Technical Field
[0001] The present invention relates to an anti-slipping structure for a surface of an article,
an article provided with coating film layer imparting an anti-slipping effect, an
anti-slipping body, gloves, a method for forming coating film layer, and a method
for manufacturing gloves.
Background Art
[0002] Conventionally, a user wears gloves for protecting his/her hands during an operation.
[0003] Among various types of gloves, gloves that are coated with a coating film layer made
of an elastic material such as natural rubber, synthetic rubber, polyvinyl chloride,
polyurethane have been popularly used. This is because such gloves exhibit excellent
functions such as high waterproof property, high oil resistant property and high chemical
resistant property while maintaining flexibility.
[0004] However, when a surface of the coating film layer is made flat and smooth, for example,
when the surface of the coating film layer is wetted, a friction generated between
the coating film layer and the gripping article is small and hence, there may be a
case where it is difficult for a user to grasp the article.
[0005] In view of such a circumstance, there has been proposed a method where an elastic
material before solidification is made to adhere to a surface of a glove base body
that forms a base of the glove, predetermined powder is further made to adhere to
the elastic material before its solidification, the elastic material is solidified
and, thereafter, the powder is removed by melting or the like so that fine recessed
portions are formed on a surface of a coating film layer that covers an outermost
portion of the glove. Such a method is also referred to as a powder adhesion method
(for example, see patent literature 1).
[0006] With such a configuration, a friction force that acts between the glove and a grasping
article can be increased and hence, operability of a user in a state where the user
wears the gloves can be enhanced.
Citation List
Patent Literature
Summary of Invention
Technical Problem
[0008] However, the conventional gloves formed by the above-mentioned powder adhesion method
have a drawback that small dust is likely to be filled in the fine recessed portions
formed on the surface of the coating film layer.
[0009] Further, although gloves formed by a powder adhesion method are gloves having excellent
operability, there has been a demand for gloves having a larger friction force.
[0010] In view of the above-mentioned problems, the inventors of the present invention have
made extensive studies so as to develop gloves where dust is minimally filled in recessed
portions and a larger friction force can be generated compared to gloves that are
obtained by a powder adhesion method. As a result, the inventors cast off the conventional
technical concept that requires powdery body as an indispensable constituent for forming
recessed portions, and have found a novel method that can overcome such problems of
the conventional method by making use of a property of a liquid, and also have found
that the novel method is not only applicable to surfaces of gloves simply but also
applicable to the prevention of a slippage relating to articles in a broad range.
The present invention has been made based on such finding. Solution to Problem
[0011] To overcome the above-mentioned conventional drawback, (1) according to an aspect
of the present invention, there is provided an anti-slipping structure for an article
surface that includes, on a surface of a coating film layer that covers a surface
of an article, a plurality of hemispherical recessed portions each having an approximately
circular shape as viewed in a plan view, and a plurality of diaphragm provided recessed
portions formed such that two or more hemispherical recessed portions are connected
to each other in a partially overlapping manner and a connection boundary between
the recessed portions is partitioned by a diaphragm.
[0012] (2) According to another aspect of the present invention, there is provided an article
having a coating film layer which covers a surface of an article and on which a plurality
of recessed portions are formed for imparting an anti-slipping effect to the article,
wherein the plurality of recessed portions are formed of: a plurality of hemispherical
recessed portions having an approximately circular shape as viewed in a plan view;
and a plurality of diaphragm provided recessed portions formed such that two or more
hemispherical recessed portions are connected to each other in a partially overlapping
manner and a connection boundary between the recessed portions is partitioned by a
diaphragm.
[0013] (3) According to another aspect of the present invention, there is provided an anti-slipping
body, wherein the anti-slipping body is the article described in the configuration
(2), and is disposed on other articles so as to impart an anti-slipping effect to
the other articles.
[0014] (4) According to another aspect of the present invention, there is provided gloves
where a plurality of recessed portions are formed on a coating film layer that covers
surfaces of the gloves, wherein the plurality of recessed portions are formed of:
a plurality of hemispherical recessed portions having an approximately circular shape
as viewed in a plan view; and a plurality of diaphragm provided recessed portions
formed such that two or more hemispherical recessed portions are connected to each
other in a partially overlapping manner and a connection boundary between the recessed
portions is partitioned by a diaphragm.
[0015] (5) According to another aspect of the present invention, there is provided a method
for forming a coating film layer which covers a surface of an article and on which
a plurality of recessed portions are formed so as to impart an anti-slipping effect
to the article, wherein a liquid droplet of a solidifying agent is made to impinge
on an unsolidified elastic material that adheres to the surface of the article so
as to recess and solidify impinged portions thus forming the recessed portions.
[0016] (6) According to another aspect of the present invention, in the method for forming
a coating film layer, the article is an anti-slipping body that imparts an anti-slipping
effect to other articles by being disposed on the other articles.
[0017] (7) According to another aspect of the present invention, there is provided a method
for manufacturing gloves where a plurality of recessed portions are formed on a coating
film layer that covers surfaces of the gloves, wherein a liquid droplet of a solidifying
agent is made to impinge on an unsolidified elastic material that adheres to the surface
of an unfinished article formed in a profile of fingers so as to recess and solidify
impinged portions thus forming the recessed portions.
[0018] (8) According to another aspect of the present invention, there is provided a method
for manufacturing gloves where anisotropy is imparted to the recessed portions by
applying a tension to the elastic material. Advantageous effects of Invention
[0019] According to the anti-slipping structure for an article surface of the present invention,
the anti-slipping structure includes, on the surface of the coating film layer that
covers the surface of the article, the plurality of hemispherical recessed portions
each having an approximately circular shape as viewed in a plan view, and the plurality
of diaphragm provided recessed portions formed such that two or more hemispherical
recessed portions are connected to each other in a partially overlapping manner and
the connection boundary between the recessed portions is partitioned by a diaphragm.
With such a configuration, compared to an anti-slipping structure that is formed by
powder adhesion method, dust is minimally filled in the recessed portions, and a larger
friction force can be generated.
