A heat and / or light-providing arrangement, method & use

Abstract

A heat- and / or light-providing arrangement (10) comprising a combustible fuel body (14) and a combustible fuel container (12) in which at least part of the combustible fuel body (14) is contained. The combustible fuel container (12) comprises or consists of dry moulded cellulose fibres and has a minimum density of 250 kgm-3.

Description

[0001] A HEAT AND / OR LIGHT-PROVIDING ARRANGEMENT, METHOD & USE

[0002] Technical field

[0003] The present invention concerns a heat- and / or light-providing arrangement and a method for producing such a heat- and / or light-providing arrangement. The present invention also concerns the use of a material in applications requiring a non-flammable material.

[0004] Background

[0005] Arrangements for providing heat- and / or light often comprise a non-flammable combustible fuel container containing a combustible fuel body, such as a candle or a solid fuel tablet.

[0006] Combustible fuel containers are usually made of non-sustainable materials such as metals, (aluminium for example), glass, ceramics or plastic. The combustible fuel body is at least partly enclosed in the combustible fuel container. Such arrangements have found widespread use due to their ease of use, lack of dripping, and ability to provide light, or heat, or a both light and heat. In particular, tealights have become popular and are reported to constitute a very large proportion of all candles being sold.

[0007] Unfortunately, however, recycling of a combustible fuel container, such as a tealight candle container, is often cumbersome and therefore neglected by most consumers. For example, candle containers made of aluminium frequently contain a wick holder made of steel which should be separated from the aluminium so that each material can be recycled separately under appropriate conditions. Furthermore, the global aluminium shortage and the increasing costs associated with aluminium production make it desirable not only to recycle the aluminium used but also to find alternative materials such as eco-friendly and sustainable alternative materials.

[0008] Attempts have been made to replace the aluminium of candle containers with glass. For example, tealights have been made from stearin candles in a glass candle container. Once the stearin candle has burned down it may be replaced with a new candle thereby reusing the glass candle container. While this represents an improvement from a recycling and sustainability point of view, it also requires some effort from the user. For example, it is envisaged that the user has to clean the glass candle-container and measures may also have to be taken in order not to break the glass container, thereby making handling time consuming and inconvenient. Moreover, the glass candle container may overtime become scratched and less visually appealing.

[0009] Furthermore, candle containers can get extremely hot and may damage a surface on which they are placed, and candle containers made of plastic or glass can shatter without warning.

[0010] Summary

[0011] It is an object of the present invention to provide an improved heat- and / or lightproviding arrangement comprising a combustible fuel container and a combustible fuel body.

[0012] This object is achieved by a heat- and / or light-providing arrangement having the features recited in claim 1. The heat- and / or light-providing arrangement comprises a combustible fuel body and a combustible fuel container in which at least part of the combustible fuel body is contained. The combustible fuel container comprises or consists of dry moulded cellulose fibres and has a minimum density of 250 kgnr3(at 25°C and 101.325 kPa). At least part of the combustible fuel body is thereby in direct contact with the combustible fuel container.

[0013] The inventor has surprisingly found that such a combustible fuel container is not flammable. When the combustible fuel container is exposed to an ignition source such as a flame, a spark, or heat, it retains its structural integrity and does not melt or degrade but only chars under direct exposure to fire, which makes it suitable for use as a combustible fuel container. Additionally, when the combustible fuel body burns and melts, the molten combustible fuel can be brought into direct contact with at least one surface of the combustible fuel container and remain in direct contact with the least one surface without compromising the structural integrity of the combustible fuel container. Furthermore, the combustible fuel body can be filled with liquid combustible fuel during the production of the heat- and / or light-providing arrangement.

[0014] The claimed high density of the combustible fuel container reduces the risk that combustible material, such molten wax, from the combustible body, penetrates the combustible fuel container. This not only makes the combustible fuel container more leak-proof but reduces the risk that the combustible fuel container will catch fire during the use of the heat- and / or light-providing arrangement. Material comprising or consisting of dry moulded cellulose fibres having the claimed minimum density is therefore suitable for use as a combustible fuel container in a heat- and / or lightproviding arrangement. Furthermore, such a combustible fuel container not only complies with fire safety but is easy to recycle, environmentally friendly, sustainable, re-usable, robust and provides a thermally insulating barrier around at least part of a combustible fuel body.

[0015] According to an embodiment the combustible fuel container has a minimum density of 300 kgnr3, or a minimum density of 400 kgnr3, or a minimum density of 500 kgnr3, or a minimum density of 600 kgnr3, or a minimum density of 700 kgnr3, a minimum density of 800 kgnr3, or a minimum density of 900 kgnr3, or a minimum density of 1000 kgnr3or higher. According to an embodiment, at least part of a combustible fuel container may have a density up to 1500 kgrrn3.

[0016] According to an embodiment the combustible fuel container has a maximum density of 1500 kgnr3, or a maximum density of 1400 kgnr3, or a maximum density of 1300 kgnr3, or a maximum density of 1200 kgnr3, or a maximum density of 1100 kgnr3, or a maximum density of 1000 kgnr3, or a maximum density of 900 kgnr3, or a maximum density of 800 kgnr3, a maximum density of 800 kgnr3, or a maximum density of 700 kgnr3, or a maximum density of 600 kgnr3.

[0017] There is also provided a heat- and / or light-providing arrangement wherein the combustible fuel container comprises at least one additive and / or coating, such as a fire-retardant additive and / or coating or a binder, and / or a combustible fuel body- material-penetration-preventing additive and / or coating. Such an additive or coating may further enhance the fire-retardant and / or combustible fuel body-material- penetration-preventing properties of the combustible fuel container, and thereby further enhance the fire safety of the heat- and / or light-providing arrangement. Additionally, the high density of the combustible fuel container limits or prevents the penetration of fire-retardant coatings and / or combustible fuel body-material- penetration-preventing coatings into the combustible fuel container, whereby such coatings form an outer shell around the combustible fuel container.

