CA2442429A1 - Method and apparatus for ink jet printing - Google Patents

Abstract

Ink jet printing is provided on large area substrates such as wide width textile webs. The printheads are driven by linear servo motors (633) across a bridge (630) that extends across the substrate. The timing of the jetting of the ink is coordinated with the motion of the printheads (640, 641), so that the heads can be rapidly moved and the ink can be jetted while the printhead s are accelerating or decelerating as they move on the bridge. Preferably, ultraviolet (UV) light curable ink is jetted and first partially cured with UV light (645, 646) and then subjected to heating to more completely reduce uncured monomers of the ink on the substrate. Preferably, the heat is applie d by contacting the substrate with a heated plate (661, 662). Ink jet printing is provided using ultraviolet (UV) light curable or other curable compositio n or stable or other printable substance. In certain embodiments the UV ink ha s a dye-component therein. The ink is jetted onto a substrate, the composition is cured, then heated to set the dye. Sublimation dye-based UV ink printing onto polyester is preferred. A release layer of protective material (702, 70 4) such as a TEFLON film or sheet, covers a substrate support (705, 706). A porous substrate to be printed, such as a textile material (711), is support ed on or above the support. Ink is jetted onto the substrate, with some of the ink passing through pores in the substrate and landing on the protective material. UV curable ink is preferably used and is exposed by UV light from a UV light curing head, which solidifies the ink on the substrate. The UV curi ng light has a long enough focal length to focus on the surface of the substrat e and also, where it passes through pores in the substrate, on ink on the protective material, thereby solidifying the ink on the protective material. When the substrate is removed from the support, the solidified ink on the protective material may be wiped from the protective material. The protectiv e material may be a coating on the support over which the substrate slides or a belt that moves with the substrate. A textile substrate may be preconditione d by singeing or shaving to remove fuzz from the fabric that could clog the printheads. A printhead cleaning station is also provided.

Description

METHOD AND APPARATUS FOR INK .)ET PRINTING
This is a continuation-in-part of U.S. Application Serial No. 09/932,427.
filed August 17, 2001, which is a continuation-in-part of U.S. Patent Application Serial No. 09/824,517, filed April 2, 2001, which is a continuation-in-part of U.S. Patent Application Serial No. 09/823,268, filed March 30, 2001.
This application is also a continuation-in-part of provisional U.S. Patent Applications Serial No. 60/327,622, filed October 5, 2001, and Serial No. 60/333.319, filed November 26, 2001, both hereby expressly incorporated by reference herein.
This application is also related to U.S. patent applications filed March 30, 2001 and entitled "Method and Apparatus for Printing on Rigid Panels and Other Contoured or Textured Surfaces", Serial No. 09/822,795 and "Printing and Quilting Method and Apparatus", Serial No. 09/822,794, each commonly owned with the present application and each hereby expressly incorporated herein by reference.
This application is also related to U.S. Patent Application Serial No.
09/390,571, filed September 3, 1999 and of International Application Serial No. PCT/US00/24226, filed September 1, 2000, of which LLS.
Application Serial Nos. 09/932,427 , 09/824,517 and 09/823,268 are continuations in part, which are commonly owned with the present application and are each hereby expressly incorporated herein by reference.
Field of the Invention:
The present invention relates to inkjet printing, and particularly useful for ink jet printing onto textiles, onto wide web, large panel and other extended area substrates, and onto other substrates on a high speed and commercial scale.
I3acktround of the Invention Needs have arisen for the printing of large banners, flags and signs in quantities that are not economical for many conventional printing processes. Proposals have been made to print such products from electronic source tiles that can be processed directly on the printing press or printing system, rather than through steps such as film image-setting and plate-making. One such process is ink-jet printing.
These processes have been attempted on surfaces such as vinyl, hut printing with success onto textile surfaces has been even more limited.
Such processes have been slow and lack reliability. The clogging of print heads in ink jet printing has been too frequent for use in wide width and large area substrates, and the processes used have not produced acceptable printing on textile materials.
