Medical gloves

Abstract

The present invention relates to medical gloves, in particular double donable gloves ("double gloves"). The present invention provides a process for making gloves, in particular polychloroprene gloves that are advantageously used in medical applications, in particular for surgery. The process according to the present invention dispenses with the need for accelerators and sulfur in the dispersion leading to the gloves. The process also results in gloves that exhibit reduced surface friction, which is achieved without the need for chlorination. Having reduced surface friction improves the donning properties of the gloves, either if donned as a single glove or in "double donning" systems. The present invention also relates to a set of such gloves or double gloves (comprising an under-glove and an over-glove). The present invention also relates to the use of an accelerator free polymer dispersion in the manufacture of gloves, in particular medical gloves.

Description

[0001] MEDICAL GLOVES

[0002] Field of the Invention

[0003] The present invention relates to medical gloves, in particular double donable gloves (“double gloves”). The present invention provides a process for making gloves, in particular polychloroprene gloves that are advantageously used in medical applications, in particular for surgery. The process according to the present invention dispenses with the need for accelerators and sulfur in the dispersion leading to the gloves. The process also results in gloves that exhibit reduced surface friction, which is achieved without the need for chlorination. Having reduced surface friction improves the donning properties of the gloves, either if donned as a single glove or in “double donning” systems. The present invention also relates to a set of such gloves or double gloves (comprising an under-glove and an over-glove). The present invention also relates to the use of an accelerator- and sulfur- free polymer dispersion in the manufacture of gloves, in particular medical gloves.

[0004] Background of the invention

[0005] Medical gloves are an important part of personal protective equipment (PPE) and are generally used to protect the wearer and / or the patient from the spread of micro-organisms or other substances, which may potentially cause infection or illness during medical procedures and examinations. Medical gloves are therefore also an important part of an infection-control strategy.

[0006] Medical gloves are meant to be disposable (“one time use”) and include examination gloves, surgical gloves, and gloves for handling chemotherapy agents (chemotherapy gloves). Medical gloves are typically regulated and need to meet certain performance criteria, such as leak resistance, certain physical properties (such as a comparatively high tensile strength), and biocompatibility. Surgical gloves typically have more precise sizing with a better precision and sensitivity and are made to a higher standard than examination gloves. Examination gloves are available as either sterile or non-sterile, while surgical gloves are generally sterile.

[0007] Medical gloves are made of different polymers, including latex (“natural rubber”), nitrile rubber (carboxylated polyacrylonitrile butadiene), polyvinyl chloride, or neoprene (polychloroprene).

[0008] Latex or “natural rubber” primarily consists of isoprene polymers. “Latex” is harvested from rubber trees growing under tropical conditions. Once the latex (or “rubber”) is vulcanized, the thermoplastic polymer becomes thermoset. Natural rubbers, while naturally sourced, are associated with several drawbacks that make these materials unsuitable for use in medical gloves. In particular, the presence of proteins in natural rubbers may lead to allergies in users, in particular a type I allergy (symptoms apparent within minutes after use).

[0009] Polyvinyl chloride polymer (PVC) based gloves are generally less stress resistant than nitrile or polychloroprene based gloves. Also, comparatively large amounts of plasticizers are needed, which is generally unwanted under environmental and user exposure aspects.

[0010] Double-donable (or simply “double”) medical gloves, i.e. gloves comprising an inner glove (“under-glove”) and an outer glove (“over-glove”) are of increasing importance, in particular for applications, in which breach of the integrity of the glove may lead to exposing a health care worker (HCW) or a patient to pathogens, blood or other bodily substances, which is generally unwanted. Such settings include but are not limited to surgical procedures. Studies show that the more difficult (or the longer) the surgical procedure, the more likely the use of double gloves by surgeons.

[0011] In order to facilitate “double donning”, the friction between the over-glove and the underglove should be reduced or minimized. According to the prior art, this is generally achieved by a chlorination process meant to reduce the surface friction particularly on the outer surface of the under-glove. PVC gloves are particularly easily chlorinated, but as mentioned above, PVC may not be the polymer of choice for high strength and puncture resistance medical gloves.

[0012] It is known that gloves made from a polychloroprene are not readily susceptible to chlorination (see, e.g., EP 1 511 610). Serious in-process difficulties are encountered in attempting to chlorinate polychloroprene gloves, mainly arising from the development of tackiness during processing. In order to improve their chlorination potential, polychloroprene gloves are often made from dispersions comprising a significant amount of another polymer that is more easily chlorinated. For example, EP 1 511 610 discloses to use a mixture of polychloroprene and carboxylated nitrile or SBR rubber to arrive at a surface that can be suitably chlorinated to reduce friction between inner and outer glove.

[0013] In another important aspect, polychloroprene gloves as known from the art are generally made based on dispersions comprising rubber accelerators, for example xanthate, dithiocarbamate, diphenylguanidine, N,N'-diphenyl thiourea etc. For example, US 9 550 906 discloses a vulcanization composition comprising sulfur and a xanthate accelerator in a process for making powder-free polychloroprene gloves. EP 1 511 610 also discloses the presence of accelerators in the dispersion leading to the glove.

[0014] The presence of accelerators may give rise to Type I (immediate hypersensitivity) and / or Type IV (delayed hypersensitivity) allergies to sensitized users.

[0015] On the other hand, while beneficial in terms of allergenicity, simply excluding accelerators from the dispersion leading to a glove may lead to insufficient tensile strength and force at break, failing to meet the stringent ASTM and EN requirements for medical gloves.

[0016] Summary of the Invention

[0017] In view of the drawbacks or limitations known from the art, it is therefore an object of the present invention to provide a process for making gloves and to provide gloves, in particular polychloroprene gloves, that minimize(s) or dispense(s) with the need for accelerators and sulfur in the dispersion leading to the glove. Also, the process should lead to and the glove should exhibit reduced surface friction. Said reduction of surface frictions should be achieved without the need for chlorination.

[0018] Thes objects, and others are achieved by the process as claimed, by the use of an accelerator- and sulfur-free dispersion as claimed and by the set of gloves I double glove as claimed.

[0019] Brief Description of the Figures

[0020] Fig. 1 : shows a schematic depiction of an exemplary process flow that is in accordance with the present invention. Fig 2 shows a schematic view of a cross-section through an exemplary glove made in accordance with the present invention: a thinner inner layer (i) comprising polyurethane is directly bonded to a thicker outer polychloroprene layer(o) that is coated with siloxane (not shown).

[0021] Figures 3 to 5 show scanning electron micrographs (SEMs) taken on three different samples of glove polymer layers of increasing surface roughness (more protrusions and indentations visible on the microscopic level); presence of surface irregularities is believed to be an indication of reduced contact area of the glove and thus reduced surface friction.

