The present invention is drawn to a device for perfuming ambient air or closed spaces. The said device comprises water or an appropriate hydrophilic solvent containing said volatile active ingredient and an absorbing material chosen from superabsorbents, starch based systems, chemically modified cellulose and natural gum and which are capable of forming a gel with water or said hydrophilic solvent, both components being adapted to be mixed with each other in order to achieve the diffusion of said volatile ingredient from the said gel. The components are mixed with each other to form said gel from which the perfume or a deodorizing or sanitizing agent, or an insect repellent, diffuses uniformly and over a prolonged period of time into the surrounding air.

The present invention relates to the field of perfumery. It relates, more particularly, to a gel device which allows for an effective and prolonged evaporation of an active volatile substance, like a perfume, an insect repellent or a deodorizing or sanitizing agent.
The use of various devices for the diffusion of volatile compounds, for example perfumes, sanitizing agents, insect repellents, and the like, has become more and more current in recent years. For example, air-freshening devices or deodorizers are currently used in practically all households to mask bad odors or to impart fragrances to the ambient air. The known devices used for the diffusion of volatile compounds into the surroundings make use of various principles. As an example, one can mention here dispersing devices of the spray type, aerosols or mechanical. Other examples include plastic packing elements enclosing the active ingredients in liquid form. Typically, the diffusion of the active ingredient takes place through membranes permeable to the vapors of said ingredient.
One class of systems capable of diffusing active volatile ingredients are solid state devices consisting of solid materials or carriers impregnated with an active ingredient. Such devices may be formed of various materials which are capable of absorbing the ingredient and subsequently releasing it in a more or less controlled manner. Examples of such known materials include gels, such as agar-agar or sodium stearate gels, synthetic polymer resins, or blocks of mineral material, e.g. plaster or silica. It is even possible, for some purposes, to have active ingredients absorbed on paper or cardboard in order to obtain a more or less solid carrier device for diffusing the volatile ingredient thus absorbed. Often, solid devices are designed to be non-wetting, i.e. to be capable of effectively retaining the liquid active volatile material and only allowing the diffusion of the vapors of said material.
In general, diffusing devices are to be activated by the customer. Such devices often comprise a pouch or sachet containing the active ingredient and which is hermetically sealed. In order to release the ingredient, the customer will have to pierce the sachet, make it burst or peel off a certain part of it in order to let the active ingredient escape into the surroundings. Other devices comprise multiple compartments having a rupturable joint between them, at least one of these compartments being of a material which is not permeable to the vapors of the ingredient and the other being permeable. Devices of this kind are activated by applying pressure to the non-permeable compartment, upon which the rupturable joint opens to let the active ingredient flow into the compartment which is permeable to its vapors. A diffusing device of this kind is described in U.S. Pat. No. 4,798,288, for example.
Despite prior known diffusing devices for active volatile ingredients, there is still a need for diffusing devices which are capable of releasing effective amounts of active ingredient into the surroundings, in general closed spaces, and this for a prolonged period of time.
According to the invention this object is attained by a device for the diffusion of a volatile active ingredient, comprising an appropriate hydrophilic medium, said volatile active ingredient and an absorbing material selected from superabsorbent substances, starch based systems and chemically modified cellulose, said absorbing material being capable of forming a gel with said hydrophilic medium susceptible of enclosing said volatile active ingredient within and of permitting the diffusion of said volatile ingredient from the gel upon exposure of the latter to air.
The invention also relates to a method for the diffusion of active volatile substances into ambient air, in particular air in closed spaces, the method comprising exposing a gel resulting from mixing a solution, emulsion or suspension of a volatile active ingredient in an hydrophilic solvent with an absorbing material selected from superabsorbent substances, starch based systems, chemically modified cellulose and natural gums, so as to form said gel, to air.
We have found that the diffusion systems according to the invention provide a very uniform and prolonged diffusion of the active ingredient.
As active ingredient, there can be used for example perfumes, resulting in air-fresheners. Other suitable active ingredients comprise deodorizing or sanitizing agents, or insect repellents, or yet any other volatile materials capable of imparting perceptible and desirable benefits to the quality of the air into which they are diffused.
The absorbing material according to the present invention, intended to be mixed with the hydrophilic medium, preferably an aqueous solution, emulsion or suspension of the volatile active ingredient is preferably a so-called superabsorbent material or substance. These are materials which are capable of absorbing large amounts of water or other hydrophilic media. In the context of the present invention, superabsorbents are organic synthetic polymers containing acrylic acid or methacrylic acid, or a salt thereof, these polymers being capable of absorbing between about 50 and 200 times their own weight of water or hydrophilic solvent. Amongst the most current superabsorbents one can cite the cross-linked sodium polyacrylate/polyacrylic acid polymers. Superabsorbents of this type are commercially available under the names of Salsorb(copyright) (Allied Colloids Ltd.) and Cabloc(copyright) (Stockhausen GmbH).
The superabsorbents of the invention, which are in the form of a fine powder, should preferably have a particle size from about 50 to about 500 microns in order to provide a smooth gel upon admixture of the components of the diffusion device. Powders with larger or lower particle sizes than those mentioned can also be used, but they will result in coarser, or, respectively finer, gels.