The printing of substrates that are more than several feet, or a meter, wide, referred to as the special category of "wide width" printing, into which category the printing of signs and banners, office partitions , mattress ticking and most other quiltahle materials would fall, is beyond manyof the limitations of conventional printings methods. A number of technical problems exist that have deterred the development of the printings of wide fabrics such as mattress covers, upholstery, automobile seat cover fabrics, office partitions and other wide wICItIt SLIbSTraTeS.
Wide width products are frequently printed in relativelysmall quantities.
Traditional printing typically involves the creation of a plate, a mat, a screen. or some other permanent or at least tangible, physical image from which ink is transferred to the object being printed. Such images contribute a relatively high set up cost fllat IS UItIY economical where the number of identical copies of the product is large. At the other extreme, office printers, for example, print a single copy or a small number of copies of a given document or other item, and are currently of the type that uses no permanent, physical image transfer element, but which rather prints fnnn a software or program controlled electronic image, which can be changed from produc«o product. Such printing is sometimes referred to as direct digital printing, although the process need not necessarily be literally "digital" in the sense of a set ctf stored discrete numerical values. Lnk jet printers are a common type of such direct digital printers in use today.
Ink jet printers print by projecting drops of ink on demand onto a substrate from one or more nozzles on one or more print heads. Office printers and other narrow width inkjet printers usually dispense water based or other solvent based inks onto the substrate by heating the ink and exploding bubbles of the ink out of the nozzles. These printers are often called bubblejet printers. The ink from such printers dries by evaporation of a solvent. Sometimes additional heat is used to evaporate the solvent and dry the ink. Printing onto wide width substrates with bubble type inkjet printers, or inkjet printers that use high temperature techniques to propel the ink, suffer from limited printhead life or high mean time between failures that require downtime and servicing.
The heat used to expel the ink and to cause the evaporation of the solvents, evaporation that occurs during printhead downtime, and the therntal cycling of the heads, causes these print heads to clog or otherwise tail after as little as 20 milliliters of ink is dispensed. Office printers are, for example, often designed so that the print head is replaced every time a reservoir of ink is replenished. For this reason, for larger scale ink jet printing processes, such as wide width printing= of Films used for outdoor advertising, signa ~e and architeemral applications, print heads that use mechanical ink propulsion techniques are more common. Such mechanical print heads include piezo or piezo-crystal print heads, which convert electrical energy into infra-crystal vibrations that cause drops of ink to be ejected from print head nozzles.
1'iezo print heads are particularly useful fc>r applying inks that dry by polymerization which can be brought about after the ink leaves the print head and is deposited onto the substrate, usually by exposure to some Form of energy medium such as electromagnetic or particle radiation. Inks have been formulated for ink jet printing that can be polymerized by exposure to a radiation curing source such as a focused beam of ultra violet light (UV) cn' high energy beams of electrons (EB). The inks generally incorporate stabilizers which prevent premature curing due to low levels of light exposure. Therefore, the inks usually require exposure to some threshold level of energy to initiate a polymerization reaction. Unless exposed to such threshold energy levels, such inks do not polymerize and remain stable, with a low tendency to dry in the nozzles or elsewhere unless cured by adequate exposure to the energy medium.
Solvent based inks are primarily cured by evaporation of the solvents. Some solvent based inks can be cured only by air drying, while others require the application of heat to enhance the evaporation of the solvent. In some cases, heat will facilitate a chemical change or polymerization of the ink along with an evaporation of a solvent. Polymerizable inks include monomers and oligomers that polymerize, and other _3_ additives. UV curable inks polymerize when exposed to UV light at or above the threshold enemy level. These UV curable ink formulations include photo-initiators which absorb light and thereby produce free radicals or canons which induce cross-linking between the nnsaturation sites of the monomers, oligomers and polymers, as well as other additive components. Electron beam-cured inks do not require photo-inhibitors because the electrons are able to directly initiate cross-linkin«.
Heat or air curable inks that are organic solvent based or water based inks often do not have as high a color intensity as UV curable or other polymerizable inks because the pigments or dyes that produce the color are somewhat diluted by the solvent. Furthermore, organic solvents can produce an occupational hazard, requiring costly measures be taken to minimize contact of the evaporating solvents by workers and to minimize other risks such as the risks of fire. Solvent based inks, whether applied with heat or not, tend to dry out and eventually clog ink jet nozzles. In addition, solvent based inks set by forming a chemical bond with the substrate, and accordingly, their formulation is substrate material dependent.
