Reinforced fingertip disposable glove

Abstract

Elastomeric articles having a reinforcement layer on a portion of the article, and methods of making a multilayered elastomeric article having a reinforcement layer, are provided. The articles, such as gloves, can include a first layer and a reinforcement layer. A reinforced portion of the article includes the first layer and the second layer, and a non-reinforced portion of the article is free of the second layer. The article may be a glove. The reinforcement layer can be provided in the finger region of the gloves. The reinforced portion of the glove can have increased tensile strength, puncture resistance, and chemical resistance compared to the non-reinforced portion.

Description

[0001] REINFORCED FINGERTIP DISPOSABLE GLOVE

[0002] RELATED APPLICATIONS

[0003] The present application claims priority to U.S. Provisional Application Serial No. 63 / 727 ,726, filed on December 4, 2024, which is incorporated herein in its entirety by reference thereto.

[0004] FIELD OF THE INVENTION

[0005] The present invention relates to elastomeric articles, such as gloves, having a reinforced portion that is made from more than one layer of material.

[0006] BACKGROUND OF THE INVENTION

[0007] The development of modern rubber materials has made possible the manufacture of a wide range of elastomeric articles, such as gloves, having varying properties of strength and chemical resistance. Gloves are used as an infection protection device to protect the wearer from exposure to bacteria, viruses, pathogens, infections, diseases, etc. that could transfer from a surface or bodily fluid (e.g., blood) to the wearer’s skin. Gloves are also used in manufacturing environments to prevent the wearer from coming into contact with various chemicals, and in some medical settings, gloves can be used to protect the wearer from certain pharmaceuticals that may be toxic, such as chemotherapy drugs. For users that require gloves for heavier duty tasks, the glove manufacturing solution often results in a glove with an increased thickness profile across the entire glove. However, as the thickness is increased in the palm region and the cuff of the glove, the user may experience a higher level of hand strain during usage, which reduces the ergonomics of the glove. As a result, generally, wearers of elastomeric gloves tend to prefer gloves that are as thin as reasonably possible without compromising the necessary protective benefit, e.g., strength and chemical resistance.

[0008] Whether being used in a medical or manufacturing setting, or for any other use, there is a risk that the gloves could become punctured during use, such as when the gloves are used around sharps such as needles, scissors, blades, hemostats, etc. or equipment used in manufacturing. When such a puncture occurs, the protective barrier provided by the gloves is breached, and the wearer has an increased risk of exposure to bacteria, viruses, pathogens, infections, diseases, etc. The finger region of gloves may most often be breached due to the increased stress on the finger region of the gloves during use, i.e. , as a result of the actions the wearer is performing with their hand.

[0009] It is important that the wearer be made aware of a breach of the protective barrier provided by the gloves, but in most instances, the breach is small (e.g., a puncture, hole, or tear from a small gauge needle), and the wearer may not notice that a breach has occurred. Further, depending on the environment in which the glove is being used, other factors may make the breach difficult to see. For example, the lighting may be poor, or the glove may be soiled or otherwise altered in appearance, making a small puncture nearly impossible to see. Moreover, while twolayered gloves have been available for use, one of the two layers is typically white, which is accomplished by simply adding titanium dioxide to one of the layers. Because one of the layers is white, breach detection is difficult, particularly in industrial and manufacturing settings, where the wearer of the glove may come in contact with many hazardous materials. Thus, the wearer might not be aware or alerted to the fact that the glove has been breached upon seeing a whitish color present on the glove. Further, the environment surrounding the wearer may include walls, countertops, equipment, lighting, etc. that are white in color or that accentuate a white color, making it difficult for the wearer to discern a visual cue on a white glove.

[0010] Moreover, even when existing multilayer elastomeric gloves may include contrasting colors to enable breach detection, the existing multilayer elastomeric gloves do not visually indicate to a user that the glove exhibits improved strength or reinforcement. Instead, existing multilayer elastomeric gloves do not include any visual characteristics, particularly on the grip side of the glove, to indicate that the glove has been reinforced to improve the strength, puncture resistance, chemical resistance, or other physical properties of the glove.

[0011] As such, a need exists for a glove that has increased strength and chemical resistance at the fingers without compromising ergonomics of the glove. In particular, a glove with increased strength at the fingers which also enables quick identification of punctures, holes, tears, etc. would be beneficial. SUMMARY OF THE INVENTION

[0012] In one aspect of the invention, an elastomeric glove is provided. The glove includes a first layer and a second layer. The first layer includes a first elastomeric material comprising nitrile rubber. The second layer defines a reinforcement layer of the glove and includes a second elastomeric material comprising nitrile rubber. The glove includes a reinforced portion including the first layer and the second layer, and a non-reinforced portion that is free of the second layer. The glove includes a finger region, a palm region, and a cuff region, wherein the non-reinforced portion is spaced apart from the finger region.

[0013] In accordance with aspects of the present disclosure, the finger region is comprised of the reinforced portion.

[0014] In accordance with aspects of the present disclosure, the glove comprises a donning side and a grip side opposite the donning side, and the second layer is disposed on the grip side of the glove.

[0015] In accordance with aspects of the present disclosure, the glove comprises a donning side and a grip side opposite the donning side, and the second layer is disposed on the donning side of the glove.

[0016] In accordance with aspects of the present disclosure, a thickness of the finger region is greater than a thickness of the cuff region.

[0017] In accordance with aspects of the present disclosure, the finger region has a thickness in a range from about 0.1 mm to about 0.50 mm.

[0018] In accordance with aspects of the present disclosure, the cuff region has a thickness in a range from about 0.05 mm to about 0.40 mm.

[0019] In accordance with aspects of the present disclosure, the first elastomeric material and the second elastomeric material are distinct.

[0020] In accordance with aspects of the present disclosure, the first elastomeric material and the second elastomeric material each comprise acrylonitrile, wherein the first elastomeric material and the second elastomeric material comprise unequal content of acrylonitrile by weight.

[0021] In accordance with aspects of the present disclosure, the second elastomeric material comprises a higher acrylonitrile content by weight than the first elastomeric material. In accordance with aspects of the present disclosure, the acrylonitrile content of the second elastomeric material is in a range from about 30 wt. % to about 60 wt. %.

[0022] In accordance with aspects of the present disclosure, the second material has a higher modulus of elasticity than the first material.

[0023] In accordance with aspects of the present disclosure, the reinforced portion has a higher tensile strength than the non-reinforced portion.

[0024] In accordance with aspects of the present disclosure, the reinforced portion has higher puncture resistance than the non-reinforced portion.

[0025] In accordance with aspects of the present disclosure, a breach of the reinforced section exposes a distinct colored pigment of the first layer or the second layer to facilitate detection of the breach.

[0026] In accordance with aspects of the present disclosure, the elastomeric article is reversible.

[0027] The present invention is further directed to a method of making a multilayered elastomeric article. The method includes a step of dipping a mold a first depth into a first solution comprising a first powder free coagulant, wherein the first powder free coagulant includes a first metallic salt, wherein the first metallic salt is present in an amount ranging from about 10 wt.% to about 30 wt.% based on the total wt.% of the first solution. The method includes a step of dipping the mold the first depth into a first elastomeric formulation comprising a first elastomeric material to form a first layer, wherein the first elastomeric material comprises acrylonitrile. The method includes a step of dipping the mold a second depth into a second solution comprising a second powder free coagulant, wherein the second powder free coagulant includes a second metallic salt, wherein the second metallic salt is present in an amount ranging from about 10 wt.% to about 30 wt.% based on the total wt.% of the second solution. The method includes a step of dipping the mold a second depth into a second elastomeric formulation comprising a second elastomeric material to form a second layer, wherein the second elastomeric material comprises acrylonitrile. The method includes a step of curing the first elastomeric formulation and the second elastomeric formulation to form the reinforced elastomeric article. In the method, the first depth is not equal to the second depth.