[0018] Alternatively, there is provided a heat- and / or light-providing arrangement wherein the combustible fuel container is free of an additive, such as free of a fire-retardant additive and / or free of a combustible fuel body material-penetration-preventing additive.

[0019] Additionally, or alternatively, there is provided a heat- and / or light-providing arrangement wherein at least one surface (i.e. at least one whole surface or at least one part of a surface) of the combustible fuel container, or the entire combustible fuel container, is free of a coating, such as free of a fire-retardant coating and / or free of a combustible fuel body material-penetration-preventing coating.

[0020] There is also provided a heat- and / or light-providing arrangement wherein the combustible fuel body is a solid combustible fuel body, and the combustible fuel container is arranged to contain at least part of the solid combustible fuel body, such as at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90% or the entire solid combustible fuel body.

[0021] There is further provided a heat- and / or light-providing arrangement wherein at least one of the following has a surface that faces or contacts the combustible fuel body material: the combustible fuel container; the at least one coating.

[0022] There is also provided a heat- and / or light-providing arrangement wherein the combustible fuel body comprises at least one wick, and optionally at least one wick holder. A combustible fuel body may namely comprise at least one candle.

[0023] The heat- and / or light-providing arrangement according to the present invention may comprise at least one combustible fuel body having a maximum height (i.e., the height of the combustible fuel body before it is lit) and a maximum width (i.e., the width of the combustible fuel body before it is lit), whereby the maximum height of the combustible fuel body is less than or equal to the maximum width of the combustible fuel body. Alternatively, or additionally, the heat- and / or light-providing arrangement may be configured to comprise at least one combustible fuel body having a maximum height that is greater than its maximum width. The heat- and / or light-providing arrangement may be one or more of the following: a tealight, a votive candle, a grave candle, a filled candle, an outdoor candle, single-use heating or cooking equipment, portable heating or cooking equipment, such as a burner for a portable heater or stove. A heat- and / or light-providing arrangement may be used to provide a scent, and / or may be used for celebration or votive purposes.

[0024] The present invention also concerns a method for producing a heat- and / or lightproviding arrangement, such as a heat- and / or light-providing arrangement according to any of the embodiments described herein.

[0025] The method for producing a heat- and / or light-providing arrangement comprises producing a combustible fuel container by providing a dry blank of cellulose fibres, bringing the dry blank of cellulose fibres into contact with a forming surface of a forming tool, pressing the forming surface of the forming tool against the dry blank of cellulose fibres with a pressure of at least 1 MPa and heating the dry blank of cellulose fibres to a temperature of at least 100°C before and / or during the pressing, thereby producing a combustible fuel container comprising dry moulded cellulose fibres and having a minimum density of 250 kgnr3. The method also comprises placing at least part of a combustible fuel body in the combustible fuel container.

[0026] The combination of applying a pressure of at least 1 MPa and heating to a temperature of at least 100°C results in the formation of hydrogen bonds that bind the cellulose fibres of the combustible fuel container together.

[0027] Such a dry moulding method is advantageous since it offers automated, high volume and efficient production, and the flexibility to tailor the combustible fuel container design. Cycle times in dry moulding processes are short and in-line recycling allows material usage to be maximised. Additionally, since pressure and heat, are applied to a dry blank of cellulose fibres to shape and form the desired product, dry moulding does not rely on the use of a liquid or wet medium unlike traditional wet moulding processes. Dry moulding is consequently a sustainable alternative to wet moulding due to the advantage of reduced water and energy consumption, making it more environmentally friendly for industrial applications than wet forming.

[0028] The applied pressure may be a pressure of 1- 100 MPa or higher, such as a pressure of l-5MPa, or a pressure of at least 5 MPa, or at least 10 MPa, or at least 15 MPa, or at least 20 MPa, or at least 25 MPa, or at least 30 MPa, or at least 40 MPa, or at least 50 MPa, or at least 60 MPa, or at least 70 MPa, or at least 80 MPa, or at least 90 MPa. The applied pressure may be an isostatic pressure or a non-isostatic pressure. The higher the pressure at which the dry blank of cellulose fibres is pressed, the higher the minimum density of the combustible fuel container will be.

[0029] The applied temperature may be at least 150°C, or 100-300°C, or 100-200°C, or 150- 180°C.

[0030] There is further provided a method that comprises one or more of the following:

[0031] - calendering the dry blank of cellulose fibres prior to pressing,

[0032] - providing cellulose fibres by milling cellulose-containing material, and optionally shredding the cellulose-containing material prior to milling, - adding at least one additive, such as a fire-retardant additive or a binder to the cellulose fibres, optionally homogeneously mixing the cellulose fibres with the at least one additive,

[0033] - coating at least part of a surface of the dry blank with at least one coating, such as a fire-retardant coating or a combustible fuel body-material-penetration preventer coating,

[0034] - cutting the dry blank of cellulose fibres prior to pressing,

[0035] - cutting the dry moulded combustible fuel container while it is in the forming tool,

[0036] - cutting the dry moulded combustible fuel container after pressing,

[0037] - feeding any excess cellulose-containing material back into the process to recycle any waste products,

[0038] - using a forming tool comprising a compressible or deformable material that allows the forming surface to be re-shaped during compression / deformation.

[0039] The present invention also concerns the use of material comprising or consisting of dry moulded cellulose fibres and having a minimum density of 250 kgnr3according to any of the embodiments described herein or made by a method according to any of the embodiments described herein, in applications requiring a non-flammable material, such as combustible fuel containers, thermal barriers, heat shields, barbecue grill containers, single use barbecue grill containers, energy storage devices, batteries, fuel containers, such as fuel containers for camping stoves, portable stoves or stove burners, or storm kitchens or any other single-use or portable heating and / or cooking equipment, such as that used by relief organizations.

[0040] Definitions

[0041] The term "heat- and / or light-providing arrangement" is intended to mean an arrangement that, when in use, is intended to provide heat, or light, or a combination of both.