[0020] According to the article of the present invention having the coating film layer
that imparts an anti-slipping effect, wherein the article is the article that includes
the coating film layer which covers a surface of the article on which the plurality
of recessed portions are formed so as to impart an anti-slipping effect to the article,
and the plurality of recessed portions are formed of: the plurality of hemispherical
recessed portions having an approximately circular shape as viewed in a plan view;
and the plurality of diaphragm provided recessed portions formed such that two or
more hemispherical recessed portions are connected to each other in a partially overlapping
manner and the connection boundary between the recessed portions is partitioned by
the diaphragm. With such a configuration, compared to an article that has an anti-slipping
effect obtained by a powder adhesion method, it is possible to provide the article
where dust is minimally filled in the recessed portions, and a larger friction force
can be generated
[0021] Further, in the case where the article described above is formed of the anti-slipping
body that is disposed on other articles so as to impart an anti-slipping effect to
the other articles, it is possible to easily impart an excellent anti-slipping effect
to various objects that are desirable to be imparted with an anti-slipping effect
such as a chair, a table, a floor surface, treads of a stair and a handrail, for example.
[0022] According to another aspect of the present invention, there is provided gloves where
a plurality of recessed portions are formed on a coating film layer that covers surfaces
of the gloves, wherein the plurality of recessed portions are formed of: a plurality
of hemispherical recessed portions having an approximately circular shape as viewed
in a plan view; and a plurality of diaphragm provided recessed portions formed such
that two or more hemispherical recessed portions are connected to each other in a
partially overlapping manner and a connection boundary between the recessed portions
is partitioned by a diaphragm. With such a configuration, compared to gloves obtained
by a powder adhesion method, it is possible to provide the gloves where dust is minimally
filled in the recessed portions, and a larger friction force can be generated
[0023] According to the method for forming a coating film layer on which a plurality of
recessed portions are formed so as to cover a surface of an article for imparting
an anti-slipping effect to the article, wherein a liquid droplet of a solidifying
agent is made to impinge on an unsolidified elastic material that adheres to the surface
of the article so as to recess and solidify the impinged portions thus forming the
recessed portions. With such a configuration, with respect to various articles, compared
to gloves obtained by a powder adhesion method, it is possible to provide the gloves
where dust is minimally filled in the recessed portions, and a larger friction force
can be generated
[0024] In the case where the article is an anti-slipping body that imparts an anti-slipping
effect to other articles by being disposed on the other articles, it is possible to
easily impart an excellent anti-slipping effect to various objects that are desirable
to be imparted with an anti-slipping effect.
[0025] According to the method for manufacturing gloves of the present invention where the
plurality of recessed portions are formed on the coating film layer that covers the
surfaces of the gloves, wherein a liquid droplet of a solidifying agent is made to
impinge on an unsolidified elastic material that adheres to the surface of the unfinished
article formed in the profile of the fingers so as to recess and solidify impinged
portions thus forming the recessed portions. With such a method, compared to gloves
that have an anti-slipping effect obtained by a powder adhesion method, it is possible
to manufacture the gloves where dust is minimally filled in the recessed portions,
and a larger friction force can be generated.
[0026] Further, in the case where anisotropy is imparted to the recessed portions by applying
a tension to the elastic material, it is possible to easily remove dust that enters
the recessed portion, it is also possible to impart anisotropy to a generated friction
force.
Brief Description of Drawings
[0027]
Fig. 1 is an explanatory view illustrating a surface structure of gloves according
to the present embodiment.
Fig. 2 is an explanatory view illustrating a surface structure of gloves formed by
a powder adhesion method.
Fig. 3 is an explanatory view illustrating a cross-sectional structure of the gloves
according to the present embodiment.
Description of Embodiments
[0028] The present invention relates to an anti-slipping structure for an article surface,
and an article an anti-slipping body, and gloves having a coating film layer that
imparts an anti-slipping effect, wherein a plurality of recessed portions are formed
on the coating film layer that covers a surface of the article. The present provides
the gloves where dust is minimally filled in the recessed portions and a larger friction
force can be generated compared to gloves obtained by a powder adhesion method.
[0029] To further describe the present invention, the present invention relates to an article
that includes a coating film layer that imparts an anti-slipping effect. Further,
the present invention also proposes an anti-slipping structure that is formed on a
surface of the article, a structure where one specific mode of the article is a so-called
anti-slipping body itself, and a structure where a specific one mode of the article
is gloves.
[0030] In this embodiment, the article is not particularly limited provided that the anti-slipping
structure according to the embodiment can be formed. In this embodiment, the description
will be made by focusing on gloves as one mode of the article. However, it is sufficient
that the article is an article that satisfies the above-mentioned condition, and the
article includes, various articles, for example, socks, slippers, shoes, mats, and
a chair, a table, a floor surface, treads of a stair, a handrail as described above.
[0031] Further, it is sufficient that the anti-slipping body has configuration that can
be disposed on articles that are desirable to be imparted with an anti-slipping effect.
The anti-slipping body may take a mode such as an adhesive tape or a tacky adhesive
pad, or may be formed in a plate shape so that the anti-slipping body can be fixed
by bolts or the like, or may take a mode where the anti-slipping mode does not an
adhering or fixing means and is only disposed.
[0032] The anti-slipping structure according to the present embodiment is the structure
for anti-slipping that is commonly used by the article, the anti-slipping body, the
gloves and the like according to the present embodiment, and is one large technical
feature of the present invention. The specific technical features of the anti-slipping
structure are described hereinafter with respect to the case where the object on which
the anti-slipping structure or the object on which the anti-slipping body is disposed
is gloves. Accordingly, the specific technical features are described together with
the description of such a case.
[0033] The gloves according to the present invention are formed such that a plurality of
recessed portions are formed on the coating film layer that covers the surface. With
such a configuration, compared to glove that are obtained by a powder adhesion method,
dust is minimally filled in the recessed portions and, further, a larger friction
force can be generated.
[0034] The gloves according to the present embodiment may be unsupported-type gloves where
a glove base body is not used and a coating film layer is formed on a surface of a
resin film, or may be supported-type gloves that use a glove base body and a coating
film layer is formed on a surface of the glove base body directly or by way of a predetermined
resin film.
[0035] That is, a semi-finished article that is an object on which a coating film layer
that covers a surface of the gloves may be either a type of semifinished article that
does not use a glove base body or a type of semi-finished article that uses a glove
base body. Using such a semi-finished article, it is possible to provide gloves according
to the present embodiment on which an anti-slipping structure that includes a plurality
of recessed portions on the coating film layer on the surface of the semifinished
article is formed. The recessed portions on the surface of the gloves may be formed
on the entire surface of the resin film or may be partially formed on the surface
of the resin film. In this embodiment, the semifinished article means a semifinished
article that is in a process of forming the gloves according to the embodiment. The
semifinished article does not mean an article that is used in a case where the gloves
according to the present embodiment is used as a semifinished article in a manufacturing
process of a secondary processed article that uses the gloves according to the embodiment
as a semifinished article. However, the present invention may include such a case.