[0028] In aspects of the method of the present disclosure, the first depth is less than the second depth. In aspects of the method of the present disclosure, the first depth is greater than the second depth.

[0029] In aspects of the method of the present disclosure, the first metallic salt in the first solution and the second metallic salt in the second solution include nitrate, sulfate, or chloride salts of calcium, aluminum, or zinc, or a combination thereof.

[0030] In aspects of the method of the present disclosure, the first solution, the second solution, or both further comprise a wax, a hydrogel, a silicone, a gel, an inorganic powder, an antimicrobial agent, an acrylic polymer, a peroxide crosslinking agent, an emollient, a hydrophilic agent, a hydrophobic agent, a pigment, a colorant, a dye, a polyolefin-based powder, a surfactant, a soap, an acidic agent, an alkali agent, or a combination thereof.

[0031] In aspects of the method of the present disclosure, the first elastomeric material and the second elastomeric material comprise unequal content of acrylonitrile by weight.

[0032] In aspects of the method of the present disclosure, the second elastomeric material comprises a higher acrylonitrile content by weight than the first elastomeric material.

[0033] In aspects of the method of the present disclosure, the elastomeric article is a glove, further wherein either the first layer or the second layer forms a reinforcement layer on a partial portion of the glove.

[0034] In aspects of the method of the present disclosure, a finger region of the glove includes the reinforcement layer.

[0035] In aspects of the method of the present disclosure, a cuff region of the glove is free from the reinforcement layer.

[0036] In aspects of the method of the present disclosure, the reinforcement layer is present on a grip side of the glove.

[0037] In aspects of the method of the present disclosure, the reinforcement layer is present on a donning side of the glove.

[0038] Additional features and advantageous of the present invention will be revealed in the following detailed description. Both the foregoing summary and the following detailed description and examples are merely representative of the invention, and are intended to provide an overview for understanding the invention as claimed. BRIEF DESCRIPTION OF THE FIGURES

[0039] A full and enabling disclosure of the present invention to one skilled in the art, including the best mode thereof, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

[0040] FIG. 1 illustrates a grip side of a multilayered glove in accordance with embodiments of the present disclosure;

[0041] FIG. 2 illustrates a donning side of a multilayered glove in accordance with embodiments of the present disclosure;

[0042] FIG. 3 illustrates a method of forming the multilayered glove according to embodiments of the present disclosure;

[0043] FIG. 4 illustrates a grip side of a glove in accordance with embodiments of the present disclosure;

[0044] FIG. 5 illustrates a donning side of a glove in accordance with embodiments of the present disclosure; and

[0045] FIG. 6 illustrates a method of forming a multilayered glove in accordance with embodiments of the present disclosure.

[0046] DETAILED DESCRIPTION

[0047] Reference now will be made in detail to various embodiments of the invention, one or more examples of which are set forth below. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

[0048] Generally speaking, the present invention describes the creation of elastomeric articles, such as gloves, made from more than one layer such that a second or subsequent layer provides reinforcement to a portion of the elastomeric article. For instance, a first layer of the article, e.g., glove, can form a full body of the article. A full body of a glove may include a finger region, palm region, and cuff region. A second layer of the article may be formed at only one portion of the article. For instance, the second layer may be formed at only one portion of the glove. A reinforced portion of the article may include both the first layer and the second layer. A non-reinforced portion of the article is free of the second layer. When the article is a glove, the finger region may be comprised of the reinforced portion to provide reinforcement to the finger region. In some embodiments, the first layer can form a grip side layer, and the second layer can be provided on the donning side of the glove. In some embodiments, the first layer can form a donning side of the glove, and the second layer can be provided on the grip side of the glove.

[0049] In some aspects of the present invention, the glove can include a first layer and a reinforcement layer in which a colorant is compounded or integrated. Further, in some embodiments, the first layer can include a first colorant compounded or integrated therein, and the second layer can include a second colorant compounded or integrated therein. In some aspects of the invention, the glove can include a translucent first layer, and a second layer in which a colorant is compounded or integrated, where the term translucent means allowing the passage of light, but not allowing objects beyond to be clearly seen while allowing contrasts to be seen. Any of the contemplated arrangements can enable a breach of the grip side layer to be more easily detected, either due to the high level of contrast between the first layer and the reinforcement layer when a first colorant and a second colorant are utilized, or due to the translucence of the first layer as compared to the reinforcement layer, where the intensity of the reinforcement layer is increased upon a breach of the translucent layer.

[0050] As shown in FIGS. 1 and 2, the elastomeric glove 101 may include a finger region 105 generally including each of the four fingers and thumb of the glove, a palm region 106 generally including the palm and dorsal side of the hand of the glove, and a cuff region 103 at an end of the glove opposite the finger region 105. In particular, the finger region 105 may include the portion of the glove 101 from the fingertips 108 to the knuckle portions 109 of the fingers and thumb. A grip side 102 of the glove 101 may be exposed on an outer side of the glove 101. The grip side 102 may include each of the finger region 105, the palm region 106, and the cuff region 103. A donning side 107 of the glove 101 is disposed opposite the grip side of the glove 101 , e.g., configured to contact a wearer’s hand when the glove is donned.

[0051] The glove 101 includes a first layer of elastomeric material 110. In some aspects, first layer of elastomeric material 110 may form part of the finger region 105, the palm region 106, and the cuff region 103 of the glove 101. In some aspects, the first layer of elastomeric material 110 may form at least a portion of the grip side 102 and at least a portion of the donning side 107 of the glove 101.

[0052] At least a portion of the glove 101 includes a second layer of elastomeric material 112 forming a reinforcement layer. A reinforced portion of the glove 101 is formed from both the first layer of elastomeric material 110 and the second layer of elastomeric material 112. A non-reinforced portion of the glove 101 is free from the second layer of elastomeric material.

[0053] For instance, to reinforce the finger region 105 of the glove to improve the physical properties in the finger region 105, the finger region 105 may be formed from the reinforced portion of the glove 101. In other words, the finger region 105 may include both the first layer of elastomeric material 110 and the second layer of elastomeric material 112.

[0054] In some aspects of the present invention, the second layer of elastomeric material 112 may form at least a portion of the donning side 107. For instance, the second layer of elastomeric material 112 may form the donning side 107 of the reinforced portion of the glove 101. As illustrated in FIG. 2, the reinforced portion may form the donning side 107 the finger region 105 of the glove 101 .

[0055] In some aspects of the present invention, as illustrated in FIGS. 3 and 4, the second layer of elastomeric material 112 may form at least a portion of the grip side 102. For instance, the second layer of elastomeric material 112 may form the grip side 102 of the reinforced portion of the glove 101 . As illustrated in FIG. 5, the reinforced portion may form the grip side 102 the finger region 105 of the glove 101.

[0056] In some aspects of the present invention, the first elastomeric material 110 and the second elastomeric material 112 can have a high color contrast or intensity difference in order to facilitate breach detection. In other words, the first elastomeric material 110 and the second elastomeric material 112 can have a sufficient level of color contrast so that a breach of the outer layer or grip side layer 102 in the reinforced portion of the glove 101 can be easily detected since the contrasting color of the donning side 107 in the reinforced portion can be visible through the breach (e.g., puncture or tear) of the grip side layer 102.

