NL2007938C2 - Image forming technique. - Google Patents

Description

Image forming technique DESCRIPTION

FIELD OF THE INVENTION

5 The present invention is in the field of image forming on a liquid.

BACKGROUND OF THE INVENTION

Printing is a process for reproducing text and image, typically with ink on paper using a printing press. It 10 is often carried out as a large-scale industrial process, and is an essential part of publishing and transaction printing. Printing is performed on a solid substrate, such as to secure adherence of a print to the substrate.

In a paper by GF Schneider et al, "Wedging transfer 15 of nanostructures", Nano Letters 2010, 10, 1912-1916, is reported on a so-called 'transfer printing method' permitting a transfer of nanostructures and graphene on Si02 onto surfaces of various shapes and compositions. The transfer of nanostructures and graphene occurs through intercalation of a 20 layer of water between a hydrophilic substrate and nanostructures and graphene locked within a hydrophobic polymer thin film. As a result, the film entrapping the nanostructure and graphene is lifted off and floats at an air-water interface. The nanostructure can subsequently be 25 deposited onto a target substrate by the removal of the water and the dissolution of the polymeric film.

The method in this publication aims at transferring nanostructures and graphene from one solid surface to another. However, it is not possible to directly write on a 30 liquid, such as water.

However, it is not possible to directly write an image, pattern, drawing, logo, sentence, word, number on a liquid, such as water and water containing liquids.

As mentioned in the article the nanostructures 35 being transferred, are very small (i.e., micrometer sized and nanometer thin, down to a single atom) and are therefore very different in nature from real life structures, e.g. in terms of integrity, mass, handling properties etc. The method is e.g. as a consequence only applicable in laboratory 2 conditions, being well defined, having sophisticated equipment, highly trained personal, etc. The structures transferred can only be read and detected with help of further means, such as a microscope.

5 The above method further requires provision of a further substrate, such as a polymer layer dried from a polymeric solution, to which the nanostructure is adhered. In a further step the polymer is dissolved again. Only at that point the structure is released to the substrate. Such 10 transfer methodology is somewhat complex, especially under non-laboratory conditions.

It is noted that water is used to release the polymer, to which the nanostructure is adhered, towards the combination of a hydrophilic substrate and a hydrophobic 15 polymer. Such methodology provides for a polymer layer comprising a nanostructure, but not the structure itself.

There are various patent publications reciting edible substrates, possibly comprising an image, ink and the like. The substrates are provided to a surface of a solid 20 material or the like, such as an edible article. Typically also a coating is provided in order to support an image. The substrates are typically not applicable to a liquid. The publications however do not provide transfer of an image to (a surface) of a liquid.

25 There are various patent publications reciting toy products, pens and alike. These may be in the field of the present invention, but are very different conceptually and products are different as well. For instance they do not provide for an image to be transferred to a liquid, let alone 30 a stable image. Typically further measures are needed for providing an image, such as a specific support or the like, such as a porous layer, cloth, sheet etc. Often images are not permanent, appear or disappear under changing circumstances etc. As a consequence the images are not suited 35 as e.g. a toy for children within the present context.

Even further publications do not relate to an image that has such integrity that can be transferred by itself, e.g. without a support, carrier or the like.

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Also hydraulic image transfer methods are recited. However, the image is not released into a liquid, i.e. it remains on a film, but rather transferred from one solid surface to another solid surface, thereby applying hydraulic 5 pressure. The other surface may be uneven or curved.

Typically an activator is used for transfer.

Further dip transfer of an image on a film, comprising the image, to a surface of a solid article is recited. Therein water is used to support ink to a surface.

10 The image is further liquefied with a solvent activator. Further the ink cannot enter the water, i.e. cannot be released therein. Solvents and compounds used are typically highly toxic.

Various patent publications relate to transfer of 15 an image to a solid substrate, making use of a film, on which the image is formed first. Transfer may be assisted by activation, by chemicals, by providing radiation, such as heat or light, by curing, etc.

Typically the above publications involve complex 20 steps, make use of complicated processes, use non-readily available chemicals and the like, are aimed at transferring to a solid substrate, are typically used as industrial process, are aimed at providing a lacquer, coating, paint or the like, etc.

25 In view of the above the present invention relates to providing a method for transferring a readable image from a first surface directly to a liquid, that is legible without a need for further means, such as a microscope, images formed, as well as a toy and kit, which overcome one or more 30 of the above disadvantages, without jeopardizing functionality and advantages.

SUMMARY OF THE INVENTION

The present invention relates to a method for 35 making a readable image on a liquid according to claim 1, an adhesive ink for use in the present method, a carrier, a preprint comprising a readable self-supporting image and a support, the image comprising a dried ink according to the invention, a kit, a method of learning, and a playing game.