[0022] Fig. 3 : Control sample (Polychloroprene glove with no surface treatment / coating)

[0023] Fig. 4 : Glove with a polyurethane layer without previous acid prime treatment

[0024] Fig. 5 : Glove coated with a polyurethane coating and primed with 1.0 % HCI acid (in accordance with the invention)

[0025] Description of the Invention

[0026] The objects discussed above, and others, is / are solved by a process for the manufacture of a glove, suitable for medical use, in particular for surgical use, said process comprising at least the following steps:

[0027] (a) providing a composition comprising a solvent and polymer particles dispersed in said solvent, wherein said polymer particles are capable of cross-linking with a metal-oxide; wherein said composition further comprises a metal oxide as a cross-linking agent;

[0028] (b) dipping a glove former into the composition of (a), resulting in a layer deposited on said glove former; and subsequently retracting said glove former, with said layer deposited onto it, from the composition of step (a);

[0029] (c) at least partially drying the layer deposited on the glove former from step (b);

[0030] (d) optionally leaching chemical compounds out of the at least partially dried layer from step (c) in a washing step;

[0031] (e) dipping the glove former with the layer deposited onto it from step (c) or from step (d) into a priming solution which comprises at least one acid;

[0032] (f) optionally drying the layer deposited on the glove former from step (e); (g) providing - prior to or in parallel to or after any of steps (a) to (f) - a composition, comprising a solvent and a mixture of polymer particles, said mixture comprising polyurethane particles;

[0033] (h) dipping the glove former, with the layer deposited onto it, from step (e) or from step (f), into the composition of (g), thus creating a further layer on the already existing layer;

[0034] (i) curing the layers on the glove former from step (h) to result in a cured glove on the glove former;

[0035] (j) taking the cured glove of step (i) off the glove former and inverting the same;

[0036] (k) optionally washing the inverted glove from step (j) in an emulsion comprising a siloxane;

[0037] (l) treating the inverted glove from step (j) or from step (k) with a mixture of two different silicone polymers;

[0038] (m) drying the treated glove from step (I).

[0039] As disclosed above, the process of the invention comprises the following step (a):

[0040] (a) providing a composition comprising a solvent and polymer particles dispersed in said solvent, wherein said polymer particles are capable of cross-linking with a metal-oxide; wherein said composition further comprises a metal oxide as a cross-linking agent.

[0041] In preferred embodiments, the polymer particles of step (a) that are capable of crosslinking with a metal oxide comprise or are polychloroprene particles.

[0042] In preferred embodiments, the metal oxide of the composition of step (a) comprises or is zinc oxide.

[0043] Metal oxides in general and zinc oxide specifically is / are understood to be particularly suitable cross-linkers for polychloroprene since metal oxides, in particular zinc oxide react(s) with polychloroprene to form chlorides, which act as a catalyst for the isomerization of 1 ,2-units to 3-chloro-1 -butene. These units can then react with the neighboring 1 ,4-units to form carbonium ions, which can further react with other double bonds to form cross-links.

[0044] Other polymers that do not have this functionality, such as polyisoprene, do not undergo this reaction with a metal oxide. Polyisoprene may be crosslinked by other methods, such as sulfur vulcanization, peroxide curing, or radiation curing, which, however, is not desirable from a viewpoint of minimizing allergenics in the resulting glove.

[0045] Crosslinking polychloroprene with metal oxides such as zinc oxide leads to stable ionic crosslinks that results in gloves that have sufficient strength, in particular have sufficient tensile strength to meet the requirements for surgical gloves without the need to add any accelerator or vulcanization aid (such as sulfur) to the polymer mixture that leads to these gloves.

[0046] In preferred embodiments, the metal oxide, in particular zinc oxide is the only cross-linking agent present in the composition of step (a).

[0047] In preferred embodiments, the solvent in the composition of step (a) is or comprises water.

[0048] The process of the invention generally does not require the use of organic solvents, in particular does not require the use of volatile organic compounds (VOCs). The process is thus environmentally friendly and sustainable.

[0049] In preferred embodiments, the overall process leads to an under-glove and at least one pigment is added to the composition of step (a).

[0050] Over-gloves made in accordance with the process of the invention are generally not pigmented.

[0051] Pigmentation (for example blue pigmentation or green pigmentation) of the under-glove is only faintly visible when the under-glove is used together with an over-glove. However, if the integrity of the over-glove is compromised, for example due to a puncture or due to a cut, the pigmentation becomes fully visible in the area in which the integrity of the overglove is compromised, thus alerting the user to the breach.

[0052] In preferred embodiments, the composition of step (a) is an aqueous dispersion of polychloroprene particles suitable for dipping applications.

[0053] In preferred embodiments, the average particle size of the polychloroprene particles is from 0.5 pm to 5 pm. preferably from 0.8 pm to 2 pm. The average particle size is measured using conventional laser diffraction in accordance with ISO 13320:2009.

[0054] The amount of polymer particles (or other solid particles) in an aqueous dispersion can be suitably characterized by its “Total Solids Content (TSC), which is a commonly used parameter for rubber manufacturing.

[0055] The TSC is determined by measuring the weight of the dispersion (i.e. polymer particles in the solvent), then evaporating all solvent and measuring the weight of the remaining solid material. The TSC is then the ratio of the weight of the remaining solid material divided by the weight of the starting dispersion, (given in % w / w). In case the solvent is water, the complete evacuation of water is performed at a temperature from 100°C to 105°C.

[0056] In embodiments, the TSC of the dispersion of step (a) is from 20% to 50%, preferably from 30% to 45%.

[0057] In preferred embodiments, the composition of step (a) does not comprise more than trace amounts of chemical accelerators, in particular does not comprise more than trace amounts of any of the following, alone or in combination: ethylene thiourea (ETU), zinc diethyldithiocarbamate (ZDEC) or zinc dibutyldithiocarbamate (ZDBC), 1 ,3- Diphenylguanidine (DPG), 1 ,3-di-o-tolylguanidine (DOTG), Zinc 2-mercaptobenzothiazole (ZMBT), 1 ,3-Diphenyl-2 -thiourea (DPTU), or thiuram accelerators.

[0058] In preferred embodiments, none of the above-mentioned chemical accelerators is included in more than trace amounts in the composition of (a).

[0059] In accordance with the present disclosure, the term “not more than trace amounts" means not more than 1000 ppm, preferably not more than 500 ppm, preferably not more than 100 ppm.

[0060] As discussed in the introductory section above, the accelerators exemplified above, and other accelerators may lead to allergic reactions during use of the glove. It is thus desirable to minimize or avoid the use of any accelerator in the manufacture of a glove according to the present invention.

[0061] In further preferred embodiments and for essentially the same reasons as outlined in regard to the accelerators, the composition of step (a) does not comprise more than trace amounts of compounds comprising sulfur and / or does not comprise more than trace amounts of natural rubber.

[0062] In preferred embodiments, the composition of step (a) does not comprise sulfur and / or does not comprise natural rubber.

[0063] In preferred embodiments, the composition of step (a) also comprises at least one stabilizer, at least one further cross-linking agent (in addition to the metal oxide I zinc oxide) and at least one anti-tack agent. In a further aspect, the present invention also relates to the use of a composition of step

[0064] (a) of any of the embodiments described above, alone or in combination with each other, in the manufacture of an accelerator-free and sulfur-free glove.

[0065] As disclosed above, the process of the invention comprises the following step (b):

[0066] (b) dipping a glove former into the composition of step (a), resulting in a layer deposited on said glove former; and subsequently retracting said glove former, with said layer deposited onto it, from the composition of step (a).

[0067] In preferred embodiments, the glove former is coated with an anti-tack agent prior to dipping the same into the composition of step (a).

[0068] In further preferred embodiments, the anti-tack agent used in step (b) is selected from calcium nitrate, calcium carbonate or potassium stearate.

[0069] As disclosed above, the process of the invention comprises the following step (c):

[0070] (c) at least partially drying the layer deposited on the glove former from step (b).

