Classifications

• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B17/00—Insoles for insertion, e.g. footbeds or inlays, for attachment to the shoe after the upper has been joined
  • A43B17/04—Insoles for insertion, e.g. footbeds or inlays, for attachment to the shoe after the upper has been joined with metal insertions or coverings
• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B7/00—Footwear with health or hygienic arrangements
  • A43B7/36—Footwear with health or hygienic arrangements with earthing or grounding means

Definitions

• the present invention relates to a shoe insole for eliminating static electricity, which comprises ferroelectric elements inserted therein, and thus can eliminate static electricity, and more particularly to aninsole for eliminating static electricity, which has the same external structure as that of general shoe insoles and can be applied to all kinds of shoes so as to efficiently eliminate static electricity generatedin the human body.
• the present invention relates to an insole for eliminating static electricity, which comprises PZN-based ferroelectric elements included therein, and thus can eliminate static electricity generated in the human body.
• shoesfor eliminating static electricity which function to eliminate static electricity generated in the human body, are mostly manufactured by adding a metal such as silver, copper or aluminum, or a conductive material such as conductive carbon, to a shoe insole made mainly of ethylene vinyl acetate (EVA).
• EVA ethylene vinyl acetate
• Such an insole for eliminating static electricity is technology of dissipating static electricity using a method of allowing electric charges generated in the human body to be naturally discharged through ethylene vinyl acetate (EVA) foam.
• This method allows static electricity to be eliminated to some extent, but when such a static electricity- eliminating insole is used to eliminate static electricity, there are problems in that it is difficult to efficiently eliminate static electricity due to a shoe midsole having insulating properties, and the risk of receiving an electric shock due to conductive phenomena can occur.
• Korean Utility Model Laid- open Publication No. 98-6316 published on 30 April, 1998) and Korean Utility Model Registration Nos. 274092 (registered on 20 April, 2002), 320706 (registered on 8 July, 2003) and 424809 (registered on 21 August, 2006) disclose improvements in shoes for eliminating static electricity.
• Suchshoes have a structure as shown in FIG. 1, in which a grounding element 4 for discharging static electricity is included in the shoes, such that it comes into contact with a foot sole and a ground surface E, and thus electric charges generated in the human body can be discharged to the ground surface E through an insole 1, a miodsole 2 and an outsole 3.
• the present invention has been solved in order to solve the above-described problems occurring in the prior art, and it is an object of the present invention to provide an insole for eliminating static electricity, which is a simple structure having the same appearance as a conventional shoe insole, as shown in FIG. 2, and can be applied to all kinds of shoes so as to efficiently eliminate static electricity generated in the human body.
• the insole for eliminating static electricity according to the present invention has a simple external structure, which can be simply used in all kinds of shoes, including not only general shoes, but also safety shoes for wearing in various industrial fields, and it can efficiently eliminate static electricity generated in the human body.
• the insole according to the present invention is characterized in that it can prevent not only various accidents, such as firing explosion and a fire, which occur due to the generation of static electricity in industrial fields, but also various safety accidents, such as electricshocks, body injuries, and unpleasant sensations by electric discharge sound, which occur due to the generation of static electricity in daily life.
• the present invention provides an insole having characteristics which will now be described in detail.
• the external structure of the inventive insole for eliminating static electricity has the same shape as conventional shoe insole, as shown in FIG. 2, such that the inventive insole can be simply used in not only general shoes, but also safety shoes for wearing in various industrial fields.
• the inventive insole for eliminating static electricity comprises: a top layer made of conductive synthetic resin; a middle layer made of antistatic soft foam; and a bottom layer made of antistatic hard synthetic resin, wherein a pair of ferroelectric elements and an electric discharge net are inserted between the soft foam middle layer and the hard synthetic resin bottom layer.
• the top layer is a conductive synthetic fabric woven from synthetic resin yarns having silver yarns arranged thereon at a given interval and serves as a conducting material to conduct electric charges,generated in the human body, directly to the soft foam middle layer by means of the silver yarns. Also, because the silver yarns have excellent antibacterialand deodorant effects, the top layer also has an additional function to inhibit bacterial proliferation and the generation of offensive odors, which occur due to sweat released from a foot sole.
• the soft foam middle layer functions to conduct electric charges from the top layer, made of the conductive synthetic fabric woven using synthetic resin yarns and silver yarns, to the ferroelectric elements and the electric discharge net, which are inserted between the middle layer and the bottom.
• the soft foam middle layer is made of antistatic soft foam and also functions as a cushion layer, which prevents the unpleasant sensations of the ferroelectric elements and the electric discharge net, which are inserted between the soft foam middle layer and the hard synthetic bottom layer, from being transferred to a foot sole.
