WO2015199965A1

WO2015199965A1 - Polyvinylidene fluoride chemical resistant glove and thermal/coaguable dipping process

Info

Publication number: WO2015199965A1
Application number: PCT/US2015/034779
Authority: WO
Inventors: Michael David Johnson; Charles Terrence Brown
Original assignee: Honeywell International Inc.
Priority date: 2014-06-24
Filing date: 2015-06-09
Publication date: 2015-12-30

Abstract

Embodiments relate generally to methods for forming a chemically resistant glove. The chemical resistant glove may comprise a polyvinylidene fluoride (PVDF) and acrylic material, as well as a coagulant and a plasticizer. The method may comprise preheating a coagulant material to approximately 110 degrees Fahrenheit (˚F); preheating a glove form to approximately 115˚F; dipping the glove form into the coagulant material; drying the coagulant on the glove form; dipping the glove form having the coagulant into a PVDF and acrylic dispersion material to form at least a film on the glove form; leaching the glove form having the film disposed thereon; drying the glove form having the film disposed thereon, wherein the dried film forms a glove material; and removing the glove material from the glove form.

Description

POLYVINYLIDENE FLUORIDE CHEMICAL RESISTANT GLOVE AND

THERMAL/COAGUABLE DIPPING PROCESS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application Serial No. 62/016,438, filed on June 24, 2014, which is hereby incorporated by reference in its entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.

REFERENCE TO A MICROFICHE APPENDIX

[0003] Not applicable.

BACKGROUND

[0004] Seamless, three-dimensional gloves may be formed using a glove form and dipping the glove into a liquidized material that may dry to form the glove material. Such gloves may be used to protect a user’s hands from chemicals, dust, grease, or other harmful substances. These gloves may be formed in varies sizes to accommodate the user.

SUMMARY

[0005] Aspects of the disclosure may include embodiments of a method for forming a chemical resistant glove comprising: preheating a coagulant material to approximately 110 degrees Fahrenheit (°F); preheating a glove form to approximately 115°F; dipping the glove form into the coagulant material; drying the coagulant on the glove form; dipping the glove form having the coagulant into a polyvinylidene fluoride (PVDF) and acrylic dispersion material to form at least a film on the glove form; leaching the glove form having the film disposed thereon; drying the glove form having the film disposed thereon, wherein the dried film forms a glove material; and removing the glove material from the glove form.

[0006] In some embodiments, the coagulant may comprise specific gravity of approximately 1.30. In some embodiments, dipping the glove form into coagulant may comprise dipping the glove form into coagulant at a rate of 0.5 inches per second (”/sec); removing the glove from the coagulant at a rate of 0.5”/sec; repeating the dipping and removing for a predetermined number of dips to form the desired thickness of coagulant on the glove form; tending the glove form up for 10 seconds; and tending the glove form down for 10 seconds. In some embodiments, drying the coagulant on the glove form may comprise drying the coagulant on the glove form for approximately 30 minutes at approximately 140°F. In some embodiments, dipping the glove form having the coagulant into the PVDF and acrylic dispersion material may comprise dipping the glove form into PVDF and acrylic dispersion material at a rate of 0.5 inches per second (”/sec); dwelling the glove form in the PVDF and acrylic dispersion material for approximately 1 minute; removing the glove from the PVDF and acrylic dispersion material at a rate of 0.5”/sec; and repeating the dipping, dwelling, and removing for a predetermined number of dips to form the desired thickness of film on the glove form. In some embodiments, drying the glove form having the film disposed thereon may comprise drying the glove form having the film disposed thereon for approximately 2 hours at approximately 140°F. In some embodiments, the method may further comprise adding fabric layer to the glove material. In some embodiments, the method may further comprise cooling the glove form having the film disposed thereon to room temperature before removing the glove material from the glove form.

[0007] Additional aspects of the disclosure may include embodiments of a method for forming a chemical resistant glove comprising dipping a glove form in a coagulant; drying the coagulant on the glove form; dipping the glove form having the coagulant in an aqueous dispersion comprising PVDF polymer to form a portion of the glove material on the glove form; drying the glove form having the dispersion disposed thereon; and removing the glove material from the glove form.

[0008] In some embodiments, the coagulant may comprise calcium nitrate. In some embodiments, the glove form may be a porcelain glove form. In some embodiments, the aqueous dispersion may comprise a vinyl resin. In some embodiments, the aqueous dispersion may comprise a plasticizer. In some embodiments, the plasticizer may comprise sebacate. In some embodiments, the method may further comprise disposing a fabric layer over the glove form prior to dipping the glove form in the coagulant.

