U.S. patent application number 09/833610 was filed with the patent office on 2001-12-20 for article made of a flexible material.
This patent application is currently assigned to SEMPERIT AKTIENGESELLSCHAFT HOLDING. Invention is credited to Schaller, Raimund.
Application Number | 20010053421 09/833610 |
Document ID | / |
Family ID | 3517354 |
Filed Date | 2001-12-20 |
United States Patent
Application |
20010053421 |
Kind Code |
A1 |
Schaller, Raimund |
December 20, 2001 |
Article made of a flexible material
Abstract
The invention relates to an article, in particular a glove, a
condom, or the like, which is comprised of a flexible rubber and/or
plastic, is embodied having at least one section of the surface
intended contact or rest against human skin, which article is
provided with a slip coating in a section of the surface. This slip
coating is comprised of a polymeric material and at least in
sections, has repeating shape deviations of the surface that are
recessed in relation to a raised, net-like structure. The ratio of
the average spacings between the shape deviations to their depth in
relation to the raised, net-like structure is between 500:1 and 5:1
and the average roughness depth is between 0.5 and 100 .mu.m,
preferably between 1 and 40 .mu.m.
Inventors: |
Schaller, Raimund;
(Wimpassing, AT) |
Correspondence
Address: |
GREENBLUM & BERNSTEIN, P.L.C.
1941 ROLAND CLARKE PLACE
RESTON
VA
20191
US
|
Assignee: |
SEMPERIT AKTIENGESELLSCHAFT
HOLDING
Vienna
AT
|
Family ID: |
3517354 |
Appl. No.: |
09/833610 |
Filed: |
April 13, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09833610 |
Apr 13, 2001 |
|
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08927285 |
Sep 11, 1997 |
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Current U.S.
Class: |
427/557 ;
427/385.5; 427/407.1; 427/430.1; 428/36.8 |
Current CPC
Class: |
Y10T 428/24521 20150115;
A41D 19/0058 20130101; A61B 42/00 20160201; Y10T 428/24331
20150115; Y10T 428/1352 20150115; Y10T 428/24554 20150115; Y10T
428/1386 20150115; Y10T 428/24504 20150115; Y10T 428/24479
20150115; Y10T 428/24975 20150115 |
Class at
Publication: |
427/557 ;
428/36.8; 427/407.1; 427/385.5; 427/430.1 |
International
Class: |
B05D 003/06; B32B
001/02; B05D 003/02; B05D 001/36; B05D 001/18 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 12, 1996 |
AT |
1620/96 |
Claims
1. An article made of a flexible rubber or plastic, which is
embodied in at least one section of the surface intended to contact
or rest against human skin, in particular a glove, a condom, or the
like, which is provided with a slip coating in a section of the
surface, characterized in that this slip coating (9) is comprised
of a polymeric material (10) and has at least one partial area (65
to 68) having repeating shape deviations (14) of the surface (12)
that are recessed in relation to a raised, net-like structure,
wherein the ratio of the average spacings (15, 16) between the
shape deviations (19, 20) to their depth (17) in relation to the
raised, net-like structure is between 500:1 and 5:1 and the average
roughness depth is between 0.5 and 100 .mu.m, preferably between 1
and 40 .mu.m.
2. The article according to claim 1, characterized in that between
50 and 90%, preferably between 60 and 80% of the partial area is
disposed as recessed by means of shape deviations (19, 20).
3. The article according to claim 1 or 2, characterized in that at
least 50% of the shape deviations (19, 20) in the top view of the
slip coating (9) are encompassed on all sides by the net-like
structure (23).
4. The article according to one or more of the preceding claims,
characterized in that the material (10) of the slip coating (9) is
comprised of at least one natural and/or synthetic latex.
5. The article according to one or more of the preceding claims,
characterized in that the material (10) of the slip coating (9) is
comprised of a latex mixture and is fixed to the surface (12) of
the carrier layer (3).
6. The article according to one or more of the preceding claims,
characterized in that the material (10) is comprised of a
polyurethane.
7. The article according to one or more of the preceding claims,
characterized in that the material (10) is comprised of
polyacrylates and/or polymethacrylates and/or polysiloxanes or
other comparable products.
8. The article according to one or more of the preceding claims,
characterized in that the slip coating is comprised of 0 to 30 wt.
% polyurethane, 1 to 40 wt. % polyacrylate, 1 to 20 wt. %
polysiloxane, and 0 to 40 wt. % filler.
9. The article according to one or more of the preceding claims,
characterized in that the filler is comprised of pulverized or
powdered materials such as chalk, lime, cornstarch, silicon
dioxide, and/or gypsum.
10. The article according to one or more of the preceding claims,
characterized in that the polymeric material (10) contains water
absorbing groups.
11. The article according to one or more of the preceding claims,
characterized in that the polymeric material (10) is comprised of
intensely hydrophilic groups, for example acrylic acid and/or
methacrylic acid and/or an acrylate and/or a methacrylate.
12. The article according to one or more of the preceding claims,
characterized in that the material (10) has a high surface adhesion
and is preferably not cross-linked.
13. The article according to one or more of the preceding claims,
characterized in that a silicone is deposited onto the regions of
the slip coating (9), which are provided with a roughening.
14. The article according to one or more of the preceding claims,
characterized in that a silicone is deposited onto the slip coating
(9).
15. The article according to one or more of the preceding claims,
characterized in that the quantity of the silicone, at least on the
surface of the sections (7, 18), is between 0.05 and 3 g/m.sup.2,
preferably 0.25 g/m.sup.2.
16. The article according to one or more of the preceding claims,
characterized in that the slip coating or coatings (9) are
deposited on the inner surface (12) of the sleeve-like carrier
layer (3).
17. The article according to one or more of the preceding claims,
characterized in that the slip coating or coatings (9) is or are
deposited on the outer surface (12) of the sleeve-like carrier
layer (3).
18. The article according to one or more of the preceding claims,
characterized in that the average roughness depth is lower in
sections having lower relative movement between the article (1) and
the skin of the user.
19. The article according to one or more of the preceding claims,
characterized in that at least one layer of the carrier layer (3)
is comprised of a latex product (2), which contains a polymer (5),
e.g. a natural and/or synthetic latex.
20. The article according to one or more of the preceding claims,
characterized in that the slip coating (9) is disposed on a carrier
layer (3) comprised of at least one layer, which is preferably
slightly cross-linked.
21. The article according to one or more of the preceding claims,
characterized in that the latex product (2) is
pre-cross-linked.
22. The article according to one or more of the preceding claims,
characterized in that the carrier layer (3) is comprised of an
aqueous solution of a coagulant, which contains calcium nitrate,
polyethylene glycol, and a water soluble silicone or chalk, and a
pre-cross-linked natural latex mixture.
23. The article according to one or more of the preceding claims,
characterized in that the carrier layer (3) in particular contains
a pre-cross-linked synthetic latex, e.g. chloroprene latex, NBR
latex, X-NBR latex, or SBR latex.
24. The article according to one or more of the preceding claims,
characterized in that the carrier layer (3) is embodied as
sleeve-like and has an outer and an inner surface (12).
25. The article according to one or more of the preceding claims,
characterized in that at least one section (7, 18) is disposed on
the inner surface (12) of the article (1), particularly of the
glove (4).
26. The article according to one or more of the preceding claims,
characterized in that at least one section (7, 18) is disposed on
the outer surface (12) of the article (1), particularly of the
glove (4).
27. The article according to one or more of the preceding claims,
characterized in that the carrier layer (3) is chlorinated on its
surface.
28. The article according to one or more of the preceding claims,
characterized in that raised edge regions of the surface
deformations built up by the chlorination protrude above the
neighboring surface zones by a height of 0.5 to 10 .mu.m,
preferably .ltoreq.1 .mu.m.
29. The article according to one or more of the preceding claims,
characterized in that the inner surface (12) of the slip coating
(9) of the article (1) is provided with a coating of silicone
and/or is treated with chlorine.
30. The article according to one or more of the preceding claims,
characterized in that this article is embodied as a rubber
glove.
31. The article according to one or more of the preceding claims,
characterized in that this article is embodied as a medical
glove.
32. The article according to one or more of the preceding claims,
characterized in that the slip coating (9) is at least deposited on
the inner surface (12) of the rubber or medical glove.
33. The article according to one or more of the preceding claims,
characterized in that only a section (65 to 68) of the slip coating
(9) is provided with shape deviations (19, 20) in the region of its
surface.
34. The article according to one or more of the preceding claims,
characterized in that the surfaces of the rubber or medical glove
that are oriented toward the palm of the hand and the back of the
hand are provided with a slip coating (9) and if need be, at least
sections (65 to 68) of this slip coating (9) are provided with the
shape deviations (19, 20) in their surfaces.