[0036] As the glove base body, for example, gloves that are formed using a knitted fabric
or a woven fabric can be named. The raw material of the glove base body is not particularly
limited, and the following various raw materials can be used. For example, as natural
fibers, cotton, silk floss, hemp, wool and the like are named. As synthetic fibers,
nylon, vinyl, polyvinyliden chloride, polyvinyl dichloride, polyester, polyurethane,
rayon, cuprammonium rayon, acetate, acryl, polypropylene, polyethylene, fluorocarbon
fibers, polychlal fibers, aramid fibers, cellulose, glass fibers and the like are
named.
[0037] A material for forming a coating film layer that covers a surface of gloves according
to the present embodiment, that is, an elastic material that is made to adhere to
a surface of the glove base body that is also a semifinished product of the gloves
in manufacturing steps of the gloves according to the present embodiment contains
a solidifying agent that changes the elastic material from an unsolidified state to
a solidified state. The solidifying agent can be prepared as a solution. Further,
it is sufficient for the solidifying agent that the elastic material is speedily solidified
to an extent that impingement traces remain at contact portions when an unsolidified
elastic material comes into contact (impingement) with a liquid droplet of the solidifying
liquid. As an elastic material used in general for forming a film by a solidification
method, for example, natural rubber, synthetic rubber, (for example, acrylonitrile
butadiene rubber (NBR), polyurethane and the like are named.
[0038] The solidification method is a method that forms a resin composition into a gel form
by salt solidification, solidification by an acid, or solidification by an organic
solvent.
[0039] A resin composition which is an object to be solidified is natural rubber or synthetic
rubber, as a solidification agent for solidifying such resin composition using by
salt solidification, for example, a methanol solution in which metal salt such as
calcium nitride, calcium chloride is dissolved, or aquas solution can be used. Further,
as an acid that forms a solidification agent for solidifying by an acid, an organic
acid such as an acetic acid or citrate can be used. Although the solidification can
be performed by performing either one of solidification using metal salt or solidification
using an acid in a single form, both solidifications can be used in combination.
[0040] Further, when the resin composition that is an object to be solidified is polyurethan,
as a solidification agent for solidifying polyurethan by solidification using an organic
solvent, for example, an organic solvent such as a heptane can be used.
[0041] A thickness of the coating film layer is preferably 0.05 to 2mm. There is a tendency
that the thicker the resin film, the harder the portion becomes.
[0042] The thinner a thickness of the coating film layer, the larger the flexibility of
the coating film layer becomes and hence, fitting property or property that the coating
film layer suits a hand can be improved. However, a strength of the gloves is lowered
and hence, when the gloves are used for a heavy work, it is necessary for the coating
film layer to have a certain amount of thickness. However, it must be particularly
noted that there is a tendency that, compared to gloves formed by powder adhesion
method, a surface portion and recessed portions of the coating film layer become smooth.
Further, a depth of the recessed portion with respect to a diameter of an opening
of the recessed portion is shallow and hence, a strength of the coating film layer
when the coating film layer is formed with the substantially same thickness is increased
compared to the gloves formed by a powder adhesion method.
[0043] The coating film layer fairly differs in softness and texture also depending on a
raw material. For example, even when the coating film layer has the same thickness,
there is a tendency that the coating film layer made of a low modulus raw material
such as natural rubber or a soft polyvinyl chloride is soft, and the coating film
layer made of high modulus raw material such as nitrile rubber becomes hard.
[0044] Further, as a technical feature of the gloves according to the present embodiment,
a plurality of recessed portions of the anti-slipping structure according to the present
embodiment formed on the coating film layer includes: hemispherical recessed portions
having an approximately circular shape as viewed in a plan view; and diaphragm provided
recessed portions where two or more hemispherical recessed portions are connected
to each other in a partially overlapping manner, and a bonding boundary between the
hemispherical recessed portions is partitioned by a diaphragm wall.
[0045] In such a configuration, "hemispherical shape" is not always limited to an accurately
hemispherical shape, and also includes a recessed portion that is slightly shallower
than a hemispherical shape, and a recessed portion having an elliptical shape as viewed
in a plan view. Further, the term "approximately circular shape" that expresses the
shape as viewed in a plan view is also not limited to an accurate circle. That is,
it is sufficient that a most portion of an opening edge of the recessed portion having
an annular shape is protruding outward at an opening edge, and forms a substantially
continuous curve. For example, in Fig. 1(a), the recessed portion indicated by a black
flame is a hemispherical recessed portion. To facilitate the understanding of the
present invention, the recessed portion indicated by the black frame exemplifies a
portion of the hemispherical recessed portion illustrated in Fig. 1(a). That is, it
must be noted that it is not always the case that only the recessed portions indicated
by the black frame exhibit all hemispherical recessed portion, and some hemispherical
recessed portions that are not indicated by the black frame exist together with the
recessed portions that do not form the hemispherical recessed portions.
[0046] The diaphragm provided recessed portion is a recessed portion having the structure
where two or more hemispherical recessed portions are connected with each other in
a partially overlapping manner, and the bonding boundary is partitioned by the diaphragm
wall. With respect to such a diaphragm provided recessed portion, a liquid droplet
of a solidification solution impinges on an area extremely close to the hemispherical
recessed portion that is already formed so that a new hemispherical recessed portion
is formed in such a manner that a portion of the previously formed hemispherical recessed
portion is eroded. As a result, for example, as indicated by a frame in a broken line
in Fig. 1(b), the diaphragm provided recessed portion is formed of the eroded recessed
portion derived from the previously formed hemispherical recessed portion and the
hemispherical recessed portion.
[0047] Further, in the boundary portion between the eroded recessed portion and the hemispherical
recessed portion, an elastic material whose thicknesses increased in an offset manner
by an impingement of the solidification liquid when the above-mentioned new hemispherical
recessed portion is formed forms the diaphragm wall that is bent in a convex shape
toward the inside in the previous semispherical recessed portion. In many cases, this
diaphragm wall is thinner than a wall around the hemispherical recessed portion formed
independently. It is considered that the diaphragm wall plays a role of increasing
a friction force by entangling with an object to be gripped.