[0071] In preferred embodiments, the at least partial drying of step (c) is conducted in a temperature range of from 70°C to 110 °C, preferably of from 80°C to 100°C.

[0072] Unless stated otherwise, all ranges disclosed herein include both end values (lower value and upper value).

[0073] In preferred embodiments, the at least partial drying of step (c) is conducted in a hot air oven.

[0074] While it cannot be ruled out that some partial curing of the layer as deposited on the glove former may occur in step (c) [or in any other drying step disclosed herein] - the primary objective of this step (c) [or of any other drying step disclosed herein] is to at least partially dry the coating, i.e. to remove at least some of the solvent (water) to result in a gel coating on the glove former.

[0075] In preferred embodiments, the thickness of the layer on the glove former after step (c) is from 200 pm to 700 pm, preferably from 300 pm to 400 pm.

[0076] As disclosed above, in preferred embodiments, the process may optionally comprise the following step (d):

[0077] (d) leaching chemical compounds out of the at least partially dried layer from step (c) in a washing step. As disclosed above, the process of the invention comprises the following step (e):

[0078] (e) dipping the glove former with the layer deposited onto it from step (c) or from step (d) into a priming solution which comprises at least one acid.

[0079] In preferred embodiments, the priming solution from step (e) comprises at least one acid selected from hydrochloric acid, nitric acid, sulfuric acid, acetic acid, phosphoric acid, or any combination thereof,

[0080] In particularly preferred embodiments, the at least one acid from step (e) is or comprises hydrochloric acid.

[0081] In preferred embodiments, the concentration of the acid in the aqueous priming solution is from 0.5 % w / w to 1 .5 % w / w, preferably from 0.8 % w / w to 1 .1 % w / w.

[0082] As discussed in more detail below, the acid priming step, together wi step (h) below, i.e. the application of a further, polyurethane-containing layer leads to a glove with a surface of reduced friction (after inversion - see below - this surface will be the “inner” surface of the final glove product). Such a glove can be suitably used, for example, as an over-glove in a double glove.

[0083] As disclosed above, in preferred embodiments, the process may optionally comprise the following step (f):

[0084] (f) drying the layer deposited on the glove former from step (e).

[0085] In preferred embodiments, the drying step (f) is conducted at a temperature range of from 80°C to 110 °C, preferably from 90°C to 100°C.

[0086] In preferred embodiments, drying step (f) is conducted in a hot air oven.

[0087] As disclosed above, the process of the invention comprises the following step (g):

[0088] (g) providing - prior to or in parallel to or after any of steps (a) to (f) - a composition, comprising a solvent and a mixture of polymer particles, said mixture comprising polyurethane particles.

[0089] In preferred embodiments, the total solids content of the polymer particles of the composition of (g) is from 2% to 10%, preferably from 3% to 8%, further preferably from 4% to 8%, wherein the % is given in % w / w respectively [see definition of the parameter “total solids content” provided above in the definition of step (a)]

[0090] This solids content was found to be particularly suitable for the dipping process used in the process of the present invention. In preferred embodiments the polymer mixture of composition of (g) also comprises polyacrylate and polychloroprene particles, i.e. the mixture comprises as polymer particles at least the following: polyurethane particles, polyacrylate particles and polychloroprene particles.

[0091] The mixture of the composition of step (g) also may comprise other polymer particles. The comprises a solvent. The composition may also comprise suitable adjuvants used in preparing compositions for dipping applications.

[0092] In preferred embodiments, in the polymer mixture of the composition of step (g), the amount of polyurethane is from 40% w / w to 60% w / w, the amount of polychloroprene is from 25% w / w to 45% w / w and the amount of polyacrylate is from 5% to 15% w / w, relative to the overall weight of the polymers in the composition, i.e. without the solvent (water). The ranges are understood to add up to 100%, i.e. if (only) 40% w / w of polyurethane is used, 45% w / w of polychloroprene must be present and 15% w / w of polyacrylate.

[0093] As disclosed above, the process of the invention comprises the following step (h):

[0094] (h) dipping the glove former, with the layer deposited onto it, from step (e) or from step (f), into the composition of (g), thus creating a further layer on the already existing layer.

[0095] As a result of step (h). a second polymer layer is coated onto the first polymer layer obtained in the previous sequence of steps.

[0096] In preferred embodiments, the thickness of the second layer resulting from step (h) is from 5 to 30 pm, preferably from 10 to 25 pm.

[0097] In preferred embodiments the second layer is thinner than the first layer.

[0098] As disclosed above, the process of the invention comprises the following step (i):

[0099] (i) curing the layers on the glove former from step (h) to result in a cured glove on the glove former;

[0100] In preferred embodiments, the curing step (i) is conducted at a temperature range of from 100°C to 150 °C, preferably from 120°C to 140°C.

[0101] In preferred embodiments, the curing step (i) is conducted for a time period of from 15 to 60 minutes, preferably from 20 to 40 minutes, further preferably from 25 to 30 minutes.

[0102] In further preferred embodiments, the curing is performed in a hot air oven.

[0103] As disclosed above, the process of the invention comprises the following step (j): (j) taking the cured glove of step (i) off the glove former and inverting the same.

[0104] As a result of this inversion, the second layer as coated onto the former in step (h), i.e. the polyurethane containing layer becomes the inner layer of the glove while the first layer as coated onto the former in step (b), i.e. the polychloroprene layer, becomes the outer layer of the glove in its final orientation.

[0105] This is schematically illustrated in Figure 2 with (i) being the inner layer and (o) being the outer layer.

[0106] As a result of the process, an inner PU-containing layer is directly bonded to an outer polychloroprene-containing layer.

[0107] The polyurethane coating of the inner layer of the glove reduces the friction between the glove and the hand of the user (in the case single gloving) or the friction between overglove and under-glove in the case of double gloving.

[0108] The outer surface of the inverted glove, i.e. the glove in its final configuration as intended for use is then subjected to the following surface treatment that does not involve a chlorination step as typically used in the art to reduce surface friction, but rather a treatment with different siloxanes / silicone polymers:

[0109] As disclosed above, in preferred embodiments, the process may optionally comprise the following washing step (k):

[0110] (k) optionally washing the inverted glove from step (j) in an emulsion comprising a siloxane

[0111] In preferred embodiments, the siloxane from step (k) is a linear polydimethylsiloxane.

[0112] In preferred embodiments, the siloxane from step (k) is present in a concentration range of from 0.05% w / w to 0.1 % w / w of the overall emulsion, wherein the solvent is or comprises water.

[0113] As disclosed above, the process of the invention comprises the following step (I):

[0114] (l) treating the inverted glove from step (j) or from step (k) with a mixture of two different silicone polymers;

[0115] In preferred embodiments, one of the two different silicone polymers in the mixture of (I) is a linear polydimethylsiloxane while the other of the two different silicone polymers is an amino-functional silicone polymer, optionally wherein the amino-functional silicone polymer is provided in a mixture comprising a surfactant. In a preferred embodiment of step (I), the gloves are tumbled together with the mixture of the two different siloxanes and a solvent, preferably water, in a tumbler.

[0116] As disclosed above, the process of the invention comprises the following step (m):

[0117] (m) drying the treated glove from step (I).

[0118] In preferred embodiments, the drying step (m) is conducted at a temperature range of from 70°C to 120 °C, preferably from 80°C to 100°C,

[0119] In preferred embodiments, the drying is carried out in a hot air oven.

