EP2425733A1

EP2425733A1 - Method for manufacturing a shoe and shoe component used in the method

Info

Publication number: EP2425733A1
Application number: EP10425286A
Authority: EP
Inventors: Simone Donati
Original assignee: Versilia Calzature Srl
Current assignee: Versilia Calzature Srl
Priority date: 2010-09-03
Filing date: 2010-09-03
Publication date: 2012-03-07

Abstract

A method for the manufacture of a shoe, which consists in applying a multilayer structural insole (1) to the sole of a forming body; in assembling an upper (4) to the multilayer structural insole (1), after juxtaposing it to the forming body, by adhesive bonding thereto, obtaining a lasted shoe; in closing the upper (4) onto the heel, a step known in the technical jargon of the field as seating; in abrading the lower part of the upper (4) in order to level its surface; in depositing an adapted adhesive on the lower part of the lasted shoe and onto the upper end face of a sole, juxtaposing them and subjecting them to a mutual compression pressure; in extracting the forming body from the inside of the shoe obtained earlier; in extracting at least one layer (2) of the multilayer structural insole (1), leaving inside the shoe at least one additional layer (3) provided with an adhesive surface; and in superimposing a contoured flap (5) on the at least one layer (3) provided with an adhesive surface that is present within the shoe with consequent mutual adhesive bonding.

The present invention further relates to a component (1) constituted by a multilayer structural insole (1) provided with at least one layer made of a material of the type of cardboard (2), at least one layer made of a material of the type of hide (3), having respective complementary surfaces which are associated detachably, by means of at least one layer constituted by an adhesive substance, which is arranged on the surface of the layer made of a material of the type of hide (3) that faces the layer made of a material of the type of cardboard (2).

Description

The present invention relates to a method for manufacturing a shoe and to a corresponding component for shoes used in such method.
Various methods for manufacturing shoes are known which have some particular complexities in execution and some substantially insurmountable limits in application. The main methods currently in use are described hereafter.
The most widespread way of manufacturing a shoe, which is generally known as lasting in the jargon of the field, provides for a production process that entails the adoption of different components: a forming body (a substantially rigid element that reproduces the form of the foot and is necessary to give the correct shape to the shoe), an assembly insole (generally made of rigid cardboard), an upper, an actual sole, a footbed (also known as hygienic insole).
This first production method provides for the following steps: first of all it is necessary to apply the assembly insole to the sole of the forming body and then one proceeds with the assembly of the upper on the forming body and finally with its adhesive bonding to the assembly insole, obtaining what is called the lasted shoe. At this point the following are necessary: closure of the upper on the heel (a step known in the jargon of the field as seating) and the abrasion of the lower part of the upper, which is necessary in order to level any thicknesses that might cause difficulty in the application of the sole and in creating a suitable surface for applying the adhesive.
At this point it is possible to spread the adhesive on the lower part of the lasted shoe and onto the upper end face of the sole, with their subsequent coupling and mutual pressing.
The shoe is then completed by extraction of the forming body and gluing of the footbed inside the shoe. Any finishing operations to eliminate residues of processing that are still present on the finished shoe can then be performed.
As an alternative, it is possible to resort to so-called "sack" manufacture, in which the following components are used: a forming body, an assembly insole made of soft material, an upper (which is perfectly complementary to the contour of the forming body and is made of a material that does not yield upon assembly), a sole and a footbed.
This second manufacturing method provides for the following steps: assembly of the inside-out upper to the assembly insole by means of an adapted stitched seam, followed by the turning inside out of the sewn assembly of the upper and the insole and arranging them in the correct position. It is thus necessary to insert the forming body in the preassembled shoe, and this is followed by the abrasion of the lower part of the upper (a step that has the same purposes as the equivalent step of the first method described), with consequent deposition of the adhesive onto the lower part of the shoe and onto the upper end face of the sole. Their subsequent joining and mutual pressing will ensure assembly. It is therefore possible to proceed with the extraction of the forming body from inside the shoe and with the gluing of the footbed, thus obtaining the finished shoe. In a manner similar to what has been described for the previous process, it is then possible to perform additional finishing operations to eliminate work residues that are still present on the finished shoe.
A third possible embodiment is known as "hand-sewn inside-out work". It derives from a production process that entails the assembly of the following components: a forming body, an upper (which also in this case has a shape and dimensions which are complementary to those of the forming body), a sole and a footbed.
This third embodiment is developed in the following steps: assembly by hand sewing of the inside-out upper to the sole, which must be thicker than in shoes obtained with the other methods in order to withstand the direct sewing of the upper onto it, turning inside out the assembly constituted by the upper and the sole, moving it into the correct position; insertion of the forming body in the preassembled shoe; passing of the shoe into ovens so that the upper assumes the preset shape; extraction of the forming body from the inside of the shoe; application of the heel to the sole by means of nails; gluing of the footbed inside the shoe, thus obtaining the finished shoe. Any further finishing operations are not excluded in this case either.
The lasted manufacture type is the simplest and the one with the lowest production cost, since it is possible to adapt the uppers to a plurality of different forming bodies.
However, the finished product obtained with this first type of manufacture is qualitatively inferior to the one that can be obtained with "sack" manufacturing or with the manufacturing known as "hand sewn".
The need to have available an extremely precise upper for sack manufacturing and for hand sewn manufacturing further entails a care and precision of its sewing/fixing which causes a substantial increase in production times and in the corresponding costs.
The aim of the present invention is to solve the above-mentioned drawbacks, by providing a method for manufacturing a shoe that is particularly quick and has low costs.
Within this aim, an object of the invention is propose a method for providing a shoe that is suitable for the production of shoes which are comfortable and of high quality with the smallest expenditure of time and cost.
Another object of the invention is to propose a component for shoes that is used in such method and is particularly versatile and adapted to mate stably and precisely with a plurality of different uppers even though they are not specifically dedicated to it.
A further object of the present invention is to provide a method for manufacturing a shoe and a shoe component used in such method which have low costs, are relatively simple to provide in practice and safe in application.
This aim and these objects, as well as others that will become better apparent hereinafter, are achieved by means of a method for the manufacture of a shoe, which comprises the steps of:

a) applying a multilayer structural insole on the sole of a forming body;
b) assembling an upper to the multilayer structural insole, after juxtaposing it to the forming body, by adhesive bonding thereto, obtaining a lasted shoe;
c) closing the upper onto the heel, a step known in the technical jargon of the field as seating;
d) abrading the lower part of the upper in order to level its surface;
e) depositing an adapted adhesive on the lower part of the lasted shoe and onto the upper end face of a sole, juxtaposing them and subjecting them to a mutual compression pressure;
f) extracting the forming body from the inside of the shoe obtained in step e);
g) extracting at least one layer of the multilayer structural insole, leaving inside the shoe at least one additional layer provided with an adhesive surface;
h) superimposing a contoured flap on the at least one layer provided with an adhesive surface that is present within the shoe with consequent mutual adhesive bonding.

This aim and these objects are further achieved by a component for shoes used in said method, characterized in that it comprises a multilayer structural insole provided with at least one layer made of a material such as cardboard, at least one layer made of a material such as hide, having respective complementary surfaces which are mutually associated detachably, by means of at least one layer constituted by an adhesive substance, which is arranged on the surface of the layer made of a material such as hide which faces the layer made of a material such as cardboard.
Further characteristics and advantages of the invention will become better apparent from the detailed description that follows of a preferred but not exclusive embodiment of the method for manufacturing a shoe and of the component for shoes used in such method according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a partially exploded perspective view of a component for shoes used in the method according to the invention;
Figure 2 is a partially exploded perspective view of an enlarged-scale detail of a component for shoes used in the method according to the invention;
Figure 3 is a perspective view of the initial steps of the method according to the invention;
Figure 4 is a perspective view of the first intermediate steps of the method according to the invention;
Figure 5 is a perspective view of the second intermediate steps of the method according to the invention;
Figure 6 is a perspective view of the final steps of the method according to the invention.