[0057] As shown in FIG. 5, when the second layer of elastomeric material 112 is disposed on the grip side 102 of the glove 101 , the contrast between the colors of the first layer of elastomeric material 110 and the second layer of elastomeric material 112 may be visible. In this manner, the reinforced portion and the nonreinforced portion of the glove 101 may be visually distinct.

[0058] In addition, as a result of the specific components of each of the glove layers (e.g., the first elastomeric material 110 and the second elastomeric material 112) and the processing conditions (e.g., dip times, coagulant concentrations, specific polymer formulations, etc.) by which the glove is made, the glove 101 can be reinforced at the reinforced section, while the glove can still be thin enough to maximize user comfort, enhance tactile sensitivity to temperature and surface textures, and reduce manufacturing time and cost. The reinforced section may be disposed where the glove 101 is most vulnerable to breaches or punctures during use. For instance, the reinforced section may be disposed at the finger region 105 of the glove 101 . In some aspects, the reinforced section 101 may include only the fingertips of the finger region 105, or any other fraction of the finger region 105 extending from the fingertips toward the palm region 106. In some aspects, the reinforced section may include an entirety of the finger region 105. In some aspects, the reinforced section may additionally include at least a portion of the palm region 106 of the glove 101 adjacent to the finger region 105. Further, the glove layers can have sufficient color contrast without “bleeding” or “muddying” of the darker color associated with one of the layers through the other lighter colored layer.

[0059] The reinforced section of the glove 101 of the present disclosure may have a thickness greater than a thickness of the non-reinforced section of the glove 101. For instance, a glove made according to the present invention can have a reinforced section thickness ranging from about 0.1 millimeters to about 0.5 millimeters, such as from about 0.15 millimeters to about 0.35 millimeters, such as from about 0.20 millimeters to about 0.27 millimeters. Further, the non-reinforced portion of the glove can have a thickness ranging from about 0.03 millimeters to about 0.5 millimeters, such as from about 0.06 millimeters (mm) to about 0.15 millimeters, such as from about 0.07 mm to about 0.14 mm, such as from about 0.08 millimeters to about 0.13 mm. In general, the finger region 105 thickness of the glove 101 may be greater than the cuff region 103 thickness of the glove 101. Moreover, when the palm region 106 is formed from the non-reinforced portion of the glove, the finger region 105 thickness may be greater than the palm region 106 thickness of the glove 101 .

[0060] Moreover, the glove 101 can have a length ranging from about 200 mm to about 625 mm, such as from about 220 mm to about 450 millimeters, such as from about 230 mm to about 260 mm, such as from about 235 mm to about 255 mm, such as from about 240 mm to about 250 mm. Additionally, the glove 101 can have a weight ranging from about 5 grams (g) to about 9 g, such as from about 6 g to about 8 g, such as from about 6.5 g to about 7.5 g.

[0061] Various glove layer components, glove formation procedures, and several examples contemplated by the present invention are discussed in more detail below. I. Glove Lavers

[0062] The glove of the present invention may generally be formed from any of a variety of natural and / or synthetic elastomeric materials known in the art. For instance, some examples of suitable elastomeric materials include, but are not limited to, nitrile rubbers (e.g., acrylonitrile butadiene), polyurethanes, S-EB-S (styrene-ethylene-butylene-styrene) block copolymers, S-l-S (styrene-isoprene- styrene) block copolymers, S-B-S (styrene-butadiene-styrene) block copolymers, S-l (styrene-isoprene) block copolymers, S-B (styrene-butadiene) block copolymers, natural rubber latex, isoprene rubbers, chloroprene rubbers, neoprene rubbers, polyvinyl chlorides, silicone rubbers, and various combinations thereof.

[0063] In one aspect, the first layer of the glove, the second layer of the glove, or both can be formed from a nitrile rubber. Various components of possible nitrile rubber formulations contemplated by the present invention are discussed in more detail below, although it is to be understood that the nitrile rubber can be substituted for any other suitable elastomeric material, such as those mentioned above.

[0064] A. Nitrile Rubber Formulation

[0065] The nitrile rubber that can be used to form one of the layers can include a carboxylated nitrile that is compounded with various components based on 100 parts of the carboxylated nitrile. The carboxylated nitrile rubber and the various components compounded with the nitrile rubber in the formulation of the present invention are discussed in more detail below.

[0066] Carboxylated nitrile, which is a terpolymer of butadiene, acrylonitrile, and organic acid monomers, has at least two properties that make it useful for manufacturing elastomeric articles. These two features are high strength and impermeability to certain hydrocarbon solvents and oils. Compounding and curing the rubber with other ingredients such as curing agents, optional accelerators, and activators is generally performed to optimize these properties. The level of each monomer in the polymer and the level of curing can affect the levels of strength and the chemical resistance in the finished article. Polymers with higher levels of acrylonitrile tend to have better resistance to aliphatic oils and solvents, but are also stiffer than polymers that have lower levels of acrylonitrile. While the chemical nature of the monomers from which the polymer is made offers some degree of chemical resistance, when the polymer molecules are chemically crosslinked, resistance to chemical swelling, permeation, and dissolution greatly increase.

[0067] The base polymer employed in the nitrile rubber can be a random terpolymer composition containing acrylonitrile, butadiene, and carboxylic acid components. It is believed that the particular advantageous properties of the present soft nitrile rubber materials can be due in part to the nature and interaction of a blend of acrylonitrile components in the composition. The blend can include two - a first and a second - acrylonitrile formulations in a compositional ratio ranging, respectively, from about 60:40 to 40:60. The orientation or placement of carboxyl groups on the nitrile polymer molecules - either outside or inside - can affect the reactivity of the carboxyl groups with zinc ions; hence, it is believed that some components exhibit softer, lower modulus properties and some components have good film forming properties.

[0068] The acrylonitrile content of the blended or combined terpolymer composition can range from about 10% by weight to about 60% by weight. In one embodiment, for instance, the acrylonitrile content can be between about 10% by weight and about 60% by weight, the methacrylic acid content can be less than about 10% by weight, and the remainder of the polymer can be butadiene. The methacrylic acid content should be less than about 15% by weight, preferably about 10% by weight, with butadiene making up the remainder balance of the polymer. The base terpolymer is made through a process of emulsion polymerization, and can be used while still in emulsion form to manufacture gloves or other elastomeric articles.

[0069] The acrylonitrile content of the composition influences the physical and chemical resistance properties of the elastomeric article, e.g., glove. Articles with a lower percentage of acrylonitrile are more flexible and comfortable but offer less chemical resistance as compared to articles with a higher percentage of acrylonitrile. For instance, lower-ACN articles may have a softer feel. In this regard, relatively lower ACN gloves may have improved comfort and tactile sensitivity, making them suitable for tasks requiring high dexterity. However, an article with higher acrylonitrile content may have increased strength, e.g., tensile strength, and puncture resistance, as compared to lower-ACN articles. Additionally, acrylonitrile provides a chemical barrier, so relatively higher ACN articles may have increased resistance to nonpolar solvents, oils, and fuels.