According to the invention, best results were obtained with the commercial cross-linked sodium polyacrylates sold under the tradename of Salsorb(copyright). However, it goes without saying that the present invention is not limited to the above-specified materials. There can also be used other types of superabsorbents, for example polymers of other salts of acrylic acid or methacrylic acid, polyacrylamides, polyacrylic esters, polymethacrylic esters, copolymers of acrylates, methacrylates, acrylic acid or methacrylic acid with vinyl acetate, vinyl alcohol or maleic anhydride, isobutylene-maleic anhydride copolymers, saponified graft polymers of acrylonitrile or graft polymers of starch and acrylic acid.
Yet other absorbing materials which can be used in the present invention are acrylic polymers other than those cited above, e.g. acrylamide polymers, starch based systems, e.g. cellulose, gluten, chemically modified cellulose, e.g. carboxymethylcellulose, or cellulose ethers.
The absorbing material as specified above is mixed with a hydrophilic solvent, preferably water or a water based medium possibly containing a small amount of ethanol or a similar solvent, and the volatile active ingredient. In general, the hydrophilic solvent will contain the volatile active ingredient. To this end, there will in general be used a solution, suspension or emulsion of the active ingredient in said hydrophilic solvent.
The hydrophilic solvent is an essential element of the present invention. Its presence is mandatory to achieve the desired regular and prolonged evaporation of the active ingredient. It can be said that said solvent acts as an evaporation aid. Without the presence of the solvent, the evaporation of the active ingredient generally occurs at such a low rate that an effective working of a device according to the present invention is not assured. A further advantage is that a uniform distribution of the active ingredient in the absorbing material is achieved.
When said solution, suspension or emulsion is prepared, it may be advantageous to use an emulsifying agent, although this is optional. In general, a surfactant will be used as emulsifying agent. Systems have been prepared and found to function satisfactorily without the use of a surfactant, where the active volatile ingredient, e.g. perfume, and the water are held in suspension by the gelled structure. Where surfactants are used, nonionic surfactants are preferred. Examples of this class of surfactants include ethoxylated sorbitan esters which are available under the trade names Span(copyright) (origin: ICI) and Brij(copyright) (origin: ICI). Ethoxylated saturated fatty esters like those sold under the names of Cremophor(copyright) (origin: BASF) and Lutensol(copyright) (origin: BASF) can also be used. Further examples of appropriate nonionic surfactants include alcohol ethoxylates, polyethylene glycol esters and ethylene oxide/propylene oxide copolymers. These surfactants can be present in the aqueous solution, emulsion or suspension of the active ingredient in concentrations varying from 0 to 10% by weight, preferably from 1 to 3% by weight, relative to the total weight of said resulting solution, emulsion or suspension.
As mentioned above, the active ingredient which will be diffused by the device of the invention can typically be a perfuming ingredient, a deodorizing or sanitizing agent or an insect repellent.
As a perfume or perfuming ingredient there can be used in the device of the invention any ingredient or mixture of ingredients currently used in perfumery. The latter can be made of discreet chemicals; more often, however, it will be a more or less complex mixture of volatile ingredients of natural or synthetic origin. The nature of these ingredients can be found in specialized books of perfumery, e.g. in S. Arctander (Perfume and Flavor Chemicals, Montclair N.J., USA 1969) or similar textbooks of reference, and a more detailed description thereof is not warranted here.
Although special mention has been made hereinabove of the perfuming effect that can be exerted by the invention device, the same principles apply to the manufacture of analogous devices for the diffusion of deodorizing or sanitizing vapors, the perfume base being then replaced by a deodorizing composition, a bactericide, an insecticide, an insect repellent or even an insect attractant. By the term xe2x80x9csanitizing vaporsxe2x80x9d, we refer here not only to the vapors of those substances which can enhance the degree of acceptance of surrounding air to the observer, but also to those substances which can exert an attractant or repellent effect towards certain species of insects, for instance towards houseflies or mosquitoes, or else, which can have bactericide or bacteriostatic activity. It goes without saying that mixtures of such agents can also be used.
The above-identified compounds will be admixed with the water or an appropriate hydrophilic solvent in a quantity which can range, for all types of gels, from about 0.1% to about 15% by weight of the resulting solution, emulsion or suspension, preferably about 1 to 6% by weight. Upon use of superabsorbents, these values may slightly differ from those above which are valid for conventional absorbing media. We found that the incorporation of larger amounts of active ingredient is possible. For superabsorbents of the sodium polyacrylate/polyacrylic acid polymer type, values from about 0.1% to about 20% by weight of active ingredient in the solution, emulsion or suspension can be attained, the preferred range being from about 1% to about 6% by weight. It is clear that in cases where small amounts, such as for example 0.1%, are used, there will often be observed only a minor effect and the lifetime of the device will be considerably short. The upper limit for the amount of active ingredient that can be used, on the other hand, shall be determined by the ability of the absorbing material to absorb the solution.
The absorbing material and the solution, emulsion or suspension containing the active ingredient will be mixed together in order to form the gel device capable of releasing the ingredient. When a superabsorbent is used as absorbing material, it will be present in an amount of from about 0.1% to about 15%, preferably from about 2% to 5% relative to the total weight of the resulting gel, the balance being the weight of the solution, emulsion or suspension containing the ingredient.
