JPH0347202A - Sole of shoe made of polyurethane resin, and manufacture of it - Google Patents

Abstract

PURPOSE:To improve moisture and heat-resisting properties by employing polyurethane resin specified tensile strength and abrasion loss to manufacture soles. CONSTITUTION:Soles for shoes are manufactured by reacting and hardening a mixture of high reactive materials including poloxyalkylenpolyol in a mold, and is made of polyurethane resin having not less than 60kg/cm<2> of tensile strength in conformity to JIS-K-6301, and 150mg or less of abrasion loss in conformity to JIS-K-7311. Thus, a sole of shoe can be obtained which has advanced moisture and heat resisting properties, and higher those than the conventional ester polyurethane made sole, of course, and much higher than ether polyurethane made sole.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a polyurethane resin shoe sole having excellent physical properties such as heat and humidity resistance, and a method for manufacturing the same.

[Prior art] Compared to regular rubber, polyurethane resin is being used for shoe soles instead of rubber because of its simpler manufacturing process and superior abrasion resistance. . As the main raw material polyol for polyurethane resins, polyester polyols are used from the viewpoint of mechanical properties and abrasion resistance, as described in JP-A-59-27911, but ester bonds are easily hydrolyzed ( , poor hydrolysis resistance.To improve this point, 3-methyl-1,5
Polyester polyols using -bentanediol are also known (Japanese Unexamined Patent Publication No. 63-101412), but as long as they are basically ester bonds, they are susceptible to hydrolysis.

[Problems to be Solved by the Invention] In order to solve the problem of hydrolysis resistance of polyester polyols, it is also known to use polyoxyalkylene polyols. Shoe soles made of polyurethane resin (hereinafter also referred to as ether polyurethane) that use polyoxyalkylene polyols also have the characteristic that they are less likely to grow mold than those that use polyester polyols. Compared to polyurethane-based resins using polyester polyols (hereinafter also referred to as ester-based polyurethanes), ether-based polyurethanes have superior moisture and heat resistance, but the difference is not very significant, and in addition, Currently, physical properties such as strength and abrasion resistance are inferior. Therefore, soles made of ether-based polyurethane are only used in applications where heat and humidity resistance is a problem, and their resistance to moisture and heat is not necessarily sufficient.

[Means for Solving the Problems] The present invention is based on the discovery of an ether-based polyurethane that has abnormally high moisture and heat resistance by using a specific polyoxyalkylene polyol. In addition, physical properties such as tensile strength and abrasion resistance, which were significantly inferior to ester-based urethanes, have also been improved.
It has extremely excellent physical properties as a shoe sole. Ester-based urethane shoe soles are manufactured by first manufacturing thermoplastic ester-based urethane and then molding it. On the other hand, as a method for molding polyurethane, a one-shot method is simple, and a reaction injection molding method abbreviated as RIM is particularly advantageous in terms of molding efficiency. However, it is difficult to mold ester-based urethane using such a molding method.

The present invention has discovered a polyurethane resin which is an ether polyurethane molded by a one-shot method, particularly a reaction injection molding method, and which has extremely excellent physical properties for use as a shoe sole as described above. The present invention is the following invention which aims at this technical improvement.

It is obtained by reaction-curing a highly reactive raw material mixture containing polyoxyalkylene polyol in a mold, and is rated according to JIS-
Tensile strength according to 6301 is 60Kg/cm” or more,
The wear amount according to JIS-7311 is 150m.
A shoe sole made of polyurethane resin with a weight of less than g.

In the Demacha bending test after being left at 80°C and 95% relative humidity for 10 days, the 2 mm initially cut
Shoe soles made of polyurethane resin that do not allow cracks to grow larger than 5+ nm.

A mold is made of a mixture containing a high molecular weight polyol whose main component is a highly reactive polyoxyalkylene polyol with a low degree of unsaturation, a chain extender, and a diphenylmethane diisocyanate-based polyisocyanate compound and additives such as a blowing agent and catalyst. A method for manufacturing a polyurethane resin shoe sole with excellent physical properties such as heat and humidity resistance, which is characterized by reaction curing in a medium.

The polyurethane resin in the present invention is a polyurethane resin obtained by reaction-curing a highly reactive raw material mixture in a mold. The method for manufacturing polyurethane resin molded products by reaction-curing a highly reactive raw material mixture in a mold is as follows:
This is injection molding using the one-shot method. In particular, methods using mixtures of highly reactive raw materials are called RIM.

