WO2021229444A1 - Nouveau masque facial biodégradable amélioré ayant des propriétés intrinsèques virucides, hydrophobes et hydrophiles comportant des boucles latérales réglables - Google Patents

Nouveau masque facial biodégradable amélioré ayant des propriétés intrinsèques virucides, hydrophobes et hydrophiles comportant des boucles latérales réglables Download PDF

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Publication number
WO2021229444A1
WO2021229444A1 PCT/IB2021/054018 IB2021054018W WO2021229444A1 WO 2021229444 A1 WO2021229444 A1 WO 2021229444A1 IB 2021054018 W IB2021054018 W IB 2021054018W WO 2021229444 A1 WO2021229444 A1 WO 2021229444A1
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WO
WIPO (PCT)
Prior art keywords
fabric
face mask
filtration
face
layer
Prior art date
Application number
PCT/IB2021/054018
Other languages
English (en)
Inventor
Gamini RAJAPAKSE
Chaminda HERATH
Nirodha THILAKARATHNE
Dharshana SENARATHNA
Namal ABEYSOORIYA
Original Assignee
University Of Peradeniya
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University Of Peradeniya filed Critical University Of Peradeniya
Publication of WO2021229444A1 publication Critical patent/WO2021229444A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/08—Filter cloth, i.e. woven, knitted or interlaced material
    • B01D39/083—Filter cloth, i.e. woven, knitted or interlaced material of organic material
    • A—HUMAN NECESSITIES
    • A41—WEARING APPAREL
    • A41D—OUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
    • A41D13/00—Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches
    • A41D13/05—Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches protecting only a particular body part
    • A41D13/11—Protective face masks, e.g. for surgical use, or for use in foul atmospheres
    • A41D13/1192—Protective face masks, e.g. for surgical use, or for use in foul atmospheres with antimicrobial agent
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
    • A62B23/00—Filters for breathing-protection purposes
    • A62B23/02—Filters for breathing-protection purposes for respirators
    • A62B23/025—Filters for breathing-protection purposes for respirators the filter having substantially the shape of a mask
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/02—Types of fibres, filaments or particles, self-supporting or supported materials
    • B01D2239/0258—Types of fibres, filaments or particles, self-supporting or supported materials comprising nanoparticles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/02—Types of fibres, filaments or particles, self-supporting or supported materials
    • B01D2239/0266—Types of fibres, filaments or particles, self-supporting or supported materials comprising biodegradable or bio-soluble polymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0414—Surface modifiers, e.g. comprising ion exchange groups
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0414—Surface modifiers, e.g. comprising ion exchange groups
    • B01D2239/0421—Rendering the filter material hydrophilic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0414—Surface modifiers, e.g. comprising ion exchange groups
    • B01D2239/0428—Rendering the filter material hydrophobic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0442—Antimicrobial, antibacterial, antifungal additives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
    • B01D2239/0604—Arrangement of the fibres in the filtering material
    • B01D2239/0613—Woven
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
    • B01D2239/065—More than one layer present in the filtering material