[0070] In some aspects of the present invention, the first elastomeric material may have a different acrylonitrile content (ACN) than the second elastomeric material, e.g., used to form the second or reinforcement layer. For instance, the first elastomeric material may have a lower acrylonitrile content than the second elastomeric material. In this manner, the first elastomeric material may be a “softer” material, e.g., having a lower modulus of elasticity, while the second elastomeric material may be a stiffer material, e.g. , having a higher modulus, as a result of the ACN of each respective formulation. For instance, the first elastomeric material ACN may range from about 10% by weight (wt. %) to about 40% by weight (wt. %), such as from about 12% by weight to about 28% by weight, such as from about 15% by weight to about 25% by weight. The second elastomeric material ACN may range from about 30% by weight (wt. %) to about 60% by weight (wt. %), such as from about 35% by weight to about 55% by weight, such as from about 40% by weight to about 50% by weight. The present inventors have further found that the higher ACN of the second elastomeric material can achieve a higher tensile strength, resulting in improved puncture resistance, along with improved chemical permeation resistance to solvents. Moreover, the present inventors have found that the combination of a relatively lower ACN first layer with a relatively higher ACN second layer to form the reinforced portion of the glove can achieve a glove having improved physical strength and chemical resistance portion of the glove most vulnerable to breaches and punctures during use, e.g., the finger region 105, without sacrificing the flexibility, comfort, and dexterity of the glove as a whole.

[0071] Further, the acrylonitrile polymer formulations that may be employed in the present invention can have a glass transition temperature (Tg) ranging from about -30°C to about -10°C, such as from about -28°C to about -12°C. In some embodiments, desirable nitrile polymer formulations, such as PolymerLatex X-1133 or Synthomer 6311 available from PolymerLatex GmbH, and Synthomer Ltd., respectively, can have a Tgbetween about -26°C and about -18°C. Other nitrile formulations, such as Nantex® 635t, commercially available from Nantex Industry Co., Ltd. (Taiwan, R.O.C.), can have a Tgbetween about -25.5°C and about -23.4°C. Another suitable nitrile polymer contemplated for use in the elastomeric articles of the present invention is Lutex 111 manufactured by LG Chem, which has a Tgranging from about -22°C to about -14°C and a total solids content of about 44.5% to about 45.5% and a pH of from about 8.2 to about 8.8.

[0072] It is believed, however, that the nitrile butadiene polymer properties do not come from components of the nitrile material, but from the structure of the polymer, which in turn, is determined by polymerization conditions. Polymer properties are very much affected by the polymer structure. Molecular structure of polymers can be very complex, with variability in molecular weight, molecular weight distribution, amount of branching, amount of crosslinking during polymerization, many possible types of chemical addition for diene monomers, etc. When several monomer types are combined into a polymer such as in a carboxylated acrylonitrile butadiene polymer used for glove manufacture, the structure becomes even more complex. Overall levels of each monomer type and the sequencing of the monomer units also contribute to the properties of the resulting polymer. When the repeating structure of the monomer units is random, such as in the nitrile rubber used for gloves, the physical properties of the polymer have increased influence from the polymer linearity (vs. branching) and molecular weight as compared to the properties of a homopolymer. This is because the properties expected from a regular repeating structure of a polymer made only from each single monomer change once that repeating structure is interrupted or otherwise altered by the addition of other types of monomer units. A high level of any particular monomer will likely increase the chance of contributing properties expected from a homopolymer made from that monomer, due to increased similarity of the repeating structures.

[0073] In carboxylated nitrile rubber used for thin glove manufacture, the acrylonitrile and carboxylic acid, which typically total approximately 35% by weight, add some plastic like character to the polymer with respect to resilience, permanent set, and stress relaxation. They also prevent a regular cis-1 ,4 repeating structure that would give polybutadiene its highest resilience and lowest set / relaxation.

[0074] A general description of such a carboxylated nitrile rubber would be a long- chain random arrangement of its three component monomers, with branching and crosslinking. These branched, random terpolymers are former into discrete tiny particles that are emulsified in water. In addition to the polymer structure, the particle structure also plays a part in the final properties of a glove. Parameters such as particle size, particle size distribution, level of particle agglomeration, particle density, etc., affect how the product is formed, and also its eventual properties.

[0075] Although not required, the polymer structure can include a random terpolymer (as opposed to block or alternating terpolymer) of acrylonitrile, butadiene, and carboxylic acid. The properties depend on the average molecular weight, the molecular weight distribution, the linearity or degree of branching, the gel content (crosslinking during polymerization), and the microstructure (which monomer units are next to each other in short sections of the polymer chain).

[0076] Regardless of the particular structure of the nitrile rubber that can be used in one or more layers of the glove of the present disclosure, various additional components can be incorporated during the compounding of the nitrile rubber formulation so that the overall glove can have certain desired properties.

[0077] For instance, an alkali agent can be added to the nitrile rubber formulation to adjust the pH of the nitrile rubber formulation. Any suitable alkali agent can be used, and, in some embodiments, the alkali agent can be potassium hydroxide, ammonium hydroxide, or a combination thereof. In any event, the alkali agent can be used to adjust the nitrile rubber formulation to a pH that can range from about 9 to about 11 , such as from about 9.2 to about 10.5, such as from about 9.5 to about 10.2. In addition to acting as a pH adjuster, the alkali agent can be utilized in combination with a metal oxide as discussed below to facilitate the formation of a nitrile rubber formulation that has high strength. Specifically, the alkali agent can include monovalent ions, such as K, Na, or H, which, although they do not have sufficient electron capacity to accommodate a bond with a second methylacrylic acid unit, may allow for weaker forms of associative bonding. As such, the alkali agents (e.g., monovalent salts) that can be used to increase the pH of the nitrile rubber formulation may also swell the nitrile rubber particles, making more carboxylic acid groups accessible to other crosslinking agents, such as the metal oxides discussed in more detail below. The positive charge of the cation can well balance the negative electrons of the acidic carboxyl groups.

[0078] Regardless of the particular alkali agent utilized, the alkali agent can be present in the compounded nitrile rubber formulation in an amount ranging from about 0.1 parts to about 2 parts, such as from about 0.25 parts to about 1.75 parts, such as from about 0.5 parts to about 1 .5 parts, based on 100 dry parts of the nitrile rubber. Further, the nitrile rubber formulation that can be used in one or more layers of the elastomeric glove of the present invention can be chemically crosslinked to enhance the elasticity, strength, and chemical resistance of the nitrile rubber formulation. Crosslinking can be accomplished in at least two ways: the butadiene subunits can be covalently crosslinked with sulfur and accelerators, while the carboxylated (organic acid) sites can be ionically crosslinked with metal oxides or salts. Ionic crosslinks, resulting from, for example, the addition of a metal oxide, such as zinc oxide, to the nitrile rubber formulation, can result in a nitrile rubber formulation having high tensile strength, puncture resistance, and abrasion resistance, as well as high elastic modulus (a measure of the force required to stretch a film of the rubber), but poor oil and chemical resistance, which is why a sulfur crosslinking agent can be added to the nitrile rubber formulation, as discussed in more detail below.

[0079] Including a metal oxide, such as zinc oxide, in the nitrile rubber formulation can improve the dipping qualities and cure rates of the formulation. In contrast, when zinc oxide is not employed, the curing time required to reach an optimum state of cure can be much longer and the curing may be less efficient. This means that the crosslinks are longer (more sulfur atoms per crosslink) and there may be a higher amount of sulfur that does not crosslink polymer chains. The result can be a less- effectively cured rubber that has lowered heat resistance and less chemical resistance.