The gel obtained after mixing the absorbing material with the hydrophilic solution, suspension or emulsion containing the active ingredient, diffuses the active ingredient uniformly and over a prolonged period of several weeks, unlike prior known diffusion devices. Moreover, the device can also provide a use-up cue when all the active ingredient is exhausted and the absorbing material is formed of a superabsorbent substance. Such superabsorbent materials (which before mixing are in the form of a fine powder), do in fact shrink from the gel form into a conglomerate of the originally present particles upon exhaustion of the volatile active ingredient. The appearance of these materials can then be described as being that of wet opaque crystals sticking to each other and the used-up article therefore is easily distinguishable from the gel originally obtained upon mixing the components mentioned before.
The end point cue is even more visible when a water-soluble dye is incorporated into the dry superabsorbent, i.e. before mixing the latter with the solution, emulsion or suspension of the volatile ingredient in the hydrophilic medium. Before activation of the device, the dye is not distinguishable from the superabsorbent powder. Yet, when the superabsorbent containing the dye is mixed with the solution, emulsion or suspension of the active ingredient, the dye colors, as a consequence of the presence of water and the distribution of the dye in the gel, thus giving the user a clear indication that the diffusion device is now activated. The presence of the dye also facilitates the recognition of the end point of the device, due to the change between the original gel and the particles forming upon exhaustion of the diffusion device. A further advantage of the presence of the dye is that the user can follow the mixing or activation process of the device of the invention with his eyes thanks to the color appearance. Only quite low amounts of dye are necessary to obtain the desired effects, and typical concentrations are from about 0.01% to about 1%, preferably 0.1% by weight, relative to the weight of the superabsorbent.
An advantage of the device according to the invention is that, after exhaustion, it can be easily replenished simply by adding a fresh emulsion or solution containing an active ingredient to the used up material. The device will then function practically as good as a device which has been activated for the first time.
The activation of an air-freshening device according to the present invention can be accomplished in different ways.
In one embodiment of a device of the invention, the absorbing material and the solution, emulsion or suspension containing the active ingredient are separated from each other. The customer, after buying these two components, activates the device simply by mixing the components, resulting in an air-freshener which gives the described prolonged diffusion of active ingredients.
Air-freshening devices according to a further embodiment of the present invention already contain the gel resulting after admixture of the absorbing material and the solution, emulsion or suspension containing the active ingredient. The container in which the gel is found is sealed, in order not to allow diffusion of the active ingredient into the surroundings. The customer will then activate the device simply by opening the container, after which the active ingredient will evaporate. This embodiment is possible because the gels obtained after mixing of the above-mentioned ingredients are perfectly stable for a period of several months and can hence be stored.
According to a preferred embodiment of the invention, the diffusing device shall comprise separate compartments for the absorbing material and for the hydrophilic medium containing the volatile active ingredient, means being provided to permit the activation or mixing step being carried out by the user himself. The two above-mentioned components can e.g. be in the form of two closed, separate and preferably transparent containers, each containing one of the components. The user can then open both containers and activate the diffusion device by mixing the components. In a preferred embodiment, the components will be arranged in a packing having at least two compartments and a rupturable joint or wall common to both compartments. The components are each separately lodged in one of the said compartments. The two components can then be mixed by rupturing or bursting the joint or wall, for example by applying pressure to at least one of the compartments. The two components can subsequently be easily mixed by shaking the package. A top layer or closure covering at least a part of the compartment will then be removed to allow the diffusion of the active ingredient into the surrounding air. A package of this type, used for a different purpose, is described for example in U.S. Pat. No. 4,798,288, the content of which is hereby included by reference. The person skilled in the art of air-fresheners will appreciate that many other types of commonly used air-freshener packages will fulfill the objective of the invention.
In another preferred embodiment of the invention, at least a part of the wall of the compartment containing the absorbing material is permeable to the vapors of the active ingredient, closure being then not necessary. When the joint between the compartments is broken, the solution, emulsion or suspension containing the active ingredient will flow into the compartment containing the absorbing material, forming a gel. The active ingredient can then diffuse into the surrounding air through the walls of the compartment, the removing of a top layer or closure not being necessary in this particular case.
In a further preferred embodiment of the air-freshener device according to the present invention, said device comprises a reservoir containing an appropriate hydrophilic solvent. The gel is located in the upper part of said reservoir. Means are provided to ensure an appropriate supply of a hydrophilic solvent to the gel. As hydrophilic solvent, there will be used the same liquids as for the preparation of the solution, emulsion or suspension containing the active ingredient. The most preferred hydrophilic solvent is water.
By this, the gel will remain completely moistened by the liquid throughout its whole lifetime, i.e. until all active compound has evaporated. As mentioned above, it was found that the hydrophilic solvent, in particular water, acts as an evaporation aid for the active ingredient. There is observed a lower evaporation rate for said active ingredient if the gel is not properly moistened, respectively hydrated, by a hydrophilic solvent, even if there remains an amount of active ingredient in the gel which should not yet give rise to said lower evaporation rate. By keeping the gel sufficiently moistened, an efficient and complete evaporation of the active ingredient is ensured, resulting in a prolonged lifetime of the air-freshener.
Devices for providing an appropriate supply of hydrophilic solvent to the gel are known to a person skilled in the art. For example, one possibility is to provide said supply by capillary action. Simple capillaries or small tubes, made from, for example, glass or plastics, often give sufficient results. The best results, however, were obtained by using a wick. Of course, the material and dimensions of such wick must be chosen in a way that a sufficient amount of solvent is supplied to the gel to keep it entirely moistened. The necessary amount depends on the amount of gel and its absorbing properties.