4 A solution has been found experimentally to transfer e.g. patterns, numbers, letters and images to a surface of or into a liquid. The present invention relates to a simple technique for transfer and does not require advanced 5 skills to handle it, which can be used as a playful element in toys, used as food supplements, used as a learning method, which may include sensory properties, etc. The present invention will, amongst others, excite people. Other applications are envisaged, such as products that can be used 10 to decorate or personalize beverages or other food products.

The image is large enough to be recognized by a human eye without need or help of further means, such as a microscope. If the image comprises alphanumerical characters, these characters are legible.

15 It was so far impossible to actively write or provide a solid-state image on the surface of liquids, water containing liquid, liquid with water like properties, and the like. The present method is specifically applicable to non-foamed liquids, and foamed liquids, such as beer. As a result 20 an image floats on and/or in the liquid. It has to the knowledge of the inventors not been proposed to dynamically write/print (edible) letter, draw/print (edible) images etc. directly on water and water containing liquids.

The present invention in example specifically 25 relates to a technique to transfer just-written thin patterns onto a surface of water and the like and innovative applications of this method such as mentioned in the present application.

The method preferably uses aqueous solutions to 30 transfer e.g. hydrophobic and partly hydrophilic patterns from an e.g. hydrophilic substrate to a water/air interface. The present products relate to ink, pen, printer cartridges, and various hydrophilic substrates ranging from e.g. thin sheets of 'chemically modified' sheets of solid-state 35 materials such as paper, to bulk solid-state materials, plastics, ceramics, metals, semiconductors and silicates.

As such the composition may typically be hydrophobic. Depending on the liquid and substrate one is typically hydrophobic, whereas the other is typically 5 hydrophilic. The composition typically is of adhesive nature, and preferably not bonding or penetrative.

If in an example the chemical composition of the ink is incidentally of bonding nature with the substrate, 5 then typically a release agent will be provided in the composition.

It is noted that objects can float on water due to buoyancy and/or due to surface tension forces. In order to obtain an image that floats in a liquid the density of the 10 (dried) image is in the order of the density of the liquid. Buoyancy and/or surface tension forces allow an object to float. If the surface tension is relatively small, the density of the image is typically smaller than that of the liquid.

15 The present invention also relates to a consumer product in the field of toy and food/beverage products in which one uses a kit for i) writing a hydrophobic pattern on a hydrophilic substrate, 20 ii) slowly dipping a hydrophilic substrate into an aqueous liquid (water in a glass, containers, cocktail, wine, juice, and bath) until the pattern is immersed, iii) when dipping the water is allowed to penetrate the hydrophilic/hydrophobic interface to release the pattern 25 that will subsequently float on or in the aqueous liquid.

It is noted that the substrate and the liquid may be hydrophilic to a certain extent and may be hydrophobic to a certain extent. Typically one is more hydrophilic. The extent can be tailored to requirements, e.g. by adding or 30 removing certain polymers, changing a composition of the ink likewise, changing properties of the substrate (surface), etc.

In an aspect the invention relates to a substrate having a suitable roughness, surface chemistry, such as 35 determined by the contact angle, that is chemically compatible with the release agent present in the composition, such as ink, making the dry ink not sticking to the substrate, and allows release of the image to be formed thereon.

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The surface of the substrate is preferably impermeable and/or non-reactive so as.not to permanently receive the composition, e.g. ink image, in order to secure that the image formed can be wedged by the liquid. The 5 substrate can be selected from: glass, metals, chemically modified paper and plastic sheets, such that e.g. the ink does not permanently stick to the substrate, possibly in combination with a release agent; ceramics, polymers such as melamine resin, poly ethylene, poly propylene, poly 10 vinylchloride, polymeric tetrafluoroethylene, poly vinylidene, hydrophilic melamine resin, hydrophilic poly ethylene, hydrophilic polypropylene, hydrophilic poly vinylchloride, hydrophilic polymeric tetrafluoroethylene, hydrophilic polyvinylidene, oxidized poly ethylene, oxidized 15 polypropylene, oxidized poly vinylchloride, oxidized polymeric tetrafluoroethylene, oxidized poly vinylidene, more generally a hydrophilic polymer, borosilicate, quartz, silica and silicon, and silicon oxide. The materials include solid state materials, surface modified solid-state materials, 20 metals, semiconductors, (boro)silicate-containing and plastics (by means of polycations and polyanions such as polyallylamine, polystyrene sulfonate, poly(diallyldimethylammoium chloride), polyacrylic acid, chitosan, hyaluronic acid, polyelectrolytes, ionomers, non-25 charged polymers, silanes, thiols, biopolymers such as DNA or proteins, albumin, poly-sugars, polysaccharides, polypeptides, polynucleotides, alginates, including any suitable pigment to color the substrate (dyes, nanomaterials, composites, phtalocyanine green, Ti02, chrome green, carbon 30 black, chrome yellow, and mixtures), and combinations thereof.