[0042] A "light-providing arrangement" may be a candle arrangement which comprises a combustible fuel body in the form of a candle which includes at least one wick, and optionally at least one wick holder, wherein the candle arrangement is intended to provide light as the at least one wick burns (even though heat may also be produced as the at least one wick burns). A "heat-providing arrangement" may be a cooking or heating arrangement, such as a camping stove, a single-use or portable heater, or a storm kitchen, wherein the combustible fuel body is intended to provide heat as it burns (even though light may also be produced as the combustible fuel body burns.

[0043] The term "combustible fuel container" is intended to mean a two- or three-dimensional object of any size and shape in which at least part of the combustible fuel body may be contained, i.e., held, supported, or placed. A combustible fuel container may be configured to contain at least part of a single combustible fuel body, or to contain at least part of a plurality of combustible fuel bodies.

[0044] The term "combustible fuel body" is intended to mean any solid, liquid or gel-like fuel that is intended to provide heat, or light, or a combination of both as it burns. A combustible fuel body may comprise at least one ignitable wick is embedded or immersed therein, whereby the at least one wick may be lit so that the combustible fuel body produces light as it burns, such as a candle. Alternatively, the term "combustible fuel body" is intended to mean combustible fuel that is used for an application that does not require the production of light, whereby no wick is required but where the combustible fuel body is lit to produce heat as it burns.

[0045] A combustible fuel body may comprise or consist of wax, paraffin wax, liquid paraffin, beeswax, rapeseed wax, palm wax, coconut wax, soy wax, tallow, vegetable oil, olive oil, or any other solid, liquid or gel-like fuel, such as a solid fuel tablet, such as an ethanol-based gel.

[0046] The terms "not flammable" and "non-flammable" are intended to mean that combustion cannot be initiated by the introduction of an ignition source such as a flame, spark, or heat.

[0047] The term "density" is intended to mean mass divided by volume and all density values cited herein refer to the density determined at a temperature of 25°C and under standard atmospheric pressure (101.352 kPa). A combustible fuel container according to the present invention need not necessarily have a constant density throughout its volume but must have a density equal to or greater than the "minimum density" in all parts of its volume.

[0048] The term "coating" is intended to mean a continuous or non-continuous layer or film applied to at least part of a surface, such as a surface of cellulose fibres, a surface of a dry blank of cellulose fibres, or a surface a combustible fuel container. One or more coatings may be applied to a combustible fuel container during and / or after its production by dry moulding. Additionally, or alternatively one or more coatings may be applied to cellulose fibres or cellulose fibre-containing material before a dry blank of cellulose fibres is produced.

[0049] The term "fire-retardant" is intended to mean a chemical compound or composition that prevents fire. The expression fire-retardant may be used interchangeably with flame retardant.

[0050] The term "combustible fuel body-material-penetration preventer" is a chemical compound or composition that reduces the risk for combustible fuel body material, such as molten wax, to penetrate the combustible fuel container. The combustible fuel body-material-penetration preventer may be a grease penetration preventer, an oil barrier coating, or the like.

[0051] The term "providing a dry blank of cellulose fibres" is intended to mean supplying or producing one or more layers of a web of cellulose fibres of any suitable shape and size. A dry blank of cellulose fibres may be produced by air forming for example. The dry blank of cellulose fibres is intended to be further shaped or finished to produce a combustible fuel container.

[0052] The word "dry" is intended to mean having a moisture content of 0-25% by weight thereof, preferably a moisture content of 0-5 %, 0-10%, 5-10%, 0-20%, 5-20%, 10- 20%, or 15-25%. For example, a liquid binder may be used to bind cellulose fibres together as long as the dry blank of cellulose fibres produced from therefrom has a maximum moisture content of 5%, 10%, 15%, 20% or 25%.

[0053] The terms "dry-formed" and "dry moulded" refer to products created using a dryforming technique which starts with dry cellulose fibres, i.e. cellulose fibres having a moisture content as described in the previous paragraph. The dry-forming technique may involve air-laying cellulose fibres into a dry web and forming products using heat and / or pressure, or combining air-laid formation and fast pressing. It can also include processes such as stamping, draping, forming, pressing and releasing materials using multi-step tools, where cellulose fibres are sintered together in a dry state.

[0054] The terms "dry-formed" and "dry moulded" also refer to products created using a wetforming technique which starts with wet cellulose fibres, i.e. cellulose fibres having a moisture content greater than 25%, such as a slurry of cellulose fibres suspended in a liquid, such as water, whereby the wet cellulose fibres or pulp is / are subsequently dried at a later stage in the manufacturing process. The wet-forming technique may involve wet-laying cellulose fibres into a wet web, then drying and forming products using heat and / or pressure. It can also include processes such as in-mould curing, stamping, draping, forming, pressing and releasing materials using multi-step tools, where cellulose fibres are sintered together in a wet state and then dried.

[0055] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0056] All embodiments of the invention and particular features mentioned herein may be taken in isolation or in combination with any other embodiments and / or particular features mentioned herein (hence describing more particular embodiments and particular features as disclosed herein) without departing from the disclosure of the invention.

[0057] As used herein, the term "comprises" will take its usual meaning in the art, namely indicating that the component includes but is not limited to the relevant feature(s) (i.e. including, among other things). As such, the term "comprises" will include references to the component consisting essentially of the relevant feature(s).

[0058] As used herein, unless otherwise specified the terms "consists essentially of" and "consisting essentially of" will refer to the relevant component being formed of at least 80% (e.g. at least 85%, at least 90%, or at least 95%, at least 99%, or 100% of the specified substance(s), according to the relevant measure (e.g. by weight thereof). The terms "consists essentially of" and "consisting essentially of" may be replaced with "consists of" and "consisting of", respectively.

[0059] For the avoidance of doubt, the term "comprises" will also include references to the component "consisting essentially of" (and in particular "consisting of") the relevant substance(s).