35. The article according to one or more of the preceding claims,
characterized in that an outer surface (12) of the rubber or latex
glove is provided with shape deviations (14), wherein the ratio of
the spacings (15, 16) of the shape deviations (14) to their depth
(17) is between 100:1 and 5:1 and the average roughness depth is
between 0.5 and 100 .mu.m, preferably between 1 and 40 .mu.m.
36. The article according to one or more of the preceding claims,
characterized in that sections (7, 18) of the outer surface (12) of
the rubber or medical gloves are provided with a slip coating (9)
and are provided with shape deviations (19, 20) in their surface,
at least in the region of the slip coating (9).
37. A process for producing a flexible article, in particular a
glove, a condom, or the like, in which a carrier layer is made of
plastic and/or rubber and in sections of its surface or in at least
one section of its surface that has a slip coating, is provided
with a roughness in the region of its surface remote from the
carrier layer, in particular a process for producing an article
according to one of the preceding claims, characterized in that the
slip coating is applied to the carrier layer by means of dipping
and is dried immediately afterward, preferably for 10 to 600 sec.
by means of hot air, whereupon the slip coating is treated with
water at a temperature between 40 and 100.degree. C., preferably
between 60 and 80.degree. C., or is rinsed with the hot water so
that afterwards, the water content of the slip coating is reduced
by approx. 40 to 70%, preferably 50 to 60%.
38. The process according to claim 35, characterized in that
immediately following the draining period after the rinsing of the
article with the hot water, the article is exposed to an infrared
radiation.
39. The process according to claim 35 or 36, characterized in that
the emitting bodies for giving off the infrared radiation, e.g.
stove tiles, have a temperature between 350 and 700.degree. C.
40. The process according to one or more of claims 35 to 37,
characterized in that the duration of the exposure to infrared
radiation is between 1 and 5 minutes.
41. The process according to one or more of claims 35 to 38,
characterized in that the draining period between the rinsing of
the article with the hot water and the application of the infrared
radiation is between 10 and 180 seconds, preferably between 20 and
50 seconds.
42. The process according to one or more of claims 35 to 39,
characterized in that the article is acted upon by hot air during
the draining period.
43. The process according to one or more of claims 35 to 40,
characterized in that in the drying of the coagulation solution of
the latex product and/or the slip coating, which is preferably
carried out with hot air, this material is converted on its surface
from the liquid state into the gelatinous or solid state.
44. The process according to one or more of claims 35 to 41,
characterized in that the drying of the surface of the latex
product and/or the slip coating is carried out at a temperature
from 70 to 140.degree. C., preferably 90 to 110.degree. C.
45. The process according to one or more of claims 35 to 42,
characterized in that the drying process of the latex product and
the slip coating takes between 10 and 80 seconds, preferably
between 15 and 60 seconds.
46. The process according to one or more of claims 35 to 43,
characterized in that the temperature of the hot water for rinsing
the slip coating is between 40 and 95.degree. C., preferably
between 70 and 90.degree. C. and the treatment lasts for 15 sec. to
8 min., preferably 30 sec. to 4 min..
47. The process according to one or more of claims 35 to 44,
characterized in that the slip coating is comprised of a dispersion
that contains at least one polymeric material.
48. The process according to one or more of claims 35 to 45,
characterized in that the dispersion is comprised of a mixture
containing 0 to 30 wt. % of a polyurethane dispersion, 1 to 40 wt.
% of a polyacrylate dispersion, 1 to 20 wt. % of a polysiloxane
dispersion, and 0 to 10 wt. % filler, and the remaining portion is
comprised of water.
49. The process according to one or more of claims 35 to 47,
characterized in that the filler is comprised of powdered or
pulverized materials such as chalk, lime, cornstarch, silicon
dioxide, and/or gypsum.
50. The process according to one or more of claims 35 to 46,
characterized in that the viscosity of the dispersion of the slip
coating is between 5 and 30 mPa.s, preferably 7 to 11 mPa.s.
51. The process according to one or more of claims 35 to 48,
characterized in that the roughness is formed by the form surfaces
on the carrier layer.
52. The process according to one or more of claims 35 to 49,
characterized in that the recesses are produced by the pressing-in
of fine beads or by sandblasting.
53. The process according to one or more of claims 3 5 to 5 0,
characterized in that a slip coating, preferably a silicone, is
deposited onto the roughened surfaces of the sections.
54. The process according to one or more of claims 35 to 51,
characterized in that the shape deviation of the outer surface of
the glove, in particular of a rubber or latex glove, as a result of
the depositing of the carrier material onto a form whose surface
has shape deviations in which the ratio of the spacings of the
shape deviation to their depth is between 100:1 and 5:1 and the
average roughness depth is between 0.5 and 100 .mu.m, preferably
between 1 and 40 .mu.m.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of application Ser. No.
08/927,285, filed Sep. 11, 1997. The entire disclosure of
application Ser. No. 08/927,285 is considered as being part of the
disclosure of this application, and the entire disclosure of
application Ser. No. 08/927,285 is expressly incorporated by
reference herein in its entirety.
[0002] The present application claims priority under 35 U.S.C.
.sctn. 119 of Austrian Patent Application No. 1620/96 filed Sep.
12, 1996, the disclosure of which is expressly incorporated by
reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The invention describes an article made of a flexible rubber
and/or plastic as well as a process for making this article.
[0005] Many flexible articles that are untreated on the surface,
particularly those made of plastic and rubber, have a relatively
high degree of friction resistance in relation to human skin. This
is why untreated rubber gloves, for example, are almost impossible
to put on. In order to make it easier to put these gloves on, glove
powder (e.g. starch powder, talcum, etc.) is conventionally
deposited as a parting compound on the inside of the glove. The use
of powder, though, is particularly problematic in the medical field
because residual powder can lead to granule formation if it gets
into open wounds. Another important application field for
powder-free products is the electronics industry.
[0006] A classic method for making articles of rubber and in
particular, gloves that are slippery in relation to human skin
without the use of powder, involves surface chlorination. In this
connection, the article is treated with aqueous, chlorine
gas-containing mediums and is then washed. Primarily, this produces
a favorable slipperiness in relation to dry human skin, but this
surface chlorination synthetically alters the polymer structure and
thus produces a distinct diminishing of the physical and chemical
properties of the article (strength, tear elasticity, water
swelling, storability, etc.). However, surface-treated gloves of
this kind are also usually difficult to put on with wet hands.
[0007] Coating with hydrogels represents an alternative surface
treatment. Some hydrogels of this kind have been known for a long
time. For example, these are polyurethane, polyvinylpyrrolidone,
polyhydroxyethylacrylate or polyhydroxymethacrylate,
polyhydroxypropylacrylate or polyhydroxypropylmethacrylate, and are
copolymers with one another or with acrylic acid or methacrylic
acid, acrylic ester or methacrylic ester, or vinylpyridine.
[0008] A coating of this kind has been disclosed by U.S. Pat. No.
3,813,695-A, which describes a dipped rubber glove that is coated
on the inside with a hydrogel polymer such as polyvinylpyrrolidone,
polyhydroxyethacrylate or polyhydroxymethacrylate,
polyhydroxypropylacrylate or polyhydroxypropylmethacrylate, and
copolymers of these with one another or with acrylic acid or
methacrylic acid. The preferred hydrogel polymer is a copolymer of
2-hydroxyethylmethacrylate with methacrylic acid or with
2-ethylhexylacrylate or a ternary copolymer of
2-hydroxyethylmethacrylate- , methacrylic acid and
2-ethylhexylacrylate.
[0009] A known manufacturing process is disclosed by U.S. Pat. No.
4,482,577-A. This patent discloses the coating of a flexible,
vulcanized surgical glove with a hydrophilic polymer, by means of
which the depositing of powder on the inside of the glove can be
omitted. The copolymer used in this instance is comprised of a
mixture of 2-hydroxyethylmethacrylate and 2-ethylhexylacrylate.
[0010] Another process according to U.S. Pat. No. 4,100,309-A
discloses the depositing of a slippery coating comprised of a
polyurethane-polyvinylpyrrolidone complex. Normally with these
products or processes, the hydropolymer is deposited on the product
together with a hardener in dissolved form, then the solvent is
removed by drying, wherein the polymer layer is hardened, thus
forming a hydrogel coating.
[0011] Other known embodiments disclose the use of vinylidene
halogenide lattices or vinyl halogenide lattices for producing a
slip coating on rubber articles, e.g. U.S. Pat. No. 5,069,965-A,
where the slippery quality is mostly achieved by means of polymers
that contain chlorine.