[0120] In a further aspect of the present invention, the objects described above, and others, is / are also solved by a set comprising at least two gloves or by a double glove, respectively comprising:

[0121] • a first glove, which preferably is an under-glove;

[0122] • a second glove, which preferably is an over-glove, and which second glove is fitted or capable to be fitted over the first-glove; wherein the following applies to the first glove: a) the first glove comprises a metal oxide, preferably zinc oxide, but no sulfur; b) the first glove comprises two polymer layers, wherein the outer layer comprises polychloroprene; and wherein said outer layer comprises or is coated with at least one siloxane compound; c) further wherein said inner layer comprises at least a polyurethane; and the following applies to the second glove: a) the second glove comprises a metal oxide, preferably zinc oxide, but no sulfur b) the second glove comprises two polymer layers, wherein the outer layer comprises polychloroprene; c) further wherein said inner layer comprises at least a polyurethane.

[0123] In preferred embodiments, the first glove is an under-glove, and the second glove is an over-glove.

[0124] In preferred embodiments, the first glove is an under-glove that comprises at least one pigment. As already mentioned above, the pigmentation (for example blue or green) of the underglove is only faintly visible when the under-glove is used together with an over-glove. However, if the integrity of the over-glove is compromised, for example due to a puncture or due to a cut, the pigmentation becomes fully visible in the area in which the integrity of the over-glove is compromised, thus alerting the user to the breach.

[0125] In preferred embodiments, the make-up of the first glove and of the second glove is the same, in particular the chemical composition and sequence of layers is / are the same, with the one potential difference being the potential presence of a pigment in the first glove.

[0126] The process for making the first glove and the second glove is thus also the same (with the possible exception that the under-glove may be pigmented).

[0127] The following thus applies to both the first glove (preferably used as an under-glove) and the second glove (preferably used as an over-glove):

[0128] All structural features discussed above in regard to the process for making a glove, as well as all functional or process features that also manifest themselves in the resulting product, apply mutatis mutandis to the set of gloves or double glove according to this further aspect of the present invention.

[0129] In preferred embodiments, the outer layer of the glove comprises no polymer that can be chlorinated with active chlorine.

[0130] In accordance with the above embodiment, minimal chlorination that, however, does not noticeably affect the properties of the glove, in particular not its surface properties, is still included in the meaning of “cannot be chlorinated with active chlorine".

[0131] In preferred embodiments, the outer layer of the glove only comprises polychloroprene as the cross-linked polymer component. In other words: polychloroprene is the only polymer that structurally makes up said outer layer.

[0132] In accordance with the above embodiment, the presence of trace amounts of other polymers (see definition of the term “trace amounts” above) still results in a layer that only comprises polychloroprene as the cross-linked polymer component.

[0133] The presence of the surface active silicone polymers does not distract from the fact that , in this preferred embodiment, cross-linked polychloroprene is the only structural polymer making up the outer layer.

[0134] As explained in the background section above and as also apparent from the reference example below, polychloroprene containing gloves of the prior art are typically not just made from polychloroprene polymer particles (since those cannot be suitably surface- modified for better glove-donning properties) but also contain significant amounts of other polymers that can be chlorinated, for example carboxylated SBR (styrene butadiene rubber).

[0135] In accordance with the present invention, chlorination (i.e. the use of active chlorine) is avoided since the outer surface of the polychloroprene layer is modified with the siloxane treatment according to the present process.

[0136] In preferred embodiments, the outer layer of the glove comprises or is coated with at least two silicone polymers that are different from each other.

[0137] These silicone polymer / siloxanes of the outer layer can be present as a (partial) coating on the polychloroprene layer but may also be partly incorporated into the polychloroprene layer, depending on the specific of the “impregnation’Vcoating process.

[0138] In further preferred embodiments, one of the two different silicone polymers is a linear polydimethylsiloxane while the other of the two different silicone polymers is an aminofunctional silicone polymer, optionally further comprising a surfactant.

[0139] In preferred embodiments, an inner polyurethane-containing layer is directly bonded to an outer polychloroprene layer,

[0140] In preferred embodiments, said inner layer is thinner than said outer layer.

[0141] In preferred embodiments the thickness of the inner layer is less than 30%, preferably less than 20%, further preferably less than 10%, most preferred less than 5% of the thickness of the outer layer.

[0142] In preferred embodiments, the thickness of the outer layer is from 200 pm to 700 pm, preferably from 300 pm to 400 pm.

[0143] In preferred embodiments, the thickness of the inner layer is from 5 to 30 pm, preferably from 10 to 25 pm.

[0144] Since the inner layer does not have the primary function to provide structural strength, in particular tensile strength (this is the primary function of the polychloroprene outer layer) but rather to improve donning properties (reducing friction), this layer can be comparatively thin. This is advantageous since the dispersion comprising polyurethane used for applying the (ultimately) inner layer is comparatively more expensive than the polychloroprene particle dispersion used for applying the (ultimately) outer layer. In preferred embodiments, the tensile strength of the glove (i.e. the first glove and the second glove separately) after accelerated aging in accordance with Test Method D573 of ASTM D3577 19 (2023) is more than 12 MPa, preferably more than 15 MPa, further preferably more than 18 MPa. In accordance with the present invention, this tensile strength is achieved without the use of any accelerators, but rather by way of cross-linking the polychloroprene particles with a metal oxide.

[0145] Overall, the resulting gloves have significantly reduced allergenic potential, since they comprise no proteins resulting from naturally sourced polymers, comprise no chemical accelerators and also comprise no sulfur nor remnants of active chlorine.

[0146] Detailed Description of Embodiments of the Invention

[0147] In the technical field of gloves, the term “rubber” is used for all types of elastic polymers, which may be of “artificial” origin, i.e. synthesized from suitable monomers (“synthetic rubber”) or may be directly harvested from rubber trees (“natural rubber”).

[0148] While “latex” is an example of a naturally occurring rubber, the term “latex” is also used more generally to refer to a dispersion of polymers that can be further processed, in particular via curing, to elastomeric materials.

[0149] For example, the composition / dispersion of process step (a) may generally be referred to as a “latex dispersion”, even though it does not contain any natural latex.

[0150] In accordance with the present disclosure, a dispersion is understood to be a system, in which particles of one material (for example polymer particles) are dispersed in a continuous phase of another material (typically a solvent, for example water). The two phases may be in the same or different states of matter, for example solid particles in water.

[0151] An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or “unblendable”) owing to liquid-liquid phase separation.

[0152] By contrast, in a solution, only one (liquid) phase exists.

[0153] According to the IUPAC gold book [Source: PAC, 2007, 79, 1801 (Definitions of terms relating to the structure and processing of sols, gels, networks, and inorganic-organic hybrid materials (IUPAC Recommendations 2007)) on page 1806], and in accordance with the present disclosure, a gel is non-fluid colloidal network or polymer network that is expanded throughout its whole volume by a fluid.

[0154] As disclosed above, the process of the invention comprises the following step (a):

[0155] (a) providing a composition comprising a solvent and polymer particles dispersed in said solvent, wherein said polymer particles are capable of cross-linking with a metal-oxide; wherein said composition further comprises a metal oxide as a cross-linking agent.