[0060] Brief description of the drawings

[0061] Figures 1 and 2 illustrate examples of a heat- and / or light-providing arrangement according to embodiments of the present invention. Figure 3 schematically illustrates a test method, as described herein, where an ignition source flame is applied so that the mid-point of the flame maintains contact with an open top edge of a combustible fuel container according to the present invention.

[0062] Figure 4 illustrates the performance of a test in accordance with the standard ASTM F2417-17 as described herein.

[0063] Figures 5 & 6 schematically show steps in the production of a combustible fuel container according to an embodiment of the present invention.

[0064] Figure 7 is a flow chart showing steps of a method according to an embodiment of the invention.

[0065] Description

[0066] Figure 1 is a cross-sectional view of a heat- and / or light-providing arrangement 10 comprising a combustible fuel container 12 containing a combustible fuel body 14.

[0067] A combustible fuel body 12 may include one or more ignitable wicks 16 comprising any material known for wicks as used in the art. For example, a wick 16 may comprise or consist of cellulose-containing material, such as one or more of the following: wood, paper, cotton such as braided cotton, zinc or tin, or any combination thereof. A wick 16 may have a paper core or a zinc core.

[0068] The combustible fuel container 12 may further comprise a wick holder (not shown in Figure 1) to hold at the one or more ignitable wicks 16 in place, such as a wick holder attached to the base 12b of the combustible fuel container 12. The wick holder may comprise or consist of the same material as the combustible fuel container 12. For example, the wick holder may comprise fibrous cellulose and optionally, a flame retardant, such as vermiculite.

[0069] Alternatively, a heat- and / or light-providing arrangement 10 may comprise a combustible fuel container 12 containing a combustible fuel body 14 without a wick, wherein the fuel body is arranged to be ignited by exposing it to an ignition source such as a flame. The combustible fuel container 12 comprises or consists of dry moulded cellulose fibres and has a minimum density of 250 kgnr3. Such a combustible fuel container 12 will contain the molten combustible fuel as the combustible fuel body 14 burns without catching fire and will thereby provide a heat- and / or light-providing arrangement 10 whose combustible fuel body 14 will burn in a safe and controlled manner.

[0070] Advantageously, the combustible fuel body 14 may be fossil free and / or renewable. For example, the combustible fuel body material may comprise or consist of beeswax, rapeseed wax, palm wax or coconut wax. Optionally, the combustible fuel body 14 may comprise a scent.

[0071] Optionally, a heat- and / or light-providing arrangement 10 or the combustible fuel container 12 may comprise a set of feet 18. Feet 18 may protrude from a base 12b of a combustible fuel container 12, as shown in Figure 1 for example, and are optionally integrally formed with the combustible fuel container 12.

[0072] The combustible fuel container 12 may comprise a base 12b and at least one side 12s. A base 12b and sides 12s of a combustible fuel container 12 need not necessarily have the same thickness. In the illustrated embodiment, the base 12b extends in a base plane and a side 12s extends from the periphery of the base 12b in a direction substantially perpendicular to the base plane. The outer surface of the combustible fuel body 14 is in contact with the inner surfaces of the base 12b and side 12s of the combustible fuel container 12.

[0073] In the embodiment illustrated in Figure 1 an entire combustible fuel body 14 is contained within the combustible fuel container 12 and the top surface of the combustible fuel body 14 lies flush with an open top edge 12e of the combustible fuel container 12.

[0074] A heat- and / or light-providing arrangement 10 according to the present invention may comprise at least one relatively short squat combustible fuel body 14, i.e., a combustible fuel body 14 having a maximum height and a maximum width, wherein the maximum height of the combustible fuel body 14 is less than, or equal to the maximum width of the combustible fuel body 14. The combustible fuel body 14 may have a maximum height of 15 cm, or a maximum height of 10 cm, or a maximum height of 5 cm, such as a combustible fuel body having a height of 1-10 cm, or 2-10cm, or 3-10 cm, or 4-10 cm or 5-10 cm, or 1-5 cm, or 2-5 cm. The heat- and / or light-providing arrangement 10 may be of any size and shape, such as a tealight or filled candle having a size suitable for being placed on a table such as a dining table or a coffee table. For example, the heat- and / or light-providing arrangement 10 may have a size and shape as known in the art, such as a cylindrical shape, a diameter of from about 30 to about 60 millimeters, such as from about 30 millimeters to about 50 millimeters, such as from about 30 millimeters to about 40 millimeters, such as about 38 millimeters and / or a height from about 10 millimeters to about 25 millimeters such as about 16 millimeters.

[0075] In a further example, heat- and / or light-providing arrangement 10 may have a cylindrical shape with a diameter of from about 30 millimeters to about 200 millimeters such as from about 30 millimeters to about 60 millimeters, such as from about 60 millimeters to about 130 millimeters, such as from about 70 millimeters to about 150 millimeters, such as from about 130 millimeters to about 200 millimeters, and / or a height from about 20 millimeters to about 200 millimeters such as about 80 millimeters.

[0076] Alternatively, or additionally, a heat- and / or light-providing arrangement 10 may be configured to comprise at least one tall and thin combustible fuel body, such as a candle, i.e., a combustible fuel body 14 having a maximum height that is greater than its maximum width. The maximum height of such a combustible fuel body 14 may be more than 15 cm. A heat- and / or light-providing arrangement 10 according to the present invention may be configured to comprise both at least one short and squat combustible fuel body, and at least one tall and thin combustible fuel body.

[0077] The combustible fuel container 12 may further comprises at least one additive, such as a fire-retardant additive. A fire-retardant additive, and optionally a combustible fuel body penetration preventer additive may be mixed, or homogeneously mixed, with cellulose fibres during the production of the combustible fuel container 12 prior to and / or after pressing.

[0078] Alternatively, or additionally, a fire-retardant and optionally a combustible fuel body penetration preventer may be provided as one or more coatings 20 on part or all of one or more surfaces of a dry blank of cellulose fibres during the production of the combustible fuel container 12. Alternatively, or additionally, a fire-retardant and / or a combustible fuel body penetration preventer may be provided as one or more coatings 20 on at least part of at least one surface of a dry moulded combustible fuel container A fire-retardant additive or coating may comprise one or more of the following: mineral(s), organohalogen compound(s), organophosphorous compound(s), salt(s) of inorganic compound(s), antimony containing compounds, silicate(s).