A large number of organic and inorganic materials can be used for the wick. Examples for appropriate inorganic materials include porous porcelain material, glass fiber, or asbestos, in combination with a suitable binder such as, for example, gypsum or bentonite. It is also possible to prepare wicks from powdered mineral materials, such as, for example, clay, talc, kieselguhr, alumina, silica or the like, singly or in combination with, for example, wood flour, carbon powder, or activated carbon, using an appropriate glue. Organic materials include felt, cotton, pulp, woven and non-woven cotton fibers, woven and non-woven synthetic fibers, and porous polymeric foams and sponges.
We could obtain particularly advantageous results with a wick consisting of a polyester filling surrounded by perforated polypropylene. Such a material is commercially available at Baumgartner Papier SA, Switzerland.
The wick must be able to transport the hydrophilic solvent, in general water, at least as quick to the gel as the solvent evaporates from the surface of the gel.
As mentioned above, in this embodiment of an air-freshener according to the present invention, the gel will be in a container adjacent to the reservoir and connected to it by an appropriate supply, preferable a wick. It is preferred when the gel sits on a piece of absorbing material connected to the wick, like thick, absorbent paper, for example filter paper, in order to ensure a regular distribution of the solvent in the gel.
The container which takes up the gel is covered by a material which is permeable to the vapors of the active ingredient, in order to prevent the gel from falling out. To this end, a mesh may be used.
The material permeable for the vapors is sealed by an appropriate closure which can easily be removed by the customer after purchase, in order to activate the air-freshening device according to the present invention.
In this preferred embodiment of an air-freshener according to the present invention, it is possible to simply add new water to the reservoir once it is empty, as long as there remains active ingredient in the gel. By this, it is for example possible to incorporate larger amounts of fragrance in the gel and provide air-freshening device with a prolonged lifetime in which the reservoir simply has to be refilled from time to time by the customer to keep the device working.
After activation, the gel of the diffusion device of the invention should preferably have an evaporation surface of from about 10 to about 60 cm2, preferably of from about 20 to about 40 cm2, in order to allow an effective diffusion of the active ingredient.
The device of the present invention allows a linear and effective release of fragrance, with only low amounts of fragrance remaining in the gel after exhaustion of the perfume or the other active ingredient.


A scented ink composition suitable for use in ink jet printing which generates aromas during printing and produces scented printed articles such as greeting cards.

The invention relates to scented ink compositions for ink jet printers which generate aromas from the printer during operation and scented printed articles produced therefrom.
The pleasing effects of fragrant substances has lead to many products and methods for providing pleasant aromas to the olfactory senses such as perfumes, oils, soaps, lotions, creams, aromatic candles, room fresheners, potpourri, etc. In recent years there has been an increased interest in fragrances by those who believe the aromas from essential oils have therapeutic effects. The use of such oils is commonly referred to as aroma therapy but therapeutic benefits beyond the pleasing effects of their aroma has not been recognized by the FDA.
Apparatus for releasing fragrant aromas into a room have varied widely from manual to automatic dispensers such as the apparatus described in U.S. Pat. Nos. 2,618,892; 3,400,890 and 4,484,768 and the battery operated aerosol, gel and pump air fresheners of AIR DELIGHTS(trademark) of Portland Oreg.
The media from which fragrant substances are released has also varied widely from liquids, gels, solids and aerosols. The diffusion of fragrant vapors from polymers described in U.S. Pat. No. 3,567,119 is one example. The use of scented inks, paints and marking compositions (crayons) to prepare scented articles is well known as described in U.S. Pat. Nos. 2,578,425; 5,474,805 and 5,577,947. These inks, paints and marking compositions have been adapted for printing methods other than ink jet printing.
Ink jet printing has experienced a significant increase in use in recent years due to reduced equipment cost, color availability and improvements in print speed and print resolution. There are two major categories of ink jet printingxe2x80x94xe2x80x9cDrop-on-Demandxe2x80x9d and xe2x80x9ccontinuousxe2x80x9d ink jet printing. For continuous ink jet printing, a conducting ink is supplied under pressure to an ink nozzle and forced out through a small orifice. Prior to passing out of the nozzle, the pressurized ink stream proceeds through a ceramic crystal which is subjected to an electric current. This current causes a piezoelectric vibration equal to the frequency of the AC electric current. This vibration, in turn, generates the ink droplets from the unbroken ink stream. The ink stream breaks up into a continuous series of drops which are equally spaced and of equal size. Surrounding the jet, at a point where the drops separate from the liquid stream in a charge electrode, a voltage is applied between the charge electrode and the drop stream. When the drops break off from the stream, each drop carries a charge proportional to the applied voltage at the instant at which it breaks off. By varying the charge electrode voltages at the same rate as drops are produced it is possible to charge every drop to a predetermined level. The drop stream continues its flight and passes between two deflector plates which are maintained at a constant potential. In the presence of this field, a drop is deflected towards one of the plates by an amount proportional to the charge carried. Drops which are uncharged are undeflected and collected into a gutter to be recycled to the ink nozzle. Those drops which are charged, and hence deflected, impinge on a substrate traveling at a high speed at right angles to the direction of drop deflection. By varying the charge on individual drops, the desired pattern can be printed.