[0048] Further, as a technical feature that is shared in common by the hemispherical recessed
portion and the diaphragm provided recessed portion, most of these recessed portions
do not have an overhung shape.
[0049] That is, as indicated by a black triangular arrow in Fig. 2(a) that is a cross-sectional
view, a recessed portion formed by a powder adhesion method is derived from a particle
embedded in a coating film layer and hence, an overhang portion is formed by an inner
space having a diameter larger than a diameter of an opening of the recessed portion.
[0050] With respect to such a recessed portion having many overhung portions, dust that
enters the recessed portion and worn-out debris of the coating film layer are hardly
removed and hence, the recessed portion is filled with these dust and debris.
[0051] Further, a wall having an overhung shape that is formed between two recessed portions,
for example, the wall indicated by a white triangular arrow and a white broken line
in Fig. 2(a) is fragile or weak because the wall has a portion having a thin wall
thickness ranging from a surface layer to a deep portion of the coating film layer
and hence, the portion of the wall falls by friction so that the generation of dust
is promoted.
[0052] As a result, as illustrated in Fig. 2(b), along with a shape of an opening edge as
viewed in a plan view where the opening edge exhibits an uneven amorphous shape, a
concentration of a stress derived from a friction force is brought about and hence,
a lump of a portion of the coating film layer falls.
[0053] Further, as described above, in the structure described above where the wall thickness
is gradually decreased from the surface layer to the depth portion, excessive flexibility
is imparted to the wall. As a result, the coating film layer decreases an effect of
sucking an object to be gripped like suction cups (a so-called suction cup effect).
Accordingly, because of a rough surface shape where a base line is not determined
as illustrated in Fig. 2(a), a leakage of air is likely to occur and hence, it is
difficult to maintain a sufficient negative pressure in the recessed portion.
[0054] To the contrary, the recessed portion of the gloves according to the present embodiment
does not have an overhung portion in most cases as illustrated in Fig. 3, that is,
a cross-sectional view. Accordingly, even when dust or worn-out debris of the coating
film layer enters the recessed portion, the dust or the debris can be easily removed
and hence, it is possible to prevent the recessed portion from being filled with the
dust or the debris. It is not always the case where a group of recessed portions that
form the anti-slipping structure of the gloves according to the present embodiment
exclude the recessed portions having the overhung structure in the strict meaning
of the term. That is, the presence of the recessed portions having the overhung structure
is allowed more or less to an extent that the superiority of the above-mentioned advantageous
effects against the conventional products is not impaired.
[0055] Further, as indicated by a white triangular arrow and a white broken line in Fig.
3, the wall formed between two hemispherical recessed portions has a gentle mountain-like
shape and also has a shape having a large wall thickness, that is, a shape having
a large wall thickness and minimally generating the concentration of a stress. Accordingly,
the generation of dust such as a lump of a portion of the coating film layer that
falls is hardly promoted.
[0056] Further, the wall having a gentle mounting-like shape has appropriate flexibility.
The wall has the structure where a base surface (base line) that corresponds to a
surface before the recessed portions are formed is relatively clear and portions other
than the recessed portions are relatively flat and smooth. Accordingly, a leakage
of air is small and hence, a negative pressure in the recessed portion can be sufficiently
maintained whereby a suction cup effect can be effectively generated.
[0057] Further, to describe the unique structure of the gloves according to the present
invention using another expression, for example, it is also safe to say that the structure
of the gloves according to the present invention is the anti-slipping surface structure
of the gloves where, while forming the main body by the flat smooth wall structure
having a large wall thickness that is formed between a curved surface that forms a
side wall of one flat smooth recessed portion having a hemispherical shape or a hemi-elliptical
shape and a curved surface that forms a side wall of the other flat smooth recessed
portion disposed adjacently to the former flat smooth recessed portion, portions also
exist where the other ellipse is formed on one ellipse in an overlapping manner (one
ellipse being formed by erosion by the other ellipse) so that a portion where a thin
wall thinner than the flat smooth wall having the above-mentioned wall thickness in
the above-mentioned one ellipse exists.
[0058] Further, to describe the unique structure of the gloves according to the present
invention using different expression, for example, it is also safe to say that the
structure of the gloves according to the present invention is the anti-slipping surface
structure of the gloves where, while forming the main body by the flat smooth wall
structure having a large wall thickness that is formed between a curved surface that
forms an inner wall of one ellipse and a curved surface that forms an inner wall of
the other ellipse disposed adjacently to the one ellipse, portions also exist where
the other ellipse is formed on one ellipse in an overlapping manner (one ellipse being
formed by erosion by the other ellipse) so that a thin wall that is thinner than the
flat smooth wall having the above-mentioned wall thickness in the above-mentioned
one ellipse.
[0059] Further, in this specification, a method for manufacturing gloves having such technical
features is also provided. More specifically, in a method for manufacturing gloves
where a plurality of recessed portions are formed on a coating film layer that covers
surfaces of the gloves, a liquid droplet of a solidifying agent is made to impinge
on an unsolidified elastic material that adheres to the surface of an unfinished article
formed in a profile of fingers so as to recess and solidify impinged portions thus
forming the recessed portions.
[0060] In this method, in the same manner as described above, the semifinished article may
be a resin film formed in a shape of a profile of fingers without using a glove base
body. Further, a glove base body formed using a knitted fabric or a woven fabric,
or a glove base body having a surface on which a resin film is formed may be also
used as the semifinished article.
[0061] Further, it is not always necessary for the semifinished article to accurately trace
the shape of the profile of fingers, and it is also unnecessary for the semifinished
article trace the entirety of the shape of the profile of fingers. For example, the
semifinished article may have the shape of a mitten or the like, or may be formed
such that some fingers are exposed from the semifinished article.
[0062] First, an unsolidified elastic material is made to adhere to the surface of such
a semifinished article. The adhesion of the elastic material may be performed by applying
an elastic material to the semifinished article by coating, or by immersing the semifinished
article into the elastic material.
[0063] Liquid droplets of a solidifying agent that is an elastic material is made to impinge
on the elastic material that adheres to the semifinished article. Although the impingement
of the liquid droplets may be performed using a spray of the like, a method of generating
the impingement of the liquid droplets is not particularly limited provided that kinetic
energy can be imparted to the liquid droplets to an extent that recesses can be formed
on the surface of the elastic material when the liquid droplets impinge on the elastic
material. By performing such a step, the hemispherical recessed portions and the diaphragm
provided recessed portions are formed on a surface of the elastic material.