[0079] Examples of mineral fire-retardant additives or coatings include, but are not limited to, one or more of the following: aluminium hydroxide such as aluminium trihydroxide (ATH), magnesium hydroxide (MDH), metal borate such as zinc borate, metal stannates such as zinc hydroxystannate, inorganic filler(s) such as talcum or chalk (i.e. calcium carbonate), huntite, hydromagnesite, hydrous phyllosilicate mineral such as vermiculite such as exfoliated vermiculite. In an example, the mineral fire-retardant may comprise or consist of vermiculite such as exfoliated vermiculite.

[0080] Examples of organohalogen compound-based fire-retardant additives or coatings include, but are not limited to, one or more of the following: organochlorines such as chlorendic acid and / or chlorinated paraffins, organobromines such as decabromodiphenyl ether, decabromodiphenyl ethane, polymeric brominated compounds such as brominated polystyrenes, brominated carbonate oligomers, brominated epoxy oligomers, tetrabromophtalic anhydride, tetrabromobisphenol A, hexabromocyclododecane. These fire-retardants may be used in conjunction with a synergist to enhance their efficiency. For example, antimony-based synergists may be used.

[0081] Examples of organophosphorous compound-based fire-retardant additives or coatings include, but are not limited to, one or more of the following: organophosphates such as triphenyl phosphates (TPP), resorcinol bis(diphenylphosphate) (RDP), bisphenol A diphenyl phosphate (BADP), tricresyl phosphate (TCP), phosphonates such as dimethyl methylphophonate (DMMP), phosphinates such as aluminium diethyl phosphinate. These fire-retardants additives or coatings may comprise both phosphorous and a halogen such as tris(2,3-dibromopropyl)phosphate(brominated tris) and chlorinated organophosphates such as tris(l,3-dichloro-2-propyl)phosphate (chlorinated tris or TDCPP) or tetrakis(2-chloroethyl)dichloroisopentyldiphosphate.

[0082] An example of an antimony containing fire-retardant additive or coating includes antimony trioxide.

[0083] An example of a silicate fire-retardant additive or coating includes alkali containing silicates such as sodium silicate. In an example, the fire-retardant additive or coating may comprise or consist of one or more of the following: guanidine sulfamate, vermiculite, hydroxyapatite, aluminium trihydroxide, clay. In still an example, the fire-retardant may comprise or consist of vermiculite. The vermiculite, which is a hydrous phyllosilicate mineral, may be exfoliated. Further, the vermiculite may be provided as a powder or a suspension such as aqueous suspension which may be added to the fibrous cellulose described herein. Thus, there is provided the use of vermiculite for preparing a combustible fuel container comprising fibrous cellulose, such as a tealight combustible fuel container.

[0084] The combustible fuel container 12 may comprise from about 5 wt% to about 90 wt% of the fire-retardant additive or coating based on the total weight of the combustible fuel container 12. For example, the combustible fuel container 12 may comprise from about 20 wt% to about 90 wt%, such as from about 30 wt% to about 60 wt%, such as from about 40 wt% to about 55 wt% of the fire-retardant additive or coating based on the total weight of the combustible fuel container 12. In still a further example, the combustible fuel container 12 may comprise about 50 wt% of the fire-retardant additive or coating based on the total weight of the combustible fuel container 12.

[0085] Figure 2 shows a combustible fuel container 12 according to an embodiment of the invention which comprises such a coating 20 on its entire inner surface 12i. The combustible fuel container 12 comprises an opening 22 delimited by an open top edge 12e, which is configured to receive at least part of a combustible fuel body 14. In the illustrated embodiment, the entire inner surface 12i of the combustible fuel container 12 that faces and / or contacts a combustible fuel body material when at least part of a combustible fuel body 14 has been placed or supported or inserted into the combustible fuel container 12 comprises a coating 20.

[0086] Additionally, or alternatively, a combustible fuel container 12 may comprise at least one coating 20 on at least part of an outer surface 12o thereof. Additionally, or alternatively, one or more coatings may be provided on the upper open edge 12e of a combustible fuel container 12.

[0087] The fire-retardant additives and / or coatings 20 described herein may be miscible with the fibrous cellulose of the combustible fuel container 12. Further, the fire-retardant additives and / or coatings 20 may be regular fire-retardant additives or coatings, eco- friendly fire-retardant additives or coatings, or a mixture thereof. For example, the combustible fuel container 12 of the heat- and / or light-providing arrangement 10 may be configured to be recyclable in a paper recycling process or disposable in household waste, composts or even landfills where its materials may decompose into natural elements. For example, the cellulose of the combustible fuel container 12 may be biodegraded by microorganisms while any fire-retardant additive or coating 20 may be a rest product that may reused or disposed of. Advantageously, combustible fuel containers 12 as described herein comprising vermiculite may be processed in a compost and subsequently used as a soil conditioner. Further, it is envisaged that the cellulose and any fire-retardant, such as vermiculite, of a combustible fuel container 12 may be separated from each other so that the combustible fuel container 12 may be recycled as paper.

[0088] It will be appreciated that the combustible fuel container 12 may further comprise a dye or a pigment allowing the combustible fuel container to have a desired colour. For instance, the dye or pigment may be present in a coating 20 added to the combustible fuel container 12. Advantageously, the dye or pigment is miscible with the fibrous cellulose of the combustible fuel container 12and optionally the fire-retardant and / or the combustible fuel body penetration preventer-additive or coating, such as a wax penetration preventer-additive or coating.

[0089] Flame retardancy tests according to the Standard Specification for fire Safety for Candles ASTM F2417-17 (which refers to plastic containers) were carried out to check the fire resistance of combustible fuel containers according to the present invention.