[0156] In embodiments, the composition of step (a) comprises at least one stabilizer, at least one further cross-linking agent and at least one anti-tack agent. Examples of suitable stabilizers are: Disponil LDBS or Disponil OC 25. However, any other suitable stabilizer may be used, in particular potassium hydroxide, ammonia solution, Darvan l / IZAQ or Darvan SMO.

[0157] Examples of suitable anti-tack agents are Dispertack KStrlO (preferred) or Michemlube 180.

[0158] Exemplary antioxidants are Aquanox 56 (particularly preferred), Wingstay L or Ionol LC.

[0159] All names above in italics relate to tradenames of products that are commercially available at the time of filing of the present application. More details on specific materials are provide below in the Examples-Section.

[0160] A commonly used parameter in the field of elastomer / rubber formulations is the parameter “parts per hundred rubbed (phr), which refers to the mass fractions of individual components in a formulation for an elastomer / latex composition relative to the main polymer component (which is set at 100 parts).

[0161] In accordance with the present disclosure, any indication of “phr” is based on 100 (mass) parts of the base polymer or base polymers (in the case of polymer blends).

[0162] In the composition of step (a) said base polymers are the polymer particles in the dispersion, in particular polychloroprene polymer particles.

[0163] In preferred embodiments, the composition of step (a) comprises, per 100 parts of polymer particles (phr), the following components in the following respective amount:

[0164] • stabilizer(s) in a range of from 0.5 to 2 phr, preferably from 0.8 phr to 1.0 phr and / or

[0165] • cross-linking agent(s) in a range of from 5 phr to 15 phr, preferably from 8 phr to 12 phr; and / or

[0166] • antioxidant(s) in a range of from 0.5 phr to 2 phr, preferably from 0.8 phr to 1 ,2 phr and / or

[0167] • pigment(s) in a range of from 0.0 phr to 0.8 phr, preferably from 0.3 to 0.7 phr.

[0168] The following table shows exemplary ranges for additives that can be advantageously used in the composition of step (a), either individually or in combination:

[0169] “Chloroprene 750” is the trade name of a commercially available aqueous polychloroprene particle dispersion (previously commercialized by Showa Denko, at the time of filing commercialized by Resonac).

[0170] “Dehydrol" is the tradename for a family of commercially available emulsifiers / stabilizers (available, at the time of filing, from BASF).

[0171] “Wingstay L" is the tradename for a commercially available antioxidant (available, at the time of filing, from Synthomer).

[0172] “Colanyl Blue" is the tradename for a family of commercially available aqueous pigment preparations (available, at the time of filing, from Clariant).

[0173] As disclosed above, the process of the invention comprises the following step (g):

[0174] (g) providing - prior to or in parallel to or after any of steps (a) to (f) - a composition, comprising a solvent and a mixture of polymer particles comprising polyurethane particles;

[0175] In embodiments, the total solids content of the polymer particles of the composition of (g) is from 2% to 10%, preferably from 3% to 5%. The solids content is determined as disclosed above.

[0176] This solids content was found to be particularly suitable for the dipping step (h).

[0177] In preferred embodiments the polymer mixture of composition of (g) also comprises polyacrylate and polychloroprene. In preferred embodiments, in the polymer mixture of the composition of step (g), the amount of polyurethane is from 40% w / w to 60% w / w, the amount of polychloroprene is from 25% w / w to 45% w / w and the amount of polyacrylate is from 5% to 15% w / w, relative to the overall weight of the polymers in the composition, i.e. without the solvent (water). The ranges are understood to add up to 100%, i.e. if (only) 40% w / w of polyurethane is used, 45% w / w of polychloroprene must be present and 15% w / w of polyacrylate.

[0178] A suitable polymer (mixture) comprising polyurethane particles in dispersion together with polychloroprene and polyacrylate is commercially available under the trade name “Techem PIP 190” from the company Tech-Latex (“TLS”).

[0179] In preferred embodiments to the previous embodiment, said composition of step (g) comprises in addition to the polymer particles and per 100 phr of polymer mixture at least the following:

[0180] • 10 to 30 phr, preferably 15 to 25 phr of an amine, preferably of a partially methylated melamine and / or

[0181] • 20 to 40 phr, preferably 25 tp 35 phr of a dispersion of wax in water, preferably of oxidized high density polyethylene wax.

[0182] As an example, a suitable partially methylated melamine is available under the trade name “Cymel 373" from the company “Allnex".

[0183] Preferred partially methylated melamines combine water solubility with high reactivity, thus making these amines particularly suitable for fast-curing waterborne industrial formulations.

[0184] A suitable wax dispersion on the basis of oxidized HDPE is available under the trade name “Aquamat 263". from BYK Additives (Altana). This additive suitably works as an anti-tack agent.

[0185] As disclosed above, in preferred embodiments, the process may optionally comprise the following washing step (k):

[0186] (k) optionally washing the inverted glove from step (j) in an emulsion comprising a siloxane

[0187] In preferred embodiments, the siloxane from step (k) is a linear polydimethylsiloxane.

[0188] In preferred embodiments, the siloxane from step (k) is present in a concentration range of from 0.05% to 0.1% in the overall solution, wherein the solvent is or comprises water. A suitable siloxane is “Xiameter PMX-200" as commercially available from Dow Chemicals at the time of filing.

[0189] As disclosed above, the process of the invention comprises the following step (I):

[0190] (I) treating the inverted glove from step (j) or from step (k) with a mixture of two different silicone polymers.

[0191] In preferred embodiments, one of the two different silicone polymers is a linear polydimethylsiloxane while the other of the two different silicone polymers is an aminofunctional silicone polymer, optionally further comprising a surfactant.

[0192] A suitable linear polydimethylsiloxane can be taken from the Xiameter PMX-200 family. For example, at the time of filing, Xiameter PMX-200 (350 cSt) is commercially available from Dow Chemicals and generally used as a surface agent in cosmetics articles.

[0193] As a suitable amino-functional silicone polymer containing a surfactant, “Xiameter MEM 0939” is available from Dow Chemical. This composition is generally used in hair care applications. In a specific embodiment, the gloves are tumbled in a tumbler with 0.13 ml / glove of a linear polydimethylsiloxane emulsion (Xiameter PMX-200) applied together with a second siloxane emulsion, namely 0.33 - 0.44 ml / glove Xiameter MEM 0939, for about 5 minutes and dried at 90°C for 3 hours.

[0194] Examples:

[0195] The following Examples are provided to illustrate how to put the present invention into practice. These examples are provided for means of illustration only and are not meant to limit the claimed subject-matter.

[0196] Example 1 - Chlorinated polychloroprene glove containing accelerators (process according to the prior art - comparative example)

[0197] A thin-walled glove for surgical applications was made as follows. A glove shaped former was dipped into a solution of calcium nitrate (anti-tack agent) and then dried at 90°-110°C for 20-30 seconds.

[0198] The pre-treated former was then dipped into a dispersion comprising polychloroprene particles as commercialized (at the time of filing) by the company Resonac (“Chloroprene 750" previously also known as “Neoprene 750"), wherein this dispersion additionally contained 7.5% by weight of carboxylated SBR latex (i.e. polychloroprene and carboxylated SBR latex were present in a ratio of 92.5 : 7.5).

[0199] “Resonac’’ polychloroprene is an aqueous dispersion of polychloroprene polymer particles (commercialized with a total solids content around 50%) and is suitable for dipping applications.