[0064] Then, gloves are manufactured by solidifying the elastic material on which such recessed
portions are formed to a deep portion when necessary.
[0065] Further, a compounding agent may be added to the elastic material when necessary.
As the compounding agent, a stabilizer, a cross-linking agent, a cross-linked dispersion
agent, an anti-aging agent, a thickener, a plasticizer, an antifoaming agent and the
like can be used. Amounts of these compounding agents can be suitably adjusted depending
on a usage of gloves.
[0066] Among the above-mentioned compounding agents, a cross-linked dispersion agent can
be obtained by dispersing, besides a cross-linking agent such as sulfur or peroxide,
a solid material such as a cross-linking promoter such as BT, TT, CZ, PZ, a cross-linking
promoting aid such as zinc oxide or an anti-aging agent into water. The cross-linking
dispersion agent is mainly used when a resin composition is a rubber latex. With the
use of the cross-linking agent, rubber molecules are bonded to each other in a mesh
shape so that physical property such as a strength of the resin film can be increased.
[0067] Further, in the method for manufacturing gloves according to the present embodiment,
anisotropy may be imparted to the recessed portions formed by imparting a tension
to the elastic material.
[0068] That is, although the recessed portions are formed, by imparting a tension in a predetermined
direction among plane directions to the elastic material before the elastic material
is completely solidified, for example, the respective recessed portions of a group
of recessed portions formed in a circular shape can be deformed in an elliptical shape
having a major axis oriented in the respective predetermined directions thus imparting
anisotropy. In the description made hereinafter, the directions of major axes of the
group of recessed portions deformed in an elliptical shape are also referred to as
orientation directions.
[0069] By applying such processing, dust in the recessed portions can be easily removed,
and it is possible to generate anisotropy in the manner of generating a friction force.
[0070] An opening diameter of the recessed portion, for example, an opening diameter of
the hemispherical recessed portion is not particularly limited. However, to estimate
gloves having high general-used-property that does not particularly limit an object
to be grasped, if the opening diameter is to be referred, the opening diameter can
be set to 0.5 mm or less, further, approximately 0.01 to 0.5 mm, and more preferably
approximately 0.05 to 0.25 mm.
[0071] The gloves according to the present embodiment can be manufactured through the following
steps in general when the gloves are of a support type, for example.
- (1) A hand mold is covered by a knitted glove base body, and a temperature of the
mold is adjusted, and the glove base body is immersed in a solidifying agent.
- (2) The glove base body is immersed in a resin composition, is pulled up, and is dried.
Depending on necessity, the glove base body is immersed several times so that a film
that acts as an infiltration prevention film is formed. The resin composition that
forms this infiltration prevention film may be the same resin composition for forming
a coating film layer described later or may be different from the resin composition
for forming the coating film layer.
- (3) Then, the glove base body is immersed in the resin composition for forming the
coating film layer, and before the resin composition is solidified, while imparting
kinetic energy for forming recessed portions to liquid droplets made of of a solidifying
agent, the liquid droplets are made to impinge on a surface of the elastic material.
- (4) The coating film layer is solidified through drying and cross-linking, and the
glove is removed from the hand mold. A cross-linking step can be omitted depending
on a resin used in the manufacturing method.
[0072] Except for the presence or absence of the glove base body, the gloves of an unsupported
type are manufactured by substantially the same manufacturing method as gloves of
a support type and hence, description of the method for manufacturing the gloves of
an unsupported type is omitted. Further, flocking may be applied to the inside of
the gloves.
[0073] Further, as a still another mode, bubbles may be contained in the coating film layer
of the gloves according to the present embodiment. In this mode, the term "bubbles"
is used with also a meaning that the bubbles indicate portions that contain a gas
in a liquid body or solid body, and portions formed into recessed portions where a
portion or most portion of the bubble opens on a surface of the solid body so that
the recessed portions do not contain a gas, for example, traces after foam breaking.
[0074] As a method for allowing the coating film layer to contain bubbles or to form traces
after foam breaking, a method that allows an elastic material that is a material for
forming the coating film layer to contain bubbles is maned. As the method that allows
the elastic material to contain bubbles, for example, a method that uses mechanical
foaming or a method that uses chemical foaming can be named.
[0075] In the method for generating bubbles by a machine, for example, an elastic material
in an unsolidified state is stirred by a stirrer such as a mixer thus allowing the
elastic material to contain bubbles.
[0076] As a method for chemically generating bubbles, a foaming agent is added to an elastic
material in an unsolidified state, and the foaming agent is formed into bubbles by
applying heat to the foaming agent at the time of molding gloves thus allowing the
elastic material to contain bubbles.
[0077] The foaming agent is a chemical that is also used in the manufacture of a sponge
product. The foaming agent is decomposed when heat is applied to the foaming agent,
and generates gasses such as a carbon dioxide gas, a nitrogen gas, and ammonia thus
forming the bubble structure. As a specific examples of the foaming agent, an inorganic
foaming agent such as soda or ammonium carbonate or an organic foaming agent such
as a nitroso compound, an azo compound, or a sulfonyl hydrazide can be named.
[0078] In general, it seems that by adopting a mechanical foaming method rather than a chemical
foaming method, bubbles can be easily uniformly or approximately uniformly dispersed
in the elastic material. By dispersing the bubbles uniformly or approximately uniformly,
bubbles contained in the coating film layer obtained by solidification of the elastic
material can be also uniformly or approximately uniformly dispersed.
[0079] An amount of bubbles contained in the coating film layer may preferably be 5 to 30
vol% with respect to a unit volume of the coating film layer. When an amount of bubbles
is less than 5 vol%, a sufficient anti-slipping effect cannot be obtained and hence,
such amount of babbles is not preferable. When an amount of bubbles exceeds 30 vol%.
although an anti-slipping effect and flexibility are sufficient, wear resistance is
deteriorated so that durability is lowered. Accordingly, an amount of bubbles exceeding
30 vol% is not preferable.
[0080] In a case where a liquid such as water or oil is treated, due to porosity of the
coating film layer that contains bubbles, there is a possibility that a liquid infiltrates
into the resin film. To prevent the infiltration of the liquid into the resin film
and reaches a hand side, it is possible to form a resin film that does not contain
bubbles and functions as an infiltration prevention diaphragm against a liquid on
a lower side of the coating film layer.