[0080] While not intending to be bound by theory, it is believed that the matrix structure and strength of the nitrile rubber formulation that can be used in one or more layers of the glove of the present invention may result from the interaction of all ions present in the system, in particular, divalent or higher valence cations, with the carboxylic acid components of the polymer matrix. Divalent or multivalent cations, such as Mg, Ca, Zn, Cu, Ti, Cd, Al, Fe, Co, Cr, Mn, and Pb, can crosslink with the carboxyl groups of the ionized carboxylic acids, forming relatively stable bonds. Of these cation species, Mg, Ca, Zn, Cu, or Cd are more desirable. Preferably, the methylacrylic acid monomers are located relatively close to each other in the polymer matrix structure; in such a fashion, the divalent or multivalent cation can crosslink with two or more nearby acid units. The positive charge of the cation can well balance the negative electrons of the acidic carboxyl groups. It is believed that, absent divalent or multivalent cations, multiple polymer chains in the nitrile emulsions are not well crosslinked together.

[0081] Regardless of the particular metal oxide utilized, the metal oxide can be present in the compounded nitrile rubber formulation in an amount ranging from about 0.1 parts to about 2 parts, such as from about 0.25 parts to about 0.4 parts, such as from about 0.08 parts to about 0.3 parts, based on 100 dry parts of the nitrile rubber.

[0082] In some aspects, a sulfur crosslinking agent can also be used in the nitrile rubber formulation to provide oil and chemical resistance to a layer of a glove containing the formulation. Such crosslinking can provide resistance to chemical swelling, permeation, and dissolution. In contrast to the alkali agent and metal oxide crosslinking agents discussed above, the sulfur is used to covalently crosslink the butadiene subunits of the carboxylated nitrile rubber.

[0083] Sulfur can be present in the compounded nitrile rubber formulation in an amount ranging from about 0.1 parts to about 5 parts, such as from about 0.2 parts to about 2.5 parts, such as from about 0.5 parts to about 2 parts, based on 100 dry parts of the nitrile rubber.

[0084] A vulcanization accelerator can be used in combination with the sulfur crosslinking agent to provide the desired level of chemical resistance to the nitrile rubber formulation. As with the sulfur crosslinking agent, the vulcanization accelerator can be used to covalently crosslink the butadiene subunits of the carboxylated nitrile rubber. The vulcanization accelerator can be a single dithiocarbamate accelerator that is added with sulfur. However, in other cases where higher levels of chemical resistance are needed, a combination of vulcanization accelerators can be utilized. Such a combination can include a dithiocarbamate, a thiazole, and a guanidine compound, which can be present according to a ratio of about 1 :2:2. For example, the vulcanization accelerator can be zincediethyldithiocarbamate (ZDEC), zinc mercaptobenzothiazole (ZMBT), diphenyl guanidine (DPG), or a combination thereof.

[0085] Regardless of the particular vulcanization accelerator or combination of vulcanization accelerators utilized, the vulcanization accelerator can be present in the compounded nitrile rubber formulation in an amount ranging from about 0.1 parts to about 5 parts, such as from about 0.2 parts to about 2.5 parts, such as from about 0.5 parts to about 2 parts, based on 100 dry parts of the nitrile rubber. In one particular embodiment, the compounds can be zincdiethyldithiocarbamate (ZDEC), zinc mercaptobenzothiazole (ZMBT), and diphenyl guanidine (DPG), at about 0.25 parts ZDEC, 0.5 parts ZMBT, and 0.5 parts DPG, based on 100 dry parts of nitrile rubber. In another particular embodiment, the compounds can be zincdiethyldithiocarbamate (ZDEC), zinc mercaptobenzothiazole (ZMBT), and diphenyl guanidine (DPG), at about 0.25 parts ZDEC, 0.25 parts ZMBT, and 0.5 parts DPG, based on 100 dry parts of nitrile rubber.

[0086] Alternatively, the compounded nitrile rubber formulation may be sulfur and / or accelerator-free. Accelerators are compounds sometimes included in a compounded nitrile rubber formulation for use in facilitating vulcanization of the elastomeric material. However, the presence of sulfur and / or accelerators may cause an adverse reaction in users of articles formed from an elastomeric material including sulfur and / or accelerator(s). The reaction is commonly referred to as a Type IV allergy, which generally occurs within 6 to 48 hours of contact with the article and that is localized to the area of the skin where contact is made. Preparing a compounded nitrile rubber formulation for use in fabricating the first layer or second layer of elastomeric material that is accelerator-free may facilitate reducing or substantially eliminating adverse reactions to a user donning the glove 101 .

[0087] Moreover, the nitrile rubber formulation of one of the first layer or second layer of elastomeric material can include one or more of a titanium dioxide or similar filler, a color pigment, or a combination thereof to provide a desired level of color, contrast, brightness, saturation, value, and / or opaqueness. Specifically, the compounded nitrile rubber formulation can include titanium dioxide or any other similar filler in an amount ranging from about 0.25 parts to about 30 parts, such as from about 0.5 parts to 15 parts, such as from about 0.75 parts to about 10 parts, based on 100 dry parts of the nitrile rubber. Without intending to be limited by any particular theory, the present inventors have found that the inclusion of titanium dioxide or any other similar filler in such amounts can prevent the bleed through of color pigments between the various layers of the glove. Further, if utilized as the reinforcement layer of the elastomeric glove of the present invention, the compounded nitrile rubber formulation can include a lighter colored pigment (e.g., red, orange, yellow, green, blue, indigo, violet, or a combination thereof) in an amount ranging from about 0.5 parts to about 15 parts, such as from about 0.5 parts to about 12.5 parts, such as from about 0.6 parts to 9 parts, such as from about 0.8 parts to about 8 parts, based on 100 dry parts of the nitrile rubber. Moreover, the present inventors have discovered that the ratio of the parts of titanium dioxide to the colored pigment in the reinforcement layer of the formulation (e.g., nitrile rubber) can be controlled to achieve a reinforcement layer having sufficient value and saturation percentages as discussed above. Specifically, the ratio of parts of titanium dioxide to the parts of colored pigment in the reinforcement layer formulation can range from about 0.25 to about 3, such as from about 0.3 to about 2.75, such as from about 0.75 to about 2.5, such as from about 1 to about 2. It should be understood, however, that in some embodiments, the compounded nitrile rubber formulation used as the reinforcement layer of the elastomeric glove can include titanium dioxide in the amounts described above without the inclusion of an additional colored pigment. It should also be understood that in some embodiments, the layer described as the reinforcement layer can form the grip side layer and vice versa.

[0088] Meanwhile, the compounded nitrile rubber formulation of the other of the first layer of elastomeric material and the second layer of elastomeric material can include a darker colored pigment (e.g., black, brown, dark gray, blue, purple, etc.) in an amount ranging from about 0.25 parts to about 5 parts, such as from about 0.5 parts to about 4 parts, such as from about 0.75 parts to about 3 parts, based on 100 dry parts of the nitrile rubber.

[0089] It is to be understood that the formulation used to form the second or reinforcement layer of the glove can alternatively be used to form the grip side layer of the glove or the donning side layer of the glove, and the formulation used to form the first layer of the glove can alternatively be used to form the donning side layer of the glove or the grip side layer of the glove, where breach detection can still be determined due to the contrast in color between the layers.

[0090] Regardless of the specific components utilized to form the formulations of the present invention, after compounding, the resulting formulations can have a total solids content (TSC) of from about 10% to about 40%.

[0091] For instance, the formulation for the first elastomeric material can have a TSC of from about 20% to about 45%, such as from about 25% to about 40%, such as from about 30% to about 35%. Further, formulation for the second elastomeric material can have the same TSC as the first elastomeric material. In other aspects of the invention, the formulation for the second elastomeric material can have a TSC of from about 10% to about 25%, such as from about 12% to about 20%, such as from about 13% to about 18%. The present inventors have found that the total solids content of the formulation for the first elastomeric material can enable the glove to have a suitable thickness in the palm region and cuff region with only a single dip, as will be described in further detail below.