In a typical xe2x80x9cDrop-on-Demandxe2x80x9d ink jet printing process, a fluid ink is forced under pressure through a very small orifice of a diameter typically about 0.0024 inches in the form of minute droplets by rapid pressure impulses. The rapid pressure impulses are typically generated in the print head by either expansion of a piezoelectric crystal vibrating at a high frequency or volatilization of a propellant within the ink by rapid heating cycles. The piezoelectric crystal expansion causes the ink to pass through the orifice as minute droplets in proportion to the number of crystal vibrations. Thermal jet printers employ a heating element within the print head to volatilize a propellant and form droplets in proportion to the number of on-off cycles for the heating element. The ink is forced out of the nozzle when needed to print a spot on a substrate as part of a desired image. The minute droplets may be energized to achieve an electrical charge and deflected as in the continuous ink jet printing. Conventional ink jet printers are more particularly described in U.S. Pat. Nos. 3,465,350 and 3,465,351.
Another type of ink jet printing process is an electrostatic ink jet process which employs an electrostatic field to draw the ink through the nozzle to the substrate. Charged ink droplets are drawn to an oppositely charged platen behind the receiving substrate. Such devices have been developed by Technology International Corp. of Boulder, Colo., under the trade name ESIJET(trademark).
To operate satisfactorily within an ink jet printer, the ink has many requirements. The ink must exhibit low viscosity values (preferably below 20 centipoise at 25 C), contain no large particulate matter (typically below 5 xcexcm), and be sufficiently stable so as not to dry and clog the jet orifice when not in use. For xe2x80x9ccontinuousxe2x80x9d ink jet printing, the ink must be conductive with a resistivity value typically below 10,000 ohms and the unused ink is preferably recyclable. Secondary factors must also be considered, such as avoiding the generation of flammable vapors during use and minimizing the impact on the environment.
Operating satisfactorily within an ink jet printer addresses only some of the requirements of the ink. The ink must also dry rapidly and bond to the substrate to which it is applied such as coated and uncoated papers to provide printed images or indicia without smearing.
These inks sometimes do not contain a binder for the pigment or dye therein and these pigments or dyes to must be absorbed into the surface of the print medium to provide stable printed images or indicia. Some of the requirements of jet printing inks are described in U.S. Pat. No. 4,258,367.
It is desirable to provide jet inks with more versatile properties. It is also desirable to provide a simple means for dispensing fragrances and for forming scented printed articles such as greeting cards with fragrant printed images and indicia.
General objectives of this invention are the generation of fragrant aromas from printing operations and the production of scented printed articles, particularly those with paper substrates.
A specific object of this invention is to provide a printing ink for ink jet printing which generates fragrant aromas during printing and produces fragrant printed articles.
An additional object of this invention is to provide a printing ink for ink jet printing which generates fragrant aromas during printing and produces fragrant printed articles when used in conventional ink jet printers without a loss in print quality.
Another object of this invention is to provide scented printed articles with fragrant images and/or indicia obtained by ink jet printing.
Further objects of the present invention will become apparent from the detailed disclosure and claims herein.
The present invention provides jet inks which generate fragrant aromas through the incorporation of at least one fragrant oil which vaporizes during printing with an ink jet printer and vaporizes from the printed images and indicia on the surfaces of printed articles formed from the jet ink. The jet inks comprise at least one coloring agent selected from pigments and dyes and a carrier for the color agent. The one or more fragrant oils are soluble or dispersible in water, alcohol or glycol solvent which is compatible with the carrier for the coloring agent or is the carrier for the coloring agent.
The printed articles comprise a substrate with an absorptive surface with an image and/or indicia printed thereon by ink jet printing. The image and indicia comprise a coloring agent bound to the absorptive surface either by a binder within the substrate, a binder within the image/indicia or both a binder within the substrate and the image/indicia. Where the image/indicia contains a binder, it may be cured in place, preferably by a cationic curing mechanism.
The jet inks of this invention may generally be comprised of the following components:
a) at least one fragrant oil which vaporizes when jetted from a nozzle of an ink jet printer,
b) one or more coloring agents selected from pigments and dyes, preferably in an amount of about 10 wt % of the total ink composition and
c) a carrier for said coloring agent, preferably selected from water, plasticizers, alcohols and glycols,
d) optionally, binders which are soluble or dispersible in the carrier for the coloring agent,
e) optionally, performance additives such as pigment dispersants and defoamers and
f) optionally, a propellant such as low boiling solvent other than the carrier for the coloring agent.