[0090] The test requirements according to ASTM F2417-17 are as follows:

[0091] 4.6.2.1 The total burn time for the ten containers shall be less than or equal to 300 s.

[0092] 4.6.2.2 No single burn time of a container shall exceed 30 s.

[0093] 4.6.2.3. No single container shall be completely consumed during testing.

[0094] The test procedure according to ASTM F2417-17 is as follows:

[0095] 5.4.3.4 Apply the ignition source flame so that the mid-point of the flame maintains contact with the open top edge of the container for 10 s.

[0096] 5.4.3.5 Maintain flame contact in a straight line at the 12 o 'clock position of the test specimen by moving the ignition source as the wall deforms, shrinks, burns, or melts away.

[0097] 5.4.3.6 Remove the ignition source from the container after 10 s.

[0098] 5.4.3.7 Measure and record any burn time after the ignition source is removed. 5.4.3.8 Reapply the ignition source flame as described in 5.4.3.4 - 5.4.3.7 5 s after the flame extinguishes.

[0099] 5.4.3.9 Remove the ignition source after 10 s exposure.

[0100] 5.4.3.10 Measure and record any burn time after the ignition source is removed this second time.

[0101] 5.4.3.11 Clean the test surface after testing each specimen to avoid charred material from a previous test interfering with a subsequent test.

[0102] 5.4.3.12 Repeat this procedure nine more times until a total of ten specimens have been tested.

[0103] 5.4.3.13 Find the total burn time by adding the burn times after each of 10 s exposure for all ten containers tested (20 total burn times).

[0104] Figure 3 illustrates item 5.4.3.4 in the test method in which the mid-point 24 of a flame 26 maintains contact with the open top edge 12e of a combustible fuel container 12 for ten seconds.

[0105] Figure 4 illustrates the performance of a test in accordance with the standard ASTM F2417-17 as described herein.

[0106] The results of these tests showed that the combustible fuel containers according to the present invention are suitable for use in the applications described herein since the burn time was found to be five seconds or less, i.e., from 0 seconds to 5 seconds.

[0107] An extreme test was also carried out to simulate a situation that can occur when combustible fuel bodies in combustible fuel containers are used by consumers. In the extreme test, the combustible fuel body was lit with a match and the match was left in the burning container. Thereafter, it was observed if the combustible fuel container caught fire, and if so, how many seconds it took until the combustible fuel container caught fire. Each test was performed twice.

[0108] This extreme test is important because the match can transport melted combustible fuel body material, such as wax, to the edge of the combustible fuel container and create a flame directly on the combustible fuel container. The combustible fuel containers made from materials like aluminium, glass, ceramics, or some plastics will not tend to take up combustible fuel body material in the combustible fuel container itself, but there is a risk of this when working with materials comprising cellulose fibres. If the combustible fuel container itself absorbs combustible fuel body material, there is a risk that the combustible fuel container will act as a wick transporting the burning combustible fuel body material, thereby making the combustible fuel container unsafe for use. Therefore, this test was performed in addition to the test according to ASTM F2417-17.

[0109] The result of this extreme test was that the burn time of the combustible fuel container was 10 seconds or less.

[0110] The combustible fuel container material described herein is therefore suitable for use in any application requiring a non-flammable material.

[0111] Figures 5 and 6 schematically show an example of a forming tool 28 that may be used in a method according to the present invention.

[0112] In the illustrated embodiment the forming tool 28 comprises a first male member 30 and a female member 32, which are configured for interacting with each other for forming a dry moulded combustible fuel container 12 from a dry blank of cellulose fibres 34.

[0113] In the method according to the present invention a dry blank of cellulose fibres 34 may be provided in any suitable two- or three-dimensional shape. A dry blank of cellulose fibres 34 may also be provided in any suitable size, wherein a single dry blank of cellulose fibres 34 may be used to produce a single dry moulded combustible fuel container 12 or a plurality of dry moulded combustible fuel containers 12.

[0114] Alternatively, a plurality of dry blanks of cellulose fibres 34 with the same or different properties may be used to produce a single dry moulded combustible fuel container 12. For example, at least one dry blank of cellulose fibres 34 having flame retardant properties may be combined with at least one dry blank of cellulose fibres 34 not having flame retardant properties to produce a single dry moulded combustible fuel container 12.

[0115] In the illustrated embodiment, a dry blank of cellulose fibres 34 is provided in the form of a continuous or non-continuous sheet that may be intermittently fed towards a forming tool 28 in the direction indicated by the arrow 31. Alternatively, a dry blank of cellulose fibres 34 may be provided as a two-dimensional structure, such as a disc, three-dimensional structure, such as a capsule that is placed inside the forming tool 28.

[0116] The first male member 30 and the female member 32 are movably arranged relative to each other in a pressing direction, P. A forming surface 30f of the first male member 30 is configured to form an inner surface 12i of a combustible fuel container 12. A forming surface 32f of the female member 30 is configured to form an outer surface 12o of a combustible fuel container 12 when the dry blank of cellulose fibres 34 is brought into contact with the forming surface 30f, 32f of the forming tool 28.

[0117] In the illustrated embodiment, the method comprises vertically displacing the first male member 30 relative to the female member 32 in the pressing direction, P, and pressing against the dry blank of cellulose fibres 34 with a pressure of at least 1 MPa, such as a pressure of 1-100 MPa or higher.

[0118] Optionally, the method comprises heating the dry blank of cellulose fibres 34 to a temperature of at least 100°C before the pressing and / or during the pressing. Any suitable heating means may be used, such as an electric heating element, such as a resistor element, or a fluid heater.

[0119] The pressing may be carried out in a single pressing operation or in a plurality of pressing operations so that a combustible fuel container 12 comprising dry moulded cellulose fibres and having a minimum density of 250 kgm-3is produced.

