Note: Descriptions are shown in the official language in which they were submitted.
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WATER-RESISTANT AND CHEMICAL-RESISTANT GLOVE
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority and the benefit of the filing
date
of U.S. Provisional Patent Application Serial No. 61/363,871, filed on July
13, 2010,
which is herein incorporated by reference.
FIELD
[0002] The present application pertains to water-resistant and chemical-
resistant gloves. More particularly, the present application relates to
flexible,
sensitive, water-resistant and chemical-resistant gloves made by the use of a
dip-
line process.
BACKGROUND
[0003] Although there are many types of chemical-resistant gloves available,
most suffer the disadvantage of being uncomfortable to the wearer due to the
presence of stiff, inflexible materials.
[0004] Historically, in order to obtain the necessary chemical and water
resistance, various membranes impervious to certain chemical agents and water
were laminated or heat-sealed together to produce a glove. These gloves were
typically insensitive and stiff, which made hand movement difficult for the
wearer.
[0005] Therefore, there exists a need for a water-resistant and chemical-
resistant glove that is flexible and comfortable and that is made by a dip
line
process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Fig. 1 illustrates a glove that can be formed according to the present
application; and
[0007] Fig. 2 is a depiction of an exemplary cross-section of a portion of the
glove of Figure 1.
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DETAILED DESCRIPTION
[0008] While embodiments of this application can take many different forms,
specific embodiments thereof are shown in the drawings and will be described
herein in detail with the understanding that the present disclosure is to be
considered as an exemplification of the principles of the application, as well
as the
best mode of practicing same, and is.not intended to limit the application to
the
specific embodiment illustrated.
[0009] The present application relates to a skin-covering, which has improved
comfort and also improved resistance to water and chemical permeation. The
present application includes a method of forming such a skin-covering. The
skin-
covering can be a five-fingered glove, but it also can be a mitten having only
a
thumb or a mitten having any combination of fingers present from zero to five.
(See
Figure 1) Such skin-covering is not limited to a glove or mitten, and can
comprise
an apron, coat, hat, scarf, sock or shoe.
[0010] The chemical-resistant nature of the glove results from the presence of
a multi-layer composition of at least two substantially water-proof layers and
a
chemical-resistant layer. The substantially water-proof layer is comprised of
a
mixture of polyurethane and nitrile, although generally it can be made of any
material that imparts a substantially water-proof character to the glove, such
as
polyethylene, nitrile, polyurethane, chloroprene latex, natural latex, butyl
latex,
fluoric latex, and mixtures thereof. The chemical-resistant layer is comprised
of
polyvinyl alcohol (PVA), although any material that imparts a chemical-
resistant
nature to the glove is useful.
[0011] Optionally, the glove also comprises a donnable layer, which lies next
to the skin. In terms of orientation, the PVA layer is sandwiched between two
substantially water-proof layers, preferably comprised of a mixture of
polyurethane
and nitrile. The layer of the polyurethane and nitrile mixture also provides
chemical
resistance.
[0012] The PVA layer provides chemical permeation resistance. It is well-
known that a broad range of chemicals such as organic solvents, plasticizers,
pesticides and detergents cannot readily permeate PVA. U.S. Patent Numbers
4,902,558 and 5,059,477, and U.S. Application Serial Numbers 12/862,311;
61/363,871; and 61/393,712, each assigned to Honeywell, which are hereby
incorporated by reference, discuss the advantages of having a PVA layer in a
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chemical-resistant glove. These patents explain that water will tend to swell
and
plasticize the PVA layer. Therefore, the PVA layer should be protected on both
top
and bottom from the presence of water. Accordingly, if the PVA layer is next
to a
donnable layer, the donnable layer must be substantially water-proof. Suitable
donnable layers include those of synthetic fiber, natural fiber, chloroprene
latex,
natural latex, butyl latex, fluoric latex, polyurethane, polyethylene and
mixtures
thereof. The donnable layer can be cotton, polyurethane or latex rubber. A
substantially water-proof fabric material is also contemplated.