As a result, the selemiun of solvent based ink varies from fabric to fabric. Specific ink compositions are paired with specific fabric compositions to improve the fastness of the ink to the fabric, which results from chemical or electrostatic bonds formed between the ink and the fabric. Where the selected ink composition does not react or otherwise has an affinity with the surface of the particular fabric, the ink merely maintains a physical contact with the fabric surFa ce and typically is easily removed by water, another solvent or abrasion. With UV and other radiant beam-curable inks such as electron beam-cured inks, the bonding between the ink and fabric is primarily mechanical and not limited to specific combinations of ink and fabric.
Polymerizable inks, particularly those cured upon exposure to a radiation or energy medium, are difficult to cure on three dimensional substrates such as the surface of a textile. While UV curable inks are capable of providing hlghel' color intensity and do not present the hazards that many solvent based inks present and can avoid nozzle clo~~ging, printing with UV curable ink onto textile fabric presents other problems that have not been solved in the prior art. Tu cure UV ink, for example, it nmst be possible to precisely focus a UV curing light onto the ink. UV ink, when jetted onto fabric, particularly onto highly textured fabric, is distributed at various depths over the texture of the fabric surface. Furthermore, the ink tends to soak into or wick into the fabric. As a result, the ink is present at various depths on the fabric, so that some of the ink at depths above or below the local plane of the UV curing light evade the light needed to cause a total cure of the ink. In order m cure, UV ink must be exposed to UV li~.:ht at an energy level above a curing threshold. However, increasing the intensity of the curing light beyond certain levels in order to enhance cure of the ink can burn, scorch or otherwise hove destructive effects on the deposited ink ur the fabric.
Furthermore, ink jet printing can be carried out with different ink color dots applied in a side-by_side pattern or in a dot-on-dot (or drop-on-drop) pattern, with the dot-on-dot method being capable of producing a higher color density, but the higher density dot-cm-dot pattern is even more difficult to cure when the cure is by UV light.
In addition, UV ink can he applied quickly to reduce wicking and UV ink can be developed to allow minimized wicking. Some wicking, however, can help to remove artifacts.
Further, many inks developed to eliminate wickin~~ leave a stiff paint-like layer on the surface of the fabric, giving the fabric a stiff Feel or "bad hand". Therefore, to reduce the UV curio ~ problem by eliminating wicking is not always desirable.
UV curing of jetted ink on fabric has been plagued by a limited cure depth that is determined by the depth of field of the focused curin~~ UV light. When UV curable ink is jetted onto fabric, UV light may be ineffective to cure a sufficient portion of the ink. A large uncured portion of the deposited ink can cause movement of the ink or the loss of the ink over time, resulting in deterioration of the printed images. Even if a sufficient portion of the ink is cured to avoid visibly detectable effects, uncured ink at some level has the possibility of producin~~ symptoms in some persons who contact the printed fabric. The amount of uncured monomers or ink components that can cause problems by inhalation or direct skin contact has not been officially determined, hut standards exist tordetermining limits torcomponents of packaging material ingested with tool.
For example, if more than approximately 100 parts per million (PPM) of ink from packaging material is present in food, some persons who are sensitive to the uncured monomers may suffer reactions and others may develop sensitivities to the material. Such criteria assumes that L square inch of packaging material makes contact with ten grams of food. Thus, to interpret this criteria, it is assumed that each PPM of ink component in packaged food is equivalent to 15.5 mil ligrams of ink component mi gating out of each square meter of packaging material into the food. While this does not provide an exact measure of the amount of uncured ink components that might be harmful to humans, it suggests that approximately 10% of uncured ink components on items of clothing, mattress covers or other tabl'ICS with Whlch persons may be in contact for extended periods of time, may be unacceptable.