[0092] After the rubber formulations are compounded, the formulations can be used to form various layers of any suitable elastomeric article. In one particular embodiment, nitrile rubber formulation can be used to form a glove having multiple layers to provide reinforcement to the finger region and further facilitate breach detection, as discussed in more detail below.

[0093] II. Glove Formation

[0094] After the various glove layer formulations (e.g., the nitrile rubber formulations or formulations formed from any other suitable materials) are compounded, the formulations can be used in a coagulant dip-coating process to form an elastomeric glove. Although any suitable materials can be utilized to form the glove, in one particular embodiment, both the first layer and the second or reinforcement layer can be formed from nitrile rubber. For simplicity, the following glove forming dip processes are described in terms of the formation of a glove having a nitrile rubber first layer and a nitrile rubber second layer.

[0095] As shown in FIG. 3, in one embodiment, a four-dip process is contemplated that includes steps 302, 304, 306, 308, and 310. The process for forming an elastomeric glove entails providing a clean glove form or mold that can be preheated to approximately 55-60°C, and preferably about 58°C.

[0096] In step 302, the prepared mold is then dipped into a first coagulant solution (e.g., an aqueous solution) comprising a first powder free coagulant that includes one or more metallic salts (e.g., nitrate, sulfate, or chloride salts of calcium, aluminum, or zinc, or a combination thereof). In one particular embodiment, the metallic salt may include calcium nitrate.

[0097] The dip time of step 302 for the first coagulant solution can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 10 seconds and 30 seconds is desirable. For instance, the dip time can be about 16 seconds.

[0098] The metallic salts can be present in the first coagulant solution in an amount ranging from about 3 wt.% to about 15 wt.%, such as from about 6 wt.% to about 14 wt.%, such as from about 8 wt.% to about 12 wt.% based on the total weight of the solution.

[0099] In addition to a first powder free coagulant, the solution in step 302 can include one or more other components. For instance, the solution can include a wax, a hydrogel, a silicone, a gel, an inorganic powder (e.g., carbonates, stearates, oxides, hydroxides, aluminates, etc.), an antimicrobial agent (e.g., silver (Ag++), copper (Cu++), polyhexamethylene biguanide (PHMB), etc.), an acrylic polymer, a peroxide crosslinking agent, an emollient (e.g., shea butter, petroleum, etc.), a hydrophilic agent, a hydrophobic agent, a pigment, a colorant, a dye, a polyolefin- based powder (e.g., a polyethylene powder or a polypropylene powder), a surfactant, a soap, an acidic agent, an alkali agent, or a combination thereof. These additional components can be present in the solution in an amount ranging from about 0.1 wt.% to about 30 wt.%, such as from about 0.5 wt.% to about 25 wt.%, such as from about 1 wt.% to about 20 wt.% based on the total weight of the solution.

[0100] In step 304, the mold, with the first powder free coagulant on its surface, is dried and reheated to approximately 70°C ±5°C, and dipped into a bath of a first formulation (e.g., the compounded nitrile rubber formulation of the first elastomeric material) to form a first layer (e.g., the grip side layer) of a gelled glove. The dip time for the first formulation can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 15 seconds and 30 seconds may be desirable. For instance, the dip time may be about 23 seconds.

[0101] Then, in step 306, the mold with the first layer coated thereon is dipped into a second coagulant solution (e.g., an aqueous solution) comprising a second powder free coagulant that includes one or more metallic salts (e.g., nitrate, sulfate, or chloride salts of calcium, aluminum, or zinc, or a combination thereof). In particular, in step 306, the mold is dipped to a level that does not cover the cuff portion of the mold. For instance, in step 306, the mold may be dipped to a level that covers the knuckle portion of fingers and thumb of the mold, i.e. , dipped only for the finger region. In one particular embodiment, the metallic salt may include calcium nitrate.

[0102] The dip time of step 306 for the second coagulant solution can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 10 seconds and 30 seconds is desirable. For instance, the dip time can be about 18 seconds. The metallic salts can be present in the second coagulant solution in an amount ranging from about 3 wt.% to about 22 wt.%, such as from about 4 wt.% to about 21 wt.%, such as from about 5 wt.% to about 20 wt.% based on the total weight of the solution, which can facilitate formation of a sufficient barrier between the first layer and the second layer to stop or prevent infiltration of the color from the first layer into the second layer, yet the glove can still have a suitable thickness at the reinforced portion for increased strength and chemical resistance.

[0103] In addition to a second powder free coagulant, the solution can include one or more other components. For instance, the solution can include a wax, a hydrogel, a silicone, a gel, an inorganic powder (e.g., carbonates, stearates, oxides, hydroxides, aluminates, etc.), an antimicrobial agent (e.g., silver (Ag++), copper (Cu++), polyhexamethylene biguanide (PHMB), etc.), an acrylic polymer, a peroxide crosslinking agent, an emollient (e.g., shea butter, petroleum, etc.), a hydrophilic agent, a hydrophobic agent, a pigment, a colorant, a dye, a polyolefin-based powder (e.g., a polyethylene powder or a polypropylene powder), a surfactant, a soap, an acidic agent, an alkali agent, or a combination thereof. These additional components can be present in the solution in an amount ranging from about 0.1 wt.% to about 30 wt.%, such as from about 0.5 wt.% to about 25 wt.%, such as from about 1 wt.% to about 20 wt.% based on the total weight of the solution.

[0104] Next, in step 308, the mold can be dried and reheated to approximately 70°C ±5°C, and dipped into a bath of a second formulation (e.g., the compounded nitrile rubber formulation of the second elastomeric material) one or more times (e.g., 1 , 2, 3, or 4 times) to form a second layer (e.g., the reinforcement layer) on a portion of the glove. In particular, in step 308, the mold is dipped to a level that does not cover the cuff portion of the mold. For instance, in step 308, the mold may be dipped to a level that covers the knuckle portion of fingers and thumb of the mold, i.e., dipped only for the finger region. The second layer may form a portion of the donning side of the glove.

[0105] The dip time of step 308 for the second formulation can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 15 second and 35 seconds is desirable. For instance, the dip time can be about 27 seconds. In some embodiments, the dip time for the second formulation can be longer than the dip time for the first formulation. The mold with the two layered gelled glove substrate applied thereon can then be soaked in water to remove all of the water-soluble material components. The mold with the gelled glove substrate applied thereon can then dried in an oven at a temperature ranging from about 80°C to about 100°C. Afterwards, in step 310, the glove is removed from the mold. The glove surfaces may thereafter be treated with chlorinated water to reduce the tackiness of the glove surfaces. Finally, the resulting gloves are dried, stripped from the former, and readied for packaging. Without intending to be limited by any particular theory, the present inventors have found that utilizing metallic salt at such increased amounts in step 306 can facilitate the formation of a glove having improved reinforcement in the reinforced portion of the glove.

[0106] Another method of forming the glove 101 is shown in FIG 6. As shown in FIG. 6, a four-dip process is contemplated that includes steps 602, 604, 606, 608, and 610. The process for forming an elastomeric glove entails providing a clean glove form or mold that can be preheated to approximately 55-60°C, and preferably about 58°C.