The one or more fragrant oils are soluble or dispersible in the carrier for the coloring agent which is typically water, an alcohol or glycol solvent or a plasticizer. The fragrant oil in said ink composition is preferably used in an amount within the range of 0.05 wt % to 5 wt %, preferably 0.1 wt % to 2 wt %. Essentially any fragrant oil soluble or dispersible in the carrier at these levels can be used in this invention. These fragrant oils vary widely in composition and aroma and include commercially available perfumes for both men and women as well as commercially available scents for air fresheners and candles. Also included are the essential oils used in aroma therapy which include the following oils available from WORLD DIRECT, Paola, KS:
Basil (Ocimum basilicum)
Bergamot (Citrus aurantium bergami)
Birch (Betula alleghaniensis)
Cedarwood (Cedrus atlantica)
Chamomile, Roman (Chamaemelum nobile)
Cinnamon Bark (Cinnamomum verum)
Cistus (Cistus ladaniferus)
Clary Sage (Salvia sclarea)
Clove (Eugenia caryophyllus)
Coriander (Coriandrum sativum)
Cypress (Cupressus sempervirens)
Davana (Artemisa pallens)
Dill (Anethum graveolens)
Eucalyptus (Eucalyptus globulus)
Fennel (Foeniculum vulgare)
Fir (Abies alba)
Frankincense (Boswellia carterii)
Galbanum (Ferula gummose)
Geranium (Pelargonium graveolens)
Ginger (Zingiber officinale)
Helichrysum (Helicrysum italicum)
Hyssop (Hyssopus officinalis)
Jasmine (Jasminum officinale)
Juniper Berry (Juniperus communis)
Laurus Nobilis
Lavender (Lavendula officinalis)
Lemon (Citrus limon)
Lemongrass (Cymbopogon flexuosus)
Margoram (Origanum majorana)
Melaleuca (Melaleuca alternifolia)
Mountain Savory (Satureja montana)
Myrrh (Commiphora molmol)
Myrtle (Myrtus communis)
Nutmeg (Myristica fragrans)
Orange (Citrus aurantium)
Oregano (Origanum compactum)
Patchouly (Popostemon cablin)
Pepper, Black (Piper nigrum)
Peppermint (Mentha piperita)
Petitgrain (Citrus aurantium)
Ravensara
Rose, Turkish (Rosa damascena)
Rosemary (Rosmarinus officinalis)
Rosewood (Aniba rosaeodora)
Sage (Salvia officinalis)
Sandalwood (Santalum album)
Spikenard
Spearmint (Mentha spicata)
Spruce (Picea mariana)
Tangerine (Citrus tangerina)
Tarragon (Artemisia dracunculus)
Thyme (Thymus vulgaris)
Vetiver
Vitex
White Lotus (Nymphaea lotus)
Wild Tansy (Tanacetum vulgare)
Ylang Ylang (Cananga odorata)
and the like.
The ink formulations of the present invention contain a coloring agent which is capable of being sensed visually, by optical means, by magnetic means, by electro conductive means or by photoelectric means. Suitable coloring agents are those used in conventional ink jet formulations. The coloring agent is typically a dye or pigment and can be selected from a variety of organic and inorganic pigments and dyes. Examples include phthalocyanine dyes, carbon blacks, fluorescent naphthalimide dyes and others such as cadmium, primrose, chrome yellow, ultra marine blue, iron oxide, zinc oxide, titanium oxide, cobalt oxide, nickel oxide, etc. Other examples of coloring agents include those described in U.S. Pat. No. 3,663,278 and U.S. Pat. No. 4,923,749. Reactive dyes such as leuco dyes and diazonium compounds are also suitable. The total amount of coloring agent is typically from about 0.01-10 wt. % of the total ink formulation. The pigments such as carbon black are of a size less than 5 xcexcm.
Water and low molecular weight (low viscosity, low boiling) alcohols and glycols can be used as carriers for the coloring agents. The low boiling alcohols will also function as a propellant where the ink is used in thermal jet printing. Suitable examples of alcohols include monovalent alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-amyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, mixtures thereof and the like. Suitable examples of glycols include ethylene glycol, polyether polyols, diethylene glycol, triethylene glycol, 1,2-propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, glycol, trimethylol propane, 1,6-hexanediol, pentaerythritol, trimethylol propane, tetramethylolpropane, dipentaerythritol mixtures thereof and the like. Solvents which may be mixed with the alcohols or glycols are ketones, aldehydes, ethers, esters, hydrocarbons, glycol ethers and lactones. Suitable hydrocarbons include hexane, heptane, octane, decane, cyclopentane, cyclohexane, benzene, toluol, xylol, ethylbenzene mixtures thereof and the like. Suitable hydrocarbon halides include carbon tetrachloride, ethylene dichloride, trichloroethylene, tetrachloroethane, dichlorobenzene mixtures thereof and the like. Suitable ether type solvents include butyl ether, ethylene glycol-diethylether, ethylene glycolmonoethyl ether, ethylene glycol-monobutylether mixtures thereof and the like.
Suitable ketones include acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclohexanone mixtures thereof and the like. Suitable esters include ethyl formate, methyl acetate, propyl acetate, butyl acetate, phenyl acetate, ethylene glycol-monoethyl ether acetate, methylpropionate mixtures thereof and the like.
Plasticizers such as those described in U.S. Pat. No. 3,663,278, may also be used as carriers to aid flexibility of the image formed and/or reduce the viscosity of the ink. Suitable plasticizers include adipic acid esters, phthalic acid esters and ricinoleate acid esters, citrates, epoxides, glycerols, hydrocarbons, chlorinated hydrocarbons, phosphates and the like.
The amount of carrier can range from 10 to 95 wt. % of the total ink formulation. Preferably, the carrier comprises about 75 wt. % of the total ink formulation where the carrier evaporates on the substrate.
