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US-12623197-B2 - Sol application methods

US12623197B2US 12623197 B2US12623197 B2US 12623197B2US-12623197-B2

Abstract

A method comprising providing a sol comprising a solvent; contacting the sol with a precipitation initiator to initiate precipitation of the sol, wherein the precipitation initiator is different to the solvent; and applying the precipitating sol to a product. The methods of the invention may be used with sols comprising a solvent, a metal alkoxide, and optionally a biopolymer and/or a catalyst, with alkoxides comprising metals, organically modified alkoxides comprising metals, alkoxides comprising metalloids, and organically modified alkoxides comprising metalloids all being encompassed by the term ‘metal alkoxide’. Also disclosed is an apparatus for use in the method comprising a first storage vessel; a second storage vessel; one or more pumps; and one or more delivery means.

Inventors

  • Fanya Ismail

Assignees

  • Green Sol-Gel Ltd.

Dates

Publication Date
20260512
Application Date
20200212

Claims (20)

  1. 1 . A method comprising: (i) providing a sol comprising a solvent and a metal alkoxide; (ii) contacting the sol with a precipitation initiator to initiate precipitation of the sol, wherein the precipitation initiator is different to the solvent; and (iii) applying the precipitating sol to a product.
  2. 2 . The method of claim 1 , wherein the precipitation initiator comprises water or ethanol.
  3. 3 . The method of claim 1 , wherein the precipitation initiator comprises one or more functional additives.
  4. 4 . The method of claim 1 , wherein the sol comprises one or more functional additives.
  5. 5 . The method of claim 3 , wherein the one or more functional additives comprise a photo-initiator, resin, oils, dye, salt, mineral or other inorganic particles, surfactant, composite particle, and/or metal.
  6. 6 . The method of claim 1 , wherein the sol comprises one or more biopolymers.
  7. 7 . The method of claim 6 , wherein one or more biopolymers comprises a starch, modified starch, flour, or a modified flour.
  8. 8 . The method of claim 1 , wherein the metal of the metal alkoxide comprises silicon, titanium, aluminium, zirconium, tin, or any combination thereof.
  9. 9 . The method of claim 1 , wherein the metal of the metal alkoxide comprises silicon, titanium, aluminium, zirconium, or any combination thereof.
  10. 10 . The method of claim 1 , wherein the metal of the metal alkoxide comprises silicon, titanium, or any combination thereof.
  11. 11 . The method of claim 1 , wherein the metal of the metal alkoxide comprises silicon.
  12. 12 . The method of claim 1 , wherein the metal of the metal alkoxide comprises titanium.
  13. 13 . The method of claim 1 , wherein the alkoxide is selected from the group consisting of: Ti(isopropoxy) 4 , Al(isopropoxy) 3 , Al(sec-butoxy) 3 , Zr(n-butoxy) 4 , Zr(n-propoxy) 4 , n-propyltriethoxysilane, tetrapropyl orthosilicate, titanium(IV) tert-butoxide, titanium(IV) isopropoxide, triethyloxysilane, methyltriethyloxysilane, triethoxy(octyl)silane, phenyl-triethoxysilane, titanium(iv) ethoxide, triethoxy-silylcyclopentane, (3-glycidyloxypropyl) trimethoxysilane, cyclopentyltriethoxysilane, 3-amino-propyltriethoxysilane, triethoxy-3-(2-imidazolin-1-yl)propylsilane, and any combination thereof.
  14. 14 . The method of claim 1 , wherein the alkoxide is selected from the group consisting of: tetrapropyl orthosilicate, titanium(IV) tert-butoxide, titanium(IV) isopropoxide, triethyloxysilane, methyltriethyloxysilane, triethoxy(octyl)silane, phenyl-triethoxysilane, titanium(iv) ethoxide, triethoxy-silylcyclopentane, (3-glycidyloxypropyl) trimethoxysilane, cyclopentyltriethoxysilane, or any combination thereof.
  15. 15 . The method of claim 1 , wherein the alkoxide is selected from the group consisting of: Si(OR) 4 , Ti(OR) 4 , Al(OR) 3 , Zr(OR) 3 , Sn(OR) 4 , R c —Si(OR) 3 , R c —Ti(OR) 3 , R c —Al(OR) 2 , R c —Zr(OR) 2 and R c —Sn(OR) 3 , or any combination thereof.
  16. 16 . The method of claim 1 , wherein the alkoxide is selected from the group consisting of: Ti(isopropoxy) 4 , Al(isopropoxy) 3 , Al(sec-butoxy) 3 , Zr(n-butoxy) 4 , Zr(n-propoxy) 4 , and n-propyltriethoxysilane based alkoxides, and any combination thereof.
  17. 17 . The method of claim 1 , wherein the alkoxide is selected from the group consisting of: tetraethoxysilane, phenyltriethoxysilane, methyltriethyloxysilane, and any combination thereof.
  18. 18 . The method of claim 1 , wherein the solvent comprises one or more organic solvents.
  19. 19 . The method of claim 18 , wherein the one or more organic solvents comprise an alcohol.
  20. 20 . The method of claim 19 , wherein the alcohol is selected from the group consisting of: methanol, ethanol, isopropanol, butanol, ethylene glycol, or any combination thereof.