This method is used in the production of ether-based polyurethane molded products and is not used in the production of ester-based polyurethane molded products. This ether polyurethane in the present invention has extremely high wear resistance as shown in the Examples below.

That is, the amount of wear based on JIS-7311 is extremely low. Moreover, the tensile strength according to JIS-6301 is high. These abrasion resistance and tensile strength are comparable to ester polyurethane. On the other hand, the polyurethane resin in the present invention is used at 80°C and 95%
Passes the Demacha flex test after being left under relative humidity for 10 days. In conventional ester polyurethane, 4
Most of the samples failed after being left in the sun. Most conventional ether-based polyurethanes fail after being left for 6 to 7 days. On the other hand, the ether polyurethane of the present invention has surprising heat and humidity resistance, passing the test even after being left for 20 days. In addition, ester-based urethane has low mold resistance and is difficult to use in an atmosphere where mold easily grows, but the ether-based polyurethane of the present invention also has excellent mold resistance, which is a characteristic of ether-based polyurethane.

The ether-based polyurethane in the present invention is a low-foam polyurethane having the same density as conventional shoe soles, and the polyoxyalkylene bool, which is a raw material for conventional ether-based polyurethane, is replaced with the specific highly reactive polyoxyalkylene bool in the present invention. It can be easily produced by changing to polyol. Highly reactive polyisocyanate compounds are also used, particularly diphenylmethane diisocyanate-based polyisocyanate compounds. That is, it is obtained by reaction-curing a specific highly reactive polyoxyalkylene polyol, a chain extender, and a diphenylmethane diisocyanate-based polyisocyanate compound in the presence of a blowing agent and a catalyst. The polyoxyalkylene polyol in the present invention has an oxyethylene group at the end, and has a hydroxyl value of 40 or less, particularly 5 to
30, and is a polyoxyalkylene polyol with a particularly low degree of unsaturation.

Generally speaking, the lower the hydroxyl value of a polyoxyalkylene polyol, the higher its degree of unsaturation. Because the amount of oxyalkylene groups, especially oxypropylene groups in There are many (side reactions) (
This is because the degree of unsaturation increases. This side reaction of alkylene oxide having 3 or more carbon atoms is likely to occur when the reaction catalyst is an alkali catalyst such as an alkali metal compound (alkali hydroxide). It is not impossible to produce a polyoxyalkylene polyol with a low degree of unsaturation and a low hydroxyl value using an alkaline catalyst (it is considered possible, especially if mild reaction conditions are used), but it is preferable to use other catalysts. Preferred are polyoxyalkylene polyols produced by. Examples of this catalyst include metal porphyrin (see JP-A-61-197631), LiPFa
(see JP-A-60-197726), composite metal cyanide complexes (see JP-A-59-15336, U.S. Pat. No. 3,929,505), complexes of metals and chelating agents with tridentate or higher coordination. (Unexamined Japanese Patent Publication No. 60-197726
(Refer to the Publication No.).

In the present invention, the degree of unsaturation of the polyoxyalkylene polyol must be considered in relation to the hydroxyl value. The upper limit of unsaturation is 0.07 when the hydroxyl value is 40 or less.
It is necessary that it is meq/g. In particular, the upper limit of the degree of unsaturation is preferably 0.04 meq/g. The degree of unsaturation of polyoxyalkylene polyols produced using conventional alkali catalysts is 0.08 or more with a hydroxyl value of about 56, and when the hydroxyl value falls below this, the degree of unsaturation increases rapidly. In other words, the higher the hydroxyl value, the lower the degree of unsaturation. Even if a catalyst other than an alkali catalyst such as the multi-metal cyanide complex catalyst is used, the degree of unsaturation tends to increase as the hydroxyl value decreases. Therefore, in the polyoxyalkylene polyol of the present invention, the higher the hydroxyl value, the lower the degree of unsaturation must be.

When this relationship is expressed by a formula, the degree of unsaturation (y meq/g) of the polyoxyalkylene polyol having a hydroxyl value (x) preferably satisfies the following relationship: y≦0.9/(x-10). Here, X is about 22
．． For 9 or less, the upper limit of y is 0.07 meq/g.