Optional binders include those which are soluble or dispersible in the carrier (plasticizers, water, alcohols or glycols) for the coloring agent. This includes those binders used in conventional jet printing inks such as acrylic polymers as described in U.S. Pat. No. 5,244,496 and polyethylene oxide polymers. Suitable binders also include sugar and alcohol binders (U.S. Pat. No. 5,711,791), cellulosic polymers (U.S. Pat. No. 5,755,860), those described in U.S. Pat. Nos. 5,672,198; 5,663,217 and 4,990,186 and the reactive binders disclosed in U.S. Pat. No. 5,641,346 and copending application Ser. No. 08/792,827, filed Jan. 30, 1997, assigned to the same assignee herein and entitled xe2x80x9cUV or Visable Light Initiated Cationic Cured Ink for Ink Jet Printingxe2x80x9d.
The ink formulations of the present invention typically comprise from 5 to 15 wt % optional binder, based on the total composition. Preferred amounts range from 1-10 wt. % optional binder, based on the total composition. Preferred levels of optional binder will depend on the polymer(s) used and their viscosity.
Optional additives which may be incorporated to improve the properties as jet printing inks including dispersing agents to help solubilize the pigment or dye, fillers, defoaming agents, flow adjusters, leveling agents or cobwebbing preventative agents. Illustrative examples of flow adjusters are low molecular weight organopolysiloxanes such as methylpolysiloxanes which may be used in an amount of 0.01-10 wt. % based on weight of the total ink formulation. An illustrative example of a defoamer is Anti-Musal JIC, which may be used in an amount of 0.01-10 wt. % based on the weight of the total ink formulation. Illustrative examples of leveling agents are low molecular weight polysiloxane/polyether copolymers and modified organic polysiloxanes, which may be used in an amount of 0.01-10 wt. % based on the weight of the total ink formulation.
Other suitable additives desired for jet ink printing are those which reduce bacterial growth (Towisyl 75), modify viscosity, which provide wettability (butylcarbitol), humectants which prevent the composition from drying out within the print head (polyethylene glycols), which enhance the conductivity of the ink formulation for use in continuous ink jet printers and photostabilizers which prevent polymerization of inks by natural or ambient light. Other suitable additives include oil, weatherability improvers such as UV light absorbers, flexibilizers (oil) and fillers.
Where the ink composition is to be used in a thermal jet printer, it contains a propellant, which is typically a low boiling liquid such as a low molecular weight alcohol or water and is typically the carrier for the coloring agent. Low boiling solvents which are not carriers for the coloring agent can also be used as propellants. The amount of propellant can range from 10 to 95 wt. % of the total ink formulation. Preferably, the propellant comprises about 75 wt. % of the total ink formulation. Where the ink composition is to be used in a xe2x80x9ccontinuousxe2x80x9d ink jet process, a propellant is not needed. The droplets are formed by a vibrating crystal and deflected by an electric field. The ink composition preferably has a resistivity of less than 10,000 ohms/cm to achieve deflection.
The above components can be mixed and dispersed uniformly by an appropriate means such as a simple impeller within a vessel or a roll mill to obtain the ink composition of the present invention.
The ink formulations of the present invention have a viscosity in the range of 1-200 cps at 25 C, preferably 1-100 cps and most preferably between 1-25 cps to allow use within conventional ink jet printers. Where the optional binders have a viscosity much higher than 50 cps, they are diluted with a low viscosity carrier such as a plasticizer or organic solvent (alcohols or ketones).
The jet inks of the present invention adhere well to various substrates such as coated and uncoated paper, wood and plastics and show no removal or peeling off from the surface caused by stress or strain with the deformation of the substrate.
The scented printed articles of the present invention include a substrate with an absorptive surface with a fragrant image and/or indicia printed thereon by ink jet printing. The image and indicia comprise a fragrant oil and a coloring agent as defined above. The coloring agent is bound to the absorptive surface of the substrate by a binder. The binder can vary significantly in composition depending on whether it is incorporated within the substrate, whether it is incorporated within the image/indicia, whether it is incorporated within both the substrate and the image/indicia or whether it is cured in place. Where the image/indicia contains a binder cured in place, it is preferably cured by a cationic curing mechanism.
Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. The following preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever. All publications and patents cited above and below are hereby incorporated by reference.
In the foregoing and in the following examples, all temperatures are set forth in degrees Celsius and unless otherwise indicated, all parts and percentages are by weight.

Scented jet ink and printed articles therefrom


In a screw for fastening sections to a substructure, a shank (2) is provided with a boring portion (4) and a threaded portion (5) as well as a screw head (3). The portion (6) of the shank (2) adjacent to the screw head (3) flares conically toward the screw head (3). On its underside (7) the screw head (3) is provided with projections and/or depressions. During use for fastening sections to a substructure, the section to be fastened is pressed by the conical portion (6) in screwing direction against the fexed substructure (11).

The invention relates to a screw for fastening metal and/or plastic sections or plates to a substructure, comprising a shank with a boring portion and a threaded portion as well as a drive portion for applying a driving tool.
The very act of fastening sections or plates to a substructure is problematic in that such parts must achieve a condition in which they press firmly against the substructure when fastened. These negative effects are intensified when relatively stiff sections or plates become further distorted under certain circumstances or exhibit a longitudinal twist. In this case it is usually not possible to work with a depth limiter for the driving device. Even if torque clutches are used, it is still difficult to stop the process at the precise time, since an associated torque increase occurs as soon as the screw head bears on the section to be fastened, thus stopping the driving device. Further driving movement is then stopped regardless of whether or not the metal and/or plastic section or plate to be fastened continues to bear on the substructure.