[0012] DE 26 28 059-C and U.S. Pat. No. 4,082,862 disclose the use
of diverse latex mixtures for producing a slip coating. In
particular, mixtures comprised of at least two latex types are used
in this connection, wherein a latex type with a high elasticity is
used as a bonding agent and a latex type with a high degree of
hardness or low elasticity is used to obtain a sufficient
slipperiness. These recipes are usually more or less favorable
compromises between slipperiness, sufficient film flexibility, and
adhesion of the film to the rubber product. In particular, with the
use of the slip coating in very flexible, highly elastic rubber
articles, there are often problems in this connection to the effect
that the slip coatings used either begin to detach from the
foundation when stretched or do not have a satisfactory
slipperiness in actual use.
[0013] In the process according to EP 0 681 912-A2, the slip
coating is comprised of a copolymer latex, which is fixed to the
carrier layer with the aid of a coagulation step. The latex is
comprised of a copolymer that contains a significant portion of
hydrophilic monomer components.
[0014] U.S. Pat. No. 4,143,109-A describes another method for
producing slipperiness in relation to skin with powder-free medical
gloves made of natural latex. In this instance, bonded cornstarch
particles or polyethylene particles are deposited in a carrier
layer, wherein the carrier layer is thinner than the diameter of
the particles and the particles protrude from the surface. The
powder particles bonded in this manner produce a sufficient
slipperiness of the glove interior. This embodiment for achieving
slipperiness in relation to skin has problems when the product is
stretched to a great degree, which is inevitable when putting on
latex medical gloves: The surface-bonded particles detach easily
and the powder-free nature is no longer assured.
[0015] All of the above-described powder-free articles can only be
produced with satisfactory product properties only under the most
precise adherence to the affiliated process requirements and
material recipes. While a favorable slipperiness of the surfaces in
relation to dry skin is usually achieved with ease, very often
there are difficulties in the reproducibility with regard to wet
slipperiness. In particular with thin-walled flexible articles,
which must have favorable slipperiness even when stretched to a
great degree, it often takes years of high-precision optimization
on the part of the manufacturer, who usually has to adopt
compromises with regard to diverse product properties. Despite the
use of polymeric slip coating hydrogels, the surface is frequently
lightly chlorinated. Other manufacturers, in spite of the polymer
slip coatings, use additional small quantities of glove powder.
Still other producers see themselves as confronted with constant
fluctuations with regard to the wet slipperiness of their
products.
SUMMARY OF THE INVENTION
[0016] The object of the current invention is to produce articles
made of plastic and/or rubber, which have a favorable slipperiness
in relation to human skin, particularly wet skin, and to develop a
process which can be easily reproduced.
[0017] This is attained by an article made of a flexible rubber or
plastic, such as a glove, a condom, or the like, which includes a
surface section that contacts or rests against human skin, and
which is provided with a slip coating in a section of the surface
that is comprised of a polymeric material and has at least a
partial area having repeating surface shape deviations that are
recessed in relation to a raised, net-like structure, where the
ratio of the average spacings between the shape deviations to their
depth, in relation to the raised, net-like structure, is between
500:1 and 5:1 and the average roughness depth is between 0.5 and
100 .mu.m, preferably between 1 and 40 .mu.m. In this connection,
it is advantageous that the flexible products with the raised net
structure and the recessed faces and the slightly roughened surface
constituted by this have a significantly better slipperiness than
smooth slip coatings, primarily in relation to wet human skin. This
is particularly true for wet slipperiness, which is often difficult
to achieve. A further advantage of the current invention is that
avoiding occlusive skin contact makes wearing the articles more
comfortable, improves their ability to be taken off, and if
necessary, significantly improves their absorption of sweat. It is
also significant that as a result of the rigorous reduction of the
contact area between skin and polymer, in many cases, a
significantly improved skin compatibility can be expected. In
addition, allergic reactions are reduced and there is no confined
feeling after the product is put on. It is advantageous that the
roughened surface morphology according to the invention can be
produced without additional mechanical or chemical treatment, such
as embossing or chlorinating processes, and can also be produced,
for example without the addition of a parting compound, e.g. powder
or silicone. As a result, a favorable slipperiness can also be
achieved using less optimal slip coating polymers. When a roughened
surface structure is maintained, a favorable slipperiness can be
achieved in both the wet and dry states.
[0018] According to another aspect of the invention, the flexible
article is characterized in that between 50 and 90%, preferably
between 60 and 80%, of the partial area's repeating surface shape
deviations are recessed. This is also advantageous since the wealth
of micro-cavities formed in this-manner can considerably reduce the
friction potential or the contact area between the article and
human skin.
[0019] According to another aspect of the invention, the flexible
article is characterized in that at least 50% of the shape
deviations, according to a top view of the slip coating, are
encompassed on all sides by the net-like structure. This assures
that a large part of the slip coating is kept at a distance from
the skin by the net-like structure, even when the article is being
worn, in which state the article is slightly stretched or drawn
taut, so that in spite of the roughening, on the one hand, the user
does not get the feeling that the article is chafing his skin and
on the other hand, the movement of the hand, for example of the
fingers, is not hindered since the slip coating or the partial
surface of the slip coating does not stick to the wet skin.
[0020] The flexible article gives the skin a comfortable feeling if
the slip coating comprises at least one natural and/or synthetic
latex, or if the slip coating comprises a latex mixture and is
fixed to the surface of the carrier layer.
[0021] Favorable properties for the slip coating and a firm
adhesion of it to the carrier layer are achieved according to
another aspect of the invention if the slip coating material
comprises polyurethane.
[0022] A favorable skin compatibility for articles is achieved
according to another aspect of the invention where the slip coating
material comprises polyacrylates and/or polymethacrylates and/or
polysiloxanes or other comparable products.
[0023] According to yet another aspect of the invention, surface
roughness that is caused by the corresponding secondary treatment
through chemical and/or physical reactions can be easily produced
where the slip coating comprises 0 to 30 wt. % polyurethane, 1 to
40 wt. % polyacrylate, 1 to 20 wt. % polysiloxane, and 0 to 40 wt.
% filler. Such surface roughness may be produced where the filler
material comprises pulverized or powdered materials such as chalk,
lime, cornstarch, silicon dioxide, and/or gypsum.
[0024] According to yet another aspect of the current invention,
the use of a polymeric material in a slip coating that contains
water absorbing groups makes the flexible articles particularly
comfortable properties for people who perspire a lot.
[0025] According to still another aspect of the invention,
perspiration retention on the surface of the skin can be better
controlled in the region of the roughened surfaces in the sections,
since the glove can absorb a higher quantity of moisture, where the
polymeric material of the slip coating comprises intensely
hydrophilic groups, for example acrylic acid and/or methacrylic
acid and/or an acrylate and/or a methacrylate.
[0026] According to another aspect of the invention, a favorable
connection with the slip coating in the sections can be achieved
where the slip coating material has high surface adhesion and
preferably is not cross-linked.
[0027] According to yet another aspect of the invention, the wet
slipperiness of the articles can be additionally improved where
silicone is deposited onto the regions of the slip coating which
have surface roughening.
[0028] According to still another aspect of the invention, uniform
slip behavior of the article is achieved where silicone is
deposited onto regions of the slip coating.
[0029] According to yet another aspect of the invention, a very
thin coating of silicone that increases slipperiness while at the
same time preventing adhesion of the recesses, is achieved where
the silicone on the surface sections of the slip coating is between
0.05 and 3 g/m.sup.2, preferably 0.25 g/m.sup.2.
[0030] According to another aspect of the invention, a slip coating
or coatings is or are deposited on the inner surface of a
sleeve-like carrier layer. According to yet another aspect of the
invention, the slip coating is or are deposited on the outer
surface of the sleeve-like carrier layer. According to still
another aspect of the invention, the average roughness depth is
lower in sections having lower relative movement between the
flexible article and the skin of the user. These features provide
slipperiness and slip properties as well as a roughness that
corresponds, for example, to the grasping of tools or articles used
in the assembly field.
[0031] According to another aspect of the invention, it is
advantageous where at least one layer of the carrier layer is
comprised of a latex product, which contains a polymer, e.g. a
natural and/or synthetic latex since it can be used to produce
extremely thin and extremely elastic articles that are also very
resilient.
[0032] According to yet another aspect of the invention, the
quality of the flexible articles can be considerably improved where
the slip coating is provided on a carrier layer comprised of at
least one layer, which preferably is slightly cross-linked.
According to still another aspect of the invention, the latex of
the carrier layer is pre-cross-linked.
[0033] According to yet another aspect of the invention, the
article has a high degree of elasticity and suppleness where the
carrier layer comprises an aqueous solution of a coagulant, which
contains calcium nitrate, polyethylene glycol, a water soluble
silicone or chalk, and a pre-cross-linked natural latex
mixture.
