JPS61128903A - Shoe sole - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a shoe sole made of stabilized polyurethane resin. More specifically, the present invention relates to a shoe sole made of polyurethane resin that is extremely stable against external factors such as light, heat, moisture, and oxygen.

[Prior Art] Polyurethane is a polymer that has excellent impact resistance, chemical resistance, abrasion resistance, cold resistance, etc., so it has traditionally been a material used in various fields and applications. . However, on the other hand, polyurethane also has the property of being easily affected by external factors such as light, heat, moisture, and oxygen, and these external factors can cause deterioration of the surface condition of polyurethane molded products. That is, phenomena undesirable for the quality of the polyurethane product occur, such as surface peeling, cracking, and changes in hue.

For this reason, various stabilizers have been developed for the purpose of improving polyurethane's poor weather resistance against these external factors. For example, in JP-A-56-100848, phenylenediamine compounds and sterically hindered phenol compounds, phenylenediamine compounds and phosphite compounds, phenylenediamine compounds and quinoline compounds, phenylenediamine compounds and benzotriazole A phenylenediamine compound and a thiourea compound, a phenylenediamine compound and a piperidine compound, or a phenylenediamine compound and a metal oxide are used as stabilizers for polyurethane. or,
In JP-A-57-49653, a hindered phenol compound and a phosphorous acid ester are used to improve the weather resistance of polyurethane.

A variety of molded products are manufactured using polyurethane containing these stabilizers.Recently, polyurethane resins are being used to manufacture various automobile parts, garden chairs, and other products that utilize the design freedom and corrosion resistance of polyurethane resins. Great products are being manufactured.

[Problems to be solved by the invention] However, when the polyurethane resin is an uncolored white polyurethane, the polyurethane resin produced using the stabilizers that have been developed so far has a problem with its whiteness. Polyurethane resins have not always been satisfactory in terms of sustainability. That is, JP-A-56-100848
Although the stabilizer disclosed in the publication serves the purpose of preventing colored polyurethane from shrinking or cranking, it contains a phenylenediamine compound as an essential component, so it cannot be used with white polyurethane. If used for this purpose, yellowing will occur and this is not desirable.

Furthermore, the stabilizer disclosed in JP-A No. 57-49653 is inferior in terms of sustainability of effect;
It cannot be said to be sufficient.

As mentioned above, various stabilizers for polyurethane are being developed for the purpose of producing polyurethane resins with excellent stability that can withstand long-term use.
This is still not sufficient, and there is a strong desire for the emergence of polyurethane products with excellent weather resistance that can withstand long-term use.

In particular, when polyurethane resin is used for shoe soles, if the polyurethane has the property of yellowing or peeling, the commercial value of the shoe itself will be significantly reduced, which is inconvenient. There is a need for shoe soles made of polyurethane resin that will not discolor or fade.

[Means for Solving the Problems] In order to solve the above-mentioned problems, particularly the problem that there is no shoe sole made of polyurethane that is resistant to discoloration and fading on the market, the present inventors have: As a result of intensive studies, we have arrived at the present invention. That is, the present invention provides: (a) an ultraviolet absorber, (b) an antioxidant, and (c) general formula (I) (R+, Rz, and R3 are the same or different alkyl groups,
cycloalkyl group, aryl group, alkylaryl group,
Represents an aralkyl group. ) and which is made of a polyurethane resin blended with a phosphite having a phosphorus content in the range of 4.0 to 14.0% by weight, and is resistant to discoloration and gloss.

The polyurethane resin used to manufacture the sole of the present invention is manufactured using an isocyanate compound and an active hydrogen-containing compound, and at that time, an ultraviolet absorber, an antioxidant, and the above-mentioned A phosphite compound represented by the general formula (I) is used as a stabilizer.

Examples of the ultraviolet absorber that can be used in the present invention include generally known ultraviolet absorbers such as salicylic acid derivatives, benzophenone derivatives, benzotriazole derivatives, nitrile derivatives, and oxalic acid anilide derivatives. Most preferred for use are benzotriazole derivatives. Specific examples of benzotriazole derivatives include 2-(2″-hydroxy-5″-methylphenyl)benzotriazole,
2-(2'-hydroxy-5'-t-butylphenyl)
Benzotriazole, 2-(2'-hydroxy-3', 5'-di-t-butylphenyl) Benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-
methylphenyl)-5-chlorobenzotriazole, 2
- (2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriazole, 2-(2
Examples include "-hydroxy-3", 5'-dialkylphenyl)benzotriazole.

