EP2818064B1

EP2818064B1 - Chemically-resistant gloves with anti-static properties

Info

Publication number: EP2818064B1
Application number: EP13173904.7A
Authority: EP
Inventors: Jens Neumann
Original assignee: Honeywell International Inc
Current assignee: Honeywell International Inc
Priority date: 2013-06-26
Filing date: 2013-06-26
Publication date: 2015-07-15
Anticipated expiration: 2033-06-26
Also published as: EP2818064A1

Description

TECHNICAL FIELD

Various embodiments relate generally to gloves, and in particular to anti-static and chemically resistant gloves.

BACKGROUND

In many occupations, gloves are important to protect a person from dangerous chemicals. Chemically-resistant gloves are used in the pharmaceutical industry for example. Chemically-resistant gloves are also used in many other industries, such as micro-electronics and industrial chemicals. Strong solvents are even used in regular homes and other businesses. When using such chemicals, a person typically wears a chemically resistant glove to skin exposure to the chemical. See for example US 2011/099 689 .
In many occupations potentially explosive vapors may exist. For example, in the petroleum industry many workers work in environments in which very flammable liquids and gases are used. In some industries such as corn and grain storage, flammable dust abounds. Even when one puts gas into one's car, flammable vapors are present. In these and many other scenarios, a spark could lead to a terrible catastrophe. In such situations, care is needed to prevent electrostatic discharges from occurring.