[0034] According to another aspect of the invention, to make the
carrier layer resistant the carrier layer contains a
pre-cross-linked synthetic latex, e.g. chloroprene latex, NBR
latex, X-NBR latex, or SBR latex.
[0035] According to yet another aspect of the invention, the
carrier layer is embodied in a sleeve-like article having an outer
surface and an inner surface which can be used to adapt the
roughness of the individual surfaces or sections to the various
intended uses of the article. According to another aspect of the
invention, at least one surface section is disposed on the inner
surface of the article, particularly of the glove, to achieve the
intended roughness. Moreover, according to another aspect of the
invention, at least one surface section is disposed on the outer
surface of an article, particularly of a glove, which achieves the
intended roughness.
[0036] According to another aspect of the invention, chlorinating
the carrier layer on its surface further improves the effect of the
roughness in the region of the carrier layer, or it produces at
least a partial improvement of the slip properties in those regions
where there is no roughening. Further, the raised edge regions of
the chlorinated surface deformations caused by the chlorination may
protrude above the neighboring surface zones by a height of 0.5 to
10 .mu.m, preferably less than 1 .mu.m.
[0037] According to another aspect of the invention, the inner
surface of the slip coating of the article is provided with at
least one of a coating of silicone and a treatment with chlorine,
to cause preferred grading of the roughness and of the slipperiness
of the flexible article in its various regions.
[0038] According to yet another aspect of the invention, the
flexible article may be a rubber glove. According to yet another
aspect of the invention, the article may be a medical glove.
[0039] Universal adaptations of adhesion, grip security, or
slipperiness and wet slipperiness are achieved, according to
another aspect of the invention, where the slip coating is
deposited on the inner surface of the rubber glove or the medical
glove. Further, only a section of the slip coating may have shape
deviations in the region of its surface. Moreover, the surfaces of
the rubber gloves or the medical gloves that are oriented toward
the palm of the hand, or the back of the hand, may be provided with
a slip coating, and if need be, at least sections of this slip
coating may be provided with the surface shape deviations. Further,
an outer surface of the rubber or latex glove may be provided with
shape deviations where the ratio of the spacings of adjacent shape
deviations to their depth is between 100:1 and 5:1, and their
average roughness depth is between 0.5 and 100 .mu.m, and
preferably between 1 and 40 .mu.m. Moreover, sections of the outer
surface of the rubber glove or the medical gloves according to the
invention may be provided with a slip coating and have surface
shape deviations, at least in the region of the slip coating.
[0040] The invention also includes a process for manufacturing a
flexible article, in particular a glove, where a carrier layer is
made of plastic and/or rubber, and at least one section of its
surface that has a slip coating, which is provided with a roughness
in the region of its surface remote from the carrier layer.
Moreover, where the slip coating is applied to the carrier layer by
means of dipping and is dried immediately afterward, preferably for
10 to 600 sec. by means of hot air, and then the slip coating is
treated with water at a temperature between 40 and 100.degree. C.,
preferably between 60 and 80.degree. C., or is rinsed with the hot
water so that afterwards, the water content of the slip coating is
reduced by approx. 40 to 70%, preferably 50 to 60%, such that a
slip coating in a section of the surface is comprised of a
polymeric material with at least a partial area having repeating
surface shape deviations that are recessed in relation to a raised,
net-like structure. The individual, succeeding measures produce a
distortion in the surface of the slip coating and therefore produce
the sinking of the recesses, which represent the deviations in
shape, in relation to the intermediary pieces of the net-like
structure that remain at the original height, by means of which a
higher wearing comfort is produced by the higher elasticity,
primarily when moving the fingers, and the slipperiness of the
article is additionally improved in relation to human skin, above
all when it is wet. Furthermore, the roughenings produced during
the manufacturing process do not absolutely require additional
treatment such as a subsequent chlorination or the application of a
parting compound or the like.
[0041] According to another aspect of the invention, the flexible
article is exposed to infrared radiation immediately following the
draining period after the rinsing of the article with the hot
water, and this permits the roughened structure that appears during
the course of the drying process on the top side of the slip face
or the net-like structure of intermediary pieces, which protrude by
the measure of between 0.5 .mu.m and 100 .mu.m above the deviations
in shape that are sunk with the dehydration, to produce a support
grid that is supported on the surface of the skin and reduces the
contact area between the skin and the article, without producing an
uncomfortable scratchy effect that is felt when the surface is too
rough.
[0042] The high temperature of the emitting body that gives off the
infrared radiation, such as stove tiles, which may have
temperatures of between 350.degree. C. and 700.degree. C., permits
rapid stabilization of the surface deformations without causing the
net-like structure to be reformed.
[0043] According to another aspect of the invention, by exposing
the article to infrared radiation for between 1 and 5 minutes, the
chemical reaction is finished in the entire article, both in the
carrier layer and in the slip coating, and a secure connection is
produced between these layers.
[0044] According to yet another aspect of the invention, the sunken
shape deviations produced by the dehydration are prevented from
leveling out again as a result of a uniform distribution of for
example, the gelatinous fluid over the coating before they are
permanently fixed, where the draining period between the rinsing of
the article with the hot water and the application of infrared
radiation is between 10 and 180 seconds, preferably between 20 and
50 seconds. The flexible may also be subjected to hot air during
the draining period.
[0045] A favorable adhesion between the carrier layer and the slip
coating is achieved according to yet another aspect of the
invention, when during the drying of the coagulation solution of
the latex product and/or the slip coating, which is preferably
carried out with hot air, the surface of the latex product and/or
the slip coating is converted from a liquid state into the
gelatinous or solid state. Such adhesion also may be achieved when
the drying of the surface of the latex product and/or the slip
coating is carried out at a temperature from 70 to 140.degree. C.,
preferably at a temperature from 90 to 110.degree. C. Further, the
drying process of the latex product and the slip coating may take
between 10 and 80 seconds, preferably between 15 and 60
seconds.
[0046] According to another aspect of the invention, rapid
dehydration of the slip coating accompanied by a more pronounced
sinking of the shape deviation in relation to the net-like
structure is achieved where the temperature of the hot water for
rinsing the slip coating is between 40 and 95.degree. C.,
preferably between 70 and 90.degree. C., and the treatment lasts
for 15 sec. to 8 min., preferably 30 sec. to 4 min.
[0047] According to still another aspect of the invention, the use
of a slip coating comprised of a dispersion containing at least one
polymeric material, increases skin compatibility and simplifies the
manufacture of shape deviations that are sunken in relation to the
net-like structure.
[0048] According to another aspect of the invention, a composition
of dispersion is comprised of a mixture containing 0 to 30 wt. % of
a polyurethane dispersion, 1 to 40 wt. % of a polyacrylate
dispersion, 1 to 20 wt. % of a polysiloxane dispersion, and 0 to 10
wt. % filler, and the remaining portion water, encourages the
formation of the net-like structure and the recesses that
constitute the shape deviations. Moreover, the filler may comprise
powdered or pulverized materials such as chalk, lime, cornstarch,
silicon dioxide, and/or gypsum. Further, the viscosity of the
dispersion of the slip coating may be between 5 and 30 mPa.'s,
preferably 7 to 11 mPa.'s.
[0049] According to still another aspect of the invention, the
roughness is created by the form surfaces on the carrier layer,
which can improve the production of roughness in the carrier layer
and/or the slip coating or in sections of them. According to
another aspect of the invention, the recesses are produced by the
pressing-in of fine beads or by sandblasting can improve the
roughness of the carrier layer and/or the slip coating, or in
sections of them.
[0050] According to still another aspect of the invention, a slip
coating, preferably comprising silicone, is deposited onto the
roughened surfaces of the flexible article.
[0051] Finally, according to yet another aspect of the invention,
the shape deviation of the outer surface of the glove, in
particular of a rubber or latex glove, as a result of the
depositing of the carrier material onto a form whose surface has
shape deviations in which the ratio of the spacings of adjacent
shape deviations to their depth is between 100:1 and 5:1, and the
average roughness depth is between 0.5 and 100 .mu.m, preferably
between 1 and 40 .mu.m, improves the handling of tools or machine
parts or components, particularly if these gloves are used in the
assembly of electronic components or clean room parts.
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] The invention is explained in detail below in conjunction
with exemplary embodiments shown in the drawings.