[0120] The forming tool 28 may be hydraulically, pneumatically, or electrically operated. A forming tool 28 preferably comprises a plurality of forming surfaces 30f, 32f, which may be brought into contact with one or more dry blanks of cellulose fibres 34. A plurality of combustible fuel containers 12 may thereby be formed from the same dry blank of cellulose fibres 34 and then cut to form individual combustible fuel containers 12. Alternatively, a plurality of individual combustible fuel containers 12 may be formed from a plurality of dry blanks of cellulose fibres 34 simultaneously.

[0121] Optionally, a forming tool 28 may comprise a second male member (not shown) that is movably arranged with respect to the first male member 30 and the female member 32, such as a ring-shaped second male member located around the outer periphery of the fist male member 30. The method comprises further compressing the dry moulded cellulose fibre material (as indicated by the arrows 36) while the dry moulded cellulose fibre material is in contact with the forming surface 30f, 32f of the forming tool 28 to further increase the density of at least part of the dry moulded combustible fuel container 12 and / or to provide the dry moulded combustible fuel container 12 with an even open top edge 12e. Alternatively, or additionally, the density of a combustible fuel container 12 may be increased by calendering the dry blank of cellulose fibres 34 prior to pressing.

[0122] After pressing, the method may comprise the step of moving the first male member 30 and any second male member, away from the female member 32 of the forming tool 28 to allow the dry moulded combustible fuel container 12 to be further treated or removed from the forming tool. Another dry blank of cellulose fibres 34 can then be brought into contact with the forming surface 30f, 32f of the forming tool 28 and the process may be repeated.

[0123] The method may comprise cutting the dry moulded combustible fuel container 12 to a desired shape and size while it is in the forming tool 28 or after it has been removed from the forming tool 28. Alternatively, or additionally the method may comprise cutting the dry blank of cellulose fibres prior to pressing, whereby a pre-cut dry blank of cellulose fibres is pressed into the desired shape.

[0124] The method optionally comprises feeding any excess cellulose-containing material, such as material cut from the dry moulded combustible fuel container 12, back into the process, via the shredding or milling apparatus for example, to recycle any waste products. The material may for example be returned for shredding and / or milling to provide cellulose fibres for use in a subsequent combustible fuel container-making process, optionally as a complement to "virgin cellulose-containing material(s)" that is / are fed to a shredding and / or milling apparatus.

[0125] The method may comprise using a forming tool 28, including a forming surface 30f, 32f, such as a spring-loaded forming surface 30f, 32f comprising a compressible or deformable material, such as an elastomer, which allows a forming surface 30f, 32f to be re-shaped during compression / deformation. Such a compressible or deformable forming surface 30f, 32f may be used to apply an isostatic pressure of at least 1 MPa, or 4-10 MPa, or 10-15 MPa, or 10-20 MPa, or at least 20 MPa or 1-100 MPa or higher.

[0126] Such a compressible or deformable material allows pressure to be increased at the sides of the combustible fuel container 12. A combustible fuel container 12 with small release angles is challenging to manufacture as it may be difficult to apply a sufficient pressure on the sides of the combustible fuel container 12 during its production. A sufficient pressure on the sides of the combustible fuel container 12 may be achieved using a forming surface 30f, 32f, comprising a compressible or deformable material, and / or by using a forming tool 28 that comprises a mechanical movement function or the like, as used in the manufacture of plastic and aluminum components.

[0127] A combustible fuel container 12 of a heat- and / or light-providing arrangement 10 according to the present invention is preferably produced as a single piece. A combustible fuel container 12 of a heat- and / or light-providing arrangement 10 according to the present invention may however be produced in a plurality of pieces which are subsequently joined together in any suitable manner.

[0128] Figure 7 is a flow chart that shows essential steps and optional steps (whereby the optional steps are shown with dashed lines) of a method for producing a heat- and / or light-providing arrangement according to the present invention.

[0129] The method comprises producing a combustible fuel container 12 by providing cellulose fibres. The cellulose fibres may be provided by shredding and / or milling cellulose- containing material, such as one or more of the following: bagasse, straw, paper, cardboard, wood and materials of plant cellulose fibres such hemp, linen, cotton, giant reed, eucalyptus tree or miscanthus, and optionally re-cycled dry-formed cellulose- containing material. Shredding may be used to roughly grind the cellulose-containing material and remove impurities therefrom. Milling, in a hammer mill for example, grinds the cellulose-containing material more finely and defibrates the cellulose- containing material.

[0130] One or more additives or coatings may be added to the cellulose fibres during or after the milling process. Optionally, the one or more additives, such as one or more binders, or coatings are homogeneously mixed with the cellulose fibres. The cellulose fibres may be transported through a pipe system using air so that a dry blank of cellulose fibres can be produced.

[0131] The method comprising providing a continuous or non-continuous dry blank of cellulose fibres 34 of any suitable shape or size, by air forming for example, such as by allowing the cellulose fibres to fall on a transport means, such as a conveyor belt. The method comprises bringing the dry blank of cellulose fibres 34 into contact with a forming surface 30f, 32f of a forming tool 28.

[0132] A dry blank of cellulose fibres 34 may be provided inside the forming tool 28 by feeding cellulose fibres into a forming tool 28 and directing the cellulose fibres toward a forming surface 30f, 32f using a transporting means, such as a system of pipes, a conveyor belt or an industrial robot. A negative pressure vacuum may be created inside the forming tool 28 using any conventional means in order to bring the cellulose fibres into contact with the forming surface 30f, 32f.

[0133] The method comprises pressing the forming surface 30f, 32f of the forming tool 28 against the dry blank of cellulose fibres 34 with a pressure of at least 1 MPa, such as 1-100 MPa or higher, thereby producing a combustible fuel container 12 comprising dry moulded cellulose fibres and having a minimum density of 250 kgm-3. The dry blank of cellulose fibres 34 may be heated to a temperature of at least 100°C before it is pressed and / or during the pressing. The method may comprise heating the forming surface of 330f, 32f of the forming tool 28 to heat the combustible fuel container 12 to a temperature of at least 100°C during pressing.

[0134] At least one surface of the dry moulded combustible fuel container 12 may be coated after the pressing. A coating 20 may additionally or alternatively be applied to a dry blank of cellulose fibres 34 prior to pressing.