With reference to the figures, the reference numeral 1 generally designates a component for shoes used in the method for manufacturing a shoe according to the invention.
The method consists of a sequence of consecutive steps.
Initially, during a first step a), it is necessary to apply a multilayer structural insole 1 on the sole of a forming body (which is not shown in the accompanying figures to allow them to be more intuitive).
The forming body is a structure which is generally solid and in any case rigid, is mostly made of polymeric material and reproduces the contour of the foot, around which the shoe is contoured and manufactured.
The adoption of the multilayer structural insole 1 is the main distinctive characteristic of the method according to the invention; it is indeed thanks to the insole 1 that the method occurs in practice, making the sequence of steps that compose it simple and effective.
In more general terms, the insole 1 (or component 1 for shoes) is provided with at least one layer of a material of the type of cardboard 2, at least one layer of a material of the type of hide 3, which have respective complementary surfaces which are mutually associated detachably, by means of at least one layer constituted by an adhesive substance, arranged on the surface of the layer made of a material such as hide 3 that faces the layer made of a material such as cardboard 2. The particular characteristics of each layer and of the entire insole 1 will be highlighted at best hereinafter in the description.
During a second step b) it is necessary to assemble an upper 4 to the multilayer structural insole 1 after juxtaposing it to the forming body, by adhesive bonding thereto, obtaining a lasted shoe.
It is then necessary, during a third step c), to close the upper 4 on the heel, a step which is known in the technical jargon of the field as seating.
It is then necessary to perform an abrasion (step d)) of the lower part of the upper 4 in order to level its surface.
By means of the deposition (step e)) of an adapted adhesive on the lower part of the lasted shoe and on the upper end face of a respective sole (by juxtaposition and by submitting them to a mutual compression pressure), a blank is obtained whose appearance is similar to that of the finished shoe.
In a subsequent step f) it is necessary to extract the forming body from the inside of the shoe obtained in step e) and, in an additional step g), to extract at least one layer 2 of the multilayer structural insole 1, leaving inside the shoe at least one additional layer 3 provided with an adhesive surface.
The method is concluded with a step h) in which it is necessary to superimpose a contoured flap 5 on the at least one layer 3 provided with an adhesive surface that is present within the shoe with consequent mutual adhesive bonding.
In order to optimize the method and make it particularly efficient and simple to execute, it is convenient to use, as a contoured flap 5 of step h), a contoured portion 6 made of soft material (for example sponge rubber or other expanded material or cork or optionally elastomers and/or elastomeric foams) coupled to a sheet 7 whose shape is complementary to the shape of the portion 6.
The sheet 7 is preferably made of hide and/or materials that have similar characteristics and properties.
An adapted stratification of adhesive material is advantageously deposited between the sheet 7 and the portion 6 so as to ensure the stability of their coupling.
It is appropriate to note that from a production standpoint it will be often necessary to perform, at the end of said step h) of assembly of the contoured flap 5, an additional step i), during which the shoe can be finished by elimination of imperfections, any threads and other portions that protrude and the like.
It is convenient to stress that the execution of the abrasion step d) entails the surface abrasion of the protruding edge of the upper 4 so as to create a suitable surface for the laying and stable cohesion of the adhesive and to level any irregular thicknesses that would make the subsequent application of the sole (step e)) difficult.
During the step b) of assembly of the upper 4 to the multilayer structural insole 1 it is fundamental to point out that the upper 4 to be used must fulfill the only requirement of having dimensions that are not smaller than the ideal coupling dimensions. -
In practice, therefore, regardless of the forming body in use, the upper 4 must have dimensions that are optionally even much larger than the ones that are complementary to such forming body, and this dimensional difference (abundance) will not affect in any way the stability and precision of the assembly and of the subsequent steps of the method.
As regards the insole 1, it is convenient to note that between the layer made of a material of the type of cardboard 2 and the layer made of a material of the type of hide 3, firmly coupled to the layer made of a material of the type of cardboard 2, it comprises a removable laminar layer 8 which adheres to the adhesive substance.
The laminar layer 8 is constituted by a sheet which is provided with a first face (the one that lies opposite the one that is jointly connected to the layer made of a material of the type of cardboard 2) on which a material is distributed which is adapted to prevent permanent adhesive bonding of the adhesive substance.
It is convenient to note that the sheet is preferably made of a material of the type of paper.
It is equally interesting from the point of view of application that the material adapted to prevent permanent adhesive bonding of the adhesive substance is preferably selected among a silicone, a silicone derivative and a compound containing silicone.
In practice, according to a possible embodiment of unquestionable interest in practice and in application, the removable laminar layer 8 is constituted by a sheet of paper which is provided with a face on which a thin lamina of silicone acting as a release agent is deposited.