[0053] FIG. 1 is a sectional, simplified schematic diagram of a
part of an article according to the invention, with a slip face and
a corresponding roughness;
[0054] FIG. 2 is a partial section through a top view of an article
according to the invention, in the form of a glove;
[0055] FIG. 3 is a simplified schematic representation of an end
view of the article according to FIG. 2, cut along line III-III in
FIG. 2;
[0056] FIG. 4 is a simplified schematic representation of a part of
the course of the process according to the invention for
manufacturing an article;
[0057] FIG. 5 is a simplified schematic representation of another
part of the course of the process for manufacturing an article;
[0058] FIG. 6 is simplified schematic representation of a sectional
end view of a porcelain form with the layers deposited on it for
manufacturing an article according to the invention constituted by
a glove;
[0059] FIG. 7 is a top view of the surface of the slip coating of
an article according to the invention, in a depiction that has been
considerably enlarged by an electron microscope.
DETAILED DESCRIPTION OF THE INVENTION
[0060] By way of introduction, it should be emphasized that in the
different exemplary embodiments described, identical parts are
provided with the same reference numerals or the same component
labels, wherein the disclosures contained in the entire
specification can by analogy be transferred to identical parts with
the same reference numerals or the same component labels.
Furthermore, individual features from the different exemplary
embodiments shown can also represent embodiments according to the
invention that are independent in and of themselves.
[0061] FIG. 1 shows a flexible article 1 according to the
invention, which is preferably embodied as a latex product 2. This
product is comprised of a carrier layer 3, which, as is usually the
case in the manufacture of thin-walled rubber and plastic articles,
is preferably formed by means of a multiple dipping process. These
articles 1 can be gloves 4, for example medical, surgical, and
experimental gloves, catheters, condoms, finger cots, bathing caps,
swim fins, or protective gloves for work in clean room areas.
Thin-walled articles, in particular elastic articles made of rubber
and/or plastic such as the glove 4, for example, are preferably
obtained by dipping a form into a latex product 2, wherein this
latex product 2 can be based on natural latex and on synthetic
latex. The latex products 2 used may or may not be in a
cross-linked state. In the case of a latex product 2 that is not
cross-linked or is only partially cross-linked, the rubber layer
produced has to be additionally vulcanized on the dipping form, by
means of which a carrier layer 3 is constituted.
[0062] Preferably a latex product 2 is used which contains at least
one polymer 5 that is cross-linked or is cross-linked to a large
degree. This latex product 2 is deposited and coagulated on a
dipping form 6, which predetermines the shape of the final product,
and thus produces a thin layer, namely the carrier layer 3
comprised of an elastic, relatively resistant rubber material. The
latex product 2 contains the usual compounding admixtures such as
sulfur, zinc oxide, organic accelerators (among others, zinc salts
of dithiocarbamates, thiurams, thiourea, etc.), stabilizers, waxes,
anti-aging substances, viscosity regulators, fillers, colors, etc..
Natural caoutchouc and synthetic caoutchouc, which is suitable for
use in dipping processes, can be used as the latex product 2 for
the carrier layer 3. Out of the natural and synthetic lattices,
preferably natural caoutchouc, polychloroprene, synthetic
polyisoprene, nitrile-butadiene caoutchouc and styrene-butadiene
caoutchouc, or a mixture of these polymers can be used.
[0063] Naturally, all other manufacturing processes, which are
known to one skilled in the art from the prior art, can be used for
the carrier layer 3.
[0064] It has long been known in the trade that in order to be able
to manufacture reproducible layers out of latex products on a form,
a coagulant is deposited on the form, for example a ceramic form
provided with corresponding roughenings. At the same time, the form
is usually dipped into a basin or a container which contains the
coagulant in fluid form. This coagulant can have any composition
known from the prior art, for example alcohol solutions of calcium
salts or the like. The coagulant also contains a parting compound
such as talcum or calcium carbonate which, if it is acid-soluble,
can be leached from the surface layers with subsequent acid
treatments so that a powder-free glove is produced. The coagulant
is then dried.
[0065] Then, the form with the preferably dried coagulant is dipped
into a container in which the latex product 2 is kept on hand as a
dispersion or fluid so that an average layer thickness of 100 .mu.m
to 300 .mu.m is achieved. Preferably, it is also possible to dip
the form into the latex product 2 several times in order to
increase the layer thickness, where in the mean time, a short
drying of the latex layer can take place.
[0066] Because of the chemical reaction of the latex product 2 with
the coagulant, the latex product 2 deposited in fluid form hardens.
Preferably, immediately after the depositing of the latex product 2
on the form, it is dried for a short time with hot air so that the
surface of the carrier layer 3 hardens or gels, wherein this is
dried for 15 to 60 sec., for example in a heating furnace or a
container through which warm air that is conveyed at a temperature
between 70.degree. C. and 140.degree. C. is conveyed through.
[0067] After this intermediary drying, and in the course of the
above-outlined dipping process, a slip coating 9 made of polymeric
material 10 is deposited on the dried carrier layer 3 at least in a
section 7 of a top side 8 of the carrier layer 3 by means of
dipping or spraying in one or more steps. The layer thickness of
this slip coating 9 can be established in accordance with the
various requirements, in particular the subsequently desired
roughness depth and is between 2 .mu.m and 80 .mu.m, preferably
from 2 .mu.m to 30 .mu.m.
[0068] This slip coating 9 can be comprised of a mixture of a
number of polymeric materials 10 such as an aqueous polyurethane
dispersion. Depending on the intended use, a polyacrylate, a
polysiloxane, a polymethacrylate, a carboxylated styrene-butadiene
copolymer, a polyvinylpyrrolidone, a cationic polyurethane, for
example with a molecular weight of at least 100,000, can be used
just like the nonionic or anionic embodiments of these
above-mentioned materials. These aqueous dispersions and arbitrary
mixtures of them form layers or films with favorable basic
mechanical properties and have elastic properties similar to those
of the carrier layer 3. Naturally, this slip coating 9 can also be
comprised of a mixture of several different polymeric materials 10
in an aqueous dispersion. In this manner, the dispersion is
preferably comprised of a mixture of 0 to 30 wt. % of a
polyurethane dispersion, 1 to 40 wt. % of a polyacrylate
dispersion, 1 to 20 wt. % of a polysiloxane dispersion, and 0 to 10
wt. % fillers, and the remaining portion can be comprised of water.
Powdered or pulverized materials such as chalk, lime, gypsum,
silicon dioxide, and/or cornstarch can be used as fillers. However,
other mixtures can also be used for producing the slip coating 9 in
the article 1 according to the invention or in the glove 4, for
example 5 to 15 wt. % of a polyurethane dispersion, 1 to 8 wt. % of
a polyacrylate dispersion, 2 to 6 wt. % of a polysiloxane
dispersion, and 4 to 6 wt. % fillers, and the remaining portion can
be comprised of water, just as the mixture ratios indicated below
in the individual parentheses, in which ratios the individual
contents in wt. % of the dispersions of polyurethane, polyacrylate,
polysiloxane, and fillers are divided by diagonal slashes, wherein
the remaining portion is brought to 100 wt. % by the addition of
water. The dry content of the dispersions can be determined by one
skilled in the art, wherein the solids content can be between 30
and 50% polyurethane, between 30 and 50% polyacrylate, and between
20 and 40% polysiloxane. These mixtures include the following
weight ratios of polyurethane/polyacrylate/polysiloxane/filler:
(2-7/4-10/3-12/0-5), (0-10/2-6/3-10/3-7), (8-18/5-15/4-7/5-10),
(12-22/12-26/16-20/0-4), (17-26/18-32/10-14/2-6),
(24-30/28-40/15-20/6-9)- , (24-30/25-35/5-10/3-7),
(21-27/4-9/1-4/6-8), (21-27/12-22/3-9/4-7),
(21-27/28-36/12-20/2-7), (9-12/1-3/2-6/5-9), (12-22/4-9/1-4/0-3),
(17-26/5-11/7-10/0-4), (2-7/12-22/14-20/3-8),
(5-15/28-36/14-20/5-10), (0-10/24-29/9-16/5-8).
[0069] In the particular instance of manufacturing dipped articles
as in the case of the article 1, its surface is usually subdivided
into the dipping form side and the dipping bath side. In the
current exemplary embodiment, the dipping form side is called the
underside 11 and rests against the dipping form 6, which can be
comprised for example of porcelain, plastic, or the like.
[0070] The dipping bath side is constituted by either the top side
8 of the carrier layer 3 or the surface 12 of the slip coating 9.
In the current instance, a surface 13 of the dipping form 6 is
preferably provided with regularly repeating shape deviations 14.
These are comprised by shape deviations 14, for example recesses in
the surface 13, or by means of raised areas that protrude above the
surface 13. A ratio of spacings 15, 16 to their depth 17 is between
100:1 and 5:1. As a result, the roughness of the underside 11 of
the article 1 corresponds to the morphology of the dipping form 6.
The depth comes to between 0.5 and 100 .mu.m, preferably between 1
and 40 .mu.m.
