FIELD OF THE INVENTION

The present invention relates to a giove with enhanced grip and in particular the method of producing thereof.

BACKGROUND OF THE INVENTION

Gloves made of natural rubber latex or synthetic rubber latex (from acrylonitrile butadiene rubber (NBR), poiyisoprene rubber, po!ychioroprene rubber, polyurethane rubber or combination thereof) are used as household glove, surgical glove, examination glove or industrial glove. An Important feature for gloves is to grasp items while wearing the gloves especially when dry, wet and/or oily objects are handled. Thus, gloves that provide slip-resistant and good gripping action when handling dry, wet and/or oily objects are desirable by the users.

Generally, the external surface of the glove can be textured in order to obtain superior gripping properties. Traditional approaches include the use of textured formers which are dipped into an aqueous latex emulsion resuiting in a textured glove surface corresponding to the contact surface of textured former. After the giove is inverted, the external glove surface which is the non-donning side becomes textured with a pattern molded on the former.

The existing prior art technology of making glove with good gripping performance depends on the pattern formed by different geometrical patterns such as diamond, honeycomb, fan, square, round, etc. Knowing that gripping performance can be affected by many factors including texture and surface condition of the objects and/or glove, load factors and manner of handling the objects, it is necessary to produce giove with more well-rounded gripping performance to provide coverage for most situations. US 7378043 B2 discloses synthetic or natural latex gloves and articles having enhanced gripping characteristics provided by virtue of a roughened, geometrically defined and surface integrally formed on the outer surface of the glove during its in-line manufacturing process.

WO 2017197429 discloses a method of forming a composite glove with a grip texture comprising: (a) providing a coagulant-coated support layer that is a fabric layer or a polymeric layer; (b) dipping the support layer in a foamed poiymer dispersion comprising about 0.5 % to about 2.0 % by weight of hygroscopic agent; (c) allowing a portion of the applied foamed polymer dispersion to coagulate with the coagulant that diffuses from the support layer to form a partially coagulated foam layer; (d) washing the partially coagulated foam layer to remove uncoagulated polymer to form a coagulated foam layer; and (e) vulcanizing the coagulated foam layer to form a vulcanized open foam layer laminated to the support to produce composite glove with a grip texture.

Typically, the existing methods have their own setback/drawback. The existing prior art technology may cause fatigue to the user due to more forces are required to grip onto the object of interest as the object may slip from the hand. Glove made from prior art technology with macropattern or with microtexture may face difficulty when handling slippery object leading to non-functional glove product to the user. Thus, there is a need to identify a suitable method to produce glove which provides sturdy grip to the user to hoid dry, wet and/or oily objects while wearing the glove.

Having said the above, it is obvious that existing approaches have their own disadvantages.

As such, there is a need to identify:

(1 ) a glove with enhanced grip in handling dry, wet and/or oily objects; and

(2) a method to produce a glove with enhanced grip in time and cost effective manner. SUMMARY OF THE INVENTION

The present invention relates to a giove with enhanced grip and the method of producing the glove. The glove consisting essentially of superimposed texture on the external surface of the glove which is the non-donning side wherein the superimposed texture is microtexture overiaid on macropattern. The glove comprises base polymer wherein the base polymer is any one selected from natural rubber (NR), acrylonitrile butadiene rubber (NBR), polyisoprene rubber, styrene butadiene rubber, polychloroprene rubber, polyurethane rubber and polyisobutylene rubber or a combination thereof. The glove has enhanced grip in handling dry, wet and/or oily objects. The glove is produced using a superimposed textured ceramic former.

The method of producing superimposed textured ceramic former comprises the steps of (i) casting ceramic greenware with engraved geometrical macropattern using drain casting method, (ii) embossing microtexture on the macropattern formed in step (i) using abrasive blasting by controlling nozzle pressure, bead size and bead type to produce overlapping microtexture on the macropattern layer on the ceramic greenware, (iii) air drying the ceramic greenware obtained in step (ii) overnight or drying in oven to produce modified ceramic greenware with superimposed texture, and (iv) firing the modified ceramic greenware with superimposed texture obtained in step (iii) to produce superimposed textured ceramic former. The superimposed textured ceramic former obtained in step (iv) is used to produce superimposed textured giove

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, wherein:

In the appended drawings: FIGURE 1 is a diagram showing the view of the (a) conventional diamond texture and (b) present invention’s superimposed diamond texture.

FIGURE 2 is a diagram showing the view of the (a) conventional zigzag texture and (b) present invention’s superimposed zigzag texture.

FIGURE 3 is a diagram showing the view of the superimposed diamond textured glove.

DETAILED DESCRIPTION OF THE INVENTION

Detailed description of preferred embodiments of the present invention is disclosed herein. It should be understood, however, that the embodiments are merely exemplary of the present invention, which may be embodied in various forms. Therefore, the details disclosed herein are not to be interpreted as limiting, but merely as the basis for the claims and for teaching one skilled in the art of the invention. The numerical data or ranges used In the specification are not to be construed as limiting. The following detailed description of the preferred embodiments will now be described in accordance with the attached drawings, either individually or in combination.