It has been found that the non-dried composition has a contact angle with the substrate of less than 80° and of more than 5°, such as less than 70° and of more than 10°, 35 typically between 20° and 60°. As such good results are obtained, e.g. in terms of integrity of the image.

In this process, a liquid such as water acts as a wedge between image and substrate, permitting to transfer instantaneously (a few seconds), by progressively lifting, 7 any image of considerable size onto the surface thereof. It has been found that a contact angle of the liquid on the dried image of more than 5°, preferably an angle of more than 20°, such as more than 90°, provides good results, e.g. in 5 terms of dried composition being released easy from the substrate, the image remaining intact and self-supporting. It is noted that depending on an application this contact angle may be larger or smaller. For instance a larger contact angle, such as more than 90°, provides a good solubility, 10 whereas a smaller contact angle, such as less than 20°, provides a good stability. In view of wedging characteristics, this contact angle is preferably large, such as more than 90°.

The contact angle is the angle at which a 15 liquid/vapor interface meets a solid surface.

Further, in order to improve release the image from the support, the surface of the substrate is preferably substantially smooth, and further cannot be penetrated by the liquid and/or ink.

20 Typically the image is formed at ambient

temperature, i.e. from about 0 °C - 40 °C, such as 25 °C. Further typically a relative humidity is from 40-80%. It is however also envisaged to transfer images to hot beverages, having a temperature of more than 60 °C, such as from 80 °C

25 to about 100 °C. The composition of the image may need some adaptation depending on circumstances.

The image formed is self-supporting, i.e. it can be transferred as a whole, without decomposing, falling apart into pieces, etc. It allows handling by a person, such as a 30 child, without much effort.

The image may change appearance over time. To that extent it may comprise a first pigment or the like such as the ink itself, dissolving in the liquid, whereas a second pigment, for example providing by another ink, remains 35 undissolved in the image. As such the image may change, for instance it may be fluorescent in the beginning, and later not. In a further example the image could be formed with several pens to program how the image will evolve over time. For example, imagine a '+' sign where only the middle part 8 (e.g., where the two lines come together - a dot) is water soluble. Then, the four pieces will fall apart. One can even design more complex images.

Typically the image is released by immersing the 5 substrate and the image into the liquid in a timeframe of from about 0.2 - 20 sec, such as from 1-5 seconds. The time may be somewhat longer or shorter, depending on e.g. thickness and size of the image. Such is not particularly critical; however a slower immersion provides better results. 10 Also the angle under which the substrate is immersed is not critical. However an angle of 15-60 ° of the substrate with the liquid surface provides the best results, the image being on the top or the bottom of the substrate, respectively. The angle depends of characteristics of the substrate, the image 15 and the liquid. For instance, a thicker image may be released under a smaller angle.

Applications are manifold and range from toys for children and others, to products for the decoration of beverages, marketing, to more scientific applications such as 20 floating sensors (see Figure 1-2 below).

The inventors have found after experimenting that writing on water is very specific: in an example it consists of writing a hydrophobic, colored (even fluorescent) polymeric letter/drawing made of only one component (the 25 ink). The image produced will float on or in water.

The present invention is not aimed at coloring or painting a non-liquid surface with one (or more) colors, but rather at coloring or painting a the surface of a liquid, providing a colored image and releasing the image, such as by 30 providing a "wedge", the wedge functioning as a release means. Such a wedge has been found experimentally to be nontrivial .

Upon experimental study it has been identified that writing on a liquid such as water is not at all trivial and 35 further requires very specific measures: it may consists of writing a hydrophobic, colored (even fluorescent) polymeric letter/drawing made of only one component (the ink) that will be floated on water. Likewise an image may be made of more colors .

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Various parameters have experimentally been determined to be of influence.

With respect to wetting, such relates to an ability of a liquid to maintain contact to a certain degree with a 5 solid surface. Such is believed to result from intermolecular interactions when the two are brought together. The degree of wetting (wettability) is determined by a force balance between adhesive and cohesive forces.

Wetting is regarded to be important in bonding or 10 adherence of two materials. Wetting and surface forces that control wetting are also responsible for other related effects, including so-called capillary effects.

At present the substrate is preferably a flat rigid surface. For a planar geometry it is believed the Young's 15 equation holds.

With respect to the Young's modulus, such is a measure of stiffness of an elastic material and is a quantity used to characterize materials. It is typically defined as a ratio of uniaxial stress over uniaxial strain in a range of 20 stress in which typically Hooke's law holds. In solid mechanics, a slope of a stress-strain curve at any point is called tangent modulus. The tangent modulus of an initial, linear portion of a stress-strain curve is called Young's modulus, also known as tensile modulus. It can be 25 experimentally determined from the aforementioned slope of a stress-strain curve e.g. created during tensile tests conducted on a sample of a material under investigation. In anisotropic materials, Young's modulus may have different values depending on a direction of an applied force with 30 respect to the material's structure.