[0071] Because of the slight depth 17 of the shape deviations 14,
it should be expressly emphasized at this point that in all
depictions, for the sake of improved schematic representation of
the roughness depth, these shape deviations are shown completely
out of proportion and greatly enlarged in order to be able to
represent and explain the functions and also the disposition of
these shape deviations 14 and the other shape deviations as
well.
[0072] As explained in more detail below, if it is assured that a
layer thickness of the carrier layer 3 as well as of the slip
coating 9 deposited on this is maintained in sections 7 over a
large part of the article 1, then a corresponding roughness is also
embodied on the surface 12 of the slip layer 9 oriented toward the
dipping bath side. This dipping bath side usually forms the inside
of the product when it concerns, for example, sleeve-shaped
articles 1 or thin-walled rubber products since when the articles 1
are pulled from the dipping form 6, the products are turned inside
out. Normally, the surface 12 of the side of the article 1 that
comes into contact with the skin of the user and that should be
correspondingly embodied in order to prevent skin irritations or to
permit the secretion of sweat without irritating the skin. With the
current article 1, it is provided that either the dipping form side
or the dipping bath side or both can be equipped with a
corresponding roughness. Accordingly, it is also possible that a
slip coating 9 can be disposed in sections 7, 18 on one or both
sides, but can of course also be disposed over the entire top side
8 or underside 11.
[0073] Within the scope of the current invention, though, it is
also possible that a slip coating 9 is disposed on both the top
side 8 and the underside 11, wherein this can be carried out by
virtue of the fact that after production of the carrier layer 3,
the article 1 is pulled off the dipping form 6 and put back on the
same dipping form or on a different one inside-out, that is with
the top side 8 resting against the dipping form 6, in order to then
likewise deposit a slip coating 9 onto the underside 11 as well,
which is now disposed on the dipping bath side.
[0074] By means of shape deviations 19, 20 in the slip coating 9,
which are disposed at least in sections 7 on the top side 8 of the
carrier layer 3, perspiration retention can be regulated and
wearing comfort can be increased.
[0075] The contact area between the skin and the slip coating 9 or
the polymeric material 10 should be kept as low as possible in
order to prevent adhesion to human skin, which is wet for example,
by means of which among other things, the danger of skin
irritations and possibly allergic reactions is minimized.
Furthermore, by means of the surface 12 embodied according to the
invention, a favorable slipperiness of the flexible articles 1 in
relation to human skin and as a result, a favorable ability to be
put on when wet or dry is achieved.
[0076] Furthermore, it can clearly be inferred from the depiction
in FIG. 1 that in relation to the shape deviations 14 in the region
of the underside 11 of the carrier layer 3, different shape
deviations 19, 20 are simultaneously disposed in the surface 12 of
the slip coating 9. These shape deviations 19, 20 are disposed
between intermediary pieces 21, 22 of a net-like structure 23 or
are to a large extent encompassed by them. In relation to the
surface 12 of the intermediary pieces 21, 22, the shape deviations
19, 20 have different depths 24, 25, wherein these depths 24, 25
also change over the area of the shape deviations 19, 20 and can
possibly reach down to the carrier layer 3, as shown for example in
the shape deviation 19. The depth 24 of this shape deviation 19
thus corresponds to the overall thickness of the slip coating 9,
which can be between 2 and 80 .mu.m, preferably between 2 and 30
.mu.m.
[0077] In addition, spacings 15, 16 between the individual shape
deviations 19, 20 vary widely. Consequently, the ratio of the
average spacings 15, 16 between the individual shape deviations 19,
20 to their depths 24, 25 in relation to the raised, net-like
structure 23 or the intermediary pieces 21, 22 lies between 500:1
and 5:1. The average roughness depth, for example, lies between 0.5
and 100 .mu.m, preferably between 1 and 40 .mu.m.
[0078] As is furthermore schematically visible in the depiction in
FIG. 1, 50 to 90%, preferably 60 to 80% of the partial area or of
the section 7 is disposed as recessed by means of shape deviations
19, 20. Preferably, at least 50% of the shape deviations 19, 20 in
the top view of the slip coating 9 are encompassed on all sides by
the net-like structure 23, in particular by the intermediary pieces
21, 22.
[0079] Furthermore, in a preferable manner, an average roughness
depth of the slip coating 9 or of the partial area of the section 7
lies between 0.5 and 100 .mu.m, preferably between 1 and 40 .mu.m.
This average roughness depth represents the mathematical average of
individual roughness depths, which are determined in five adjoining
individual measured sections of equal length, as is explained in
more detail below in conjunction with the exemplary embodiment in
FIG. 2. What is achieved as a result is that a quite uniform
adhesion potential or slip potential is achieved between the
individual regions of the surface 12 or, in the event that the
underside 11 is coated with a slip coating 9, on the surface
connected with it, by means of which the slipperiness of the
article 1 and primarily also the wet slipperiness can be
considerably improved.
[0080] This differs from the processes of the prior art in that the
product properties according to the invention are predominantly
achieved via the roughness of the surface 12 or the underside 11,
wherein with increasing average roughness depth of up to approx. 40
.mu.m, the slipperiness in relation to human skin increases and the
stickiness of the polymer surfaces decreases.
[0081] If the surface 12 or the underside 11, which constitutes the
outer surface of the glove 4 is further roughened, in most
products, a subjectively uncomfortable abrasive feel gradually
increases as a function of hardness and modulus of elasticity. With
roughness depths of over 100 .mu.m, a significant increase in the
polymer-polymer friction usually occurs and when there is abrasive
contact with human skin, possibly leads to mechanically caused
irritations. The surface properties described here with regard to
their dependency on the average roughness depth are naturally also
dependent on the type of roughness and the type of manufacturing
used to produce it, as well as the polymer type and product type
and have to be individually optimized for each polymer type and
product type. It is advantageous that individual irritation zones
in the sections 7, 18 that can negatively influence the positive
overall effect of the embodiment according to the invention are
fundamentally prevented by the average roughness depth, which is
uniform over the sections 7 and 8, respectively.
[0082] In contrast to the surface roughnesses according to the
invention, favorable slipperiness in relation to human skin can
furthermore also be achieved with relatively soft polymers (e.g.
polyacrylates), whereas with conventionally smooth slip coatings
having the same polymers, there is no slipperiness in relation to
skin. Because of the fact that softer polymers having higher
tensile elasticities can be used in the surface layers according to
the invention, with thin-walled articles 1 having high elasticity,
the adhesion problems of the surface layer are reduced when the
layer is stretched. Furthermore, the selection of the slip coating
polymer is made significantly easier since the main influence
factor for wearing comfort and slipperiness according to the
invention is determined by the surface morphology.
[0083] The embodiment of an article l in the form of a powder-free
glove 4, e.g. a medical glove, is represented in the variant in
FIGS. 2 and 3.
[0084] The glove 4 depicted in FIGS. 2 and 3 is shown in the
position it assumes when removed from the dipping form 6, wherein
the surface 12, which is oriented toward the dipping bath side
during production and receives the slip coating 9, constitutes the
inside of the glove 4, while the underside 11 oriented toward the
dipping form 6 during the production of the glove 4 constitutes the
outside of the glove 4. Consequently, in the case of this glove 4,
on the outer surface which the user of the glove 4 uses to grasp
tools or components, there is a corresponding average roughness
depth that lies between 0.5 and 100 .mu.m, preferably between 1 and
40 .mu.m, and is an image of the average roughness depth of the
surface of the dipping form 6.
[0085] In order to produce the uniform morphology, as has also
already been briefly explained by way of introduction, the dipping
form 6 is used, which is usually slightly rough and is comprised of
porcelain, and which has an average roughness depth between 0.5 and
100 .mu.m, preferably 1 to 40 .mu.m; it is dipped into an aqueous
coagulation solution, which is comprised of e.g. calcium nitrate,
polyethylene glycol, and a water soluble silicone type or chalk and
is then dried for a short time with hot air. Then, for the
depositing of the glove 4, the dipping form 6 is dipped into a for
example pre-cross-linked natural latex mixture of which the carrier
layer 3 is comprised.
[0086] The average roughness depth represents the mathematical
average of individual roughness depths 26 to 30, which are
determined in five adjoining individual measured sections of equal
length 31. The average roughness depth in the region of the surface
13 thus represents a mirror image of the average roughness depth of
the dipping form 6.
[0087] The average roughness depth on the surface 12 of the slip
coating 9--which is deposited on the carrier layer 3 by means of
the immersion of the dipping form 6 after a renewed short
drying--is determined in the same manner by means of the individual
roughness depths 26 to 30 in five adjoining individual measured
sections of equal length 31.