[0200] The carboxylated SBR latex used was “Europrene 5583" available from Enichem, containing 40% (by weight) styrene; total solids content (TSC) = 40-46%.

[0201] This dispersion also contained Rhenocure, DPG (diphenyl guanidine) and Zinc BuD (zinc dibutyl dithiocarbamate) as accelerators, sulfur and zinc oxide as vulcanising agents / cross-linkers, Dehydol and Arylan as stabilizers, Wingstay L as antioxidant and Colanyl blue A2R as pigment.

[0202] The polymer-coated former (i.e., the former after having dipped the same into the dispersion described above) was dried at about 100°C for about 1 minute, followed by leaching in water at 55°-60°C for about 3 minutes, then dried in air for about 20 seconds.

[0203] The surface of the polymer coating on the former was then primed by dipping the same into a solution of 1 % hydrochloric acid, rinsed in water, then dried in a stream of hot air.

[0204] The polymer coated former was then dipped into a solution of Hydrocote A, a terpolymer consisting essentially of Hydroxethyl Methacrylate( HEMA), Methacrylic Acid (MAA) and 2-Ethylhexyl Methacrylate (EHA), together with p-Toluene sulfonic acid monohydride (p- TSA) as the catalyst and Cymel 370 (a partially methylated melamine crosslinker supplied in iso-butanol) as the amino crosslinker. The coating was beaded and cured at 125°-145°C for 25-30 minutes.

[0205] The cured / vulcanized glove was then stripped from the former (i.e. was inverted) and washed in water and dried.

[0206] The glove was then chlorinated according to the following procedure: a) the glove was washed in water and the water was drained off. b) the glove was tumbled in a solution containing 400-600ppm of available chlorine for about 20 minutes. c) sodium thiosulphate neutralizer was added and the glove was tumbled for a further 10 minutes. d) the glove was drained and washed.

[0207] The coefficient of friction and the subjective “double donning” experience of an over-glove and an under-glove made in accordance with this reference example / prior art can be found in Tables 1 and 2 below.

[0208] Example 2 - Polychloroprene glove containing no accelerators and not being chlorinated (in accordance with the invention)

[0209] A thin-walled glove for surgical application was made in accordance with the process described above in Example 1. However, in contrast to the process described in Example 1 , while the dispersion for coating did comprise polychloroprene Resonac 750, the dispersion did not contain any additional chlorinatable polymer (i.e. did not contain any carboxylated SBR latex) and also no accelerator and no sulfur.

[0210] This dispersion for coating, did contain stabilizer, zinc oxide, anti-oxidant, anti-tack agent (calcium stearate) and pigment as described above.

[0211] Specifically, the dispersion for coating had the following composition, given in units of “parts per hundred of rubber” (phr) as commonly used in the rubber industry (the main polymer is set at 100 parts).

[0212] The surface of the coated layer on the former as result of the dipping step above was then primed by dipping the coated former into a solution of 1.0 % hydrochloric acid, rinsed in water, then dried in a stream of hot air.

[0213] The coated and primed former was then dipped into a dispersion primarily comprising polyurethane polymer particles as a base material, together with polychloroprene and polyacrylate particles. Specifically, 100 parts of the polymer dispersion (Techem PIP 190) were formulated with 20 parts of a partially methylated melamine (Cymel 373) and 30 parts of a dispersion of an oxidized high density polyethylene wax (Aquamat 263).

[0214] At the time of filing, Techem PIP 190 is commercially available from Tech-Latex Scientific SDN. BHD. (Malaysia); the dispersion typically has totals solids content of 20% and is generally suitable for dipping applications leading to surgical gloves.

[0215] At the time of filing, Cymel 373 is commercially available from Allnex and generally used as a high performance cross-linker.

[0216] At the time of filing, Aquamat 263 is commercially available from BYK Additives (Altana) and generally used as an additive to improve surface properties of aqueous coatings.

[0217] As a result of this second dipping into a polymer dispersion, a second polymer layer is coated directly on the first layer, which is the polychloroprene layer described above.

[0218] The glove was “beaded”, i.e. rolled at the open end to increase stability, and then cured at a temperature in the range of from 125°-145°C for 25-30 minutes.

[0219] The glove was then stripped from the former, i.e. was inverted and washed in water. At that stage, i.e. after inversion, the outer surface is provided by the first layer that was coated onto the former (the polychloroprene layer) while the inner surface is provided by the second layer coated, i.e. the polyurethane-based coating (see Figure 2).

[0220] The inverted glove was then washed in a solution containing 0.075% of a linear polydimethylsiloxane (Xiameter PMX-200), and dried.

[0221] At the time of filing, Xiameter PMX-200 (350 cSt) is commercially available from Dow Chemicals and generally used as a surface agent in cosmetics articles.

[0222] No chlorination step was implemented for the glove, but the glove was instead treated according to the following procedure in order to further reduce surface friction. a) the glove was washed in water and the water was drained off. b) the glove was tumbled in a tumbler with 0.13 ml / glove of a linear polydimethylsiloxane emulsion (Xiameter PMX-200) applied together with a second silicone polymer emulsion, namely 0.33 - 0.44 ml / glove Xiameter MEM 0939, for about 5 minutes and dried at 90°C for 3 hours.

[0223] Xiameter MEM 0939 is also available from Dow Chemical and is a 35% cationic emulsion of an amino-functional silicone polymer containing a surfactant, which is generally used in hair care applications.

[0224] Results:

[0225] The improved donning properties of the gloves in accordance with the present invention and made in accordance with the process of the present invention were determined by two separate tests:

[0226] • a subjective glove double donning test, (see detailed description of this test in Annex A) using the following rating: measurement of the coefficient of friction (“COF”) using a commercially available friction measurement system (“Labthin ’) (see detailed description in Annex B) The glove of the present example in accordance with the invention resulted in a double donning test rating of 1-2, i.e. double donning is easily possible.

[0227] The process's efficacy in reducing surface friction was also assessed through the quantification of surface friction of the inner and outer surface of the gloves using the commercially available Labthink MXD-02 Coefficient of Friction Tester.

[0228] The coefficient of friction (COF) is a measure of the amount of resistance between two surfaces as they slide against each other. The coefficient quantifies how much force is required to keep one surface sliding over the other. In the context of double gloving, the coefficient of friction is relevant when considering the interaction between the inner surface of the over-glove and the outer surface of the under-glove.

[0229] The coefficient of friction provides insight into how much resistance builds up between the two surfaces of gloves in contact, i.e., the coefficient of friction is a measure how easily under-glove and over-glove can move relative to each other during double donning.

[0230] As mentioned above, the method of measuring the coefficient of friction (“COF”) of reference gloves and gloves in accordance of the invention (see Tables 1 and 2) using a commercially available “Labthink’ friction tester is described in detail in Annex B at the end of the description. The results are as follows.

[0231] Table 1: Coefficient of Friction (COF) of the inner surface of an over-glove against a reference plastic sheet Table 2: Coefficient of Friction (COF) of the inner surface of an over-glove vis-a-vis the outer surface of an under-glove

[0232] In addition to the friction measurements described above, microstructural analysis of the effect of polymer coating with polyurethane containing Techem PIP 190 as coated onto the inner surface of the polychloroprene glove was performed, using a Zeiss EVO 18, Scanning Electronic Microscope. The results are shown in Figures 3 - 5.