It is noted that the Young's modulus is also commonly called elastic modulus or modulus of elasticity, because Young's modulus is the most common elastic modulus used, but there are other elastic moduli measured, too, such 35 as the bulk modulus and the shear modulus.

Other aspects relevant to the performance of the present invention and optionally included therein are amongst, others : 10 • The 'hydrophobic' polymer composition used to write on the 'hydrophilic' substrate; the composition is typically tailored to a substrate used.

• The 'hydrophilic' substrate, more importantly the 5 surface chemistry of the substrate (such as glass, metals, spoons, plastics, solid-state materials, etc.) • Edible inks suitable with the transfer process.

• Pen markers and paint brushes are preferably compatible with the transfer process.

10 • Printers able to print on present substrates compatible with the transfer process.

• Paper sheets compatible with the ink and water used for the wedging.

• Typical polymers suited for the composition of the 15 ink in the present application (excluding additives, binder resin, release resin, volatile solvent) are: cellulose, cellulose acetate, cellulose acetate butyrate, polyvinyl alcohol, hydrophobic derivatives of methacryolyl chloride polymers and copolymers, acryloyl chloride polymers and 20 copolymers, hydrophobic copolymers of hydroxypropyl methacrylamide and (meth)acrylamide dissolved in low surface tension solvents such as organic solvents (ethyl acetate, ethanol, etc.), hydrophobic polymers, hydrophilic polymers, a combination of both, or water/organic solvents mixtures with 25 a requirement that polymers therein are not or poorly soluble in a liquid such as water alone. It is noted that cellulose derivatives are not toxic, and edible, and are therefore preferred for certain applications. Ethanol and ethyl acetate are already widely used in cosmetics. Ethyl acetate and is 30 one of the organic solvent with the lower toxicity (LD50 in rat of llg/kg).

• Further also additives may be provided to the present composition, such as plasticizers, release agents and dyes in e.g. the polymer/solvent mixture that are packaged in 35 a pen/marker/ink pots with paint brushes.

• Natural hydrophobic inks (including fluorescent and phosphorescent polymers, inks).

11 • Packaging will typically include a range of pen, a range of substrates, a range of pre-printed substrates with logos, sentences, images, etc.

• The floating pattern may have further sensory 5 properties, such as fluorescent and or phosphorescent properties, a sweet taste; dissolve after some period of time in case the technique is applied in gadgets used for decoration of drinks and beverages, etc.

Thereby the present invention provides a solution 10 to one or more of the above mentioned problems.

Advantages of the present description are detailed throughout the description.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates in a first aspect to 15 a method for making a readable image on a liquid according to claim 1.

In an example of the method wherein the image: conveys a message, and/or is an alphanumeric image, and/or 20 is used as a learning tool, such as for children, and/or conveys an image, such as a brand, and advertisement, and/or wherein the image is one or more of homogeneous, permanent, non-permanent, edible, non-edible, and having a 25 Young's modulus of less than 1.5 GPa, preferably less than 1.0 GPa, such as less than 0.8.

The image is preferably substantially homogeneous, such as by forming it in one or more sequence, e.g. by using more colors.

30 In order to convey a message the image is permanent. However, a fading image or the like is in principle also envisaged, such as a non-permanent image.

For food and beverage applications the image may relate to an edible image. Thereto non-toxic and digestible 35 compounds are used.

The Young's modulus of the image is preferably smaller than 0.8 GPa. Such an image provides good flexibility, strength, ease of handling, is adhesive enough to the substrate, etc.

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In an example of the method the composition does not disperse in the liquid for at least 1 minute, and dissolves in the liquid such as after more than 5 minutes, or wherein the composition substantially does not disperse and does not 5 dissolve.

Thereby the image remains readable over a prolonged period of time, to be fully appreciated by a user thereof, such as a consumer, a child, etc.

In some application the image remains intact over a 10 long period of time, e.g. does not dissolve and does not disperse in the liquid. Such a time period may for some application be limited, e.g. up to one minute and be almost infinite for other applications.

In an example of the method the image forms a layer 15 of a thickness of 100 nm-2500 pm, preferably from 500 nm-1000 pm, more preferably from 1 pm-250 pm, such as 2-5 pm.

The thickness of the layer is such that a person needs to be capable of handling it, for example with a sharp object such as a needle, a pen or a object with an edge with 20 a size comparable to the dimension of the floating pattern, or by hand. On the other hand the thickness needs not be too thick, e.g. in view of material used, time needed to form the image, etc. To be handled, in an example the image substantially maintains it properties at human body 25 temperature (for example in the particular application of a skin tattoo). The thickness of the layer may also be scaled with further dimensions thereof; e.g. a relative large image, such as in the order of a few meters by a few meters, may have a thicker layer. Typically the image maintains its 30 structural integrity at least long enough to be recognized by a user.

