JPH0716444B2 - Molding method for shoe soles with different color protrusions - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a shoe sole having different color protrusions.

[0002]

2. Description of the Related Art Conventionally, a lower mold having a projection-forming concave portion and a primary upper mold (dammy mold) according to Japanese Patent Laid-Open No. 1-238804.
The injection of liquid polyurethane into the projection forming void formed by the injection molding and injection molding of the projection, and then the primary upper mold is replaced with the secondary upper mold (last mold with the scabbard suspended). Forming a bottom body molding void, introducing a foamable liquid polyurethane of a different color from the protrusions into this shoe sole molding void,
There has been proposed a method for molding a shoe sole body by foaming and curing the same and forming a shoe sole having a different-colored protrusion for laminating the shoe sole body and the protrusion.

However, since the projections are molded by injection molding, it is necessary to provide a runner or a gate on the molding die, which requires a precise lower die, an upper die and an injection molding apparatus, and the molding apparatus is large. However, it is not suitable for molding a large number of shoes in small quantities.

[0004]

SUMMARY OF THE INVENTION The present invention is intended to provide a small amount of various kinds of shoe soles having different color protrusions at a low cost by a simple method.

[0005]

The present invention will be described below with reference to the drawings showing an embodiment of the present invention. In the present invention, a lower mold 1 having a flat bottom surface 11 provided with projection forming concave portions 111.111 ...
, A step of introducing a liquid polyurethane a having a volume equal to or larger than that of the projection forming recesses 111.111 ... by a casting method, and the lower surface 21 is covered with the recesses 111.111 ... of the lower mold 1 and the outer periphery 112.112 of the recesses. The primary upper mold 2 having the projections 211.211 ...
The liquid polyurethane a injected into the lower mold 1 by 11 is press-fitted into the protrusion molding concave portions 111.111 ... of the lower mold to mold the protrusions 5.5.
The upper mold protrusions 211.211 ...
The protrusions are protruded to 2.212 ... to form burrs 6.6 ..., and the projections 5.5 ... and the burrs 6.6 ... Are cut at the outer peripheral edges 51.51 ... And Bali 6.
6 ... Semi-curing, removing the primary upper mold 2 from the lower mold 1 and scraping and removing the burr 6.6 held on the bottom surface 11 of the lower mold, and holding the protrusions 5.5. Lower mold 1
Introducing a foamable liquid polyurethane b of a different color from the projection 5.5 ... by a casting method, fitting the secondary upper mold 3 to the lower mold 1 and fitting the secondary upper mold 3 to the upper surface of the projection 5.5. The present invention is directed to a method of molding a shoe sole having different-colored projections, which is characterized in that the shoe bottom body 7 and the projections 5.5 are laminated and integrated by forming 7 and foaming and hardening them. .

In the present invention, the liquid polyurethane a for molding the protrusions and the foamable liquid polyurethane b for molding the sole body 7 are general-purpose polyether type polyols, polyester type polyols or derivatives thereof. A compound obtained by reacting an amine-based polyol with a known isocyanate compound is used.

In the present invention, the projection forming recess 111.1
11 may be independent of each other, or may be continuously formed in a mesh shape or a cobweb shape. In the present invention, the liquid polyurethane a for molding the protrusion may be solid or foamable. For example, depending on the application,
When high hardness is required, such as shoe, golf shoe, and baseball shoe soles, solid liquid polyurethane is used.

In the present invention, the burr 6.6 can be easily scraped and removed by using a spatula c or the like.

In the present invention, the shoe sole body 7 is formed by molding the surface 51.51 of the projections 5.5 held by the lower mold 1.
That is, it is desirable to perform it before the adhesion surface with the shoe sole body 7 becomes tack-free (before the hardening progresses and the tackiness of the surface is lost). Surface of protrusion 52.
If 52 is completely tack-free, there is a fear that the adhesiveness between the molded sole body 7 and the projection 5.5 may deteriorate. Especially, when the hardness difference between the projections 5.5 and the shoe sole body 7 is large, this defect is remarkable.

[0010]

As described above, according to the present invention, the liquid polyurethane a is introduced into the lower mold 1 by the casting method, and the primary upper mold 2 is fitted into the lower mold 1 and pressurized, whereby the liquid polyurethane a is removed. It is possible to press fit and fill all over the projection forming recesses 11.111 ... of the lower mold, and the surplus liquid polyurethane a is made to protrude into the voids 212.212 of the upper mold to form burrs 6.6.
..., the liquid polyurethane a does not become insufficiently filled in the projection forming concave portions 111.111, and the burr 6.6 ... Is the outer peripheral edge 51.5 of the upper mold projection.
Since they are simultaneously cut and cut by 1 ..., if the primary upper mold 2 is detached from the lower mold 1 after the projection 5.5 is molded, the burrs 6.6 ... Attached to the flat bottom surface 11 of the lower mold The shoe sole body 7 can be cast-molded on the upper surfaces of the protrusions 5.5 ... Therefore, unlike the conventional case, it is not necessary to use a precise lower mold or upper mold injection device for molding a shoe sole having a different-colored projection by an injection molding method, and a small amount of various kinds of shoe soles can be molded and provided at low cost.

[Brief description of drawings]

FIG. 1A. It is an important section sectional view showing a projection formation state.
B. It is a principal part sectional view which shows a shoe sole main body molded state.

FIG. 2 is a cross-sectional view of essential parts showing a state where liquid polyurethane is introduced into a lower mold by a casting method.

FIG. 3 is a cross-sectional view of essential parts showing a state in which burrs are scraped off and removed.

[Explanation of symbols]

1. Lower mold 11 ... Bottom surface 111 ... Protrusion molding concave portion 112 ... Outside of concave portion 1. Primary upper mold 21 ... Lower surface 211. Protrusion 212. Void 3. Secondary upper mold 4. Molding space for shoe sole body 5. Protrusion 51. Outer rim 6. Bali 7. Sole body a. Liquid polyurethane b. Foamable liquid polyurethane c. Spatula

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Claims (1)

[Claims] 1. A flat bottom surface 11 having a projection forming recess 111.
In the lower mold 1 provided with 111 ...
1. A step of introducing a liquid polyurethane a having a volume of 1 or more by a casting method, and a recess 111.1 of the lower mold 1 on the lower surface 21.
11 and the primary upper mold 2 having the projections 211.211 covering the outer periphery 112.112 of the recess are fitted into the lower mold 1, and the liquid injected into the lower mold 1 by the projections 211.211. Polyurethane a is used as the lower mold projection recess 11
1.11 ... is press-fitted to form protrusions 5.5 ...
Excess liquid polyurethane a
The protrusions 5.5 and the burrs 6.6 are cut off along the outer peripheral edge 51.51 of the protrusions while protruding into the voids 212.212 formed between. After that, the step of semi-curing the protrusions 5.5 and the burrs 6.6, and the bottom 11 of the lower mold by separating the primary upper mold 2 from the lower mold 1
A step of scraping and removing the burr 6.6 ...
A foamable liquid polyurethane b having a different color from that of the protrusions 5.5 is introduced into the lower mold 1 holding the protrusions 5.5 by a casting method, and the secondary upper mold 3 is fitted to the lower mold 1. The sole body 7 is formed on the upper surfaces of the protrusions 5.5, and the sole body 7 and the protrusions 5.5 are laminated and integrated by foaming and hardening the sole body 7, and Molding method.