[0009] Other aspects of the disclosure may include embodiments of a chemically resistant glove comprising a three-dimensional glove shape formed from a glove material, wherein the glove material comprises a PVDF and acrylic polymer, a plasticizer, and coagulant.

[0010] In some embodiments, the plasticizer may comprise sebacate. In some embodiments, the glove material may have a thickness of between about 10 mils and about 30 mils. In some embodiments, the glove may further comprise a fabric layer, wherein the glove material is disposed on at least a portion of the outer surface of the fabric layer. In some embodiments, the coagulant comprises calcium nitrate.

[0011] These and other features will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] For a more complete understanding of the present disclosure, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts.

[0013] FIG. 1 illustrates a method for forming a chemically resistant glove.

DETAILED DESCRIPTION

[0014] It should be understood at the outset that although illustrative implementations of one or more embodiments are illustrated below, the disclosed systems and methods may be implemented using any number of techniques, whether currently known or not yet in existence.

[0015] The disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, but may be modified within the scope of the appended claims along with their full scope of equivalents.

[0016] The following brief definition of terms shall apply throughout the application: [0017] The term“comprising” means including but not limited to, and should be interpreted in the manner it is typically used in the patent context;

[0018] The phrases“in one embodiment,”“according to one embodiment,” and the like generally mean that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present invention, and may be included in more than one embodiment of the present invention (importantly, such phrases do not necessarily refer to the same embodiment);

[0019] If the specification describes something as“exemplary” or an“example,” it should be understood that refers to a non-exclusive example;

[0020] The terms“about” or approximately” or the like, when used with a number, may mean that specific number, or alternatively, a range in proximity to the specific number, as understood by persons of skill in the art field; and

[0021] If the specification states a component or feature“may,”“can,”“could,”“should,” “would,”“preferably,”“possibly,”“typically,”“optionally,”“for example,”“often,” or“might” (or other such language) be included or have a characteristic, that particular component or feature is not required to be included or to have the characteristic. Such component or feature may be optionally included in some embodiments, or it may be excluded.

[0022] It should be understood at the outset that although illustrative implementations of one or more embodiments are illustrated below, the disclosed systems and methods may be implemented using any number of techniques, whether currently known or not yet in existence. The disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, but may be modified within the scope of the appended claims along with their full scope of equivalents.

[0023] Embodiments relate generally to improved (lower cost) chemical resistant gloves for use to protect against a wide range of chemicals. The gloves may also provide improved hand comfort during use. Additionally, the durability or toughness of the gloves (dependent on the polymer used to form the gloves) may be important for safety and effectiveness. Some embodiments may comprise a PVDF polymer and plasticizers.

[0024] Embodiments of the disclosure may use an aqueous PVDF polymer dispersion with plasticizer and other additives to form and/or coat at least a portion of the gloves, wherein the combination of these materials may provide excellent chemical permeation resistance and may be easily manufactured using an aqueous glove dipping processes and equipment. This produces a seam free, three dimensional glove having unique properties provided by the PVDF polymer dispersion in combination with the other materials.

[0025] The materials used to form the glove may generally comprise a PVDF polymer, a plasticizer, and optionally, one or more additives. The PVDF polymer may be cross-linkable, hydroxyl functional polymer capable of being dispersed in an aqueous solution. In an embodiment, the PVDF polymer may comprise a PVDF polymer. The plasticizer may comprise any suitable plasticizer that is compatible with the PVDF polymer. In an embodiment, the plasticizer may comprise Sebacate. Various additives including additional polymers or resins may be included within the material to provide the desired product properties. For example, additional components may be included to provide a desired flexibility, toughness, wear resistance, color, specific chemical resistance, or the like. The additional components may be compatible with the dispersion process used to form the gloves, for example, by being water soluble or dispersible. In an embodiment, the additional components may comprise additional polymers (e.g., an acrylic resin), an adhesive, a colorant, an anti-microbial agent, a fiber, a fragrance, or any combination thereof.

[0026] With the formation process, a coagulant may be used to aid in coagulating the PVDF polymer from the aqueous solution. Various coagulants suitable for coagulating the polymer from solution may be used. In an embodiment, the coagulant may comprise calcium nitrate.

[0027] Initial physical property testing and chemical permeation testing of gloves formed as described above have shown properties that are suitable for use in making chemical resistant gloves. As used herein, a glove may refer to a five-fingered covering for the hand, and optionally, a portion of the forearm. A glove may also refer to a mitten having only a thumb or any combination of fingers from zero to five. The materials described herein may also be used to form various protective devices including, but not limited to, an apron, a coat, a hat, a scarf, a sock, mask, or the like. Additionally, PVDF polymers may potentially be used to improve/strengthen other gloves or protective devices including general purpose gloves, fabric lined gloves, glove box gloves, coated fabric aprons, and the like. The PVDF polymer with its inherent toughness and chemical resistance may also be used in other fabric supported industries and glove box glove applications.