[0107] In step 602, the prepared mold is then is dipped into the second coagulant solution (e.g., an aqueous solution) comprising the second powder free coagulant that includes one or more metallic salts (e.g., nitrate, sulfate, or chloride salts of calcium, aluminum, or zinc, or a combination thereof). In particular, in step 602, the mold is dipped to a level that does not cover the cuff portion of the mold. For instance, in step 602, the mold may be dipped to a level that covers the knuckle portion of fingers and thumb of the mold, i.e., dipped only for the finger region. In one particular embodiment, the metallic salt may include calcium nitrate.

[0108] The dip time of step 602 for the second coagulant solution can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 10 seconds and 30 seconds is desirable. For instance, the dip time can be about 18 seconds.

[0109] The metallic salts can be present in the second coagulant solution in an amount ranging from about 3 wt.% to about 22 wt.%, such as from about 4 wt.% to about 21 wt.%, such as from about 5 wt.% to about 20 wt.% based on the total weight of the solution, which can facilitate formation of a sufficient barrier between the first layer and the second layer to stop or prevent infiltration of the color from the first layer into the second layer, yet the glove can still have a suitable thickness at the reinforced portion for increased strength and chemical resistance.

[0110] In addition to the second powder free coagulant, the solution can include one or more other components. For instance, the solution can include a wax, a hydrogel, a silicone, a gel, an inorganic powder (e.g., carbonates, stearates, oxides, hydroxides, aluminates, etc.), an antimicrobial agent (e.g., silver (Ag++), copper (Cu++), polyhexamethylene biguanide (PHMB), etc.), an acrylic polymer, a peroxide crosslinking agent, an emollient (e.g., shea butter, petroleum, etc.), a hydrophilic agent, a hydrophobic agent, a pigment, a colorant, a dye, a polyolefin-based powder (e.g., a polyethylene powder or a polypropylene powder), a surfactant, a soap, an acidic agent, an alkali agent, or a combination thereof. These additional components can be present in the solution in an amount ranging from about 0.1 wt.% to about 30 wt.%, such as from about 0.5 wt.% to about 25 wt.%, such as from about 1 wt.% to about 20 wt.% based on the total weight of the solution.

[0111] Next, in step 604, the mold can be dried and reheated to approximately 70°C ±5°C, and dipped into a bath of the second formulation (e.g., the compounded nitrile rubber formulation of the second elastomeric material) one or more times (e.g., 1 , 2, 3, or 4 times) to form the second layer (e.g., the reinforcement layer) on a portion of the mold. The second layer may form a portion of a grip side layer of the glove. In particular, in step 604, the mold is dipped to a level that does not cover the cuff portion of the mold. For instance, in step 604, the mold may be dipped to a level that covers the knuckle portion of fingers and thumb of the mold, i.e., dipped only for the finger region.

[0112] The dip time of step 604 for the second formulation can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 15 second and 35 seconds is desirable. For instance, the dip time can be about 27 seconds.

[0113] Next, in step 606, the mold is then dipped into the first coagulant solution (e.g., an aqueous solution) comprising the first powder free coagulant that includes one or more metallic salts (e.g., nitrate, sulfate, or chloride salts of calcium, aluminum, or zinc, or a combination thereof). In one particular embodiment, the metallic salt may include calcium nitrate.

[0114] The dip time of step 606 for the first coagulant solution can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 10 seconds and 30 seconds is desirable. For instance, the dip time can be about 16 seconds.

[0115] The metallic salts can be present in the first coagulant solution in an amount ranging from about 3 wt.% to about 15 wt.%, such as from about 6 wt.% to about 14 wt.%, such as from about 8 wt.% to about 12 wt.% based on the total weight of the solution.

[0116] In addition to the first powder free coagulant, the solution in step 606 can include one or more other components. For instance, the solution can include a wax, a hydrogel, a silicone, a gel, an inorganic powder (e.g., carbonates, stearates, oxides, hydroxides, aluminates, etc.), an antimicrobial agent (e.g., silver (Ag++), copper (Cu++), polyhexamethylene biguanide (PHMB), etc.), an acrylic polymer, a peroxide crosslinking agent, an emollient (e.g., shea butter, petroleum, etc.), a hydrophilic agent, a hydrophobic agent, a pigment, a colorant, a dye, a polyolefin- based powder (e.g., a polyethylene powder or a polypropylene powder), a surfactant, a soap, an acidic agent, an alkali agent, or a combination thereof. These additional components can be present in the solution in an amount ranging from about 0.1 wt.% to about 30 wt.%, such as from about 0.5 wt.% to about 25 wt.%, such as from about 1 wt.% to about 20 wt.% based on the total weight of the solution.

[0117] In step 608, the mold can be dried and reheated to approximately 70°C ±5°C, and dipped into a bath of the first formulation (e.g., the compounded nitrile rubber formulation of the first elastomeric material) to form the first layer (e.g., the donning side layer) of a gelled glove. The dip time for the first formulation can range from less than about 2 seconds to up to about 60 seconds. In one particular embodiment, a dip time between about 15 seconds and 30 seconds may be desirable. For instance, the dip time may be about 23 seconds. In some embodiments, the dip time for the first formulation can be longer than the dip time for the second formulation.

[0118] The mold with the two layered gelled glove substrate applied thereon can then be soaked in water to remove all of the water-soluble material components. The mold with the gelled glove substrate applied thereon can then dried in an oven at a temperature ranging from about 80°C to about 100°C. Afterwards, in step 610, the glove is removed from the mold. The glove surfaces may thereafter be treated with chlorinated water to reduce the tackiness of the glove surfaces. Finally, the resulting gloves are dried, stripped from the former, and readied for packaging. Without intending to be limited by any particular theory, the present inventors have found that utilizing metallic salt at such increased amounts in step 602 can facilitate the formation of a glove having improved reinforcement in the reinforced portion of the glove.

[0119] During the aforementioned dip processes of the methods 300 and 600, faster entry and exit speeds of the glove mold into the nitrile rubber formulation dipping solutions can provide a more even thickness profile to the glove, due at least in part to the reduced difference in residence time of the fingertip and cuff areas of the molds in the compounded formulations. The resulting increased thickness at the finger region of the glove may be attributed to the additional dip and additional nitrile rubber layer formed in the finger region as compared to the single elastomeric layer of the palm region and cuff region. The mold can be extracted from the dip bath at or near an initial vertical position and raised such that the finger tips are elevated to a horizontal or greater than horizontal position (e.g., tilted to an angle of about 20° to 45° above horizontal) for a brief period of time ranging from a few seconds to about 40 seconds. Quickly thereafter, the finger tip end of the mold can be lowered to a position or angle between horizontal and initial vertical, while rolling the mold along its longitudinal axis. The raising and lowering action can be repeated in a sinusoidal or wave-like motion. This process can enable the elastomeric material formulations (e.g., nitrile rubber formulations) to distribute more evenly over the mold or former and produce a substrate product that is thinner overall.

[0120] III. Examples

[0121] Example 1

[0122] In Example 1 , elastomeric gloves with a reinforced finger region were made using a first nitrile rubber formulation and a second nitrile rubber formulation via the 4-step coagulant dip-coating process of the method 600 described above. The first nitrile rubber formulation utilized to form the first layer of the glove included a total solids content (TSC) of about 32%, and included a black pigment and was dipped for a dwell time of about 23 seconds. The second nitrile rubber formulation utilized to form the second layer on the grip side of the glove included a total solids content (TSC) of about 15%, and included an orange pigment, and was dipped for a dwell time of about 27 seconds. The second coagulant solution dip (the first dip step, prior to the second nitrile formulation dip) included 20 wt.% calcium nitrate for a dip time of about 18 seconds. The first coagulant dip (the dip step after the second nitrile formulation dip of the reinforcement layer and before the first nitrile formulation dip) included 19 wt.% calcium nitrate for a dip time of about 16 seconds. The glove of Example 1 had a total weight of about 7.3 grams for a size Medium glove. The fingertip thickness of the glove of Example 1 was about 0.20 mm (8 mil), exhibiting a thickness of about 0.20 mm (8 mil) in the reinforced portion of the glove.