The present invention relates in a second aspect to an adhesive ink for use in the present method.

Therein the ink comprises a polymer, substantially 35 not being miscible with the liquid. In time, the polymer may dissolve in the liquid. Typically a non-toxic polymer is used, preferably an edible polymer. Such also relates to a monomer or oligomer released from the polymer, if applicable.

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It has been found that the polymer is of sufficient length, in order for the image to be released, to remain intact, etc. An Mw of more than 2500 is typically sufficient. Higher Mw are however preferred, e.g. in terms of integrity.

5 If the polymer/image is aimed at dissolving in the liquid, typically shorter polymers may be used. Mw relates to the Weight average molar mass. The Mw can be determined by dynamic and static light scattering, HPLC, SEC, GPC etc. Typically the Mw is expressed in g/mole.

10 Also a combination of polymers may be present. A

mixture of relative long (at 0.5-5wt.%) and relative short polymers may also be suited.

Within the present invention weight percentages are calculated relative to final weight, e.g. of the composition. 15 It is preferred that the ink dries in a relative short timeframe, such as within seconds, especially when directly used.

The present ink typically relates to a non-lithographic ink.

20 In principle the present ink is suitable for a printer cartridge. As such the present invention also relates to a printer comprising said cartridge, and optionally software to program the image.

In an example .the present invention relates to an 25 ink composition that gets very hard upon polymerizing with water (while floating), e.g. having a relative high Young's modules of more than 2 GPa, in order to provide an image that can be taken out the water and remain solid and robust. For other liquids similar compositions are provided.

30 The present invention relates in a third aspect to a preprint comprising a readable self-supporting image and a support, the image comprising a dried ink according to the invention.

The support is a suitable support for the present 35 invention, e.g. if it relates to "paper", the paper is typically chemically modified, in order to secure release of the image.

The image may be a 'self-made' or premade beverage tattoo. For example, beverage selling companies might be 14 interested to include what could be called 'beverage tattoos' in the package of their drinks. In this case the drink would come with a prepackaged substrate, such as plastic foil, with a logo or image on it that can be made floating in the drink, 5 such as permanent, dissolving or diffusive dispersive drawing.

Other products include a specific pen, and substrates, such as slides, that can be used to make creative images by the users.

10 The present invention relates in a fourth aspect to a kit.

For instance, a toy for children and adults, for example educational toys that can motivate children to learn how to read/write; for example a board for a bath on which a 15 child can write and 'wedge'/transfer the letters in the bath and play and select these; alternatively, the transfer from the liquid (once the letters already float on water) to a new substrate could be made a challenge, where the player needs to try and transfer a floating object while respecting 20 certain boundaries, etc. As an other example the user can also try to redeposit the floating object on another object of interest which is either liquid or solid, or on a skin, with predetermined boundaries to make the game more challenging, move the pattern with a magnet, make separate 25 sentences, etc.

In an example the toy may relate to a puzzle. For instance, one can make a puzzle wherein each piece of the puzzle has a (substantially) different solubility in water.

As such a "programmed" dissolving of the image in the liquid 30 is provided.

In these exemplary embodiments, the toy or the food/beverage product may be composed of several pens/markers (different colors, different tip sizes) including markers, hydrophilic supports (glass slides, hydrophilic - but not 35 water invasive - paper sheets, plastic sheets), a utilization notice and a packaging box. Also the toy and the like may relate to a pre-made product, such as a set of letters and the like.

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The toy can capture the imagination of the public.

It is amusing and playful and can incite creativity in human beings. The wedging transfer is easy and fast and leads to robust transfer of patterns, images, letters or numbers.

5 The wedging phenomenon can stimulate young children to learn how to read and write, and can help them to get familiarized with written language and numbers. The concept may also be applied to toys for the entertainment of children during bathing.

10 The gadgets for the decoration of beverages and drinks can be applied to products that allow making creative floating patterns, for example to decorate or personalize beverages (such as cocktails). Figure 2 illustrates this concept with a few examples.

15 The kit may comprise further components, such as a printer cartridge, software for printing, substrate for the printer, pre-designed images, etc.

The present invention relates in a fifth aspect to a method of learning. Children may be stimulated to form 20 characters, images and the like, and to select possibly upon instruction certain images, characters etc. In a playful environment children are educated.

EXAMPLES

Below follows details of suitable components of 25 present inks.

It is noted that if an ink is used e.g. on glass, it preferably is 'very' hydrophilic (contact angle of almost zero). Such is also the case for liquids other than water. In this case, such as with alcoholic beverages or beer, wherein 30 beer has a very low surface tension because it has natural surfactants, the contact angle can be very small. It has been found experimentally that e.g. in beer and as well as in soapy water the surface tension of the liquid is much lower than e.g. of water, making the present transfer tough.