[0135] After pressing, the dry moulded combustible fuel container 12 may be removed from the forming tool 28 using any suitable removal device and replaced with a dry blank of cellulose fibres 34.

[0136] The method also comprises placing at least part of a combustible fuel body 14 in the dry moulded combustible fuel container 12.

[0137] Example

[0138] A fluff pulp was milled in a hammer mill to defibrate the cellulose fibres. The cellulose fibres were air-laid to provide a dry blank of cellulose fibres. The dry blank of cellulose fibres was transported to a hydraulic press unit with a forming tool heated to a temperature of at least 150°C and configured to form a candle container for a tealight having a diameter of 40 mm. A pressure of 30-40 MPa was applied during the pressing operation. The candle container was cut to the desired shape during the pressing operation and subsequently coated with vermiculite dispersion DM335 from Dupree Minerals Ltd.

[0139] The candle container was fire tested according to the ASTM F2417-17 standard and it passed the fire test. It was filled with liquid candle wax, provided with a wick, and left at room temperature for 24 hours to allow the candle wax to solidify. During the fire test, the candle container did not ignite and burn with a self-sustaining flame, and the shape of the candle container did not change.

[0140] The candle container was also subjected to an oil test in which mineral oil at room temperature was left in the candle container for at least 12 hours. Cross-sections of the candle container were subsequently analyzed using an image processing program where an indicator in the mineral oil showed whether the mineral oil was present in the cross-sections. No leakage of mineral oil into the candle container was observed. A burn test was conducted in which a complete candle was burned under normal conditions. The candle container did not self-ignite, and candle wax did not leak through the candle container during the burn time.

[0141] It was thereby found that the candle arrangement worked well as a tealight.

Claims

CLAIMS1. A heat- and / or light-providing arrangement (10) comprising a combustible fuel body (14) and a combustible fuel container (12) in which at least part of the combustible fuel body (14) is contained, wherein the combustible fuel container (12) comprises or consists of dry moulded cellulose fibres and has a minimum density of 250 kgnr3.

2. A heat- and / or light-providing arrangement (10) according to claim 1, wherein the combustible fuel container (12) further comprises at least one additive, such as a fire-retardant additive and / or a combustible fuel body (14) materialpenetration-preventing additive.

3. A heat- and / or light-providing arrangement (10) according to any one of the preceding claims, wherein at least one part of the combustible fuel container (12) comprises at least one coating (20), such as a fire-retardant coating (20), and / or a combustible fuel body (14) material-penetration- preventing coating (20).

4. A heat- and / or light-providing arrangement (10) according to claim 1, wherein the combustible fuel container (12) is free of an additive, such as free of a fire- retardant additive and / or free of a combustible fuel body (14) materialpenetration-preventing additive.

5. A heat- and / or light-providing arrangement (10) according to claim 1 or claim 4, wherein at least one surface of the combustible fuel container (12) is free of a coating, such as free of a fire-retardant coating and / or free of a combustible fuel body (14) material-penetration-preventing coating.

6. A heat- and / or light-providing arrangement (10) according to any one of the preceding claims, wherein the combustible fuel body (14) is a solid combustible fuel body (14), and the combustible fuel container (12) is arranged to contain at least part of the solid combustible fuel body (14).

7. The heat- and / or light-providing arrangement (10) according to any one of the preceding claims, wherein at least one of the following has a surface that faces or contacts the combustible fuel body (14) material: the combustible fuel container (12); the at least one coating (20).

8. The heat- and / or light-providing arrangement (10) according to any one of the preceding claims, wherein the heat- and / or light-providing arrangement (10) comprises a combustible fuel body (14) having a maximum height and a maximum width, whereby the maximum height of the combustible fuel body (14) is less than or equal to the maximum width of the combustible fuel body (14).

9. The heat- and / or light-providing arrangement (10) according to any one of the preceding claims, wherein the combustible fuel body (14) comprises at least one wick (16).

10. A method for producing a heat- and / or light-providing arrangement (10) comprising:- producing a combustible fuel container (12) by providing a dry blank of cellulose fibres (34), bringing the dry blank of cellulose fibres (34) into contact with a forming surface (30f, 32f) of a forming tool (28), pressing the forming surface (30f, 32f) of the forming tool (28) against the dry blank of cellulose fibres (34) with a pressure of at least 1 MPa, thereby producing a combustible fuel container (12) comprising dry moulded cellulose fibres and having a minimum density of 250 kgm-3; and heating the dry blank of cellulose fibres (34) to a temperature of at least 100°C before and / or during the pressing, and- placing at least part of a combustible fuel body (14) in the combustible fuel container (12).

11. The method according to claim 10, wherein the method also comprises one or more of the following :- heating the dry blank of cellulose fibres (34) to a temperature of 100-300 °C,- calendering the dry blank of cellulose fibres (34) prior to pressing.- applying a pressure of 1-100 MPa,- applying an isostatic pressure of at least 1 MPa,- providing cellulose fibres by milling cellulose-containing material, and optionally shredding the cellulose-containing material prior to milling,- adding at least one additive, such as a fire-retardant additive to the cellulose fibres, optionally homogeneously mixing the cellulose fibres with at least one additive,- coating at least part of a surface of the dry blank with at least one coating (20), such as a fire-retardant coating and / or a material-penetration preventer coating,- cutting the dry blank of cellulose fibres (34) prior to pressing,- cutting the dry moulded combustible fuel container (12) while it is in the forming tool (28) and / or after it has been removed from the forming tool (28),- cutting the dry moulded combustible fuel container (12) after pressing,- feeding any excess cellulose-containing material back into the process to recycle any waste products,- using a forming tool (28) comprising a compressible or deformable material that allows the forming surface (30f, 32f) to be re-shaped during compression / deformation.

12. Use of material comprising or consisting of dry moulded cellulose fibres and having a minimum density of 250 kgm-3in applications requiring a nonflammable material.

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