[0123] The glove of Example 1 was compared to an existing conventional multilayered nitrile glove formed by a 4-step coagulant dip-coating process in which the entire glove is formed from two layers, rather than only the finger region being formed from two layers as in Example 1 . The conventional glove was made using a first nitrile rubber formulation to form the grip side and a second nitrile rubber formulation to form the donning side. The grip side nitrile rubber formulation of the conventional glove included a total solids content (TSC) of about 19%, and included a black pigment, for a dip time of about 17 seconds. The donning side nitrile rubber formulation included a total solids content (TSC) of about 17%, and included an orange pigment, for a dip time of about 24 seconds. The first coagulant dip (the dip step prior to the first nitrile formulation dip) included 9 wt.% calcium nitrate for a dip time of about 16 seconds, while the second coagulant dip (the dip step after the first nitrile formulation dip and before the second nitrile rubber dip) included 9 wt.% calcium nitrate for a dip time of about 18 seconds. The conventional glove had a total weight of about 5.6 grams for a size Medium glove. The fingertip thickness of the conventional was about 0.15 mm (5.9 mil).

[0124] Thus, the present inventors found that the glove of Example 1 had about a 33% increase in fingertip thickness as compared to the conventional glove. Without intending to be bound by theory, the present inventors have found that the relative increase in concentration of the metallic salts in both the first coagulant solution and the second coagulant solution, as well as and the increase in total solids content (TSC) of the first nitrile rubber formulation, relative to the conventional glove, results in a glove having a suitable thinness in the palm, and cuff region to provide adequate tensile strength and chemical resistance without compromising ergonomics of the glove. Additionally, without intending to be bound by theory, the present inventors have found that the relative increase in concentration of the metallic salts in the second coagulant solution, relative to the conventional glove, prior to the partial dip in the second nitrile rubber formulation, results in a glove having a suitable thickness in the finger region to provide reinforcement in the finger region of the glove, improving tensile strength and chemical resistance in the most vulnerable portion of the glove.

[0125] The present invention has been described both in general and in detail by way of examples. These and other modifications and variations of the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole and in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims.

Claims

AMENDED CLAIMS received by the International Bureau on 11 May 2026 (11.05.2026)WHAT IS CLAIMED IS:

1. An elastomeric glove comprising: a first layer, wherein the first layer includes a first elastomeric material comprising nitrile rubber; and a second layer, wherein the second layer defines a reinforcement layer of the glove and includes a second elastomeric material comprising nitrile rubber, wherein the glove includes a reinforced portion including the first layer and the second layer, and a non-reinforced portion that is free of the second layer, wherein the glove includes a finger region, a palm region, and a cuff region, wherein the non-reinforced portion is spaced apart from the finger region.

2. The glove of claim 1 , wherein the finger region is comprised of the reinforced portion.

3. The glove of claim 1 , wherein the glove comprises a donning side and a grip side opposite the donning side, and the second layer is disposed on the grip side of the glove.

4. The glove of claim 1 , wherein the glove comprises a donning side and a grip side opposite the donning side, and the second layer is disposed on the donning side of the glove.

5. The glove of claim 1 , wherein a thickness of the finger region is greater than a thickness of the cuff region.

6. The glove of claim 5, wherein the finger region has a thickness in a range from about 0.1 mm to about 0.50 mm.

7. The glove of claim 5, wherein the cuff region has a thickness in a range from about 0.05 mm to about 0.40 mm.

8. The glove of claim 1 , wherein the first elastomeric material and the second elastomeric material are distinct.

9. The glove of claim 8, wherein the first elastomeric material and the second elastomeric material each comprise acrylonitrile, wherein the first elastomeric material and the second elastomeric material comprise unequal content of acrylonitrile by weight.

10. The glove of claim 9, wherein the second elastomeric material comprises a higher acrylonitrile content by weight than the first elastomeric material.11 . The glove of claim 10, wherein the acrylonitrile content of the second elastomeric material is in a range from about 30 wt. % to about 60 wt. %.

12. The glove of claim 1 , wherein the second material has a higher modulus of elasticity than the first material.

13. The glove of claim 1 , wherein the reinforced portion has a higher tensile strength than the non-reinforced portion.

14. The glove of claim 1 , wherein the reinforced portion has higher puncture resistance than the non-reinforced portion.

15. The glove of claim 1 , wherein a breach of the reinforced section exposes a distinct colored pigment of the first layer or the second layer to facilitate detection of the breach.

16. The glove of claim 1 , wherein the glove is reversible.

17. A method of making a multilayered elastomeric article, the method comprising: a) dipping a mold a first depth into a first solution comprising a first powder free coagulant, wherein the first powder free coagulant includes a first metallic salt, wherein the first metallic salt is present in an amount ranging from about 10 wt.% to about 30 wt.% based on the total wt.% of the first solution; b) dipping the mold the first depth into a first elastomeric formulation comprising a first elastomeric material to form a first layer, wherein the first elastomeric material comprises acrylonitrile; c) dipping the mold a second depth into a second solution comprising a second powder free coagulant, wherein the second powder free coagulant includes a second metallic salt, wherein the second metallic salt is present in an amount ranging from about 10 wt.% to about 30 wt.% based on the total wt.% of the second solution; d) dipping the mold a second depth into a second elastomeric formulation comprising a second elastomeric material to form a second layer, wherein the second elastomeric material comprises acrylonitrile; ande) curing the first elastomeric formulation and the second elastomeric formulation to form the reinforced elastomeric article, wherein the first depth is not equal to the second depth.

18. The method of claim 17, wherein the first depth is less than the second depth.

19. The method of claim 17, wherein the first depth is greater than the second depth.

20. The method of claim 17, wherein the first metallic salt in the first solution and the second metallic salt in the second solution include nitrate, sulfate, or chloride salts of calcium, aluminum, or zinc, or a combination thereof.21 . The method of claim 17, wherein the first solution, the second solution, or both further comprise a wax, a hydrogel, a silicone, a gel, an inorganic powder, an antimicrobial agent, an acrylic polymer, a peroxide crosslinking agent, an emollient, a hydrophilic agent, a hydrophobic agent, a pigment, a colorant, a dye, a polyolefin-based powder, a surfactant, a soap, an acidic agent, an alkali agent, or a combination thereof.

22. The method of claim 17, wherein the first elastomeric material and the second elastomeric material comprise unequal content of acrylonitrile by weight.

23. The glove of claim 22, wherein the second elastomeric material comprises a higher acrylonitrile content by weight than the first elastomeric material.

24. The method of claim 17, wherein the elastomeric article is a glove, further wherein either the first layer or the second layer forms a reinforcement layer on a partial portion of the glove.

25. The method of claim 24, wherein a finger region of the glove includes the reinforcement layer.

26. The method of claim 24, wherein a cuff region of the glove is free from the reinforcement layer.

27. The method of claim 24, wherein the reinforcement layer is present on a grip side of the glove.

28. The method of claim 24, wherein the reinforcement layer is present on a donning side of the glove.

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