Preferably, the upper limit of y is 0.04 meq/g (
When X is about 32.5 to 40, y follows the above formula). Also,
The number of hydroxyl groups per molecule is preferably 2 to 8, particularly 2 to 8.
6 is preferred. In addition, it goes without saying that the polyoxyalkylene polyol in the present invention may be a mixture of two or more types, and in that case, the average degree of unsaturation, hydroxyl value,
and the range of the number of hydroxyl groups are as described above.

The above polyoxyalkylene polyol is produced by adding an alkylene oxide to a polyvalent initiator, and the alkylene oxide is preferably propylene oxide, a small amount of butylene oxide (both one type and ethylene oxide are used). .Particularly preferably,
Propylene oxide and ethylene oxide are used. The hydroxyl groups in this polyether polyol contain a high proportion of highly reactive hydroxyl groups, that is, primary hydroxyl groups. For this purpose, an oxyethylene group must be present at the end of the molecular chain of the polyoxyalkylene polyol.

Such a polyoxyalkylene polyol can be obtained by adding propylene oxide or butylene oxide to a polyvalent initiator and then adding ethylene oxide. The oxyethylene group may be present not only at the terminal portion of the molecular chain but also within the molecular chain. The content of oxyethylene groups present in the terminal portion of the molecule is required to be at least 5% by weight, and preferably as low as 8% by weight.

The upper limit is preferably 40% by weight, especially 30% by weight. On the other hand, the total content of oxypropylene groups and oxybutylene groups is preferably 60% by weight or more, particularly 70% by weight or more.

The polyhydric initiators used in producing the above-mentioned polyoxyalkylene polyols include polyhydric alcohols, polyhydric phenols, polyamines, alkanolamines, and the like. For example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, pentaerythritol, diglycerin, dextrose, sucrose, bisphenol. A, ethylenediamine, etc. These may be used alone or in combination of two or more. Particularly preferred polyhydric initiators are polyhydric alcohols. These polyvalent initiators include propylene oxide, 1,2- or 2-
．． At least one alkylene oxide having 3 or more carbon atoms such as 3-butylene oxide is added, and then ethylene oxide is added to obtain the desired polyoxyalkylene polyol. A polyoxyalkylene polyol having an internal oxyethylene group is obtained by adding ethylene oxide and an alkylene oxide having 3 or more carbon atoms sequentially or in a mixture to a polyvalent initiator, and adding ethylene oxide in the final step.

The polyoxyalkylene polyol of the present invention may further contain a polymer of a monomer having an α,β-unsaturated group. This polymer-containing polyoxyalkylene polyol is called a polymer/polyol, etc. It is obtained by polymerizing monomers such as acrylonitrile and styrene in the polyoxyalkylene polyol. The polymer is dispersed in the polyoxyalkylene polyol in the form of fine particles, and is usually stably dispersed in the polyoxyalkylene polyol. The amount of polymer in the polymer-containing polyol is usually up to 40% by weight, especially from 5 to 30% by weight.

The overall hydroxyl value of this polymer-containing polyoxyalkylene polyol is preferably 40 or less, particularly preferably 5 to 30.

In the present invention, high molecular weight polyols other than the polyoxyalkylene polyols and other high molecular weight active hydrogen compounds can be used in combination as optional components, but their use is not essential. In addition, the amount thereof is large (usually 30% by weight or less based on the polyoxyalkylene polyol). However, for the purpose of improving the physical properties of the polyurethane resin,
Or it can be used for other purposes. As such a high molecular weight polyol, a polyol having an average molecular weight per hydroxyl group of 400 or more, particularly 800 or more, and an average number of hydroxyl groups per molecule of 1.6 to 4 is preferable.

The average molecular weight per hydroxyl group is preferably 10.000 or less. Examples of such high molecular weight polyols include hydroxyl group-containing hydrocarbon polymers such as hydroxyl group-containing polybutadiene, polyester polyols, and polyoxytetramethylene polyols.

In the present invention, a polyol chain extender or an amine chain extender is used as the chain extender. Two or more types of chain extenders may be used in combination. As a polyol chain extender, 2
It is a low molecular weight polyol having ~4 hydroxyl groups and a molecular weight of 400 or less. The chain extenders include typical chain extenders such as ethylene glycol and 1,4-butanediol.

In addition, there are polyols that do not have amino groups, such as polyhydric alcohols other than those mentioned above, low molecular weight polyoxyalkylene polyols, and polyols that have tertiary amino groups. Two or more of these can be used in combination. Examples of the polyol chain extender include, but are not limited to, the compounds listed below. Preferably, at least one of ethylene glycol and 1,4-butanediol is used.

Ethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, triethanolamine, N-alkyljetanolamine, bisphenol A-alkylene oxide adduct, Glycerin, trimethylolpropane.

Examples of the amine chain extender include aromatic polyamines, aliphatic polyamines, alicyclic polyamines, and primary or secondary alkanolamines. Examples of aromatic diamines include aromatic diamines having at least one substituent selected from alkyl groups, cycloalkyl groups, alkoxy groups, alkylthio groups, and electron-withdrawing groups on the aromatic nucleus to which an amino group is bonded. Particularly preferred are diaminobenzene derivatives (eg, diethyltoluenediamine and monochlorodiaminobenzene) and diphenylmethanediamine derivatives. It is preferable that 2 to 4 of the above-mentioned substituents other than the electron-withdrawing group are bonded to the aromatic nucleus to which the amino group is bonded, and in particular, at least one ortho position to the bonding site of the amino group, preferably all Preferably, they are bonded. Preferably, one or two electron-withdrawing groups are bonded to the aromatic nucleus to which the amino group is bonded. Of course, the electron-withdrawing group and other substituents may be bonded to one aromatic nucleus.

The number of carbon atoms in the alkyl group, alkoxy group, and alkylthio group is preferably 4 or less, and the cycloalkyl group is preferably a cyclohexyl group.

As the electron-withdrawing group, a halogen atom, a triheromethyl group, a nitro group, a cyan group, an alkoxycarbonyl group, etc. are preferable, and a chlorine atom, a trifluoromethyl group, and a nitro group are particularly preferable. As the aliphatic polyamine, diaminoalkanes and polyalkylene polyamines having 6 or less carbon atoms are preferred. Further, aromatic compounds having two or more aminoalkyl groups, aromatic compounds having two or more aminoalkyl groups in total (e.g. xylylene diamine),
It is also possible to use polyamines having an aromatic nucleus, such as these aromatic compounds having the above-mentioned substituents. Examples of aliphatic polyamines include alkylene diamines, polyalkylene polyamines, and polyamines obtained by converting part to all of the hydroxyl groups of low molecular weight polyoxyalkylene polyols into amino groups. Examples of aliphatic polyamines include cycloalkanes having two or more amino groups and/or aminoalkyl groups (for example, inphorondiamine), and examples of alkanolamines include monoethanolamine and jetanolamine.

The amount of the chain extender component based on the total of the entire high molecular weight polyol component including the polyoxyalkylene polyol and the chain extender component is 2 to 45% by weight. Preferably, 5 to 30% by weight is employed.

The polyisocyanate compound component consists of at least one compound having at least two isocyanate groups. Preferably, a highly reactive aromatic polyisocyanate is used.

Specifically, a diphenylmethane diisocyanate-based polyisocyanate compound consisting of one or more of diphenylmethane diisocyanate, polymethylene polyphenylisocyanate, and modified products thereof is used. Preferably, a liquid modified product of 4,4'-diphenylmethane diisocyanate is used. Examples of modified products include prepolymer-type modified products and carbodiimide-modified products. As the diphenylmethane diisocyanate-based polyisocyanate compound, diphenylmethane diisocyanate modified with polyoxyalkylene polyol is preferred.

As this polyoxyalkylene polyol, a polyoxyalkylene polyol having a hydroxyl value of 600 or less, particularly 400 or less is preferable. Although there is no particular lower limit to the hydroxyl value, the aforementioned specific low unsaturation polyoxyalkylene polyols can also be used. Polyisocyanates modified with these polyoxyalkylene polyols are one type of the above-mentioned prepolymer-type modified products, and are also sometimes called isocyanate group-terminated polyurethane polymers. The isocyanate group content of the polyisocyanate compound is preferably small (both are preferably 12% by weight, and particularly small (12% by weight)).
Both are preferably 16% by weight. The amount of the polyisocyanate compound component used is 0.8 to 1.3 times the equivalent of the total equivalent of the polyol component and chain extender component.

Preferably, 0.9 to 1.2 equivalents are used.