[0233] Without wishing to be bound by theory, it is believed that the degree of micro structurization as visible in the micrograph is an indicator of how easily two surfaces of this kind slide against each other on a macroscopic level. If the surface is or appears smooth and has few indentations and protrusions, the contact area between this surface and a second similar one will be high, which means that the surfaces will not slide easily against each other since a large contact area means a large area for interaction and thus high friction.

[0234] On the other hand, if a surface is strongly structured and has many indentations and protrusions, the contact area will be significantly lower and thus also the potential for friction is reduced.

[0235] Figure 3 shows an SEM Micrograph of the surface of polychloroprene only (i.e. no application of further PU-based layer as described above to be in accordance with the invention). The surface appears comparatively smooth and unstructured in the micrograph. By contrast, as shown in Figure 4, if the polychloroprene is coated with a thin polyurethane- based layer, significant structurization of the surface can be observed.

[0236] Surface structurization increases even more and the potential contact area is further minimized when the polychloroprene layer is primed with HCI prior to application of the second (thin) PU-based layer (see Figure 5). In sum, the microstructural analysis further corroborates the fact that the process of the invention leads to gloves that are in accordance with the invention and that show decreased friction between over-glove and under-glove thus leading to improved donability.

[0237] Process Flow:

[0238] For sake of illustration, the process discussed in Example 2 may also be described by the following process flow scheme (see also Figure 1):

[0239] (a) Formulating dispersion of polychloroprene polymer particles; dispersion does not contain chlorinatable polymer, nor accelerators nor sulfur; dispersion does contain stabilizer, zinc oxide, antioxidant and anti-tack agent; minimum maturation time: 2.5 days; total solid content of approx. 38%.

[0240] (b) Glove shaped former is dipped into the dispersion of (a).

[0241] (c) Coated former is dried at about 100°C for about 1 minute; cuff is beaded (“rolled” at the open end) to increase strength.

[0242] (d) Polymer coating on the former is leached in water at 55°-60°C for about 3 minutes; then dried in air for about 20 seconds.

[0243] (e, f) Surface of the polymer coating on the former is primed by dipping the same into a solution of 1 % hydrochloric acid, rinsed in water, then dried in a stream of hot air.

[0244] (g, h) Former with first coating that has been primed is then dipped into a dispersion of polymer particles comprising polyurethane as a base material and additionally comprising polychloroprene and polyacrylate particles.

[0245] (i) Coated former with two polymer layers is cured at 125°-145°C for 25-30 minutes.

[0246] (j) Glove is stripped from the former (“inverted”) and washed in water;

[0247] (k) Glove is washed in a solution containing 0.075% siloxane and dried.

[0248] (l) Glove is tumbled with 0.13 ml / glove 8% linear polydimethylsiloxane emulsion and 0.33 to 0.44 ml / glove 35% amine functional silicone polymer emulsion for about 5 minutes and dried at 90°C for 3 hours.

[0249] Annex A

[0250] The subjective glove donning test was conducted in the following manner:

[0251] The tester puts the under-glove on the correct hand. The tester then takes an over-glove and folds back the gauntlet until the bead of the over-glove reaches the bottom of the thumb crotch. The tester then holds the front of the open end of the over-glove using the thumb and forefinger of the other hand and insert the already gloved hand (under-glove) into the over-glove. The tester then pulls the open end of the glove with the thumb and forefinger and simultaneously pushes the gloved hand forward to slip on the over-glove.

[0252] The subjective double donning test is assessed using the following rating:

[0253] Annex B:

[0254] The measurement of the coefficient of friction (“COF”) of reference gloves and gloves in accordance with the invention (see Tables 1 and 2) using a friction tester “MXD-02" (at the time of filing commercially available from “Labthin ’) is carried out as follows: a) The glove samples are conditioned for at least 40 hours. b) Cut off Thumb and fingers of glove. The glove sample is cut open and cut so size. c) A reference plastic sheet (polypropylene) or the glove to be measured is cut to the dimension of 250 mm x 130 mm (length X width). d) The plastic sheet or the glove is attached to the plane to provide one of the surfaces against which friction is measured. e) A 95 mm x 95 mm plastic sheet (polypropylene) or the (second) glove as test specimen is prepared. This plastic sheet I glove is attached to the sled of the friction tester (see panel 2-b, Figure 1). f) Testing is performed in accordance with the protocol of the friction tester “MXD-02" g) 5 pieces of control specimen (polypropylene sheet are tested before carrying out all testing with the materials shown in Table 1 and 2 within one day. i) Calculation

[0255] Static Coefficient of Friction, ps = As / B ; wherein: As = initial motion scale reading, g, and B = sled weight, g.

[0256] Dynamic Coefficient of Friction, pd = Ad / B ; wherein: Ad = average scale reading obtained during uniform sliding of the film surfaces, g, and B = sled weight, g.

[0257] Note: ps and pd are automatically provided by the software of the friction tester “MXD-02"

Claims

Claims1. Process for the manufacture of a glove, suitable for medical use, in particular for surgical use, said process comprising at least the following steps:(a) providing a composition comprising a solvent and polymer particles dispersed in said solvent, wherein said polymer particles are capable of cross-linking with a metal-oxide; wherein said composition further comprises a metal oxide as a cross-linking agent;(b) dipping a glove former into the composition of step (a), resulting in a layer deposited on said glove former; and subsequently retracting said glove former, with said layer deposited onto it, from the composition of step (a);(c) at least partially drying the layer deposited on the glove former from step (b);(d) optionally leaching chemical compounds out of the at least partially dried layer from step (c) in a washing step;(e) dipping the glove former with the layer deposited onto it from step (c) or from step (d) into a priming solution which comprises at least one acid;(f) optionally drying the layer from step (e);(g) providing - prior to or in parallel to or after any of steps (a) to (f) - a composition, comprising a solvent and a mixture of polymer particles, said mixture comprising polyurethane particles;(h) dipping the glove former, with the layer deposited onto it, from step (e) or from step (f), into the composition of (g), thus creating a further layer on the already existing layer;(i) curing the layers on the glove former from step (h) to result in a cured glove on the glove former;(j) taking the cured glove of step (i) off the glove former and inverting the same;(k) optionally washing the inverted glove from step (j) in an emulsion comprising a siloxane;(l) treating the inverted glove from step (j) or from step (k) with a mixture of two different silicone polymers;(m) drying the treated glove from step (I).

2. Process according to claim 1 , wherein the polymer particles that are capable of cross-linking with a metal oxide comprise polychloroprene particles, preferably wherein the polymer particles that are capable of cross-linking with a metal oxide are polychloroprene particles3. Process according to claim 1 or claim 2, wherein the metal oxide of the composition of step (a) comprises or is zinc oxide, preferably wherein said zinc oxide is the only cross-linking agent in the composition of step (a).

4. Process according to any of the preceding claims, wherein the solvent of the composition of step (a) comprises or is water.

5. Process according to any of the preceding claims, wherein the solvent of the composition of step (a) does not comprise an organic solvent.

6. Process according to any of the preceding claims, wherein the composition of step (a) is an aqueous dispersion of polychloroprene particles, suitable for dipping applications.

7. Process according to any of claims 2 - 6, wherein the average particle size of the polychloroprene particles, in the composition of step (a) is from 0.5 pm to 5 pm. preferably from 0.8 pm to 2 pm.