35 However, it has been found that the present method is still applicable (e.g., for large contact angles of water on the dried ink composition) and/or if the pattern (made of an ink) is first transferred to a liquid such as water, and subsequently transferred to the foam or soapy water. Such 16 provides good results. This further highlights the relative importance of contact angle versus surface tension of the liquid.

The present ink does not relate to a so-called dry-5 erase marker, which is a permanent marker for any surface that is porous.

In general the present ink is composed of 1) a volatile solvent vehicle, 2) a binder resin, 10 3) optionally non fluorinated or fluorinated surfactants, 4) optionally a release agent (generally a silicone-based polymer) and 5) a colorant/dye (triazo, oxazine, diazo, 15 acridine, azo, nanoparticles including metallic nanoparticles, semiconducting nanoparticles, quantum dots, nitroso, dissolved dyes, dispersed pigments - including natural pigments and food additives - oil soluble dyes, thiazol, spirit soluble dyes, azine, xanthane, anthroquinone, 20 nitro, fluorescent/phosphorescent, diphenylmethane, polyoxyalkylene substituted colorants, methine, polymeric dyes, indamine, methoxylated and propyxylated dyes.

Further it may include 6) optionally a flavor (incl. esters and 25 edulcorants) , 7) optionally a fragrance, 8) optionally a magnetic polymer, material or nanomaterial, and 9) optionally a conductive polymer.

30 A typical ink is composed of 150 parts of polyvinyl alcohol, 500 parts of ethanol, 77 parts of pigments and 90 parts of a thinner.

Suitable resin components are: vinylchloride-vinylacetate copolymer, polyvinylbutyral, trimethylolalkane 35 fatty acid ester as separating agent, volatile organic solvent (ketone), alcohols, water or both.

Suitable binder resins are being miscible in the presence of both colorant and volatile solvent vehicle, and 17 which bind to the surface of the substrate as a homogeneous discontinuous film upon evaporation of the solvent vehicle.

Suitable solvents are: low surface tension (high vapor pressure) with 5 respect to the substrate: lower chain aliphatic alcohols and mixtures of those; lower chain aliphatic ketones such as methylethyl ketone or acetone, mixtures of ketones, water, mixture of organic solvents, ethyl acetate or lower aliphatic esters and ethers, alcohols (ethanol, propanol, isopropanol, 10 butanol, n-isomers of butanol), more preferably ethanol and ethyl acetate. Further suitable additives, surfactants, flavors, fragrances, magnetic materials, electrically conductive materials, and/or plasticizers may be added, known to the person skilled in the art.

15 Also fluorescent dyes and pigments (quinine, invisible ink, thymolphthalein, neon colored ink, phosphorescent ink, fluorescent inks, glowing inks under black light, may be added.

Example ingredients of the composition of the ink 20 (including mixture of all of those) are: 1. Block copolymers 2. Conductive polymers, such as polyacetylenes, poly(phenylene sulfide), polyanilines, polyaniline dopants, polypyrroles and pyrrole monomers, polythiophenes, and 25 thiophene monomers.

3. Resin polymer such as: mide Aromatic resins, bisphenol A polymers and epoxy prepolymer resins, Formaldehyde copolymers and epoxies, poly(phenylene oxide) Thermoplastic resins, polysulfones, 30 polyurethanes and Urethane Precursors, Waxes and Oils.

4. Hydrophobic polymers such as: polyacrylics (acrylate polymers - acrylonitrile polymers and copolymers - maleic anhydride copolymers -methacrylate polymers); polyethers; polyfluorocarbons; 35 polyolefins (polyethylene, poly(ethylene-co-acrylic acid) acrylic , poly(ethylene-co-ethyl acrylate) ethyl acrylate , poly(ethylene-co-glycidyl methacrylate), poly ethylene-graft-maleic anhydride, poly(ethylene-co-vinyl acetate) , poly(ethylene-co-methacrylic acid) polypropylene, copolymers, 18 polypropylene-graft-maleic anhydride); amides and Imides (Nylon, polyetherimide, polylauryllactam-block-polytetrahydrofuran, poly maleimide, poly(pyromellitic)/ polycarbonates (poly(propylene)carbonate, poly(bisphenol A) 5 carbonate), polydienes; polyesters; polystyrenes; polyvinyl acetals; polyvinyl and polyvinylidene chlorides; polyvinyl esters; polyvinyl ethers and ketones; and poly vinylpyridine and poly vinypyrrolidone polymers.

5. Hydrophilic polymers such as: 10 polyacrylics (polyacrylamides , poly acrylates); poly(acrylic acid) and variants; polyamine-functional polymers; polyethers (poly(methyl vinyl ether), glycerol propoxylate, 2-Dodecenylsuccinic poly glyceride); polystyrenes (poly styrenesulfonate and variants); poly 15 maleic anhydride copolymers; poly methacrylate, poly ethacrylate, and variants; polyvinyl acids; and polyvinyl alcohols .