The use of catalysts is usually essential in the production of polyurethane resins. As a catalyst, a tertiary amine catalyst or an organic tin compound is usually used, and a blowing agent is used in the present invention to improve the filling properties of the reactive mixture into a mold. Low-foaming polyurethane resins can be obtained using relatively small amounts of blowing agents.As blowing agents, trichlorofluoroethane (R-11), 1,1
．． 2-Trichloro-1,2,2-trifluoroethane (
R-113), 1,1-dichloro-2,2゜2-trifluoroethane (R-123), 1,1-dichloro-
1-fluoroethane (R-141b), methylene chloride,
There are other halogenated hydrocarbon blowing agents and water, and both are often used in combination. In particular, it is preferable to use a halogenated hydrocarbon blowing agent, and the amount thereof is about 10 parts by weight or less per 100 parts by weight of the total of polyol and chain extender.
Particularly suitable is about 0.1 to 5 parts by weight.

Polyurethane resins are produced using optional additives in addition to the above raw materials.

Optional additives include, for example, foam stabilizers, filler 1 colorants, ultraviolet absorbers, light stabilizers, antioxidants, flame retardants, and the like. Examples of foam stabilizers include silicone foam stabilizers and fluorine-containing foam stabilizers. Fillers include inorganic fibers such as glass fiber and wollastonite, and organic fibers such as synthetic fibers.

These include calcium carbonate, other powder fillers, mica, and other tabular fillers. The amount of these fillers to be filled is preferably about 30% by weight or less, particularly 20% by weight or less, based on the total synthetic resin raw material, since problems arise with the viscosity and operability of the raw material components as the amount increases.

The density of the polyurethane resin in the present invention is 0.2 to 0.
．． 9 g/cm" is preferable. In particular, 0.3
~0.8 g7cm" is preferred.

Note that this density is the density without including a large amount of arbitrary additives such as fillers, and in other cases, the density may be higher. Further, the density of the polyurethane resin in the present invention may exceed 0.9 g/cm'' (or may be a substantially non-foamed polyurethane resin).

The sole of the present invention is preferably molded by a one-shot injection molding method. In this method, the above-mentioned reactive raw materials are mixed in a mixing head, the mixture is injected into a mold, and the mixture is reacted and cured in the mold to obtain a molded article.

In particular, a method of mixing and injecting materials at high speed using highly reactive raw materials is called RIM. It usually takes less than 10 seconds from mixing to the end of filling, and for RIM, it takes less than a few seconds.

The present invention will be explained below with reference to examples, but the present invention is not limited to these examples.

EXAMPLE The following polyol was used to mold shoe soles and evaluate polyurethane foam.・Polyol A: Oxyethylene groups obtained by reacting propylene oxide with low molecular weight polyoxypropylene glycol using the above-mentioned known multimetal cyanide complex, and subsequently reacting ethylene oxide with an alkali catalyst make up 23% of the total oxyethylene groups. A polyoxyalkylene diol with a hydroxyl value of 28 and an unsaturation degree of 0.014 meq/g, which accounts for % by weight.

Polyol B: hydroxyl value 26.5, with oxyethylene group accounting for 20% by weight of the total, obtained by reacting a low molecular weight polyoxypropylene triol with propylene oxide and ethylene oxide in this order by the same method as polyol A; Polyoxyalkylene triol with unsaturation degree C1,019 meq/g.

Polyol C: A polyoxyalkylene triol obtained by the same method as polyol A, in which oxyethylene groups account for 15% by weight of the total, a hydroxyl value of 1665, and a degree of unsaturation of 0.021 meq/g.

Polyol D (conventional polyoxyalkylene polyol): Obtained by reacting propylene oxide and ethylene oxide in this order using KOH as a catalyst, oxyethylene group content 20% by weight, hydroxyl value 28, degree of unsaturation 0.10 meq /g of polyoxyalkylene diol.

Polyol E (conventional polyoxyalkylene polyol): obtained by reacting glycerin with propylene oxide and ethylene oxide in this order in the same way as polyol C, oxyethylene group content 20% by weight, hydroxyl value 24, degree of unsaturation. 0.1
5 meq/g polyoxyalkylene triol.

Polyol F (polyester polyol) molecular weight 30
00 polyethylene adipate diol polyol liquid A polyol mixture (composition is expressed in parts by weight, average unsaturation degree of the polyol mixture is expressed in meq/g),
Water, 1,4-butanediol (BD), silicone foam stabilizer 5F-1306 (manufactured by Shin-Etsu Chemical), Dabco 33
LV (manufactured by Nippon Air Products), dibutyl tin dilaure) (DBTDL), 1,1,2-trichloro-
A homogeneous mixture of 1,2,2-)-rifluoroethane (R-113) (composition is expressed in parts by weight) is used as a polyol.
It was night.