[0088] However, the shape deviations 19 and 20 in this surface 12
are now either not influenced at all by the surface morphology of
the dipping form 6 or are influenced by it to a reduced extent in
accordance with the selected process, and are instead constituted
by means of the manufacturing process during the production of the
slip coating 9.
[0089] In the end view of the glove 4 in FIG. 3, it can be seen
that the entire surface 12 that comprises the inside of the glove 4
is provided with corresponding shape deviations 19, 20 in
accordance with the above description.
[0090] Moreover, for example, the underside 11 that comprises the
outside of the glove 4 is provided with corresponding shape
deviations 14, i.e. a roughening, only in the region that comes to
rest over the inner surface of the hand, in order for example to
improve grip security primarily when the gloves are used to grasp
tools in the medical field or also in the assembly field.
Naturally, it is also conversely possible to equip the entire
underside 11, that is, the entire external surface of the glove 4,
with corresponding shape deviations 14 and with a roughness
comprised by means of this. The degree to which the section or a
partial area of the section 18 is provided with shape deviations 14
or a roughening can be determined by the embodiment of the dipping
form 6, in particular its surface roughness.
[0091] For the sake of increased clarity, this manufacturing
process, which produces the average roughness depth shown
schematically and completely out of proportion in the drawings in
FIGS. 2 and 3, is explained in detail in conjunction with the
schematically represented course of the process for manufacturing
this kind of an article 1 or glove 4 by means of individual,
successive apparatuses and apparatus parts represented in FIGS. 4
and 5.
[0092] To manufacture preferably powder-free gloves 4 out of a
latex product 2, a number of dipping forms 6 are disposed on a form
carrier 32 and are comprised, for example, of porcelain, plastic,
metal, aluminum, or the like, with a surface 13 that has the
desired shape deviations 14 in accordance with the above-indicated
average roughness depth, while dipping forms 33 are disposed on the
form carrier that have a smooth surface for the subsequent outside
of a glove 4 to be manufactured out of latex.
[0093] The form carrier 32 is oriented toward a dipping basin in
which an aqueous coagulation solution 35 is disposed. As has
already been indicated by way of introduction, this can be
comprised of calcium nitrate, polyethylene glycol, and a water
soluble silicone type or chalk. As indicated by the arrow 36, the
form carrier 32 is dipped into the dipping basin 34, then removed
from it in accordance with the arrow 37 and if need be, after an
intermediary drying--as symbolically indicated by a hot air blower
38 and the arrows 39 that schematically represent the air heated
for drying--are conveyed to another dipping basin 41 in accordance
with the dotted lines 40.
[0094] Naturally, within the scope of this process according to the
invention, it is left up to one skilled in the art as to whether
the dipping of the dipping forms 6 or the form carrier 32 always
takes place in the same dipping basin 34 and this basin is
alternatingly filled with coagulation solution 35 or the latex
product 45 or arbitrary other fluids or mediums via an inlet 42 and
a discharge 43, e.g. via a schematically represented pump 44, or
whether a number of dipping basins 34, 41, 46, 47, 48, 49, 50 are
provided which are disposed in succession. It is also possible that
the dipping of the dipping forms 6 is carried out by a relative
movement of an arbitrary type between the form carrier 32 and the
dipping basin 24, 41, and 46 to 50. Naturally, it is also possible
that primarily the treatment steps or process steps in which the
articles 1 or gloves 4 are already removed from the dipping forms
6, 33, are carried out in rotating containers, for example drums or
the like, such as the ones used in conventional washing machines
and driers, in order to move them during the treatment by means of
constant rotation of the drum in order to also prevent the articles
1 or gloves 4 from sticking to each other during production.
[0095] Since all of these different possibilities for carrying out
the process are known to one skilled in the art from the broad
prior art, the depiction of the different devices for carrying out
the individual steps of the process are eliminated and these are
only explained in conjunction with the purely schematic
representations in FIGS. 4 and 5.
[0096] After this intermediate drying of the coagulant or the
coagulation solution 35 that is carried out if necessary, the
dipping forms 6 are dipped into the dipping basin 41 so that the
dipping forms 6 and 33 are dipped completely below a fluid level 51
of a latex product 45 of arbitrary composition, as previously
indicated. The dipping forms 6 remain in the dipping basin 41 until
a desired layer thickness of fluid latex product 45 can adhere to
the surface of the dipping forms 6 or to the layer comprised of
coagulation solution 35. To that end, it is also possible that the
dipping forms 6, 33 are lifted out of the dipping basin 41 and
dipped back into it several times.
[0097] Then, a short intermediary drying of the latex product 45 on
the dipping forms 6, 33 is carried out in accordance with the
dotted line 40, for example with hot air at the additional hot air
blower 38, for which purpose the air can have a temperature from 70
to 140.degree. C., preferably 90 to 110.degree. C. and the dipping
forms 6 can be exposed to this hot air for 15 to 60 sec..
Preferably, the duration of hot air exposure and the temperature of
the hot air are controlled so that on its surface, the layer of
fluid latex product 45 passes from the liquid state into the
gelatinous or solid state.
[0098] After that, the form carrier 32 with the dipping forms 6,
33, in accordance with the arrows 36, 37, is dipped into the
dipping basin 46 in which a polymeric material 10 for producing the
slip coating 9 is disposed. At this point, for the sake of clarity,
it should be mentioned that it is naturally possible to adapt the
viscosity of the polymeric material 10 or naturally also the
viscosity of the latex product 45 or the coagulation solution 35 to
the desired properties through the addition of one or more
viscosity regulators which, to one skilled in the art, are known
from the prior art in different embodiments. As a result, it is
possible to adapt the viscosity of the products or materials, which
are usually in the form of dispersions, to the desired employment
purpose in order to achieve corresponding layer thicknesses when
dipping or to achieve a uniform depositing of the various materials
on a surface of the dipping forms 6, 33. For the sake of clarity,
it should be mentioned at this point that in the current
description, the term "latex" has been constantly used
independently of whether it concerns a dispersion of this material,
the hardened, dried, cross-linked layer, or the solid phase of this
material, even it for example in the case of natural latex, this
substance is usually called caoutchouc. It would therefore also be
possible to refer to the layers, which are comprised of the
individual materials mentioned above, as caoutchouc layers. This
polymeric material 10 can be composed in accordance with the
preceding data.
[0099] After the form carrier 32 with the dipping forms 6, 33 is
lifted out of the dispersion comprised of polymeric material to
produce the slip coating 9, this additionally deposited slip
coating 9, as schematically indicated, is dried with hot air, for
example at a temperature between 70 and 140.degree. C., preferably
90 to 110.degree. C., for a period of 15 to 60 sec.. Preferably,
the temperature and the duration of the hot air treatment are
modulated so that the surface of the slip coating 9 passes over
into a gelatinous or solid state.
[0100] Immediately after this, the dipping forms 6, 33 with the raw
parts of the articles 1 or gloves 4 disposed on them are dipped
into another dipping basin 47 in which the slip coating 9 is
sprayed or rinsed with hot water 52. To that end, the hot water 52
can be circulated through the dipping basin 47 by means of a pump
44 belonging to a heating furnace or a heat exchanger 53, by means
of which the air is kept at a desired temperature between 40 and
95.degree. C., preferably from 70 to 90.degree. C.
[0101] The chemical reaction in the slip coating 9 and the carrier
layer 3 is initiated or supported by means of this treatment with
hot water 52 so that it leads to a beginning or to a complete
coagulation in this layer.
[0102] After this hot water treatment, which can last from 15 sec.
to 8 min., preferably 30 sec. to 4 min., the articles 1 or the
gloves 4, in the position in which they are put on the dipping
forms 6, 33, are removed from the dipping basin 47 so that the
remaining water 52 can drain off.
[0103] FIG. 5 shows the continuation of the course of the process
in accordance with the line V-V in FIG. 4. The gloves 4 removed
from the water 52 are left in the open for a period of 10 to 180
sec., preferably 20 to 50 sec., which time serves as a draining
period, or are dried by hot air, before they are acted upon by
means of an infrared radiation in the dipping basin, in this
instance a warming cabinet or heating furnace, so that the carrier
layer 3 and the slip coating 9 are permanently fixed. The radiation
surfaces 54 for the infrared radiation, which are preferably
embodied as stove tiles, have a temperature between 350 and
700.degree. C., and the articles 1 or gloves 4 are exposed to
infrared radiation indicated schematically by the arrows 55 for a
period of time between 1 and 5 min. To this end, it is necessary
that by means of the dipping basin 48 or a corresponding drying
device, the ambient air, in accordance with the schematically
indicated arrows 57, can be blown through the heating chamber or
the dryer or the dipping basin 48 by means of a ventilator 56.