[0028] In some embodiments, the gloves may be made (or formed) using an aqueous dipping process modified for the materials described herein (e.g., as described in FIG. 1). This economical process will provide a cost effective glove that can be used in chemical applications that require high performance chemical permeation resistance and excellent physical properties.

[0029] An exemplary embodiment of the disclosure includes the specifications and steps of a process of forming the three-dimensional glove. For example, the materials used to form the glove are described below in Tables 1 and 2. The material used to form the glove may comprise a PVDF acrylic material in the ratios described below in Table 1. The PVDF material may also be mixed with a plasticizer, such as Sebacate. Additionally, a coagulant material may be mixed with the PVDF and plasticizer, wherein the coagulant comprises a specific gravity of 1.30 at a temperature of approximately 110 degrees Fahrenheit.

Table 1

[0030] In some embodiments, the PVDF material may comprise a KYNAR® (or KYNAR Aquatic®) latex material. In some embodiments, the KYNAR® latex material may comprise at least 60% fluorine by weight. In some embodiments, the KYNAR® latex material may be emulsified to create a hybrid PVDF/acrylic dispersion, which may be about 45 percent by weight (wt%) solids. In other embodiments, the material may be approximately 40 wt% solids. In some embodiments, the KYNAR® latex material may comprise a PVDF to Acrylic weight ratio of approximately 70:30. In other embodiments, the KYNAR® latex material may comprise a PVDF to Acrylic weight ratio of approximately 50:50. In some embodiments, the KYNAR® latex material may comprise a minimum film forming temperature (MFFT) of approximately 15 degrees Celsius (or approximately 59°F). In some embodiments, the KYNAR® latex material may comprise enhanced hardness, and enhanced solvent and abrasion resistance.

[0031] In some embodiments include a method for forming a chemical resistant glove which may comprise: preparing a dippable coagulant solution, dipping a glove form in the coagulant solution (to form a portion of a glove material); drying the glove form with the coagulant disposed thereon; preparing an aqueous solution of the polymer dispersion along with any plasticizer(s) and any optional components; dipping the glove form in the aqueous polymer dispersion so that a continuous layer of the material is deposited on the glove form to form a portion of the glove material; removing the glove form from the aqueous solution; drying the dispersion; and removing the glove material from the glove form. The resulting glove may be seamless, and the chemically resistant material may have a thickness of between about 1 mil and about 20 mils, or between about 5 mils and about 15 mils, or about 10 mils (i.e., one-thousandth of an inch).

[0032] In the embodiment shown in FIG. 1, a method 100 for forming a chemically resistant glove is described. Variations of similar methods may be used to form a glove having chemically resistant properties, wherein the follow method 100 describes one exemplary embodiment.

[0033] At step 102, a water bath may be preheated up to 110°F when using a water based coagulant. At step 104, one or more porcelain hand form may be preheated to approximately 115-120°F, and the porcelain hand form may be dipped into the coagulant that is heated to 110°F. At step 106, the porcelain hand form may be dipped into the coagulant at a rate of 0.5 inches per second (“/sec) and then removed from the coagulant at a rate of 0.5 inches per second. Additionally, the porcelain hand form may tend up for 10 seconds and then tend down for 10 seconds. At step 108, the form covered in coagulant may be placed into an oven (e.g. a Wunan oven) for approximately 30 minutes at approximately 140°F to dry. At step 110, the coagulated form may be removed from the drying oven, and dipped into a PVDF-acrylic dispersion material at 0.5”/sec with a dwell time of approximately 1 minute and an exit speed of 0.5”/sec. Step 110 may be repeated as necessary to form a film with a desired thickness of PVDF-acrylic material on the glove form.

[0034] At step 112, the film and the glove form may be tended, fingers up, for approximately 10 seconds, then the film and glove form may be tended, fingers down, for approximately 10 seconds, and then may be rotated 360 degrees for approximately 2 minutes. At step 114, the film formed on the glove form may be leached in water at 110°F for approximately 20 minutes. At step 116, the film may be dried in an oven for approximately 2 hours at 140°F. At step 118, the now formed glove on the glove form may be removed from the oven and cooled down to room temperature (approximately 75-78°F). Then, at step 120, the glove may be stripped from the glove form using a talc and water dispersion.