6. More generally, polymers and copolymers made out the following monomers: 20 acrylic monomers; epoxide monomers; isocyanate monomers; silicone monomers; styrene and functionalized styrene monomers; alcohols; allyl monomers; amine monomers; anhydride monomers; Biodegradable polymer monomers; bisphenol and sulfonyl diphenol monomers; carboxylic acid monomers; 25 vinyl esters; vinyl ethers; and vinyl halides, amines, amides, and other vinyl monomers.

7. Natural polymers such as:

Carbohydrates and starches cellulose (cellulose, cellulose propionate, Ethyl cellulose, 2-hydroxyethyl 30 cellulose, hydroxyl ethyl cellulose ethoxylate, hydroxyl propyl cellulose, (hydroxyl propyl)methyl, methyl-2-hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyano ethylated cellulose, sodium carboxymethyl cellulose); chitosan and 35 chitin; and Lignins.

8. Poly(ethylene glycol) and poly(ethylene oxide): monofunctional poly(ethylene glycol); homobifunctional poly(ethylene glycol); hetero bifunctional poly(ethylene glycol); poly(ethylene glycol) and oligo(ethylene glycol); 19 poly(ethylene oxide); multi-arm poly(ethylene glycol); and poly(ethylene glycol) - poly(ethylene oxide) copolymers.

9. Silicone polymers and copolymers (mostly as release agents): 5 polysiloxanes

Other Silicone polymers

Silicone oils

Silanes (carbon and F containing) 10. Biodegradable polymers such as: 10 Block copolymers (polycaprolactone-block- polytetrahydrofuran-block-polycaprolactone, poly(ethylene oxide)-block-poly lactide, poly lactide-block-poly(ethylene glycol)-block-poly lactide , poly pyrrole-block-poly (caprolactone) , poly(ethylene glycol)methyl ether-block-15 poly lactide poly lactide, poly(ethylene glycol)-block- poly ( s-caprolactone) methyl ether, poly(ethylene glycol)-block-poly (s-caprolactone) methyl ether, poly(ethylene oxide)-block-poly caprolactone); Caprolactones; hydroxyl butyric Acids; Lactide and Glycolide polymers; 20 polyanhydrides and polyesters; poly phosphazenes; and poly phosphoesters.

11. Polymer additives such as:

Chain transfer agents; cross-linkers; crosslinking Agents and Additives for Epoxides; Plasticizers; 25 polymerization initiator (amine photochemical co-initiators, free radical initiators, organic photo initiators ); polymerization and polymer property modifiers; Stabilizers; Surfactants (anionic surfactants, cationic surfactants, nonionic, zwitterionic surfactants, fatty acids, lipids, 30 proteins); and non-fluorinated and fluorinated surfactants, silanes, thiols, amino silicon and other stabilizers such as ethoxylated phosphoric acid esters.

The invention is further detailed by the accompanying figures, which are exemplary and explanatory 35 of nature and are not limiting the scope of the invention. To the person skilled in the art it may be clear that many variants, being obvious or not, may be conceivable falling within the scope of protection, defined by the present claims .

20

FIGURES

Figure 1 shows photographs of images formed.

Figure 2 shows photographs of images formed.

Figure 3 shows photographs of contact angles.

5 DETAILED DESCRIPTION OF THE DRAWINGS / FIGURES

Figure la-i. Time-laps optical micrographs of the sentence 'TU Delft' being written on water and shuffled around (from 6 to 8 seconds) to form the acronym 'TUD'.

Writing/printing patterns on water has several 10 advantages. Possibly the most appealing ones are to capture the curiosity of a wider public and also to stimulate young children's creativity. Furthermore it brings science at home in a creative and playful manner.

Figure 2a-c. Examples of sentences such as 'I 15 love you', 'Happy birthday' and 'Milk?' written (i.e., transferred) on wine and milk.

In a further example a foamed liquid, such as beer, is used. It has been found experimentally that a written pattern can be transferred to the foam of a beer 20 or to soapy water. However, such is much more difficult compared to just transferring an image on e.g. water. It has been found that e.g. in beer and as well as in soapy water the surface tension of the liquid is much lower than just water, making the transfer tough. However, it has 25 been found that the present method is still applicable, if the pattern (made of an ink) is first transferred to a liquid such as water, and subsequently transferred to the foam or soapy water. Such provides good results. This further highlights the importance of contact angle versus 30 surface tension of the liquid.

