and white-pigmented with 1 Og of titanium dioxide per keg of composition.

The coating compositions are applied by means of a roller coater and after each application the coating is dried at 40 to 140"C. The so treated substrate is coated by means of a rubbercylinderwith the composition of example 1 at 10g/m2 and dried at 80 C. Of this material there is made a shoe upper which is bottomed directly (without any roughing orswelling ofthe margin ofthe upper) with integral polyurethane foam of raw density of 500 kg/m3 by injection moulding. The temperature at the lasted margin ofthe upper rises during the procedure to 160"C. The resulting shoe is, afterthe conventional finishing and cleaning, ready for use.

Application Example C Split hide of 1 mm thickness, coated with two base coats (adhesive coats) as used in the above application example A (total application quantity 150g/m2) and a top coat (lacquer) as used in the above application example A (90g/m2) is coated with the finish bythetransferprocedure. Forthis purpose an embossed paper support is coated with the composition of example 1 at 20g/m2 and this is applied with its coated side on the leather (coated as indicated above).

The coating is transferred at 80 to 11 00C, removing the provisional paper-support. The coated material is used to make a shoe upper as described in application example A, which is then bottomed with polyvinyl chloride compound at 200 C, cooled and finished as usual.

According to a modified procedure the support paper may be coated with all of the above polyurethane coatings in inverse sequence (1 stthe composition of example 1,2nd the lacquer coating, 3rd and 4to the base coatings) and dried after each of the first, second and third coatings but not after the fourth coating and then transferred onto the leat her at 80 t6 11 0 C; the coated leather is then worked to a shoe as described above.

Application example D Split hide upper leather is coated and worked to a shoe upper as described in application example C and then the lasted margin ofthe upper leather is further coated with a layer ofthe composition of example 1 at 20g/m2. A preformed polyurethane sole is coated with the composition of example 1 at 20g/m2 without completely drying the coating, heated to 70"C by IR-shock-reactivation and immediately bonded to the upper. Upon cooling the shoe isfinished in the usual way and is then ready for use.

Application example E Buffed calfleatherof 1.8 mm thickness, coated with base and lacquer coatings as described in example C is coated by means of a curtain coaterwith the composition of example 1, which is diluted with ethyl acetate to a viscosity of 20 seconds Ford-cu p 4 mm, at 20g/m2 and dried at 80-85 C. Of the coated leather there is made a shoe upperwhich is bonded by reactivating at85 C by means of an AGO-machine directly without any roughing orswelling ofthe margin and without any additional adhesive on the margin, with a preformed polyvinyl chloride sole, coated with the solvent-containing composition of example 1 applied at 30g/m2. The shoe is finished in the usual way.

Application example F The procedure of example E is repeated; however, before bonding the upper with the sole, an additional layer of the composition of example 1 is applied at 100g/m2onthe margin ofthe lasted upper.

Analogously as the composition of example 1 the compositions oftheexamples 2,3,6,7,9,10,11,12, and 13to 20 are used inthe above application examples.

Claims (16)

1. Processfortheproduction offootwearwith polyurethane coated uppers and thermally bonded sole wherein the shoe upper material is coated, before making the pattern, with a hydroxy-terminated polyurethanethat contains ether and/or ester group- ings and has a glass-transition temperature below 200"C and, afterfitting and lasting, the upper is bonded directlyto the sole by heattreatment at temperatures of at least 50"C.

2. Process according to claim 1, wherein the hydroxy-terminated polyurethanes are products obtainable by polyaddition of (a) at least one polyisocyanate with (b) at least one polyether and/or at least one polyester polyol with an average molecular weight in the range of from 300 to 4000 and optionnally (c) at least one low molecular polyfunctional isocyanate-reactive component wherein per equivalent of component (b) there are employed 0.8 to 0.9995 equivalents of component (a).

3. Process according to claim 2,wherein per equivalent of component (b) there are employed x equivalents of component (c) and (y+x) equivalents of component (a), whereinxis0to 1 andy is 0.8 to 0.9995.

4. Process according to claim 2 wherein a polyurethane as defined in claim 3 is employed in admixture with a hydroxy-terminated polyurethane, obtainable by polyaddition ofthe component (a), (b) and (c), defined as in claim 3, and wherein y is as defined in claim 3 butx is a numbergreaterthan 1.

5. Process according to any ofclaims 1 to 4 wherein the hydroxy-terminated polyurethane is employed in admixture with a copolymerofvinyl chloride and vinyl acetate and optionally and unsaturated dicarboxylic acid.

6. Process according to any ofthe claims 1 to 5 wherein the hydroxy-terminated polyurethane, optionally in admixture with the vinyl chloride copolymeris used intheform of a solution in an inert organic solventthat is volatile under application conditions.

7. Process according to any of claims 1 to 6 wherein the upper material is a coated material selected from polyvinyl chloride, polyurethane, split leather or buffed leather.

8. Process according to claim 7 wherein the coating consists of at least one base coat and at least one top coat and optionally an intermediate coat between base and top coat, each of which is polyurethane based.

9. Process according to any of claims 1 to 8 wherein an additional layer ofthe hydroxy-terminated polyurethane defined in any of claims 1 to 7 is applied on the margin ofthe shoe upperto be bonded.

10. Process according to any of claims 1 to 9 wherein forthe bonding of preformed soles, these are coated with a hydroxy-terminated polyurethane composition as defined in any of claims 1 to 7.

11. Process according to any of claims 1 to 10, wherein the heattreatment is carried out in the range of 50 to 11 00C if at least one polyurethane layer contains a solvent.

12. Process according to any of claims 1 to 10, wherein the heat treatment is carried out attemperatures of at least 1 000C when there is practically no solvent present.

13. Process according to any of claims 1 to 9,11 and 12, wherein the uppers are bottomed with synthetic soles by direct or injection moulding at temperatures in the reactivation range of the outer coating of the upper.

14. Footwear produced by the process of any of claims 1 to 13.

15. Process according to any of claims 1 to 14 and as described in any of examples A to F.

16. Footwearaccordingto claim 14,whenever produced bya process of any of the examplesAto F.