[0081] By providing the resin film that does not contain bubbles, a strength of gloves
can be enhanced. The resin film that does not contain bubbles can be formed by using
the same material as the elastic material that formed the coating film layer. From
a viewpoint of an adhesion property, such usage is preferable. In a case of gloves
that do not treat a liquid such as water or oil, a resin film that functions as an
infiltration prevention film and does not contain bubbles can be omitted.
[0082] In this manner, the gloves and the method for manufacturing gloves according to the
present embodiment include the above-mentioned configurations. However, as described
above, it must be noted that these configurations are not always configurations that
are limited to the gloves, and are applicable to various articles.
[0083] Hereinafter, with respect to the anti-slipping structure of the article surface,
the article having the coating film layer that imparts an anti-slipping effect, the
anti-slipping body, the gloves, the method for forming the coating film layers and
the method for manufacturing the gloves according to the present embodiment, the gloves
and the method for manufacturing the gloves according to the present embodiment are
mainly described with reference to an actual manufacturing example. Hereinafter, the
gloves of a support type that do not contain bubbles in the coating film layer are
described as an example. However, it is needless to say that the present invention
also includes the gloves that contain bubbles in the coating film layer as described
above, and the gloves of an unsupported type.
[1. Manufacture of gloves]
[0084] In the manufacture of the gloves of a support type, first, the preparation of a natural
rubber blended liquid for forming an infiltration prevention film and a coating film
layer, and preparation of a solidifying liquid were performed. Specifically, with
respect to 100 parts by weight of a rubber solid amount of a natural rubber latex
(rubber solid amount 60 weight %), 1 parts by weight of a stabilizer, 1 parts by weight
of sulfur, 0.5 parts by weight of vulcanization promoting agent EZ (zinc diethyldithiocarbamate),
1 parts by weight of zinc white, and 0.5 parts by weight of thickener are added, and
these compositions are stirred so that natural rubber blended liquid was obtained.
Further, the solidifying liquid was obtained by preparing 3 weight % of calcium nitrate
methanol solution.
[0085] Next, using the natural rubber blended liquid obtained as described above, the following
treatment was applied to the glove base body.
[0086] First, a hand mold was covered with a knitted glove base body. The hand mold covered
with the glove base body was immersed into an immersion vessel willed with a solidifying
agent (3 weight % of calcium nitrate methanol solution) and, thereafter, the mold
is pulled out and was dried.
[0087] Next, the hand mold was immersed in an immersion vessel filled with a natural rubber
blended liquid, and thereafter, the hand mold was pulled out, and was dried at a temperature
of 70°C for 30 minutes. Accordingly, a semifinished article where an infiltration
prevention film formed by a natural rubber blended liquid is formed on a surface of
the glove base body was formed.
[0088] Next, the above-hand mold on which the semifinished article provided with the infiltration
prevention film is again immersed in the immersion vessel filled with the natural
rubber blended liquid. Then, after the mold is pulled up from the immersion vessel,
before the natural rubber blended liquid on the surface of the hand mold was solidified,
using a sprayer on which a spray nozzle is mounted, a solidifying agent is sprayed
at a pressure of 0.1 to 1.0 MPa to the hand mold at a position spaced apart from the
hand mold by 10 to 30 cm so as to impinge liquid droplet of the solidifying agent
to the hand mold. The spray nozzle is not particularly limited, and a commercially
available spray nozzle can be suitably adopted. For example, a hollow conical nozzle
(No. K040) or a fan shaped nozzle (No. VEP90157) made by H. IKEUCHI Co., Ltd. can
be used. Further, with respect to a liquid feeding pressure and a distance from the
spray nozzle to a surface to be sprayed, the above-mentioned values exemplify one
example and are not particularly limited. In short, it is sufficient that when liquid
droplets of a solidifying liquid reach a surface of an elastic material adhering to
the semifinished article, recessed portions can be formed by an impact of the liquid
droplets. It is needless to say that such pressure and distance respectively differ
depending on the configuration of the device or the like used for performing the above-mentioned
operation. It is not difficult to find out these values, and can be determined by
adopting conditions for forming recessed portions by observing several samples which
differ in pressure and distance using a microscope or the like.
[0089] In case of forming the coating film layer described above that contains bubbles,
the formation of such a coating film layer can be realized by allowing a natural rubber
blended liquid to contain bubbles as an unsolidified elastic material that is made
to adhere to the semifinished article. For example, the natural rubber blended liquid
was stirred by a mixer thus performing mechanical foaming. Stirring can be performed
until a volume rate of bubbles occupying in the entire natural rubber blended liquid
becomes 5 to 30 vol%, as an example, approximately 20vol%. In this case, stirring
is continuously performed until the volume of the natural rubber blended liquid of
100 mL contains bubbles exceeds 120 ml. By confirming a change in volume at the same
weight before and after foaming using a measuring cylinder, an amount of bubbles contained
in the natural rubber blended liquid can be confirmed.
[0090] Then, after drying the coating film layer at a temperature of 80°C for sixty minutes,
cross linking is performed at a temperature of 110°C for forty minutes. As a result,
the gloves according to the present embodiment was obtained.
[2. Observation of structure of surface of gloves by microscope]
[0091] Next, a surface of the obtained gloves was observed by a microscope. As a result,
it was confirmed that as illustrated in Fig. 1(a), a large number of (a plurality
of) recessed portions are formed on the surface of the coating film layer, and the
plurality of recessed portions include a large number of hemispherical recessed portions
indicated by a block frame in Fig. 1(a) and a large number of diaphragm provided recessed
portions indicated by a broken line frame in Fig. 1(b).
[0092] As illustrated in Fig. 1(a), the respective recessed portions in portions where a
tension is applied to the gloves before the coating film layer is completely solidified
are deformed into an elliptical shape, and a major axis of the elliptical shape is
substantially directed in a fixed direction thus exhibiting anisotropy.
[3. Test for confirming that recessed portions are minimally filled with dust]
[0093] Next, a test was performed so as to confirm that the recessed portions are minimally
filled with dust and dust can be easily removed from the recessed portions. Specifically,
a comparison specimen having a size of 5 cm × 5 cm that was cut out from a palm portion
of the glove manufactured by a powder adhesion method and a specimen obtained in the
same manner from the glove according to the present invention are used. The specimen
was made to adhere to an upper surface of a desk in a state where the coating film
layer is directed upward, soil was rubbed against the coating film layer 10 times,
a weight of coating film layer was measured except for surplus soil on the coating
film layer, and an amount of dust filled in the recessed portion was obtained by obtaining
the difference between the specimen on which the soil was not rubbed and a weight
of the specimen before rubbing was performed.