Isocyanate liquid 4,4-diphenylmethane diisocyanate modified with polyoxypropylene diol having a molecular weight of 2000 (modified MDI, isocyanate content 19% by weight).

molding A shoe sole was molded using a low-pressure foaming machine under the following conditions.

Machine rotation speed: 5000 rpm Liquid temperature: 35°C for both liquids Discharge mixing ratio: Polyol liquid/isocyanate liquid: 10
0/92 Discharge amount, 45 g 7 seconds Mold temperature: 45°C Oven temperature: 45°C On the other hand, in order to measure the physical properties of polyurethane resin, aluminum molds (200 mm x 3
00 mm x 9 mm) to form a sheet.

After curing in an oven for 4 minutes (in Comparative Examples, curing time of 4 minutes was insufficient and deformation occurred after demolding, so the setting was 6 minutes in Comparative Example 1.2 and 5 minutes in Comparative Example 3),
The material was aged for 4 days in a room at 23° C. and 60% relative humidity, and its physical properties were measured. The results of the tensile strength according to JIS-6301, the amount of wear according to JIS-7311, and the Dematcher bending test described below are shown in the table.

A rectangular sample of 125 mm x 25 mm was cut out from the sheet formed above, a through hole of 2 mm in the width direction was made in the center, and after keeping it at 80°C and 95% relative humidity for a certain period of time, it was taken out and subjected to a Demacha bending test. I did it. That is, after bending the through hole portion (300 times/min) 10,000 times, crack growth of 5 mm or less was considered a pass, and the bending resistance after heating was evaluated based on the number of days until the test was rejected.

[Effects of the Invention] The polyurethane resin shoe sole of the present invention has extremely excellent moisture and heat resistance, and has much higher moisture and heat resistance than conventional ester polyurethane soles as well as ether polyurethane soles. ing. Moreover, other physical properties of conventional ether-based polyurethane shoe soles are improved, making it an extremely excellent shoe sole.

Claims (1)

[Claims] 1. Obtained by reaction-curing a highly reactive raw material mixture containing polyoxyalkylene polyol in a mold, and complying with JIS-
Tensile strength according to K-6301 is 60Kg/cm^2
or more, and the amount of wear based on JIS-K-7311 is 1
A shoe sole made of polyurethane resin containing 50 mg or less. 2. In the Demacha bending test after being left at 80°C and 95% relative humidity for 10 days, 2.
A shoe sole made of polyurethane resin that does not allow cracks to grow larger than 5 mm. 3. Density of polyurethane resin is 0.2 to 0.9 g/c
The shoe sole according to claim 1 or 2, wherein the shoe sole has a diameter of m^3. 4. The shoe sole according to claim 1 or 2, wherein the polyurethane resin is a reaction product of a highly reactive polyoxyalkylene polyol with a low degree of unsaturation, a chain extender, and a diphenylmethane diisocyanate-based polyisocyanate compound. 5. Polyoxyalkylene polyol has a hydroxyl value of 40
Oxypropylene group and/or oxybutylene group content with an oxyethylene group at the end: 60% by weight
5. The shoe sole according to claim 4, which is one of the above polyoxyalkylene polyols and is a low unsaturation polyoxyalkylene polyol having an unsaturation degree of 0.7 meq/g or less. 6. A mixture containing a high molecular weight polyol whose main component is a highly reactive polyoxyalkylene polyol with a low degree of unsaturation, a chain extender, and a diphenylmethane diisocyanate-based polyisocyanate compound and additives such as a blowing agent and a catalyst. A method for manufacturing a polyurethane resin shoe sole with excellent physical properties such as heat and humidity resistance, which is characterized by reaction curing in a mold. 7. Density of polyurethane resin is 0.2 to 0.9 g/c
7. The method for manufacturing a polyurethane resin shoe sole according to claim 6, wherein the polyurethane resin shoe sole is m^3. 8. Polyoxyalkylene polyol has a hydroxyl value of 40
Oxypropylene group and/or oxybutylene group content with an oxyethylene group at the end: 60% by weight
7. The method for producing a polyurethane resin shoe sole according to claim 6, wherein the polyoxyalkylene polyol is one of the above polyoxyalkylene polyols and has a low unsaturation degree of 0.07 meq/g or less.