The above ultraviolet absorbers can be used in the present invention alone or as a mixture of two or more.

Next, as the antioxidant that can be used in the present invention, any hindered phenol compound having at least one branched lower aliphatic hydrocarbon group bonded to the ortho position may be used, but among them, 1 phenolic nucleus
One having 1 to 4 in the molecule is preferred. When two or more phenol nuclei are present in one molecule, there are no particular restrictions on the bonding state. The branched lower aliphatic hydrocarbon group mentioned above is generally preferably one having 3 to 7 carbon atoms, such as isopropyl group, isobutyl group, t
-butyl group, isopentyl group, t-pentyl group, isohexyl group, etc., but particularly preferred ones are t-
It is a butyl group. Various other substituents may be bonded to the above-mentioned hindered phenol compound. Specific examples of the above-mentioned hindered phenol compounds include the following compounds and metals.

The above antioxidants can be used in the present invention alone or as a mixture of two or more.

Next, the phosphite ester compound represented by the general formula (I) is a compound represented by the general formula (I) in which R1, R2, and R1 satisfy the above conditions. Any type of material may be used, but the phosphorus content should be 4.0 to 14.
．． 0% by weight, and 6.0-8.0% by weight is particularly preferred. Specific examples of these include triisodecyl phosphite, phenyl diisodecyl phosphite, diphenylnonylphenyl phosphite, and triisooctyl phosphite.

These phosphite esters can be used in the present invention alone or as a mixture of two or more.

The phosphorus content of the phosphite used in the present invention is
Although it can be obtained by simple calculation, it can be obtained experimentally as follows.

(I) Preparation of test solution 0.1 g of sample (containing 4 to 16 B as phosphorus) was accurately weighed into a 100 ml Kjeldahl flask, and before adding 2 ml of concentrated sulfuric acid and heating to carbonize, 1 g of 30% hydrogen peroxide solution was added. Add drop by drop to decompose the solution until it becomes clear, then ignite until white fumes of sulfuric acid come out. After cooling, pour this solution into 100 m
Transfer to a volumetric flask and add water up to the marked line to use as the test solution.

(2) Creating a calibration curve Pour 0.2, 4, 6.8 ml of phosphorus standard solution (4.3939 g of monopotassium phosphate dissolved in water to make 11) into a 100 ml volumetric flask, and add 50 ml of water to each.
Add m1. Molybdovanadate solution 20
Add water to bring the total volume to 100 ml, and leave it for 30 minutes. This solution was transferred to a 10 mm cell and 400 nm
Measure the absorbance at 100°C using the blank test solution as a control solution, and create a calibration curve.

(3) Pour 5 ml of the measurement test liquid into a 100 ml volumetric flask, and
Add 0 ml and 20 ml of molybdovanadate solution, perform the same procedure as for creating a calibration curve, and measure the absorbance.
Calculate the phosphorus content% from the calibration curve.

The amount of the stabilizer used in the present invention is not particularly limited and is arbitrarily determined depending on the conditions in which the polyurethane composition is used, but usually both the ultraviolet absorber and the tertiary phosphite are added to the polyurethane. It ranges from 0.05 to 5% by weight, preferably from 0.1 to 3% by weight. If the amount added is less than this range, the stabilizing effect will be low, and if it is more than this range, the physical properties such as strength and elongation of the product will be lowered, which is not preferable.

Regarding the method of adding the stabilizer used when manufacturing the sole of the present invention, it is preferable to disperse the stabilizer in advance into a part of the raw material for producing polyurethane or to dissolve it by heating. It is preferable to blend the phosphite represented by I) into the isocyanate compound.

The stabilizer used when manufacturing the sole of the present invention can be used when manufacturing any generally known polyurethane, and the stabilizer can be used when the polyisocyanate compound component is, for example, toluene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, etc. Diisocyanate, xylene diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, polymethylene polyphenylisocyanate, 3,3°-dimethyl-4,4”-diphenylmethane diisocyanate, 3,3°-dimethyl-4° 4
'-Biphenylene diisocyanate, 3.3'-dichloro-4,4'-biphenylene diisocyanate, 4.4
It can be used in producing polyurethane using polyisocyanate compounds such as '-biphenylene diisocyanate and 1,5-naphthalene diisocyanate, or mixtures or modified products thereof, or prepolymers thereof. In particular, toluene diisocyanate, 4
, 4°-diphenylmethane diisocyanate, or
Mixtures, modified products, or prepolymers thereof are preferably used in producing polyurethane.