[0094] Then, dust was shaken off by beating the specimen with a hand 100 times and, again,
the weight of the specimen was measured and the difference between the measured weight
and the weight of the specimen after soil was rubbed was obtained. As a result, an
amount of dust that was removed from the recessed portion was confirmed.
[0095] Five specimens in total ware obtained such that one specimen was obtained from each
of the five gloves manufactured by a powder adhesion method. In the same manner, five
specimens in total ware obtained such that one specimen was obtained from each of
five gloves according to the present embodiment. The substantially same test was performed
five times for each glove. The result of the test performed with respect to the gloves
manufactured by the powder adhesion method are described in Table 1, and the result
of the test performed with respect to the gloves according to the present embodiment
are described in Table 2.
[Table 1]
|
gloves manufactured by powder adhesion method |
first time |
second time |
third time |
fourth time |
fifth time |
average |
experimenter |
A |
B |
C |
D |
E |
|
weight of specimen (W1) |
1.757 |
1.730 |
1.812 |
1.784 |
1.894 |
1.795 |
weight after rubbing 10 times (W2) |
1.796 |
1.770 |
1.897 |
1.821 |
1.924 |
1.842 |
weight after beating 100 times (W3) |
1.766 |
1.739 |
1.825 |
1.792 |
1.904 |
1.805 |
weight of dust filled in recessed portion (W2-W1) |
0.039 |
0.040 |
0.085 |
0.037 |
0.030 |
0.046 |
rate of removed dust (W2-W3)/(W2-W1) |
76.9% |
77.5% |
84.7% |
78.4% |
66.7% |
78.8% |
[Table 2]
|
gloves manufactured by present embodiment |
first time |
second time |
third time |
fourth time |
fifth time |
average |
experimenter |
A |
B |
c |
D |
E |
|
weight of specimen (W1) |
2.178 |
2.383 |
2.405 |
2.208 |
2.480 |
2.331 |
weight after rubbing 10 times (W2) |
2.190 |
2.392 |
2.414 |
2.221 |
2.484 |
2.340 |
weight after beating 100 times (W3) |
2.180 |
2.383 |
2.405 |
2.209 |
2.480 |
2.331 |
weight of dust filled in recessed portion (W2-W1) |
0.012 |
0.009 |
0.009 |
0.013 |
0.004 |
0.009 |
rate of removed dust (W2-W3)/(W2-W1) |
83.3% |
100.0% |
100.0% |
92.3% |
100.0% |
93.6% |
[0096] As can be also understood from Table 1, in the comparison specimens obtained from
the gloves manufactured by the powder adhesion method, the recessed portion was filled
with 0.046 g of dust in average per 25 cm
2 by rubbing of soil. On the other hand, in the glove according to the present embodiment,
as illustrated in Table 2, am amount of dust filled in the recessed portion can be
suppressed to 0.009 g in average per 25 cm
2. That is, an amount of dust generated in the present invention can be suppressed
to approximately 1/5 of an amount of dust generated in the powder adhesion method.
[0097] With reference to a rate of dust removed from the recessed portion, in case of the
glove that was manufactured by the powder adhesion method, only 78.8% of dust in average
was removed out of dust filled in the recessed portion even when a shake off operation
is performed. However, in case of the glove according to the present embodiment, 93.6%
of dust can be removed.
[0098] Further, surprisingly, among the experiment performed five times, different experimenters
confirmed a value of 100% that indicates the whole dust was substantially removed
three times. As a matter of course, when the specimens after the experiment was observed,
coloring of soil color was observed so that it was not the case that the whole dust
was removed in the accurate meaning of the term. However, dirt in the recessed portion
is minimally confirmed even with observation using naked eyes. Accordingly, Table
1 illustrates that in the present embodiment, dust is minimally filled in the recessed
portions compared to the gloves obtained by the powder adhesion method, and dust filled
in the recessed portion can be easily removed from the recessed portion compared to
the gloves obtained by the powder adhesion method.
[4. Test for confirming friction performance in a dry state]
[0099] Next, a test was performed so as to confirm friction performance in a dry state.
Gloves served in the test are four kinds of gloves consisting of gloves having no
recessed portions (gloves P), gloves manufactured by the powder adhesion method (gloves
Q), (isotropic) gloves according to the present embodiment where no anisotropy was
applied to the recessed portion (gloves R), and gloves according to the present embodiment
where anisotropy was applied to the recessed portion (gloves S).
[0100] The test was performed such that a palm portion of each glove on which the coating
film layer is formed was cut out by a size of a width of 5.5cm and a length of 7.5
cm, the cut-out specimen was laminated to a surface of a plate that was fixed at a
raised angle of 45 degrees, a flat-shaped metal circular columnar body having a weight
of 23 g, and having a height of 0.6cm and a diameter of 3.0cm was placed on a surface
of each specimen in a state where a bottom surface of the metal circular columnar
body opposedly faces the surface of each specimen, and friction performance in a dry
state was confirmed by measuring time until the circular columnar body slides down
along the surface of the specimen. The test was performed on the gloves S in two patterns
with respect to a case where the orientation direction is taken on the inclination
direction (glove S1) and the case where the orientation direction is taken on the
direction orthogonal to the inclination direction (glove S2). The result of the test
was illustrated in Table 3.
[Table 3]
|
time (second) |
gloves P |
2.12 |
gloves Q |
32.43 |
gloves R |
48.78 |
gloves S1 |
45.39 |
gloves S2 |
51.46 |
[0101] As can be also understood from Table 3, the time that the circular columnar body
slid down along the surface of the glove P on which recessed portions are not formed
was 2.12 seconds, and the time that the circular columnar body slid down along the
surface of the glove Q formed by a powder adhesion method was 32.43 seconds.
[0102] On the other hand, with respect to the gloves according to the present embodiment,
the time that the circular columnar body slid down on the surface of the glove R to
which anisotropy is not applied is 48.78 seconds that largely exceeds the corresponding
times in the case of the glove P and the glove Q. Accordingly, the glove R exhibited
an extremely excellent friction performance.
[0103] It must be particularly noted that, although the contact area of the glove R is smaller
than the contact area of the glove P, such large enhancement of friction performance
was observed. An analysis of such a phenomenon is expected by further extensive studies
of the inventors of the present invention. However, the inventors consider that a
suction cup effect described above was generated by the above-mentioned configuration.