The present invention relates to a glove with enhanced grip and in particular to the method of producing thereof. Particularly the glove has superimposed finishing. The main objective of the present Invention is to produce glove with enhanced grip in handling dry, wet and/or oily objects using time and cost effective method.

Typically, in the present invention, ceramic formers with superimposed texture are used. In the context of the present invention, the term superimposed texture refers to microtexture overlaid on macropattern on the external surface of the glove which is the non-donning side.

The superimposed texture is produced on the contact surface of the ceramic formers by using abrasive blasting. The superimposed textured ceramic formers which are dipped into aqueous latex emulsion resulting in a superimposed textured glove surface at the contact surface of superimposed textured ceramic former. The superimposed textured glove has enhanced gripping properties.

The glove comprises base polymer wherein the base polymer is any one selected from natural rubber (NR), acrylonitrile butadiene rubber (NBR), polyisoprene rubber, styrene butadiene rubber, polychloroprene rubber, polyurethane rubber, polyisobutylene rubber or a combination thereof. in accordance with a preferred embodiment of the present invention, a method to produce superimposed textured ceramic former which is used to produce superimposed textured glove which in return provides an enhanced grip when handiing dry, wet and/or oily objects is disclosed.

The method of producing superimposed textured ceramic former comprises steps as described below:

i. casting ceramic greenware with engraved geometrical macropattern using drain casting method;

ii. embossing microtexture on the macropattern formed in step (i) using abrasive blasting by controlling nozzle pressure, bead size and bead type to produce overlapping microtexture on the macropattern layer on the ceramic greenware;

iii. air drying the ceramic greenware obtained in step (II) overnight or drying in oven to produce modified ceramic greenware with superimposed texture; iv. firing the modified ceramic greenware with superimposed texture obtained in step (iii) to produce superimposed textured ceramic former.

A superimposed textured glove is manufactured using the superimposed textured ceramic former. The method for producing the superimposed textured glove using the superimposed textured ceramic former is not disclosed as these follow conventional method known to person skilled in the glove manufacturing industry.

According to the invention, the ceramic greenware with engraved geometrical macropattern is casted using drain casting method wherein the slip density is in a range of 1.70 to 1.85 g/cm ³ , preferably 1.77 g/cm ³ and the slip flow is in a range of 18 to 24 seconds, preferably 21 seconds.

Thereafter, microtexture is embossed on the macropattern using abrasive blasting by controlling nozzle pressure to produce overlapping microtexture on the macropattern layer on the ceramic greenware. The pressure is in a range of 0.5 to 10 bar, preferably 1.5 bar. Bead type is ceramic, glass and/or steel, preferably glass. The bead size is in a range of 0.1 to 1.4 mm, preferably 0.6 mm.

The ceramic greenware is air dried overnight or dried in an oven at a temperature in a range of 50 to 75 ^° C, preferably 55 ^° C for a duration of 30 to 60 minutes, preferably 40 minutes to produce modified ceramic greenware. The modified ceramic greenware with superimposed texture is fired for a duration of 4 to 8 hours, preferably 6 hours at a temperature in a range of 1200 to 1400 C, preferably 1250 C to retain the superimposed texture and form a superimposed textured ceramic former. The superimposed textured ceramic former is used to produce glove with superimposed texture using conventional glove manufacturing process.

In the present invention, the process of abrasive blasting is used to create overlaid superimposed microtexture. Generally, abrasive blasting may blast away the macropattern on the ceramic greenware. Nevertheless, the present Invention is able to overcome this limitation because the abrasive blasting is conducted in a controlled manner. Thus, the present invention can successfully produce superimposed finishing on the ceramic former and glove.

Further, in the present invention, the modification via addition of overlaid microtexture helps to enhance the gripping properties by introducing enhanced glove surface interaction not only at macro- but also at micro-level. The key factor affecting the gripping properties of glove Is friction ievel at the contact area between glove surface and the contact surface of an article. Due to the presence of geometrical macropattern, macrostructures provide hysteresis grip and ploughing effect. Meanwhile, the adhesion grip Is contributed by the microstructures of the microtexture. By superimposing microtexiure over macropattern on glove, the resulting glove possesses strengths derived from each prospect. This is because the superimposed finishing provides additionai technicai advantage to ailow the grip in all-round direction as the finishing is not restricted by the distinct shape of conventional geometrical pattern.

Figure 1 discloses the view of the (a) conventional diamond texture and (b) present invention’s superimposed diamond texture. In reference to Figure 1 which discloses the exterior view of both the conventional diamond texture and present invention’s superimposed diamond texture, the present invention’s superimposed diamond texture is visually different due to the overiaid texture.