In addition, examples of active hydrogen-containing compounds used in producing the polyurethane used in the sole of the present invention include:
Ethylene glycol, propylene glycol, 1,4-
Low molecular weight polyols such as butanediol, neopentyl glycol, 1.6-hexanediol, glycerin, trimethylolpropane, 1.2.6-hexanediol, pentaerythritol, ethylenediamine, 4.4-hexanediol, etc.
Polyether obtained by adding an alkylene oxide such as ethylene oxide or propylene oxide to an amine compound such as '-methylenebis-2-chloroaniline or 4,4'-methylenebis-2-ethylaniline, or a low-molecular polyol or amine compound. Examples include polyols and polytetramethylene ether glycol,
In addition, ethylene glycol, propylene glycol,
Polyhydric alcohols such as 1,4-butanediol, phthalic acid, maleic acid, malonic acid, succinic acid, adipic acid,
Examples include polyester polyols, polycaprolactone polyols, polycarbonate polyols, acrylic polyols, castor oil, and tall oil, which are polycondensation products with polybasic acids such as terephthalic acid and have hydroxyl groups at the ends. Furthermore, liquid rubbers having active hydrogen groups such as hydroxyl groups, amino groups, imino groups, carboxyl groups, and mercapto groups at the molecular terminals and mixtures thereof can also be used.

When producing the polyurethane used in the soles of the present invention, a reaction catalyst may be added in order to lower the reaction temperature or shorten the reaction time.Specific examples of reaction catalysts include, for example, Examples include amine compounds such as ethylenediamine, tetramethylethylenediamine, and tetramethylhexanediamine and their salts; organometallic compounds such as dibutyltin dilaurate, tin octylate, lead octylate, and manganese octylate; and mixtures thereof. can.

In addition, as auxiliary ingredients, foaming agents such as water and low-boiling organic solvents,
Colorants such as titanium white, calcium carbonate, silica,
Fillers such as clay, organic fibers, and inorganic fibers, softeners such as process oil, foam stabilizers, antistatic agents, and the like may be added as appropriate.

The sole of the present invention can be produced by mixing and stirring, for example, a polyol component containing the ultraviolet absorber and an antioxidant, and an isocyanate component containing a phosphite represented by the formula (I). 45 coated with mold release agent
It is manufactured by pouring into an aluminum shoe sole mold at a temperature of 50°C to 50°C.

[Examples] The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited only to these Examples. Furthermore, in Examples and Comparative Examples, "parts" are all parts by weight.

Examples 1 to 6 Polyester polyol (hydroxyl value 86, average molecular weight 1
300) A predetermined amount of stabilizers other than phosphite esters shown in Examples 1 to 6 in Table 1 were added to 100 parts, and the mixture was heated and stirred at 60 to 80°C for 2 to 6 hours to dissolve. . To this polyol component, 12 parts of ethylene glycol, 0.4 parts of water, 0.8 parts of triethylene diamine, and 1 part of a silicone foam stabilizer were added and mixed, and this was used as a polyol component.

Next, a polyurethane prepolymer (NC0%,
18.5) was added and mixed with a predetermined amount of phosphorous acid ester shown in Examples 1 to 6 in Table 1, and this was used as an isocyanate component.

83 parts of the above polyol component and 10 parts of the isocyanate component
After thoroughly mixing and stirring 0 parts, the mixture was poured into an aluminum shoe sole mold coated with a silicone mold release agent at 45 to 50° C., and taken out after 5 minutes to obtain a shoe sole of the present invention.

After conducting a 30-hour irradiation test on the six types of shoe soles obtained in this way using a carbon arc sunshine weather meter, the degree of yellowing of the test pieces was measured using a colorimeter.
It was indicated by yellow index (Yl value). Results first
Shown in the table.

The test machine used in the experiment is as follows.