The object of the present invention was therefore to provide a screw of the type mentioned in the introduction, in the use of which the section or plate to be fastened bears snugly on the substructure in the finally set condition.
According to the invention, this is achieved by the fact that the portion of the shank adjacent to the drive portion flares conically toward the drive portion, and that the diameter of the end of the conical portion of the shank close to the drive portion is larger than the diameter of the borehole receiving the screw in the section to be fastened and thus is also larger than the boring diameter of the boring portion.
By virtue of these features according to the invention, the metal and/or plastic section to be fastened is subjected to initial tension directed toward the substructure and thus is pressed thereagainst as soon as the screw has been driven in by one or more rotations. Because of the associated friction in the borehole and of the conical shape, the conical portion of the shank adjacent to the screw head exerts a force in the screwing direction on the section to be fastened.
It then becomes a simple matter to adjust an appropriate torque clutch such that it disengages only at appropriately high torque. By that time, however, the section to be fastened has already been pressed snugly against the substructure by the action of the conical portion, and so all that remains is for the driving tool to be stopped as soon as the appropriate torque is reached.
The action of the conical portion on the borehole wall also produces extremely good locking against reverse rotation. The surface of the conical portion is for practical purposes disposed in a snug-fitting seat in the borehole wall. Furthermore, in the particular case of portions that have become distorted or twisted in the process, said portions have a tendency to return to their initial condition. Thereby an additional resilient load is always exerted on the screw, intensifying the locking effect against reverse rotation, especially in view of the action of the conical portion.
It is intuitively obvious that the beginning of the conical portion must extend from the shank or from an unthreaded portion of the shank, because this conical portion, while following the shank, must be inserted easily into the borehole in the section to be fastened. Thereafter, however, it is necessary that the conical portion engage as rapidly and effectively as possible with the borehole wall, so that thereby it can apply the axial initial tension optimally. In this way the tightening torque and therefore the axial initial tension are exerted on the section to be fastened as soon as the screw has been driven in a relatively short distance, before the process of driving the screw is fully accomplished.
Another advantage of the conical portion is that optimum fastening to a substructure is possible even if said substructure comprises a thin metal sheet or other thin materials. Since the conical portion for practical purposes represents the agency which initiates an associated torque increase, stripping of the thread in the substructure cannot occur.
From DE-OS 2157212 there is already known a screw in which a conical shank portion is provided at the head end of the shank to form a thicker region in order thereby to provide the shank with reinforcement to compensate for a drive slot for a screwdriver. Furthermore, incisions are provided on the underside of the head of the known screw in order to cut a recess into the workpiece and in this way to countersink the screw head in the workpiece.
From DE-OS 2238191 there is also known a fastening means which always comprises a screw and nut. The screw is drawn into a borehole by tightening the nut, and therefore is not itself rotated. In this case the conical portion of the screw is dimensioned such that the frictional force developed by tightening the nut prevents rotation of the shank in the hole. Even if the driving tool is designed to stop at a specified torque, it could not be stopped by such friction.
In another screw known from DE 4019157 C1, a shaped portion is provided in the region of the screw head. This portion engages in the material of the substructure in order to cause a sudden large increase in driving torque of the screw immediately upon contact with the substructure. This effect is desired for screws to be driven into a substructure with poor pull-out resistance, such as gas-formed concrete. Such an effect is not desired in the use of a screw in the manner according to the invention, nor is a shaped portion of this type employed. Instead, the increasing friction between a conical portion and the borehole is utilized to stop a driving tool by torque-dependent effect.
In another proposal according to the invention, the conical portion of the shank extends directly to the drive portion or to the underside of the drive portion formed as the screw head. This ensures that the borehole will be steadily widened until the screw is finally set. Thereby there is also achieved a steadily increasing torque, which can be sensed by a driving tool with an adjustable stopping reaction.
In this regard it is also important to note that torque-activated stopping must take place with great precision, since the engagement of the thread in the substructure can be damaged under certain circumstances, thus negating the fastening effect, if driving is stopped too late.
It can also be advantageous if the diameter of the end of the conical portion of the shank close to the drive portion is larger than the outside diameter of the threaded portion on the shank. Since the screw is provided with a boring portion and thus itself creates the through-hole in the section to be fastened and also the hole in the substructure, naturally the threaded portion is also driven through the section to be fastened. Thus a corresponding thread is cut first of all in the borehole of the section or plate to be fastened, while the axial initial tensions will be developed by the conical portion in the threaded borehole of the section to be fastened. For practical purposes, therefore, the formed thread turns are compressed again or pressed flat by the conical portion, and thereby the friction between the conical portion and the borehole wall is smaller at least in the first two rotations than if the borehole wall had been smooth.
In the very cases in which the screw must be set at an exact depth, or in other words a drive portion formed as a screw head must always bear exactly on the surface of the section or plate to be fastened, the drive portion formed as the screw head can be additionally provided on its underside with projections and/or depressions. It is then possible to adjust the torque clutch of a driving tool to disengage not as soon as the conical portion exerts an effect, but only when an appropriately large torque increase is caused suddenly by the projections and/or depressions provided on the underside of the screw head, or in other words when the screw head makes full surface contact with the section or plate to be fastened. Because of the previous action of the conical portion, the section or plate to be fastened has already been pressed snugly against the substructure, and so all that remains is for the driving tool to be stopped by an appropriately massive torque increase.