Definitions

  • the face mask is washable, ironed and reused. They are reusable at least up to 20 washing cycles
  • the outer layer cotton has been nanotechnologically engineered to have superhydrophobic properties as the way lotus leaf surface has.
  • the outer layer therefore repels any aerosol particle containing the virus, any water droplets, blood droplets and stain and remains fresh for several days.
  • the middle layer cotton fabric has been nanotechnologically modified by chemically attaching microparticles to cover the pores down to 300 nm.
  • microparticle surfaces are positively charged these surfaces attract the negatively charged viral envelope and bin electrostatically on their surfaces.
  • the middle layer prevents the penetration of the virus by electrostatic filtration also.
  • the inner layer is made of hydrophilic cotton to make sure quick absorption of moisture and carbon dioxide in the exhaled air and evaporate out of the headspace between the mask and the face.
  • the materials used are chemically bound to respective fabrics so as not to detach and inhale by the user.
  • the nanoparticles cause multimodal virucidal effects via photocatalytic activities and Contact Killing, A soft inner layer with moisture absorption leaving the filter area in contact with mouth and nose free of fluid clogging, An added layer of activated charcoal filtering chemical vapor and odor control, to be used in removable filters of gas mask type PPE, as well as for exhaust filtration in mechanical ventilators and air conditioners Cleanable rigid filter layer of Copper/ Bronze which has backup virucidal effects is planned for equipment with exhaust. This involves five tasks as described below.
  • the outer layer of three-ply masks should be made from a hydrophobic/superhydrophobic fabric to enable it to be able to repel any charged particles such as viruses and moisture.
  • the hydrophobic/superhydrophobic property ensures stain-resistance and hence increased durability of the mask with its fresh and clean appearance for several days. It also prevents moisture seeping through the top layer to reach the middle layer. However, since the pore structure of the fabric is reserved the respiration is not objected by this layer. This can be achieved in many ways.
  • Figure 1 shows the contact angles of a water droplet on cotton, modal and viscose fabrics.
  • Figure 1 (a) shows optical images of a water droplet on fabric surface and 1 (b) shows the image obtained in the contact angle measurement.
  • the measured contact angle values for the different systems are depicted in Table (1).
  • This task involves modification of woven cotton fabric of GSM 188 (Grey cloth) with suitable materials to reduce pore size of the fabric below 300 nm. This is achieved by entrapping and chemically bonding different types of nano- to micro-particles within these pores.
  • the nano- to micro-particles used in this invention are derived from commonly available naturally occurring minerals.
  • the types of nano- to micro-particles used are titanium dioxide, zinc oxide, calcium carbonate and magnesium oxide, all of which are non-toxic, bio-compatible, non-hazardous and environmentally-friendly.
  • Chemical attachment of the nanoparticles within the pores of the fabric mesh is achieved through suitable binders such as polyacrylic binder or polyurethane binder that is generally used in the textile industry. Since the particles are chemically attached to the fabric fibres, there is no risk of inhalation of these particles.
  • zinc oxide or titanium dioxide nanoparticles are used, there is an antimicrobial effect enabling the destruction of the virus.
  • Zinc oxide has its antimicrobial effects even in the dark, due to surface zinc ions and through photocatalytic activity below 380 nm wavelengths present in sunlight or radiation emanating from operation theatre lamps. Titanium dioxide has its antimicrobial activity due to inherent photocatalytic activity below 380 nm wavelengths and the activity can be shifted to visible region by suitably modifying titanium dioxide with N-doping, S-doping and so on. Titanium dioxide nanoparticles prepared at slightly lower pH (between 5 to 6) have surface positive charge-due to adsorbed photons on the surface hydroxyl groups-enabling electrostatic attraction of viral particles (whose surfaces are negatively charged) and destructive capability due to antiviral effect of the same nanoparticles as well as metal particles used to modify cotton fabric.
  • Antiviral activity can be further enhanced by attaching copper nanoparticles which act via the so-called contact killing effect, where surface copper ions destroy the outer coating of the viral particles.
  • the known virucidal effects of the metal compounds would be accentuated hundred-fold by the increased surface area achieved by using nanometric size particles. The task can be achieved as follows.
  • a required amount of the above colloidal solution (one or more values in the range from 1 to 200 mL) was added to absolute ethanol or 100% isopropanol (one or more values in the range from 1 mL to 1 L) and thoroughly mixed.
  • Previously autoclaved fabric (10 cm x 10 cm for laboratory studies and large pieces such as rolls was dipped in the solution while stirring and heating to boiling.
  • Required amount of ethanol (strength in the range of 1% to 50% and volume in the range of 1 to 500 mL) was then added slowly while stirring and allowing the solution to boil until colloidal nanoparticle formation is completed.
  • the fabric is then removed from the solution and dried in air followed by oven drying at 100 °C to 150 °C for a few minutes.
  • Figure 2 shows optical micrographs of the (a) untreated, (b) partially-treated and (c) higher dose of treatment and (d) fully-treated cotton fabric.