In figure 3a-l various substrates, inks (wet and dry) and liquids are used. The results are given below. Substrate Ink Contact angle °Result

1 1 23 OK

35 2 1 60 OK

3 1 104 Not OK

1 1 21 OK

1 1 60 OK

1 1 104 Not OK

21

Dried Ink Water Contact angle “Result

1 1 23 OK

2 1 60 OK

3 1 102 OK

5 Table 1: Experimental results.

In Figure 3:

First row (3a-3c): Contact angle of the ink 21 (before solvent evaporation) on three substrates: 11, 12, 13 10 Second row (3d-3f): Contact angle of three inks (21, 22 and 23) on one substrate (11)

Third row (3g-3i): Contact angle of water (41) on three dried ink compositions (31, 32, 33; e.g., evaporated ink versions of 21, 22, 23 respectively) 15 Fourth row (3j-31): Contact angle of the aqueous-based liquid used for the wedging (41, 42, 43) for one dried ink composition (31).

The invention although described in detailed explanatory context may be best understood in conjunction 20 with the accompanying figures.

Claims (10)

A method for making a recognizable image on a liquid, comprising the steps of: a) providing a liquid, a substrate and a composition immiscible with the liquid, such as ink, the substrate preferably having a has substantially smooth non-permeable surface, and wherein the liquid is a foamed or non-foamed liquid, and wherein the composition has a contact angle with the substrate of less than 80 ° and more than 5 °, b) forming a fixed self-supporting image of the composition on the substrate and, if applicable, allowing the composition to dry, preferably drying at ambient temperature, wherein the dried composition preferably has a contact angle of more than 5 ° on the substrate, at preferably an angle of more than 20 °, more preferably an angle of more than 90 °, wherein the dried composition preferably has a density of 75% -125% of the dic The liquidity of the liquid, preferably 80% -120%, such as 90% -110%, and c) transferring the image to the liquid by slowly immersing the substrate and the image into the liquid leaving the image simultaneously. 2. Method as claimed in claim 1, wherein the image: transmits a message, and / or is an alphanumeric image, and / or is used as a learning tool, such as for children, and / or transmits an image, such as a brand, and advertising and / or wherein the image is one or more of homogeneous, permanent, non-permanent, edible, non-edible, and with a Young's modulus of less than 1.5 GPa, preferably less than 1.0 GPa, such as less than 0.8. 3. A method according to any one of the preceding claims, wherein the composition does not disperse in the liquid for at least one minute, and dissolves in the liquid, such as after more than 5 minutes, or wherein the composition does not substantially disperse and does not dissolve. Method according to any of the preceding claims, wherein the image forms a layer with a thickness of 100 nm -2500 µm, preferably of 500 nm-1000 µm, more preferably 1 µm -250 µm, such as 2-5 µm. Adhesive ink for use in a method according to any of the preceding claims, wherein the dried composition has a contact angle of more than 5 ° on the substrate, preferably an angle of more than 20 °, more preferably an angle of more than 90 °, wherein the dried ink preferably has a density of 0.8-1.2 kg / l, the ink consisting of: 10-50% by weight of at least one polymer insoluble in the liquid, the at least one polymer has an average molecular weight Mw of more than 2500, preferably with an Mw of more than 10,000, more preferably an Mw of more than 20,000, such as an Mw of more than 25,000, 10-70% by weight of solvent, 1-20 % by weight of one or more of a pigment, colorant, colorant, 00-10% by weight plasticizer, and 00-10% by weight wetting agent. 6. Preprint comprising a recognizable self-supporting image and a carrier suitable for introduction into a liquid, the image comprising a dried-up ink according to claim 5, the carrier selected from a foil, a paper, and a coated paper, in which the image has a contact angle of more than 5 ° with the liquid, preferably an angle of more than 20 °, more preferably an angle of more than 90 °, wherein the image preferably has a density of 75% -125% of the density of the has a liquid, more preferably 80% -120%, such as 40 and 90% -110%, in which the image preferably has a Young's modulus of less than 1.5 GPa, in which the image does not disperse in the liquid for at least one minute, and dissolves in the liquid, such as after more than 5 minutes, or wherein the image substantially does not disperse and does not dissolve. 7. Kit consisting of a package, one or more of a color provider, such as a pen, a marker, comprising an ink according to claim 5, a substrate for forming a fixed self-supporting image, optionally one or more of a brush, a roller, a spray, a printer cartridge, software for printing, a sub-15 street for a printer, and a pre-designed image. 8. Method of learning, comprising the steps of providing a kit according to claim 7, forming one or more self-supporting alphanumeric characters and selecting a specific example thereof. 9. A picture evolving over time, such as within 10 minutes, comprising at least two inks, the at least two inks being selected from: i) at least one first ink according to claim 5, and ii) at least one second ink, optionally according to claim 5, wherein the at least one first ink has a substantially different distribution and / or dissolution behavior in a liquid relative to the behavior of the at least one second ink. A method of programmed image degradation, comprising the steps of: providing an image according to claim 9, preferably making a recognizable image on a liquid according to claims 1-4, and dissolving the image in the time.