(I) Carbon arc weather meter; Suga Test Instruments ■Du Cycle Sunshine Super Long Life Weather Meter WEL-3UN-DC type (2) Embellishing machine; Suga Test Instruments■ SM Color Computer SM-3 Comparative Examples 1 to 11 In Examples 1 to 6, a stabilizer was added during the synthesis of polyurethane, but in Comparative Example 1,
Shoe soles were manufactured using polyurethane to which no stabilizer was added during polyurethane synthesis, and tests similar to those in Examples were conducted.

In Comparative Example 2, a shoe sole was manufactured using a polyurethane synthesized by adding only the ultraviolet absorber used in Examples 1 and 2 as a stabilizer to the polyol component during polyurethane synthesis.

In Comparative Example 3, a shoe sole was manufactured using a polyurethane synthesized by adding only the ultraviolet absorber used in Example 3 to the polyol component as a stabilizer during polyurethane synthesis.

In Comparative Example 4, a shoe sole was manufactured using a polyurethane synthesized by adding only the antioxidant used in Example 1 to the polyol component as a stabilizer during polyurethane synthesis.

In Comparative Example 5, a shoe sole was manufactured using a polyurethane synthesized by adding only the antioxidant used in Example 2 to the polyol component as a stabilizer during polyurethane synthesis.

In Comparative Example 6 and Comparative Example 7, polyurethane synthesized by adding only the phosphorous ester used in Example 1 and Example 2, respectively, as a stabilizer to the isocyanate component was used. Manufactured shoe soles.

In Comparative Example 8, during polyurethane synthesis, Example 1
Shoe soles were manufactured using polyurethane synthesized by adding only the antioxidant and phosphite used in 1 to the polyol component and to the isocyanate component, respectively.

In Comparative Example 9, Example 4 was used during the synthesis of polyurethane.
The antioxidant used in Example 4 was added to the polyol component, and the phosphite ester phenyl diisodecyl phosphite used in Example 4 was added to the isocyanate component to produce a shoe sole using the synthesized polyurethane.

In Comparative Example 10, during the synthesis of polyurethane, the ultraviolet absorber used in Example 1 was added to the polyol component, and the phosphorous ester had a phosphorus content of 3.
．． Shoe soles were manufactured using polyurethane synthesized by adding 8% by weight of trioleyl phosphite to an isocyanate component.

In Comparative Example 11, during the synthesis of polyurethane, the ultraviolet absorber used in Example 1 was added to the polyol component, and N, a phenylenediamine compound, was added instead of the phosphite.

A shoe sole was manufactured using a polyurethane synthesized by adding N'-diphenyl-p-phenylenediamine to an isocyanate component.

The specific means for producing soles in Comparative Examples 1 to 11 above are all the same as in the Examples except for the operation related to adding the stabilizer.

Table 2 shows the results of tests conducted on the soles manufactured in Comparative Examples 1 to 11 in the same manner as in the Examples.

〔Effect of the invention〕

As specifically shown in the detailed description of the invention and the examples, the sole of the present invention has excellent performance that conventional shoe soles do not have in terms of its white color retention. It is.

That is, the soles manufactured according to the present invention do not cause discoloration or discoloration, even if they use toluene diisocyanate or 4,4'-diphenylmethane diisocyanate, which are easily colored, as the isocyanate component of the polyurethane raw material.
It has the property of being resistant to peeling, something that could not be achieved with polyurethanes using previously known stabilizers. The sole of the present invention makes it possible to maintain its commercial value at an extremely high level.

Claims (1)

[Claims] 1. (a) Ultraviolet absorber (b) Antioxidant, and (c) General formula (I) ▲There are numerical formulas, chemical formulas, tables, etc.▼(I) (R_1, R_2, R_3 are (representing the same or different alkyl group, cycloalkyl group, aryl group, alkylaryl group, or aralkyl group) and whose phosphorus content is in the range of 4.0 to 14.0% by weight. 2. The shoe sole according to claim 1, wherein the shoe sole 2 is made of polyurethane resin, and the ultraviolet absorber is a benzotriazole ultraviolet absorber. 3. The sole according to claim 1, wherein the antioxidant is a hindered phenol compound having at least one branched lower aliphatic hydrocarbon group bonded to the ortho position. The phosphite ester is 6
．． The shoe sole according to claim 1, which has a phosphorus content of 0 to 8.0% by weight.