[0035] In some embodiments, the method 100 may comprise further drying steps, such as patting dry, turning the glove inside out to dry, and/or further drying in an oven. In some embodiments, while dipping the glove form, the form may be rotated. In some embodiments, the glove form may be fabric lined to provide a fabric lining inside the glove formed by the dipping method 100, wherein the method may optionally comprise applying a fabric lining to the porcelain form before dipping. In an alternative embodiment, the method 100 may comprise attaching a fabric lining to the glove after the dipping and drying process. In some embodiments, the method 100 may optionally comprise attaching a fabric lining to the exterior of the glove formed by the dipping method, and then inverting the glove with the attached fabric lining, thereby placing the fabric lining on the interior of the glove.

[0036] In some embodiments, some of the steps of the method 100 may be varied to create different thicknesses of glove. For example, the specific gravity of the coagulant used may be increased or decreased to affect the thickness of the glove. Additionally, the dwell time and/or dip speed may be increased or decreased to affect the thickness of the glove, as may be understood by one of skill in the art.

[0037] Additionally, the form used in the dipping process may vary in size and shape depending on the requirements of the user. For example, the form may be a left hand shape, a right hand shape, or an ambidextrous shape. Also, the form may vary in any size of glove available.

[0038] In some embodiments, the length of the glove may be between approximately 10 inches and 20 inches. In some embodiments, the length of the glove may be approximately 12 inches. In some embodiments, the thickness of the glove may be between approximately 4 mils and 40 mils. In some embodiments, the thickness of the glove may be between approximately 10 mils and 30 mils. In some embodiments, the thickness of the glove may comprise approximately 15 mils. In some embodiments, the thickness of the glove may comprise approximately 10 mils. The length and thickness of the glove may be adjusted based on the desired use of the glove.

[0039] In some embodiments, the glove may be designed for chemical resistance against a number of chemicals. The glove may be tested to ensure resistance against these chemicals. For example, as illustrated in Table 2, the glove may be tested with the following chemicals: Acetone, Acetonitrile, Carbon Disulphide, Dichloromethane, Diethylamine, Methyl Acetate, n- Heptane, Methanol, Sodium Hydroxide 40%, Sulfuric Acid 96%, Tetrahydrofuran, and Toluene. Table 2 shows the chemical break through time in minutes for a first glove (Glove A), a second glove (Glove B), and a third glove (Glove C) when the gloves are in contact with the above listed chemicals. The current embodiment is illustrated by Glove A, which may comprise a PVDF/sebacate glove with a thickness of 15 mils. In some embodiments, Glove B may comprise a Fluoropolymer (4 mils outer layer)/butyl (8 mils inner layer). In some embodiments, Glove C may comprise a Butyl glove with a thickness of 20 mils.

[0040] As can be seen in Table 2, Glove A is compared to Gloves B and C. Glove A has a comparable chemical break through time with Gloves B and C for the following chemicals: Diethylamine, Sodium Hydroxide 40%, and Tetrahydrofuran. Glove A has a comparable chemical break through time with Glove B for n-Heptane. Glove A is superior to Glove B for the following chemicals: Diethylamine and Carbon Disulphide. Glove A is superior to Glove C for Carbon Disulphide, n-Heptane and Toluene.

Table 2

[0041] While various embodiments in accordance with the principles disclosed herein have been shown and described above, modifications thereof may be made by one skilled in the art without departing from the spirit and the teachings of the disclosure. The embodiments described herein are representative only and are not intended to be limiting. Many variations, combinations, and modifications are possible and are within the scope of the disclosure. Alternative embodiments that result from combining, integrating, and/or omitting features of the embodiment(s) are also within the scope of the disclosure. Accordingly, the scope of protection is not limited by the description set out above, but is defined by the claims which follow, that scope including all equivalents of the subject matter of the claims. Each and every claim is incorporated as further disclosure into the specification and the claims are embodiment(s) of the present invention(s). Furthermore, any advantages and features described above may relate to specific embodiments, but shall not limit the application of such issued claims to processes and structures accomplishing any or all of the above advantages or having any or all of the above features.