SUMMARY

Apparatus and associated methods may relate to an Anti-Static Chemically-Resistant Glove (ASCRG). In accordance with an exemplary embodiment, an ASCRG may have an outer shell which includes a butyl-rubber compound having a carbon-black filler, which may enhance the outer shell's electrical conductivity. In various embodiments, the ASCRG may have an inner liner having metallic fibers in direct contact with a wearer's skin. In some embodiments these metallic fibers may contain stainless steel. In some embodiments these metallic fibers may contain silver. In various embodiments the inner liner may be glued to the inside of the outer shell. For example a water-base acrylic glue may be used in various embodiments to attach the liner to the inside of the outer shell. In some embodiments the vertical resistance as measured by the EN 1149-2:1997 standard may be less than about 1x10⁸ Ohms at 23 degrees Celsius and 25 percent relative humidity.
Various embodiments may achieve one or more advantages. One key advantage, for example, may be to provide simultaneous chemical protection of a wearer while substantially mitigating the risk of explosion in chemical exposure environments. For example, some embodiments may use cotton yarn with stainless steel fibers which may promote comfortable wear. In various embodiments, the outer shell of an ASCRG may be textured to improve the friction of the exterior surface. In some embodiments, a vertical resistance, which is the electrical resistance between the outside of the outer shell to the inside of the inner liner, of less than 1x10⁸ Ohms at 23 degrees and 25 percent relative humidity, may prove beneficial. In some embodiments even lower vertical resistances may prove useful, such as for example less than 1x10⁶ Ohms.
The details of various embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an exemplary field application of an exemplary Anti-Static Chemically-Resistant Glove (ASCRG).
FIG. 2 depicts a perspective view of two exemplary ASCRGs.
FIGs. 3A-3B depict an exemplary inner liner of an ASCRG, along with a close-up figure of an exemplary knitting of the depicted liner.
FIGs. 4A-4C depict three exemplary electrically-conductive yarns used in exemplary ASCRGs.
FIG. 5 depicts a close-up of a cross-section of and exemplary ASCRG showing inner liner, adhesive, and outer shell.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 depicts an exemplary field application of an exemplary Anti-Static Chemically-Resistant Glove (ASCRG). This figure depicts the gas station refueling scenario 100. In this figure, a fuel truck 105 is parked next to a ground-level fuel-tank door 110 which provides access to an underground fuel tank 115. A driver 120 has placed a fuel hose 125 into the underground fuel tank door 115. The fuel hose 125 is connected to the fuel truck 105. The driver 120 is wearing ASCRGs 130 so as to protect the user from skin contact with the fuel and simultaneously to prevent the user from inducing a static discharge event which could prove disastrous in this fuel-rich scenario. The ASCRGs 130 have a flexible outer shell 135 that is chemically-resistant, so as to protect the driver's hands from exposure to the fuel. The ASCRGs 130 also have a comfortable inner liner 140 that is electrically conductive to substantially resist charge build-up. The inner liner 140 is glued to the inside of the flexible outer shell 135. In various examples, the vertical resistance measured from the outside of the flexible outer shell 135 to the inside of the inner liner 140 may be less than 1x10⁸ Ohms at 23 degrees Celsius and 25 percent relative humidity.
FIG. 2 depicts a perspective view of two exemplary ASCRGs. In the FIG. 2 embodiment, two ASCRGs 200, 205 are depicted. The first ASCRG 200 is depicted in a right-side-out fashion revealing its flexible outer shell 210. In this embodiment, the outer shell has a hand region 215 and a wrist region 220. In this embodiment, the flexible outer shell may be manufactured by dipping a porcelain hand former into a butyl-rubber mixture containing a carbon-black filler. The carbon-black filler may give the gloves a measure of electrical conductivity. The hand formers may be dipped into one or more baths of butyl-rubber mixtures one or more times, until the desired glove thickness is achieved. In some embodiments, a final dipping of the hand region only may finish the dipping process. In some exemplary embodiments, this final dipping or dippings of the hand region only may be performed to give the glove additional thickness in the hand region. In some embodiments, this final dipping or dippings may be performed by using a different composition of the butyl-rubber glove compound. This final dipping or dippings may be performed in a butyl-rubber bath containing a texturing substance, for example. Using such a texturing compound may provide the hand region of the glove's exterior a different frictional property, for example. In some embodiments, the hand region may be rough, for example, in comparison with the wrist region, which may be smooth, for example.
The second ASCRG 205 is depicted with a wrist region 225 turned inside-out so as to expose an inner liner 230. In some embodiments the inner liner may include metallic fibers. The metallic fibers may give the inner liner a measure of electrical conductivity. In some embodiments the metallic fibers may include stainless-steel fibers. In some embodiments the metallic fibers may include silver fibers. In some embodiments the metallic fibers may include silver-impregnated polymer fibers. In some embodiments the metallic fibers may account for a small fraction of the inner liner's material. In some embodiments the metallic fibers may account for substantially all of the inner liner's material. In various embodiments, these metallic fibers may directly contact a wearer's skin.
FIGs. 3A-3B depicts an exemplary inner liner of an ASCRG, along with a close-up figure of an exemplary knitting of the depicted inner liner. In the FIG. 3A embodiment an inner liner 300 is depicted in isolation. The inner liner may be affixed to the inside of an outer shell 235 by an adhesive, for example. In some embodiments the outside shell 235 may be turned inside-out and put on a hand former, for example. Then the hand former may be dipped into a water-based acrylic adhesive, for example. The liner may then be put onto the inside-out outer shell 235. The adhesive may then be cured in an oven, for example, before the glove is turned right-side-out. In FIG. 3A, an inside-out glove with an inner liner 305 is depicted. FIG. 3B shows a close-up drawing of the fabric 310 of the inner liner 305. In some embodiments, the inner liner 305 may comprise fabric 310 which may provide relative comfort to a wearer. In various embodiments the fabric 310 of the inner liner 305 may contain electrically conductive fibers which may make direct electrical contact with a wearer's skin. In some embodiments, the metal fibers may electrically contact the inside of the outer shell 235 when the liner 305 is glued to the outer shell 235.