8. Process according to any of the preceding claims, wherein the total solids content of the composition of step (a) is from 20% to 50%, preferably from 30% to 45%.

9. Process according to any of the preceding claims, wherein at least one pigment is added to the composition of step (a), preferably wherein the resulting glove is an under-glove.

10. Process according to any of the preceding claims, wherein the composition of (a) comprise no chemical accelerators or does not comprise more than trace amounts of chemical accelerators.

11. Process according to claim 10, wherein the following is not included in the composition of step (a), or is included only in trace amounts: ethylene thiourea (ETU), zinc diethyldithiocarbamate (ZDEC) or zinc dibutyldithiocarbamate (ZDBC), 1 ,3-Diphenylguanidine (DPG), 1 ,3-di-o-tolylguanidine (DOTG), Zinc 2- mercaptobenzothiazole (ZMBT), 1 ,3-Diphenyl-2 -thiourea (DPTU), or thiuram accelerators.

12. Process according to any of the preceding claims, wherein the composition of step (a) does not comprise, or does not comprise more than trace amounts of, compounds comprising sulfur13. Process according to any of the preceding claims, wherein the composition of step (a) does not comprise, or does not comprise more than trace amounts of, natural rubber.

14. Use of the composition of step (a) of any of claims 1 - 13 in the manufacture of an accelerator-free and sulfur-free glove, or a glove that only comprises trace amounts of accelerator and sulfur.

15. Process according to any of the preceding claims, wherein in step (b), the glove former is coated with an anti-tack agent prior to dipping the same into the composition of step (a).

16. Process according to claim 15, wherein the anti-tack agent used in step (b) is selected from calcium nitrate, calcium carbonate or potassium stearate.

17. Process according to any of the preceding claims, wherein the at least partial drying of step (c) is conducted at a temperature range of from 70°C to 110 °C, preferably of from 80°C to 100°C.

18. Process according to any of the preceding claims, wherein the thickness of the layer on the glove former after step (c) is from 200 pm to 700 pm, preferably from 300 pm to 400 pm.

19. Process according to any of the preceding claims, wherein the priming solution from step (e) comprises at least one acid selected from hydrochloric acid, nitric acid, sulfuric acid, acetic acid, phosphoric acid, or any combination thereof, preferably wherein the priming solution is a HCI solution.

20. Process according to claim 19, wherein the concentration of the acid in the priming solution, in particular the concentration of HCI, is from 0.5 % w / w to 1.5 % w / w, preferably from 0.8 % w / w to 1 .1 % w / w.21 . Process according to any of the preceding claims, wherein the optional drying step(f) is conducted at a temperature range of from 80°C to 110 °C, preferably from90°C to 100°C.

22. Process according to any of the preceding claims, wherein the total solids content of the polymer particles of the composition of (g) is from 2% to 10%, preferably from 3% to 8% w / w, further preferably from 4% to 8%.

23. Process according to any of the preceding claims, wherein the composition of (g) also comprises an amine and a dispersion of wax in water.

24. Process according to any of the preceding claims, wherein the polymer mixture of composition of (g) also comprises polyacrylate and polychloroprene particles.

25. Process according to claim 24, wherein in the polymer mixture of the composition of step (g), the amount of polyurethane is from 40% w / w to 60% w / w, the amount of polychloroprene is from 25% w / w to 45% w / w and the amount of polyacrylate is from 5% to 15% w / w, relative to the overall weight of the polymers in the composition, without the solvent.

26. Process according to any of the preceding claims, wherein the curing step (i) is conducted at a temperature range of from 100°C to 150 °C, preferably of from 120°C to 140°C.

27. Process according to claim 26, wherein the curing step (i) is conducted for a time period of from 15 to 60 minutes, preferably from 20 to 40 minutes, further preferably from 25 to 30 minutes.

28. Process according to any of the preceding claims, wherein the siloxane from step (k) is a linear polydimethylsiloxane.

29. Process according to any of the preceding claims, wherein one of the two different silicone polymers in the mixture of (I) is a linear polydimethylsiloxane while the other of the two different silicone polymers is an amino-functional silicone polymer.

30. Process according to claim 29, wherein the amino-functional silicone polymer is provided in a mixture with a surfactant.

31. Process according to any of the preceding claims, wherein the drying step (m) is conducted at a temperature range of from 70°C to 120 °C, preferably from 80°C to 100°C.

32. A set comprising at least two gloves, or a double glove, respectively comprising:• a first glove, which preferably is an under-glove;• a second glove, which preferably is an over-glove, and which second glove is fitted or capable to be fitted over the first-glove; wherein the following applies to the first glove:(a) the first glove comprises a metal oxide, preferably zinc oxide, but no sulfur;(b) the first glove comprises two polymer layers, wherein the outer layer comprises polychloroprene; and wherein said outer layer comprises or is coated with at least one siloxane compound;(c) further wherein said inner layer comprises at least a polyurethane; and the following applies to the second glove:(a) the second glove comprises a metal oxide, preferably zinc oxide, but no sulfur(b) the second glove comprises two polymer layers, wherein the outer layer comprises polychloroprene;(c) further wherein said inner layer comprises at least a polyurethane.

33. Set of gloves or double glove of claim 32, wherein the first glove comprises at least one pigment.

34. Set of gloves or double glove of claim 32, wherein the make-up of the first glove and the second glove is the same, in particular the chemical composition and sequence of layers is / are the same, with the one potential difference being the potential presence of a pigment in the first glove.

35. Set of gloves or double glove of any one of claims 32 - 34 , wherein the outer layer of the first glove and of the second glove, respectively, comprises no polymer that can be chlorinated with active chlorine.

36. Set of gloves or double glove of any one of claims 32 - 35, wherein the outer layer of the first glove and of the second glove, respectively, only comprises polychloroprene as the polymer component.

37. Set of gloves or double glove of any one of claims 32 - 36, wherein the outer layer of the first glove and of the second glove, respectively, comprises two different silicone polymers, preferably two different siloxanes.

38. Set of gloves or double glove of claim 37, wherein one of the two different silicone polymers is a linear polydimethylsiloxane while the other of the two different silicone polymers is an amino-functional silicone polymer.

39. Set of gloves or double glove of any one of claims 32 - 38, wherein both the first glove and the second glove comprise an inner polyurethane-containing layer that is directly bonded to an outer polychloroprene-containing layer.

40. Set of gloves or double glove of claim 39, wherein the inner polyurethane-containing layer also comprises polyacrylate and polychloroprene.41 . Set of gloves or double glove of any one of claims 32 - 40, wherein said inner layer is thinner than said outer layer.

42. Set of gloves or double glove of claim 41 , wherein the thickness of said inner layer is less than 30%, preferably less than 20%, further preferably less than 10%, most preferred less than 5% of the thickness of the outer layer.43 Set of gloves or double glove of any one of claims 32 - 42, wherein the thickness of the outer layer is from 200 pm to 700 pm, preferably from 300 pm to 400 pm.

44. Set of gloves or double glove of any one of claims 32 - 43, wherein the thickness of the inner layer is from 5 to 30 pm, preferably from 10 to 25 pm.

45. Set of gloves or double glove of any one of claims 32 - 44, wherein the tensile strength of each glove, i.e. the first glove and the second glove respectively, after accelerated aging in accordance with Test Method D573 of ASTM D3577 19 (2023) is more than 14 MPa, preferably more than 16 MPa, further preferably more than 18 MPa.

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