[0104] Further, with respect to the glove according to the present embodiment, the time
that the circular columnar body slid down along the surface of the glove S to which
anisotropy was imparted was 45.39 seconds in case of the glove S1 where the inclination
direction is oriented in the gradient direction, and is 51.46 seconds in the case
of the glove S2 where the inclination direction is directed in the direction orthogonal
to the gradient direction. Accordingly, it was confirmed that anisotropy appeared
in the friction performance.
[0105] From these results, it was found that compared to the glove obtained by a powder
adhesion method, the glove according to the present embodiment is the glove that can
generate a larger friction force under a dry condition.
[5. Test for confirming friction performance in wet state]
[0106] Next, a test was performed so as to confirm friction performance in a wet state.
Gloves served in the test are, in the same manner as the above-mentioned [4. Test
for confirming friction performance in dry state], four kinds of gloves consisting
of gloves having no recessed portions (gloves P), gloves manufactured by the powder
adhesion method (gloves Q), (isotropic) gloves according to the present embodiment
where no anisotropy was applied to the recessed portion (gloves R), and gloves according
to the present embodiment where anisotropy was applied to the recessed portion (gloves
S) .
[0107] The test was performed such that a palm portion of each glove on which the coating
film layer is formed was cut out by a size of a width of 5.5 cm and a length of 7.5
cm, the cut-out specimen was laminated to a surface of a plate and was disposed at
a fixed raised angle of 45 degrees. The surface of the specimen was made wet by spraying
so that the specimen was brought into a wet state.
[0108] Next, a piece of ice cubicle produced by an ice making dish in a household use refrigerator
is placed on a surface of each specimen in a state where a flat surface of the ice
cubicle opposedly faces a flat surface, and friction performance in a wet state was
confirmed by measuring the time until the ice cubicle slid down along the surface
of the specimen. The test was performed on the gloves S in two patterns with respect
to a case where the orientation direction is taken on the inclination direction (glove
S1) and the case where the orientation direction is taken on the direction orthogonal
to the inclination direction (glove S2). The result of the test was illustrated in
Table 4.
[Table 4]
|
time (second) |
gloves P |
0.165 |
gloves Q |
0.204 |
gloves R |
did not fall |
gloves S1 |
did not fall |
gloves S2 |
did not fall |
[0109] As can be also understood from Table 4, the time that the ice cubicle slid down along
the surface of the glove P on which recessed portions are not formed was 0.165 seconds,
and the time that the ice cubicle slid down the surface of the glove Q formed by a
powder adhesion method was 0.204 seconds. Compared to the above-mentioned test in
a dry state, it was found that the gloves Q on which the recessed portions are formed
by the powder adhesion method is superior with respect to friction performance in
a wet state.
[0110] On the other hand, with respect to the glove R according to the present embodiment
where anisotropy is not imparted to the recessed portions and the gloves S1, S2 according
to the present embodiment where anisotropy is imparted to the recessed portions, very
surprisingly, the ice cubicle is not slid down at the same raised angle. Accordingly,
it was found that the gloves according to the present embodiment are gloves that have
extremely excellent wear performance also in a wet state compared to the gloves obtained
by a powder adhesion method.
[0111] When the inventors have studied on an angle at which an ice cubicle slide down by
further increasing the raised angle, a phenomenon that the gloves R did not slide
down even at an angle exceeding 90 degrees and did not fall even at an angle of 180
degrees in an upside down state was observed several times. In this manner, a phenomenon
that the ice cubicle did not slide down or fall even at an angle that exceeds 90 degrees
where there is no vertical resistance so that no friction force is generated was observed
and hence, it was considered that the above-mentioned suction cup effect was generated
between the coating film layer and the ice cubicle.
[0112] Further, also with respect to the gloves S1 and the gloves S2, in the same manner
as the gloves R, the ice cubicle did not slide down even at an angle that exceed 90
degrees and hence, it was considered that the above-described suction cup effect is
generated between the coating film layer and the ice cubicle. Still further, the inventors
increased the weight of the ice cubicle and confirmed a maximum angle by which the
ice cubicle can be held with respect to the gloves R, the gloves S1, and the gloves
S2. The gloves R could hold the ice cubicles by 53 degrees, the gloves S1 could hold
the ice cubicle by 48 degrees, and the gloves S2 could hold the ice cubicle by 57
degrees. Accordingly, it was confirmed anisotropy appeared in friction performance.
[0113] From these results, it was found that the gloves according to the present embodiment
are gloves that can generate a larger friction force even under a wet condition compared
to the glove obtained by a powder adhesion method.
[0114] As has been described above, according to the article that includes the coating
film layer that imparts an anti-slipping effect according to the embodiment, the article
is an article that includes the coating film layer which covers the surface of the
article and on which the plurality of recessed portions are formed so as to impart
an anti-slipping effect, and the plurality of recessed portions are formed of: the
plurality of hemispherical recessed portions having an approximately circular shape
as viewed in a plan view; and the plurality of diaphragm provided recessed portions
formed such that two or more hemispherical recessed portions are connected to each
other in a partially overlapping manner and the connection boundary between the recessed
portions is partitioned by a diaphragm. Accordingly, it is possible to provide the
article where, compared to an article that has an anti-slipping effect obtained by
a powder adhesion method, dust is minimally filled in the recessed portion for anti-slipping
and, further, a larger friction force can be generated.
[0115] Further, the gloves according to the present embodiment are the gloves where the
plurality of recessed portions are formed on the coating film layer that covers the
surface of the gloves, wherein the plurality of recessed portions are formed of: the
plurality of hemispherical recessed portions having an approximately circular shape
as viewed in a plan view; and the plurality of diaphragm provided recessed portions
formed such that two or more hemispherical recessed portions are connected to each
other in a partially overlapping manner and the connection boundary between the recessed
portions is partitioned by a diaphragm. Accordingly, it is possible to provide the
gloves where, compared to the gloves that have an anti-slipping effect obtained by
a powder adhesion method, dust is minimally filled in in the recessed portion, further,
a larger friction force can be generated.
[0116] Finally, the description of the above-mentioned respective embodiments exemplifies
one example of the present invention, and the present invention is not limited by
the above-mentioned respective embodiments. Accordingly, although other embodiments
may be considered besides the above-mentioned embodiment, it is needless to say that
various modifications are conceivable corresponding to designing and the like without
departing from the technical concept of the present invention.
List of Reference Signs