FIGs. 4A-4C depict three exemplary electrically-conductive yarns used in exemplary ASCRGs. In FIG. 4A, an exemplary metallic yarn 400 is depicted. In this exemplary embodiment, the electrically-conductive yarn 400 has both cotton fibers 405 and metallic fibers 410. The metallic fibers 410 in this embodiment may be stainless steel, for example. The metallic fibers 410, in this example, may be of very fine gauge, which may facilitate comfort. In FIG. 4B, an exemplary electrically-conductive yarn 415 is depicted. In this exemplary embodiment, the electrically-conductive yarn 415 has both cotton fibers 420 and metallic fibers 425. The metallic fibers 425 in this embodiment may include silver, for example. The metallic fibers 425 in this exemplary embodiment may be coarser than those depicted in FIG. 4A. In figure 4C, a close-up of a silver-impregnated polymer fiber 430 is depicted. The fiber 430 has an interior region 435 and an exterior region 440. The silver has been impregnated into the fiber in such a manner as to render the composition of the exterior region 440 of the fiber 430 relatively high in silver. But the interior region 435 of the fiber 430, in this example, remains relatively low in silver composition. In some embodiments the electrically-conductive fibers may be relatively uniform in metallic composition.
FIG. 5 depicts a close-up of a cross-section of and exemplary ASCRG showing inner liner, adhesive, and outer shell. In this figure, a cross-sectional depiction 500 of an exemplary ASCRG is shown. The inner liner 505 is shown attached to the outer shell 520 via a layer of adhesive 520. The adhesive layer 520 is relatively thin compared with the thickness of the outer shell 515. Within the inner liner 505, silver fibers 510 are depicted in this exemplary embodiment.
Although various embodiments have been described with reference to the Figures, other embodiments are possible. In some embodiments, a mitten-like structure may be created with chemical resistance and anti-static properties. In such an embodiment, both the inner liner and the outer shell may be shaped like mittens. In some embodiments, still other garment types could be made. For example, chemically-resistant aprons may be made with an exterior chemically-resistant shell and an inner liner. In such an embodiment, the electrical conductivity of the apron may inhibit static discharge events.
In various embodiments, apparatus and methods may involve various polymeric compounds for use in forming an exterior shell. For example, some embodiments may use nitrile rubber. Some embodiments may use natural rubber for the outer shell. An exemplary embodiment may use a Fluor rubber, such as Viton to provide for chemical resistance against aromatic hydrocarbons like benzene. Various embodiments may use different anti-static agents in the outer shell. In such embodiments, carbon-black filler may increase the electrical conductivity of the polymeric material. Various embodiments may use metal salts to provide a requisite measure of electrical conductivity. Metal powders may be used in some embodiments. Some embodiments may use graphite as an anti-static agent. And some embodiments may use a combination of two or more anti-static agents. In some applications, various conductive fibers may be used in the inner lining. For example, copper fibers may be used in an inner liner. An inner liner may include carbon fibers in some embodiments. Some exemplary embodiments may use two or more different types of conductive fibers.
In various embodiments the ASCRG may have an electrical connection point to permit a ground connection to the glove. In an exemplary embodiment, a glove may provide an electrical connection point to an electrically-conductive smock or jacket. In accordance with some embodiments, the electrical-connection point may be in the form of a snap, for example. In some applications, a rivet may electrically connect the outer shell of a glove to its inner liner.
In some exemplary embodiments, an ASCRG may have electrostatic dissipative properties. There exist standard tests for determining these electrostatic dissipative properties. An example of such a standard is the prEN 16350:2011 standard, which is titled "Protective Gloves for Electrostatical Risks,". This standard defines the acceptable vertical resistance (that resistance between the exterior of the glove to its interior), in various temperature/humidity conditions. The standard refers to another document as to the testing procedure, EN 1149-2:1997, which is titled "Protective clothing - Electrostatic properties . An exemplary test of the electrostatic dissipative properties of a glove is described in the EN 1149-2:1997 standard, for example, at least with reference to section 7, pages 5, 7, and figures 1-2 of that standard. An exemplary ASCRG may be considered to have successfully passed this test if the measured vertical resistance is less than 1x10⁸ Ohms at 23 degrees Celsius and with 25 percent relative humidity.
An exemplary ASCRG having an outer shell including butyl rubber with carbon-black filler and an inner liner with metal electrically-conductive fibers, for example, may be tested as detailed above for electrostatic dissipative properties. An exemplary ASCRG may substantially have acceptable electrostatic dissipative properties if its vertical resistance is less than 1x10⁸ Ohms at 23 degrees Celsius and 25 percent relative humidity. In some applications even lower vertical resistances may be considered useful or beneficial. In some applications, a measured vertical resistance of less than 1x10⁷ Ohms at 23 degrees Celsius and 25 percent relative humidity may be considered beneficial or safe. In some applications, a measured vertical resistance of less than 1x10⁶ Ohms at 23 degrees Celsius and 25 percent relative humidity may be considered good or necessary, for example.
An exemplary ASCRG may simultaneously have beneficial chemical resistance along with good antistatic discharge properties. For example, an exemplary ASCRG may protect a wearer from exposure to various organic chemicals. By way of example and not limitation, many other chemicals may be handled safely using ASCRGs. Solvents like ketones (e.g. acetone), esters (e.g. ethyl acetate), alcohols (e.g. methanol) and others like acetonitrile, dimethylsulphate, phthalates, phenol, dimethylformamide, ethylene diamine, dimethyl sulphoxide may be handled. Also butyl gloves may protect against acids and bases like concentrated acetic acid, acrylic acid, hydrofluoric acid 40%, methane sufphonic acid, sodium hydroxide, ammonia solution, perchloric acid 70%, and sulphuric acid 96%, for example. Various changes in the relative composition of carbon-black filler in the butyl rubber may provide for improved chemical resistance or improved antistatic discharge properties. Changes may be made in the butyl rubber composition for each dipping step that may be used in the manufacture of the outer shell. In some embodiments, the relative amount of carbon-black filler may change from the inside of the glove to the outside. In such a glove, the chemical protection of the outer shell may be improved while providing for good antistatic discharge properties.
A number of implementations have been described. Nevertheless, it will be understood that various modification may be made. For example, advantageous results may be achieved if the steps of the disclosed techniques were performed in a different sequence, or if components of the disclosed systems were combined in a different manner, or if the components were supplemented with other components. Accordingly, other implementations are within the scope of the following claims.