  • the layer that is in immediate contact with the face is meant to give comfort to the wearer as well as to act as a barrier to prevent any pieces of debris that may have generated with wear and tear of the mask. It is quite common that repeated washing procedures applied on textiles and abrasion with various surfaces can make textiles pill to give short chain ends of fabric fibres to come to the surface and stay in a coiled configuration. This fabric filling can be minimized by a suitable chemical treatment.
  • the poplin fabric is used to make this layer of the mask and pilling is controlled by the application of an extra-thin, ⁇ 50 nm thick layer of a suitable polymeric material on the both sides of the fabric. This is done by spraying the polymeric solution on to the fabric surfaces or by screen printing the solution to the surfaces.
  • Guidance for face mask evaluation is provided in the Guidance Document of the Center for Devices and Radiological Health that involves U.S. Department of Health and Human Services, Food and Drug Administration, Center for Devices and Radiological Health, Infection Control Devices Branch, Division of Anesthesiology, General Hospital, Infection Control, and Dental Devices, Office of Device Evaluation.
  • the document is attached in the Appendix II. Accordingly the Surgical Mask and Surgical Respirator “N95 NOISH Certified” are defined as follows.
  • Surgical Mask covers the user’s nose and mouth and provides a physical barrier to fluids and particulate materials.
  • the surgical masks referenced in this guidance document include masks that are labeled as a surgical, laser, isolation, dental or medical procedure masks with or without a face shield.
  • Surgical Respirator “N95 NIOSH Certified” A surgical respirator is fitted to the user’s face, forming a seal that provides a physical barrier to fluids, particulate materials, and aerosols. If you wish to label your device “N95 NIOSH Certified,” please refer to the (NIOSH) website at http://www.cdc.gov/niosh/npptl/resources/certpgmspt/ (http://www.cdc.gov/niosh/npptl/resources/certpgmspt/) for information about NIOSH's Certification Program Support for Respirator.
  • specifications include size, dimensions, tensile strength and other specifications relevant to user needs, e.g., impact resistance.
  • Design features include tie-on or ear loops, elastic or face shield attached.
  • Mask styles include duck bill, flat pleated, cone shaped or pouch. The parameters tested are Fluid Resistance, Particulate Filtration Efficiency, Bacterial Filtration Efficiency, Differential Pressure and Flammability Class.
  • the fluid resistance is defined as the ability of the mask’s material to resist the penetration of blood and body fluids. It is measured according to the ASTM F 1862: Standard Test Method for Resistance of Surgical Mask to Penetration by Synthetic Blood. According to ASTM F 1862 test method, surgical masks are tested on a pass/fail basis at three velocities corresponding to the range of human blood pressure (80, 120, 160 mm Hg). Fluid resistance may be claimed if the device passes ASTM FI 862 at any levels. Surgical masks that show passing results at higher velocities are more fluid resistant.
  • Particle filtration challenge is to be conducted using 0.1 -micron Polystyrene Latex Spheres.
  • This in vitro test challenges the mask with un-neutralized 0.1 -micron polystyrene latex spheres and measures penetration.
  • the use of latex spheres provides an appropriately rigorous test for evaluating a sub-micron efficiency performance (ASTM F 1215-89 Standard Test Method for Determining the Initial Efficiency of Flatsheet Filter Medium in an Airflow Using Latex Spheres ).
  • the test that is used in Sri Lanka is the Quantitative evaluation of particulate permeation through face mask materials that is conducted by the Sri Lanka Institute of Nanotechnology. The test method has been described and the results are provided above.
  • BFE Bacterial Filtration Efficiency
  • Flammability Test One of the following tests can be used to determine flammability class.
  • Multilayered material within replaceable filters with superhydrophobic/hydrophobic and/or oiliophobic/omniphobic nanolayer layers advanced filtration (95% filtration at 300 nm particles) with advanced/combined virucidal nanoparticles such as combined full face mask, powered air purifying respirators.
  • Super-hydrophobic for medical/ hospital setting is required to minimize risk of fluid/ macro-droplet splashing during procedures or close patient contact.
  • the face mask according to claim 1, wherein the middle layer is fabricated by blocking the pores of cotton fabric using chemically attached titanium dioxide nano- and micro-particles to have required breathability but to filter particles of size equal to or greater than 300 nanometers by mechanical disruptions and electrostatic binding, and having chemically attached zinc oxide nanoparticles to induce viricidal activity.
  • the face mask according to claim 1, 3 and 4 wherein the middle layer is formed by chemically binding titanium dioxide microparticles to cover pores of cotton fabric down to 300 run and to electrostatically bind negatively charged viral envelope of the corona viruses including SARS CoV-2 and to destroy them by mechanically disrupting the corona virus and damaging envelopes and to destroy any bacteria by chemically bound star-shaped, rod-like or flake-like zinc oxide nanoparticles, the later is also capable of destroying viruses and bacteria by chemical and photochemical actions.
  • the face mask according to claim 1, 3 and 4, wherein the middle layer also has enhanced electrostatic filtration is achieved due to the electrostatic binding of the negatively charged viral envelopes with positively charged titanium dioxide microparticle surfaces.