Description

The invention relates to the application of colloidal solutions (known as sols) to products and methods of performing the same. More particularly, the invention relates to methods of using sols to impart desirable properties to products. Paper, cardboard, wood and other materials are commonly used as packaging for commercial products. The material properties of a product, such as the permeability of packaging materials to water, oils and other fluids may be controlled by using impermeable plastic materials or composites. In many industries such as the food and drink sector, plastics may be applied to otherwise permeable media to facilitate the retention of liquid products within a particular packaging item. Similar methods may also be used to prevent the ingress of fluid into an item that may become compromised by exposure to water, air or other fluids. The plastic materials used in these applications are generally manufactured from hydrocarbon feedstocks and their manufacture presents an associated environmental cost. The materials or chemicals used to manufacture such plastics and the associated by-products may also be toxic. Some plastics may also degrade over time to produce microplastics or through use to release potentially harmful species. Consequently, there are ongoing health and environmental concerns in relation to many common packaging materials. Commercial manufacturing operations generally seek to produce the highest quantity of products at the lowest cost without sacrificing the provision of quality deemed to be acceptable or desirable by the market into which the product is sold. Plastics remain a low cost commodity and worldwide manufacturing has established well developed and efficient methods to utilise and manipulate plastic materials since their widespread adoption in manufacturing in the 1940s and 1950s. It is generally accepted that a successful plastic replacement technology would be required to be operable at a similar cost and equivalent or reduced ease of use to be accepted by the manufacturing industry. There is therefore a commercial need for an environmentally friendly plastic replacement technology that imparts the same benefits as plastic at an equivalent cost that may be easily adopted in a manufacturing environment. Sol technology, or sol gel technology, provides a non-toxic alternative to some plastic materials. In this context, the term ‘sol’ refers to a dispersion of colloidal particles in a liquid solvent. Many sols formed from small colloidal particles are substantially clear and colourless. For example, sols formed from silicon-based functional materials will generally be clear and colourless as the particles forming the sol are sufficiently small that they do not scatter light. Some sols formed from larger particles may be coloured and/or at least partially opaque. For example, sols formed from titanium-based functional materials may be visibly white. Sols may form impermeable and/or anti-microbial and/or alternatively functional coating compositions when applied to a range of materials. Consequently, sols may be used as a barrier and/or as an anti-microbial coating composition and may provide other functionalities such as hydrophobicity, oleophobicity, anti-fouling, anti-biofouling, stain resistance, optical transparency and adhesion promotion. Sols may comprise readily available natural materials that ensure the resulting sols are inexpensive. Additionally, sols may be directly applied to a surface, i.e. without the surface needing to undergo a special preparation process, ensuring that sols are easy to use. Furthermore, some sols have been shown to provide a durable and thermally resistant coating, demonstrating that sols may form resilient and long-lasting functional coatings. The inventor of the present invention has appreciated that it is possible to utilise a reduced quantity or concentration of sols to impart desirable properties to products that are also achieved by utilising the sol on a 100% basis. The retention of advantageous functional properties by using reduced quantities or concentrations of sols is surprising as it may have otherwise been assumed that lower quantities of sols would be unable to form the extensive crosslinking networks that may be required to achieve a desired functionality, such as impermeability. The inventor of the present invention has further appreciated that it is possible to utilise a sol that is in the process of precipitating to impart functional characteristics to a product or a coating thereon. The initiation of the precipitation of a sol using a precipitation initiator causes a previously stable colloidal sol suspension to become unstable. The inventor has understood that sols applied to products early in the process of precipitation will still form functional network structures with functionality comparable to those formed when the stable sol is used without further additives or components. A sol in the process of precip