Figure 2 discioses the view of the (a) conventionai zigzag texture and (b) present invention’s superimposed zigzag texture. Figure 2 shows that the present invention is not limited to only macropattern such as diamond pattern but also other types of macropattern such as honeycomb, fish scale, zigzag, square, circle, wave, fan, star, etc.

Figure 3 discloses the view of the present invention’s superimposed diamond textured glove.

The glove derived from the present invention can be used as examination glove, high risk glove, household glove, industrial glove, surgical glove but not limited thereto. The glove derived from the present invention has thickness of at least 0.02 mm and weight of at least 2.0 g.

For the purpose of illustrating present invention in a non-limiting sense, hereinafter NBR examination glove and NR high risk glove are construed as examples of the gloves.

The NBR examination glove and NR high risk glove of the present invention are prepared by way of adopting a method commonly known in the glove manufacturing industry. The NBR examination glove comprises (a) acrylonitrile butadiene rubber (NBR), (b) pH adjuster, (c) stabilizer, (d) accelerator, (e) cross-linker and (f) anti-foaming agent. All the components are measured in parts per hundred rubber (phr) in preparing the NBR examination glove formulation. The NBR examination glove has thickness of at least 0.05mm and weight of at least 3.2g. The detailed NBR examination glove formulation is tabulated in Table 1 below.

Table 1 : Formulation for NBR examination glove.

The NR high risk glove comprises (a) NR latex, (b) pH adjuster, (c) stabilizer, (d) filler, (e) accelerator, (f) antioxidant and (g) cross-linker. All the components are measured in parts per hundred rubber (phr) in preparing the NR high risk glove formulation. The NR high risk glove has thickness of at least 0.14mm and weight of at least 8.0g. The detailed NR high risk glove formulation is tabulated in Table 2 below. Table 2: Formulation for NR high risk gloves.

The end product is glove with superimposed texture which is subjected for various analyses such as Coefficient of Friction (COF) test and tackiness test. COF test is conducted using universal tensile machine. Meanwhile, for the tackiness test, tackiness gauge is used for measuring grip properties in which the user is able to lift a load at highest possible angle. The higher the tackiness angle that is able to be lifted during the test, the better the grip. A comparative study was conducted between control gloves (gloves without superimposed texture) and test gloves (gloves with superimposed texture). During the comparative study all the formulations, parameters and conditions are kept constant and only the ceramic former served as variable.

The gripping performance using COF test for control gloves and test gloves of present invention for NBR examination gloves is shown in Table 3. Table 3: COF results for control gloves and test gloves of present invention for NBR examination gloves.

The gripping performance using COF test for control gloves and test gloves of present invention for NR high risk gloves Is shown in Table 4.

Table 4: COF results for control gloves and test gloves of present invention for NR high risk gloves.

Based on the results obtained in Table 3 and Table 4, it is dear that the test gloves of present invention for NBR examination gloves and NR high risk gloves show increased static and kinetic COF in dry, wet and oily conditions. Thus, it is concluded that gloves with superimposed texture showed higher static and kinetic COF in comparison with control gloves.

The tackiness performance of control gloves and test gloves of present Invention for NBR examination gloves in shown in Table 5.

Table 5: Grip performance of control gloves and test gloves of present invention for NBR examination gloves using tackiness test.

The tackiness performance of control gloves and test gloves of present Invention for NR high risk gloves is shown in Table 6.

Table 6: Grip performance of control gloves and test gloves of present invention for NR high risk gloves using tackiness test.

v indicates that the glove is able to meet the respective degree of tackiness X indicates that the glove is not able to meet the respective degree of tackiness

Based on the results obtained in Table 5 and Table 6, it is clear that the test gloves show increased level of tackiness in comparison with control gloves. Thus, it is concluded that gloves with superimposed texture showed higher degree of tackiness in comparison with control gloves.

The overall results clearly show that superimposed textured gloves have higher COF and higher degree of tackiness. The positive results clearly indicate enhanced gripping in the superimposed textured gloves. Further, the modification of the existing geometrical macropattern with additional microtexture is also cost effective as minimum resources are used for the production of superimposed textured gloves.

The latter is beneficial, whereby the application of the method of present invention is able to produce gloves with enhanced grip in handling dry, wet and/or oily objects without imparting negative impact on the physical properties of the gloves.

As a whole, the application of the method of present invention is able to overcome the conventional shortcomings since the method is able to produce gloves with superimposed finishing which have enhanced grip in handling dry, wet and/or oily objects in cost and time effective manner which can be used in a variety of applications such as but not limited to food handling, cosmetic, biomedical, semiconductor, electrical and/or healthcare.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms ''a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", “including”, and “having” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is aiso to be understood that additional or alternative steps may be employed. The use of the expression“at least” or“at least one” suggests the use of one or more elements, as the use may be in one of the embodiments to achieve one or more of the desired objects or results.