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  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physical Education & Sports Medicine (AREA)
  • Respiratory Apparatuses And Protective Means (AREA)

Abstract

Les nouveaux matériaux de masque facial améliorés présentant une activité virucide inhérente ne réduisent ou n'annulent pas seulement la charge virale par inhalation, mais réduisent la transmission à la fois par voie respiratoire et par contact en contribuant à une bonne pratique hygiénique, réduisant ainsi l'impact de porteurs asymptomatiques et de patients présentant une maladie de faible intensité dans la communauté. Ceci empêche la possibilité de réinhaler l'air riche en dioxyde de carbone et donne un confort au porteur. Une amélioration variable des activités virucides, filtrantes et hydrophobes à travers de multiples couches est obtenue pour s'adapter à différentes couches de la population générale ainsi qu'au système de santé souffrant de la pandémie de COVID-19. Différents types de masques faciaux sont fabriqués sur mesure avec des degrés appropriés d'amélioration des couches externes, centrales et internes pour différents besoins selon les populations d'utilisateurs spécifiées à l'aide d'un matériau généralement disponible et à faible coût. En plus des avantages mentionnés ci-dessus, la présente invention est fabriquée à partir de matériaux biodégradables et peut être lavée plusieurs fois après utilisation, ce qui la rend rentable. Le masque est également construit de manière à pouvoir s'adapter parfaitement au visage du porteur sans aucun espace entre le visage et le masque. Des applications supplémentaires de cette invention, combinant des nanofiltrations avec des propriétés virucides par l'intermédiaire de l'utilisation de nanotechnologies, comprennent la filtration avancée de machines de ventilateur artificiel, de purificateurs d'air, de systèmes de filtration de climatiseurs et l'utilisation dans le système de santé comme dans la literie, les tenues chirurgicales, les vêtements, etc. L'utilisation des propriétés germicides compléterait les mesures habituellement mises en œuvre pour la grippe saisonnière et devrait également être considérée pour d'autres maladies transmises par voie respiratoire.
PCT/IB2021/054018 2020-05-12 2021-05-11 Nouveau masque facial biodégradable amélioré ayant des propriétés intrinsèques virucides, hydrophobes et hydrophiles comportant des boucles latérales réglables WO2021229444A1 (fr)

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LKLKP21102 2020-05-12
LK2110220 2020-05-12

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114685188A (zh) * 2022-03-18 2022-07-01 宁夏大学 一种超疏水碳化硅陶瓷膜及其制备方法
EP4299826A1 (fr) 2022-06-29 2024-01-03 Jozef Stefan Institute Procédé de préparation de matériaux textiles polymères virucides et masques faciaux virucides fabriqués à partir de ces matériaux

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070267013A1 (en) * 2006-05-22 2007-11-22 Jing-Jyr Lin Sterilizing facemask with a multi-layer filter
EP1953286A1 (fr) * 2007-02-01 2008-08-06 Nisshinbo Industries, Inc. Tissu et masque
US20080229929A1 (en) * 2007-03-22 2008-09-25 Ken Marcoon Antimicrobial filtration article
US20080264259A1 (en) * 2007-04-26 2008-10-30 Leung Wallace W Nanofiber filter facemasks and cabin filters
WO2016125173A1 (fr) * 2015-02-08 2016-08-11 Argaman Technologies Ltd. Matières en tissu antimicrobien destinées à être utilisées dans des masques de sécurité et des vêtements de protection individuelle

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070267013A1 (en) * 2006-05-22 2007-11-22 Jing-Jyr Lin Sterilizing facemask with a multi-layer filter
EP1953286A1 (fr) * 2007-02-01 2008-08-06 Nisshinbo Industries, Inc. Tissu et masque
US20080229929A1 (en) * 2007-03-22 2008-09-25 Ken Marcoon Antimicrobial filtration article
US20080264259A1 (en) * 2007-04-26 2008-10-30 Leung Wallace W Nanofiber filter facemasks and cabin filters
WO2016125173A1 (fr) * 2015-02-08 2016-08-11 Argaman Technologies Ltd. Matières en tissu antimicrobien destinées à être utilisées dans des masques de sécurité et des vêtements de protection individuelle

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114685188A (zh) * 2022-03-18 2022-07-01 宁夏大学 一种超疏水碳化硅陶瓷膜及其制备方法
EP4299826A1 (fr) 2022-06-29 2024-01-03 Jozef Stefan Institute Procédé de préparation de matériaux textiles polymères virucides et masques faciaux virucides fabriqués à partir de ces matériaux
EP4428294A2 (fr) 2022-06-29 2024-09-11 Jozef Stefan Institute Procédé de préparation de matériaux textiles polymères virucides et masques faciaux virucides fabriqués à partir de ces matériaux

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