• the soft foam middle layer is made of a soft foam material, which is obtained by foaming a mixture of ethylene vinyl acetate (EVA), conductive carbon and a foaming agent, such that shock absorption in the foaming process is increased.
• the soft foam material is preferably prepared by adding additives, including a foaming agent, zinc oxide and stearate, to a mixed base of 70-90 wt% of ethylene vinyl acetate (EVA) and 10-30 wt% of conductive carbon, and foaming the mixture, such that the soft foam material has antistatic performance.
• the mechanical properties of the shoe insole can be reduced as a result of the reduction in the amount of addition of ethylene vinyl acetate (EVA), which is excellent in mechanical properties, including elasticity, elongation and tensile strength.
• EVA ethylene vinyl acetate
• the amount of ethylene vinyl acetate (EVA) added is more than 90 wt% or the amountof conductive carbon added is less than 10 wt%, electric charges generated in the human body cannot be smoothly conducted to the ferroelectric elements, such that static electricity generated in the human body cannot be smoothly eliminated, because the amount of conductive carbon added is relatively small compared to the amount of ethylene vinyl acetate (EVA) added.
• the foaming agent functions to expand ethylene vinyl acetate (EVA) to increase the impact resistance of the EVA. If the amount of foaming agent added is lower than the lower limit of the above- specified range, ethylene vinyl acetate (EVA) cannot be sufficiently foamed, and if it exceeds the upper limit of the above-specified range, ethylene vinyl acetate (EVA) can be excessively foamed, resulting in a reduction in the mechanical properties thereof.
• EVA ethylene vinyl acetate
• a foaming agent usable in the present invention is a conventional foaming agent, and is preferably an azodicarbonamide foaming agent.
• azodi- carbonamide has a relatively high decomposition temperature of 210 0 C it is required to add a decomposition promoter in order to lower the decomposition temperature of the azodicarbonamide foaming agent.
• zinc oxide is used as an active agent for lowering the decomposition temperature of azodicarbonamide, and when it is used in an amount within the above- specified range, it can lower the undesired high decompos ition- temperature of azodicarbonamide.
• stearate which is used in the present invention, is added in an amount within the above- specified range and is suitably coated with the foam material.
• Stearate which can be used in the present invention, is preferably one selected from the group consisting of zinc stearate, calcium stearate, magnesium stearate and aluminum stearate.
• the ferroelectric elements which are used in the present invention, are piezoelectric elements and function to receive electric charges from the soft foam middle layer, andthen to discharge the electric charges to the hard synthetic resin bottom layer, thus eliminating the electric charges.
• the ferroelectric elements are key parts, which function to absorb and neutralize positive (+) or negative (-) electric charges in positive (+) or negative (-) electrodes to dissipate electric charges, and the ferroelectric elements are subjected to poling treatment, such that they have positive (+) and negative (-) polarities, respectively.
• PZN-BT-PT ferroelectric element BT-PT[Pb(Zn Nb )O J-BT[BaTiO ]-PT[PbTiO ] ferroelectric elements
• the PZN-BT-PT ferroelectric element preferably has a relative dielectric constant of 3,000-6,000. If the PZN-BT-PT ferroelectric elements have a relative dielectric constant of less than 3,000, static electricity generated in the human body will not be rapidly conducted to the antistatic hard synthetic bottom layer, such that electric potential enough to stimulate the human body will remain in the insole so as to give electrostatic stimulation to the human body. On the other hand, the PZN-BT-PT ferroelectric elements have a relative dielectric constant of more than 6,000, it will be difficult to fabricate and can be readily damaged.
• the PZN-BT-PT ferroelectric element 20, which is used in the present invention is preferably made of a mixture of 0.55-0.65 mol PZN[Pb(Zn Nb )O 1, r J 1/3 2/3 3
• the ferroelectric element is inserted between the middle layer and the bottom layer, it is included in a [H] -shaped groove formed in a convex arch portion protruding from the middle of the bottom, such that it can readily come into contact with a foot sole and the middle layer, whereby electric charges generated in the human body are discharged.
• arch portion (A) refers to the convex arch-shaped portion of the insole, which can support the concave arch portion (indicated by a dotted line in FIG. 3) of the human foot sole.
• the electric discharge net is made of a conductive foam material having a horseshoe-shaped network structure, and is included in a [H] -shaped groove formed in the shoe heel portion of the hard synthetic resin bottom layer, such that it can come into contact with the middle layer.
• the electric discharge net is made of the same material as the material of the soft foam middle layer, and the detailed description of said material has been already made, and thus will be omitted herein.