[0042] Additionally, the section headings used herein are provided for consistency with the suggestions under 37 C.F.R. 1.77 or to otherwise provide organizational cues. These headings shall not limit or characterize the invention(s) set out in any claims that may issue from this disclosure. Specifically and by way of example, although the headings might refer to a“Field,” the claims should not be limited by the language chosen under this heading to describe the so- called field. Further, a description of a technology in the“Background” is not to be construed as an admission that certain technology is prior art to any invention(s) in this disclosure. Neither is the“Summary” to be considered as a limiting characterization of the invention(s) set forth in issued claims. Furthermore, any reference in this disclosure to“invention” in the singular should not be used to argue that there is only a single point of novelty in this disclosure. Multiple inventions may be set forth according to the limitations of the multiple claims issuing from this disclosure, and such claims accordingly define the invention(s), and their equivalents, that are protected thereby. In all instances, the scope of the claims shall be considered on their own merits in light of this disclosure, but should not be constrained by the headings set forth herein.

[0043] Use of broader terms such as comprises, includes, and having should be understood to provide support for narrower terms such as consisting of, consisting essentially of, and comprised substantially of. Use of the term“optionally,”“may,”“might,”“possibly,” and the like with respect to any element of an embodiment means that the element is not required, or alternatively, the element is required, both alternatives being within the scope of the embodiment(s). Also, references to examples are merely provided for illustrative purposes, and are not intended to be exclusive.

[0044] While several embodiments have been provided in the present disclosure, it should be understood that the disclosed systems and methods may be embodied in many other specific forms without departing from the spirit or scope of the present disclosure. The present examples are to be considered as illustrative and not restrictive, and the intention is not to be limited to the details given herein. For example, the various elements or components may be combined or integrated in another system or certain features may be omitted or not implemented.

[0045] Also, techniques, systems, subsystems, and methods described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present disclosure. Other items shown or discussed as directly coupled or communicating with each other may be indirectly coupled or communicating through some interface, device, or intermediate component, whether electrically, mechanically, or otherwise. Other examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the spirit and scope disclosed herein.

Claims

CLAIMS What is claimed is:

1. A method for forming a chemical resistant glove comprising:

preheating a coagulant material to approximately 110 degrees Fahrenheit (°F);

preheating a glove form to approximately 115°F;

dipping the glove form into the coagulant material;

drying the coagulant on the glove form;

dipping the glove form having the coagulant into a polyvinylidene fluoride (PVDF) and acrylic dispersion material to form at least a film on the glove form; leaching the glove form having the film disposed thereon;

drying the glove form having the film disposed thereon, wherein the dried film forms a glove material; and

removing the glove material from the glove form.

2. The method of claim 1, wherein the coagulant comprises specific gravity of approximately 1.30.

3. The method of claim 1, wherein dipping the glove form into coagulant comprises:

dipping the glove form into coagulant at a rate of 0.5 inches per second (”/sec);

removing the glove from the coagulant at a rate of 0.5”/sec;

repeating the dipping and removing for a predetermined number of dips to form the desired thickness of coagulant on the glove form;

tending the glove form up for 10 seconds; and

tending the glove form down for 10 seconds.

4. The method of claim 1, wherein drying the coagulant on the glove form comprises drying the coagulant on the glove form for approximately 30 minutes at approximately 140°F. 5. The method of claim 1, wherein dipping the glove form having the coagulant into the PVDF and acrylic dispersion material comprises:

dipping the glove form into PVDF and acrylic dispersion material at a rate of 0.5 inches per second (”/sec);

dwelling the glove form in the PVDF and acrylic dispersion material for approximately 1 minute;

removing the glove from the PVDF and acrylic dispersion material at a rate of 0.

5”/sec; and

repeating the dipping, dwelling, and removing for a predetermined number of dips to form the desired thickness of film on the glove form.

6. The method of claim 1, wherein drying the glove form having the film disposed thereon comprises drying the glove form having the film disposed thereon for approximately 2 hours at approximately 140°F.

7. The method of claim 1 further comprising adding fabric layer to the glove material.

8. The method of claim 1 further comprising cooling the glove form having the film disposed thereon to room temperature before removing the glove material from the glove form.

9. A method for forming a chemical resistant glove comprising:

dipping a glove form in a coagulant;

drying the coagulant on the glove form;

dipping the glove form having the coagulant in an aqueous dispersion comprising polyvinylidene fluoride (PVDF) polymer to form a portion of the glove material on the glove form;

drying the glove form having the dispersion disposed thereon; and

removing the glove material from the glove form.

10. The method of claim 9, wherein the coagulant comprises calcium nitrate.

11. The method of claim 9, wherein the glove form is a porcelain glove form.

12. The method of claim 9, wherein the aqueous dispersion comprises a vinyl resin.

13. The method of claim 9, wherein the aqueous dispersion comprises a plasticizer.

14. The method of claim 13, wherein the plasticizer comprises sebacate.

15. The method of claim 9 further comprising disposing a fabric layer over the glove form prior to dipping the glove form in the coagulant.