Claims

An anti-static chemically-resistant glove comprising:
a butyl-rubber outer glove shell having an outer side and an inner side, the butyl-rubber outer glove shell comprising carbon-black filler;

an inner glove liner having an outer side and an inner side, the inner glove liner comprising cotton-yarn containing metal electrically conductive fibers for direct electrical contact with a wearer's skin; and

a water-based acrylic adhesive joining the outer side of the inner glove liner to the inner side of the butyl-rubber outer glove shell;

wherein the anti-static chemically-resistant glove has a vertical resistance of less than 1x10⁸ Ohms at 23 degrees Celsius and 25 percent relative humidity.
The anti-static chemically-resistant glove of claim 1, wherein the vertical resistance of the anti-static chemically-resistant glove is less than 1x10⁷ Ohms at 23 degrees Celsius and 25 percent relative humidity.
The anti-static chemically-resistant glove of claim 1, wherein the vertical resistance of the anti-static chemically-resistant glove is less than 1x10⁶ Ohms at 23 degrees Celsius and 25 percent relative humidity.
The anti-static chemically-resistant glove of claim 1, wherein the metal electrically-conductive fibers comprise stainless steel.
The anti-static chemically-resistant glove of claim 1, wherein the metal electrically-conductive fibers comprise silver.
The anti-static chemically-resistant glove of claim 1, wherein the metal electrically-conductive fibers comprise silver-coated polymer fibers.