• the hard synthetic resin bottom layer in the present invention is a layer for dissipating the electric charges charged in the ferroelectric elements and the electric charges discharged through the electric discharge net. It is made of a mixture of hard ethylene vinyl acetate (EVA) and conductive carbon and functions to relieve local pressure applied externally from a road surface through the outsole and midsole when a person walks.
• EVA hard ethylene vinyl acetate
• the hard synthetic resin bottom layer consists of an antistatic hard synthetic resin layer obtained by foaming a mixture of 70-90 wt% of ethylene vinyl acetate (EVA) and 10-30 wt% of conductive carbon. If the amount of ethylene vinyl acetate (EVA) added is less than 70 wt% or the amount of conductive carbon added is more than 30 wt%, the mechanical properties of the shoe insole can be reduced as a resultof the reduction in the amount of addition of ethylene vinyl acetate (EVA), which is excellent in mechanical properties such as elasticity, elongation and tensile strength.
• EVA ethylene vinyl acetate
• the amount of ethylene vinyl acetate (EVA) added is more than 90 wt% or the amount of conductive carbon added is less than 10 wt%, electric charges generated in the human body cannot be smoothly conducted to the ferroelectric elements, such that static electricity generated in the human body cannot be smoothly eliminated, because the amount of conductive carbon added is relatively small compared to the amount of ethylene vinyl acetate (EVA) added.
• the present invention having the above-described construction is based on the principle according to which electric charges generated in the human body are conducted through the top layer and the middle layer, and then charged in the ferroelectric elements, and the remaining electric charges are discharged to the antistatic hard synthetic resin bottom layer through the electric discharge net, thus dissipating electric charges.
• the insole for eliminating static electricity is structured such that a potential of more than 2 kV, generatedin the human body, will be dissipated in the insole within a time of 1-2 seconds, so that static electricity will be eliminated, and finally a potential of less than 0.5 kV, which causes no damage to the human body, will remain.
• the present invention provides the shoe insole for eliminating static electricity, which comprises ferroelectric elements inserted therein, and thus can eliminate static electricity. More particularly, the present invention provides the shoe insole for eliminating static electricity, which has the same external structure as that of general shoe insoles and can be applied to all kinds of shoes so as to efficiently eliminate static electricity generated in the human body.
• FIG. 1 is a cross-sectional view of a prior general shoe for eliminating static electricity
• FIG. 2 shows a shoe for eliminating static electricity according to the present invention
• FIG. 3 shows the arch portion (dotted line) of a normal person
• FIGS. 4 to 6 show a process of assembling the parts of the static electricity- eliminating shoe according to the present invention
• FIG. 7 is a cross-sectional view taken along line C-C in the hard synthetic resin bottom layer of FIG. 5;
• FIG. 8 is a cross-sectional view taken along line D-D' in the hard synthetic resin bottom layer of FIG. 5. Best Mode for Carrying Out the Invention
• An insole for eliminating static electricity which consists of the following parts, was manufactured: a top layer made of a conductive synthetic fabric woven from synthetic resin yarns having silver yarns arranged thereon at a given interval; a middle layer made of a soft foam material obtained by adding 1 part by weight of an azodi- carbonamide foaming agent, 2 parts by weight of zinc oxide and 1 part by weight of magnesium stearate to 100 parts by weight of a mixed base of 70 wt% of ethylene vinyl acetate (EVA) and 30 wt% of conductive carbon and foaming the mixture; and a bottom layer consisting of a hard synthetic resin layer obtained by extruding a mixture of 70 wt% of ethylene vinyl acetate (EVA) and 30 wt% of conductive carbon, wherein a pair of PZN-BT-PT ferroelectric elements and an electric discharge net are inserted between the middle layer and the bottom layer.
• a top layer made of a conductive synthetic fabric woven from synthetic resin yarns having silver yarns
• the electric discharge net was formed using a material having the same composition as that of the soft foam middle layer.
• An insole for eliminating static electricity which consists of the following parts, was manufactured: a top layer made of a conductive synthetic fabric woven from synthetic resin yarns having silver nanoparticle-coated yarns arranged thereon at a given interval; a middle layer made of a soft foam material obtained by adding 2 parts by weight of an azodicarbonamide foaming agent, 2.5 parts by weight of zinc oxide and 1.5 parts by weight of magnesium stearate to 100 parts by weight of a mixed base of 90 wt% of ethylene vinyl acetate (EVA) and 10 wt% of conductivecarbon and foaming the mixture; and a bottom layer consisting of a hard synthetic resin layer obtained by extruding a mixture of 90 wt% of ethylene vinyl acetate (EVA) and 10 wt% of conductive carbon, wherein a pair of PZN-BT-PT ferroelectric elements and an electric discharge net are inserted between the middle layer and the bottom layer.