[0013] It is to be understood that there is no set limitation as to the number
of
layers that the glove can have so long as the glove is comfortable and
flexible
enough for its intended use. There is also no limitation as to the presence of
duplicate layers.
[0014] One embodiment of the glove (10) comprises multiple layers, including
at least one outer layer of a mixture of polyurethane and nitrite (12),
enclosing and
protecting one adjacent layer of PVA (14), which is directly adjacent to
one/two
polyurethane and nitrile mixture layers (16-18) for a grand total of three to
five
layers. (See Figure 2)
[0015] Layer 20 is the donnable layer, which when worn is adjacent to the
skin of the wearer and is optional. There are no restrictions as to the
arrangement
of the layers except that the PVA layer preferably is protected from moisture.
Also,
the thickness of the layers ranges from about 0.1 mm to about 1 mm for both
the
polyurethane and nitrile mixture layer and the PVA layer. The glove can
contain
about 1 to 70 weight percent polyvinyl alcohol and 1 to 70 weight percent
polyurethane and nitrile mixture. The thickness of the donnable layer is in
the range
of about 0 mm to about 6 mm thick, or about 0 to 50 weight percent.
[0016] In another embodiment, the polyvinyl alcohol layer (14) is in the range
of about 1 to 70 weight percent and the polyurethane and nitrile mixture layer
(12) is
in the range of about 1 to 70 weight percent, and the polyurethane and nitrile
mixture layer (16-18) is in the range of about 1 to 70 weight percent.
[0017] The present application also contemplates a method of forming a
water-resistant and chemical-resistant glove. The method can also encompass
the
addition of one or more additives wherein the additives comprise an adhesive,
a
colorant, an anti-microbial agent, a fiber, a fragrance or mixtures thereof.
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[0018] The method of forming a water-resistant and chemical-resistant glove
comprises optionally placing a donnable layer (i.e., liner) on a hand-shaped
former,
optionally placing a coagulant on the hand-shaped former, then dipping the
hand-
shaped former into a polyurethane and nitrile mixture so that a continuous
layer of
the mixture is deposited on the former and removing the former from the
mixture;
dipping the former into an aqueous solution of polyvinyl alcohol so that a
continuous
layer of polyvinyl alcohol is deposited on the former and removing the former
from
the polyvinyl alcohol solution; dipping the former into a polyurethane and
nitrile
mixture so that a continuous layer of the mixture is deposited on the former
and
removing the former from the mixture. The glove can then be stripped from the
former. The paired dipping and removing steps can be independently repeated
multiple times to form multiple layers, as desired. A donnable layer (i.e.,
liner) can
optionally be placed on the glove as the final step in addition to or instead
of the first
step.
[0019] Example 1: A chemical and mechanical resistant glove was made the
process below. A porcelain former was cleaned and dried. The former was then
dipped into a calcium nitrate coagulant solution. It remained in this solution
for
about 15 seconds. The former was then withdrawn from the solution and allowed
to
dry at room temperature. Next, the coated former was dipped into a mixture of
polyurethane and nitrite, also having color pigments dispersed therein. The
dwelling
period was about 30 seconds. The former was then withdrawn and dried for about
14 minutes. Next the former was dipped into a polyvinyl alcohol solution. The
dwell
period was about one minute. The former was then removed from this solution,
allowed to dry for about 17 minutes at about 65 C, then cooled at room
temperature
for about 8 minutes. Next, the coated former was dipped twice into a
polyurethane
and nitrite mixture. The dwell time was 0 seconds. Each dipping had a drying
time
of 4 minutes at 65 C. Next, cotton flock was put on. The glove was dried and
stripped from the former.
[0020] From the foregoing, it will be observed that numerous variations and
modifications may be effected without departing from the spirit and scope of
the
application. It is to be understood that no limitation with respect to the
specific
article and/or method illustrated herein is intended or should be inferred. It
is, of
course, intended to cover by the appended claims all such modifications as
fall
within the scope of the claims.
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