It is very important to point out that the layer of material of the type of hide 3 is provided by means of materials selected among regenerated hide, regenerated leather, leather in any form thereof and hide in any form thereof.
Among the various types of regenerated hide, mention is made of the material known commercially as "salpa" as being particularly interesting and indicated for application in the method according to the invention and for the provision of the component 1 (insole 1 ) according to the invention.
This material comprises trimmings and shavings of tanned hides and defibered hides in quantities equal to 60-65%, rubber in quantities equal to 15-18%, synthetic tanning agents in quantities equal to 4-5% and other additives; such material has as an indicative specific gravity of 820-900 g per square meter if provided with a thickness of 1 mm.
The process and product innovation provided by means of the invention generates unquestionable advantages in terms of design, production and sale.
Design is in fact simpler and less expensive, since the shoe is created by using as a base the process previously termed lasting, with the advantages that it entails in terms of simplicity and versatility. In this manner, it is in fact possible to create models of uppers 4 that can be adapted to different types of forming bodies. This is not possible in "sack" and "hand sewn" work, since both require each forming body to have its own model created to size, without any interchangeability.
Accordingly, the department assigned to the creation of the models reduces production costs.
If the modeler in fact wished to create a flexible and comfortable shoe (such as the one obtained by the "sack" or "hand sewn" processes), he would have to create many more models (each different forming body requires its own model).
Instead, by adopting the method and the component 1 (insole 1 ) according to the invention the modeler can use the same model for many different forming bodies.
Moreover, with "sack" or "hand sewn" work, each model requires its own development and meticulous fine-tuning for subsequent entry into production, operations which, when the method according to the invention and the corresponding component 1 are adopted, are fare more approximate and therefore cheaper.
This has positive repercussions also in production, by streamlining it, reducing considerably the number of models, developments and cutouts (contours provided by means of steel blades that duplicate the shapes of the models to blank the raw materials for the upper 4) with respect to the number of forming bodies and consequently the cost of raw materials.
Operators assigned to the application of the method according to the invention do not have to perform hand stitches in order to mount the upper 4 to the sole: therefore, there is no need for this additional handicraft skill, which is instead necessary for the application of known types of methods.
The production step utilizes the advantages caused by the design step. The cutting of the upper 4 does not require particular precision (creation of shapes and dimensions that are complementary to those of the forming body).
It is further very important to stress that in terms of provision of the shoe, the stitched seam that joins the upper 4 to the assembly insole (which is instead present in "sack" manufacturing) is eliminated, and that the hand sewing of the upper 4 onto the sole (provided in "hand sewn" manufacture) is not envisaged.
The insertion of the insole 1 is easy, quick and scarcely onerous, since its cost is equal to that of an ordinary assembly insole, and generates waste that can be recycled to 100% in compliance with sorted collection, since it is made of paper-like material. Moreover, the consumption of adhesives is reduced, since they are not necessary for the adhesive bonding of the contoured flap 5.
The resulting final product is a soft and comfortable shoe. This is determined exclusively by the insole 1, which once deprived of the layer 2 (leaving the layer 3 preferably constituted by the material known as salpa on which the adhesive is distributed) allows direct application of the contoured flap 5, ensuring that the thickness "lost" through the elimination of the cardboard (which constitutes the layer 2) is recovered, adding softness and giving the shoe unique characteristics of comfort and flexibility (due to the presence of the contoured portion 6). In addition to qualitative improvements of the product, it is also economically competitive; its production cost is in fact distinctly lower than that of "sack" or "hand sewn" processes, since there is a smaller incidence of the cost of raw materials and in particular of the workforce used: saving of the latter is approximately 50% of the cost on an hourly basis and does not require specialized personnel in all the steps of production.
Advantageously, the method for providing a shoe according to the invention is particularly quick and has low costs.
Conveniently, the method for providing a shoe is suitable for the production of shoes that are comfortable and of high quality with minimum expenditure of cost and time.
Positively, the multilayer insole 1 (component 1 ) is particularly versatile and adapted to mate stably and with precision with a plurality of different uppers 4, even if they are not precisely dedicated thereto.
The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims; all the details may further be replaced with other technically equivalent elements.
In the exemplary embodiments shown, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other exemplary embodiments.
Moreover, it is noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject of a disclaimer.
In practice, the materials used, as well as the dimensions, may be any according to requirements and to the state of the art.
Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