[0104] After the drying of the articles 1 or the gloves 4, the
dipping forms 6, 33, as shown in FIG. 5, are dipped with their form
carriers 32 into the dipping basin 49, in which a parting compound
58, for example a powder such as talcum, chalk or cornstarch
powder, or a silicon emulsion is disposed which, when the articles
1 or the gloves 4 are subsequently removed from the dipping forms
6, 33, and are simultaneously turned inside-out, should prevent the
surfaces 12 oriented toward the dipping basins 34, 41, and 46 to 48
from sticking together.
[0105] After being removed, the articles 1 or the raw pieces of the
gloves 4 are placed, for example, in a transport basket 59, which
can also be shaped like a grating or can be provided with through
openings, and this transport basket 59 is placed in the dipping
basin 50 in which a bleach 60 is disposed, whose composition is
known from the prior art. For example, a 0.5% sodium hypochloride
mixed with approx. 0.2% hydrochloric acid can be used.
[0106] After the treatment with the bleach 60, the articles 1 or
the gloves 4 are washed at least once, preferably several times,
though, with water or with fluids known from the prior art, in
order to remove the residues of bleaches or acids from e.g.
separate treatments with acids and bleaches.
[0107] When this washing process is finished, the articles 1 or the
gloves are placed with the transport basket 59 into a dipping basin
48 or into a drying chamber, in which heating elements 61 can be
disposed either in the drying chamber or in an air intake duct for
the air drying, so that the drying is carried out by means of air,
schematically represented by arrows 62, which can be conveyed
through the interior of the drying chamber via the ventilator 56 or
a blower.
[0108] Naturally, any other form of drying is also possible, for
example by using drums or the like. When a drying chamber of this
kind is used, it is preferably possible to blow a silicone emulsion
into the air flow via an additional line 63 in accordance with the
arrow 64 shown, in order, for example, to coat the surfaces that
constitute the outside of the glove 4 and if need be, those that
constitute its inside, with silicone near or at the end of the
drying process. Naturally, however, it is also possible to deposit
this silicone coating in particular sections of the slip zones or
the surface 12 or 13 in a likewise known manner by means of the
dipping process in emulsions or by means of spray application.
[0109] With the above-described process, the roughness according to
the invention or the average roughness depth in the slip coating 9
is achieved by virtue of the fact that while the slip coating 9 is
being acted upon by the hot water 52, or immediately thereafter, 40
to 70%, preferably 50 to 60% of the water content is removed from
the slip coating 9. Due to the rapid removal of water, relatively
high surface tensions are produced in the region of the slip
coating 9 and this leads to a lowering or reduction of the
thickness of the slip coating 9 shown in FIG. 1, which can be
between 2 and 80 .mu.m, preferably from 2 to 30 .mu.m, and
corresponds, for example, to the depth 24 in FIG. 1, at which the
shape deviation 19 is so large that it extends over the entire
thickness of the slip coating 9, i.e. down to the top side 8 of the
carrier layer 3.
[0110] These regions with reduced wall thickness of the slip
coating 9 comprise the shape deviations 19, 20, which are to a
large extent encompassed by the net-like structure 23 or its
intermediary pieces 21, 22. These raised intermediary pieces 21, 22
of the net-like structure 23 cause the article 1 or the glove 4 to
lie against the surface of human skin only along the intermediary
pieces, and on the one hand, the area of contact with the skin is
significantly reduced and on the other hand, the slipperiness, in
particular the wet slipperiness, is considerably increased as a
result. At the same time, cavities are produced in this way, which
can also absorb the sweat produced during work so that the wearing
comfort of this kind of articles 1 or gloves 4 is also considerably
improved.
[0111] This improved slip effect can be increased even further by
additionally depositing a layer of silicone, for example by means
of immersion into a silicone emulsion or by means of charging the
drying air with a silicon emulsion.
[0112] If the articles 1 or gloves 4 are supplied in loose form to
a bleaching process for bleaching the side remote from the dipping
bath when the slip coating 9 is being deposited, which side then
comprises the outside of the article 1 or glove 4, then as a
result, the slipperiness of the article 1 or the glove 4 can be
still further improved.
[0113] After the drying process has been carried out in the dipping
basin 50, the gloves 4 are then sorted together into pairs and
supplied to other processing procedures such as sterilization and
packaging.
[0114] The roughness according to the invention, though, can also
be increased by means of many other known processes.
[0115] The simplest method for roughening articles 1 in addition to
the roughness depth required by manufacture is comprised in that
the dipping form 6, 33 which is covered with the still-soft article
1 or the slip coating 9, is conveyed, for example, through a
sandblasting chamber or through a fluidized bed with fine glass
beads. Excess particles from the blasting process usually have to
be completely removed in subsequent steps of the process.
[0116] Finally, in conjunction with a section through a glove 4
disposed on a dipping form 33, FIG. 6 shows that through the use of
the dipping process, first a coagulation solution 35 is deposited
on the surface that is for example embodied as smooth, followed by
a latex product 45, whereupon the slip coating 9 is applied by
dipping or spraying.
[0117] Through a corresponding embodiment of the devices for
pressing the average roughness depth or the shape deviation 19, 20
into the surface 12, for example the above-mentioned glass beads or
a corresponding pressing die can be used to produce additional
roughening in the partial areas 65 to 68, before the manufacture of
the above-described roughenings because of the shape deviations 19,
20.
[0118] For example, these partial areas extend only over a part of
the horizontal faces of the article 1 that rest against the hand of
the user. As a result, a sufficient wet slipperiness is achieved
without the entire article being too severely weakened since in
many cases, a high degree of slipperiness only has to be produced
on those surfaces acted upon by an initial tension for the purpose
of firmly seating the article 1 on a body part of the user. Within
the scope of the invention, it is naturally also possible that by
means of corresponding arrangements, for example the partial
depositing of parting compounds or the like before the slip coating
9 is deposited, the slip coating 9 or at least the shape deviations
19, 20 are also produced on only one partial area or on individual
partial areas 65 to 68.
[0119] Furthermore, the depiction in FIG. 6 shows that the carrier
layer 3, which is comprised of the coagulation solution 35 and the
latex product 45, can have a thickness 69 of 100 .mu.m to 300
.mu.m.
[0120] In contrast, the slip coating 9 disposed on this carrier
layer 3 has, for example, a thickness 70 of 2 .mu.m to 80 .mu.m,
preferably 2 .mu.m to 30 .mu.m.
[0121] FIG. 7 shows a top view of a part of the surface 12 of the
slip coating 9 of an article 1. This depiction very clearly shows
the net-like structure 23, which is comprised by means of the
intermediate pieces 21, 22 and encompasses the shape deviations 19,
20.
[0122] This depiction is a 100-fold enlargement of the surface 12
of the slip coating 9, produced by an electron microscope.
[0123] The variants described in the preceding figures as to choice
of material for the carrier layer 3 and the slip coatings 9 can be
used interchangeably. Naturally, the individual exemplary
embodiments described above, the variants shown in these exemplary
embodiments, and different embodiments can each constitute
independent inventive embodiments in and of themselves and can be
arbitrarily combined with one another. Primarily, the individual
embodiments characterized in FIGS. 1-7 can constitute the subject
of independent embodiments according to the invention. The objects
and embodiments according to the invention with regard to this can
be inferred from the detailed descriptions of these figures.
[0124] For the sake of clarity, is should be emphasized that for
improved comprehension of the invention, the individual exemplary
embodiments have been represented in a form that is partially
distorted in scale or have been shown in enlarged fashion.
Individual features of the combinations of features shown in the
individual exemplary embodiments, all constitute embodiments
according to the invention that are independent in and of
themselves.
1 Reference Numeral List 1 article 36 arrow 2 latex product 37
arrow 3 carrier layer 38 hot air blower 4 glove 39 arrow 5 polymer
40 line 6 dipping form 41 dipping basin 7 section 42 inlet 8 top
side 43 discharge 9 slip coating 44 pump 10 material 45 latex
product 11 underside 46 dipping basin 12 surface 47 dipping basin
13 surface 48 dipping basin 14 shape deviation 49 dipping basin 15
space 50 dipping basin 16 space 51 fluid level 17 depth 52 water 18
section 53 heat exchanger 19 shape deviation 54 radiation surface
20 shape deviation 55 arrow 21 intermediary piece 56 ventilator 22
intermediary piece 57 arrow 23 structure 58 parting compound 24
depth 59 transport basket 25 depth 60 bleach 26 individual
roughness depth 61 heating element 27 ind. roughness depth 62 arrow
28 ind. roughness depth 63 line 29 ind. roughness depth 64 arrow 30
ind. roughness depth 65 partial area 31 length 66 partial area 32
form carrier 67 partial area 33 dipping form 68 partial area 34
dipping basin 69 thickness 35 coagulation solution 70 thickness
* * * * *