• a top layer made of a conductive synthetic fabric woven from synthetic resin yarns
• the electric discharge net was formed using a material having the same composition as that of the soft foam middle layer.
• Each of the static electricity-eliminating insoles manufactured in Examples 1 and 2 was placed in a conventional safety shoe and charged to a constant voltage of 6.4 kV.
• the shoes comprising the antistatic insole were brought into contact with the plate of a charged plate analyzer (CPA), and in this state, the remaining potential was measured using a device for measuring human static electricity.
• CPA charged plate analyzer
• the static electricity-eliminating insole according to the present invention is characterized in that it allows static electricity generated in the human body to be dissipated in the shoe insole, such that the static electricity generated causes no damage to the human body.
• FIGS. 4 to 6 show the process in which the parts of the static electricity-eliminating insole are bonded with each other.
• the scope of the present invention is not limited only to the accompanying drawings.
• the static electricity-eliminating insole comprises: a top layer 10 made of a conductive synthetic fabric; a middle layer 20 made of an antistatic soft foam material; and a bottom layer made of an antistatic hard synthetic resin material.
• the PZN-BT-PT ferroelectric elements are circular elements having a circular shape like a coin.
• the ferroelectric elements are subjected to poling treatment, such that the two ferroelectric elements have positive (+) and negative (-) polarities, respectively, whereby the the positive (+) or negative (-) electrode of the ferroelectric elements can absorb and neutralize positive (+) or negative (-) electric charges generated in the human body, and then discharge the electric charges slowly to the hard synthetic resin so as to dissipate the electric charges.
• the electric discharge net 40 is made of a conductive foam material having a horseshoe-shaped network structure, and functions to discharge electric charges from the soft foam middle layer 20 to the hard synthetic resin bottom layer 50.
• a pair of the PZN-BT-PT ferroelectric elements 30 is placed in the [H] -shaped groove formed in the convex arch portion A protruding from the middle portion of the hard synthetic resin bottom layer 50, and the electric discharge net 40 is placed in the [H] -shaped groove formed in the shoe heel portion B of the hard synthetic resin bottom layer 50.
• the PZN-BT-PTferroelectric element pair and the electric discharge net are placed in the hard synthetic resin bottom layer 50, and then the soft foam middle layer 20 is bonded to the upper surface of the bottom layer 50.
• the top layer 10 is bonded to the upper surface of the middle layer 20, as shown in FIG. 2, a static electricity-eliminating shoe, which has a simple shape and the same structure as that of general shoe insoles, is obtained.
• FIG. 7 is a cross-sectional view taken along line C-C in the hard synthetic resin bottom layer of FIG. 5.
• FIG. 7 is a cross-sectional side view, which shows a pair of the PZN-BT-PT ferroelectric elements30 placed in the arch portion A of the hard synthetic resin bottom layer 50, and the electric discharge net 40 placed in the shoe heel portion B.
• FIG. 8 is a cross-sectional view taken along line D-D in the hard synthetic resin bottom layer of FIG. 5.
• the top layer 10 made of the synthetic fiber woven from the silver nanoparticle-coated yarns will receive electric charges generated in the human body and conduct the electric charges to the soft foam middle layer 20. Then, the soft foam middle layer 20 will conduct the electric charges to the PZN-BT-PTferroelectric elements 20 and, at the same time, discharge the remaining electric charges to the antistatic hard syntheticresin bottom layer 50 through the electric discharge net 40, whereby the electric charges generated in the human body will be dissipated in the static electricity-eliminating insole.
• the present invention provides theshoe insole for eliminating static electricity, which comprises ferroelectric elements inserted therein, and thus can eliminate static electricity. More specifically, the present invention provides the shoe insole for eliminating static electricity, which has the same external structure as that of general shoe insoles and can be applied to all kinds of shoes so as to efficiently eliminate static electricity generated in the human body.

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• Health & Medical Sciences (AREA)
• Epidemiology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Footwear And Its Accessory, Manufacturing Method And Apparatuses (AREA)

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• 2006
  • 2006-08-31 KR KR2020060023730U patent/KR200435695Y1/ko not_active IP Right Cessation
• 2007
  • 2007-07-10 KR KR1020087011754A patent/KR100986136B1/ko active IP Right Grant
  • 2007-07-10 WO PCT/KR2007/003328 patent/WO2008026824A1/en active Application Filing
  • 2007-07-10 EP EP07793199A patent/EP2056689A1/en not_active Withdrawn

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