A method for the manufacture of a shoe, which comprises the steps of:
a) applying a multilayer structural insole (1) on the sole of a forming body;

b) assembling an upper (4) to the multilayer structural insole (1), after juxtaposing it to the forming body, by adhesive bonding thereto, obtaining a lasted shoe;

c) closing the upper (4) onto the heel, a step known in the technical jargon of the field as seating;

d) abrading the lower part of the upper (4) in order to level its surface;

e) depositing an adapted adhesive on the lower part of the lasted shoe and onto the upper end face of a sole, juxtaposing them and subjecting them to a mutual compression pressure;

f) extracting the forming body from the inside of the shoe obtained in step e);

g) extracting at least one layer (2) of the multilayer structural insole (1), leaving inside the shoe at least one additional layer (3) provided with an adhesive surface;

h) superimposing a contoured flap (5) on the at least one layer (3) provided with an adhesive surface that is present within the shoe with consequent mutual adhesive bonding.
The method according to claim 1, which consists in adopting, as a contoured flap (5) of step h), a contoured portion (6) made of soft material, which is coupled to a sheet (7) shaped complementary to the portion (6), between said sheet (7) and said portion (6) there being an adapted layering of adhesive material to ensure stability of the coupling.
The method according to claim 1, which consists in
i) finishing said shoe, eliminating imperfections, any threads and other protruding portions and the like.
The method according to claim 1, which consists in performing said abrasion step d) by abrading superficially the protruding edge of said upper (4), creating an adapted surface for the laying and stable cohesion of the adhesive and leveling any irregular thicknesses that would make the application of the sole difficult.
The method according to claim 1, which consists in adopting, in step b) for the assembly of the upper (4) to the multilayer structural insole (1), an upper (4) whose dimensions are not smaller than the ideal coupling dimensions regardless of the forming body being used, dimensions possibly even far larger not affecting the stability and precision of the assembly and of the subsequent steps of the method.
The component for shoes used in the method according to claim 1, characterized in that it comprises a multilayer structural insole (1), which is provided with at least one layer made of a material of the type of cardboard (2), at least one layer made a material of the type of hide (3), having respective complementary surfaces which are mutually associated detachably, by means of at least one layer constituted by an adhesive substance, arranged on the surface of the layer made of a material of the type of hide (3) that faces the layer made of a material of the type of cardboard (2).
The component according to claim 6, characterized in that between said layer made of a material of the type of cardboard (2) and said layer made a material of the type of hide (3), firmly coupled to said layer made of a material of the type of cardboard (2), it comprises a removable laminar layer (8), which adheres to said adhesive substance and is constituted by a sheet provided with a first face on which a material is distributed which is adapted to prevent permanent adhesive bonding of the adhesive substance and a second face that is stably coupled to said layer made of a material of the type of cardboard (2).
The component according to claim 6, characterized in that said sheet is made of a material of the type of paper.
The component according to claim 6, characterized in that said material adapted to prevent permanent adhesive bonding of the adhesive substance is selected among a silicone, a silicone derivative and a compound containing a silicone.
The component according to claim 6, characterized in that said layer made of a material of the type of hide (3) is made of materials selected among regenerated hide, regenerated leather, leather in any form thereof and hide in any form thereof.