For the reasons stated above, UV curable inks hove not been successfully used to print onm fabric where a high degree of cure is required. Heat curable or other solvent based inks that dry by evaporation can be cured on fabric. As a result, the inkjet printing of solvent based inks and heat curable or air dryable solvent based ink has been the primary process used to print on fabric. Accordingly, the advantages of UV or other radiation curable ink jet printing have not been available for printing onto fabric.
UV inks, other polymerizable inks and other stable inks are typically those that reside on the surface of the substrate. The color components of the inks are in the form of pigments suspended in a polymer or other curable matrix. When the printed substrate is washed or exposed to weather or wear, the ink coating usually fades or otherwise degrades. Tnks containing dyes, on the other hand, provide color fastness because the dye dissipates into and becomes chemically or mechanically hooded to the fibers of the substrate. Such dye-based inks are particularly useful in printing on polyester substrates, where sublimation dyes effectively bond to the polyester fibers. But because such inks employing dyes as the color component have traditionally required a solvent to suspend and carry the dye to the substrate, dye-based inks have resulted in "drop-spread", wicking of the ink, or blurring of the images that are being printed. As a result, the need to reduce this drop-spread with dye-haled inks has necessitated the use of' transfer processes rather than direct digital printing.
Furthermore, in the ink jet printing of textiles, specifically those made of porous materials or open weave fabrics, the jetted ink passes through holes in the substrate and deposits onto the substrate support.
Traditionally, an absorbent blotter-like layer is placed under the substrate to collect the excess ink. The handling and disposal of the ink carrying layer is messy and inconvenient.
There exists a need in printing of patterns onto mattress ticking and mattress cover quilts, as well as onto other types of fabrics, for a process to hrin« about an effective cure of ink compositions containin~~ UV
curable inks and to render practical the printings with UV curable inks onto fabric for clog tree ink-jet pr inting with stable inks that are completely curable, result in color fast images, with a minimum of drop spread.
Additionally, a better way is needed for handling excess ink that passes through porous textiles in an ink-jet printing process.

Summary of the Invention Objectives of the present invention include providing ink-jet printing with stable inks, providing for the complete curing of such inks, and providing fr>r producing color fast images with such printing, particularly with a minimum of drop spread. A further and more particular objective of the invention is to provide for the inkjet printing of dye-based inks.
One objective of the present invention is to provide an effective method and apparatus for wide width direct digital printing, and for printing onto textiles. Another objective of the invention is to effectively apply a stable curable ink onto a textile or other substrate and to effectively cure the ink on the substrate with UV or other energy, a chemical curing agent or other curing medium, and particularly doing so using ink jet printing.
A further objective of the invention is to successfully apply and effectively cure ink jetted onto textiles and other substrates in a reliable manner without a tendency of the nozzles of the heads to frequently clog=. Particularly, it is an objective of the invention to print onto textile fabrics and wide width substrates with a piezo or other mechanical or electro-mechanical print head.
Another objective of the invention is to provide fur the printing onto textiles and other textured or wide width substrates using a printable substance that remains stable until deposited onto the surface of the substrate, and particularly by curing the substance a sufficiently short time from when the substance contacts the substrate to freeze the substance and prevent the spreading thereof. It is a further objective of the invention to do so while providing color fastness or other advantages of dye-based inks.
A particular objective is to provide such a process for printing with UV ink or other inks that are curable by exposure to iml>ingin~~ energy. A particular objective of the invention is to provide for the effective curing of UV inks jetted unto textile or fabric by reducing uncured monomers and other extractable non-solvent polymerization reactants, including reactant byproducts, or components of the ink, to a level most likely to be tolerable by or acceptable to persons contacting the printed substrates.
Another objective of the invention is to acc<nnmudate ink that isjetted through a porous or open weave substrate in a neat and efficient manner.
According to the principles of the present invention, a stable ink is digitally printed onto fabric and setting of the ink is initiated after the ink is deposited unto the substrate.
By a ''stable ink" is meant one that will not Beduin to cure, thicken or otherwise change properties in a way that will adversely affect the ability to apply the ink to the substrate, unless and until such ink is exposed to a curing medium that is otherwise absent from its environment. Inks that begin to set or which thicken upon evaporation of a solvent are not stable as herein defined. Inks that begin to polymerize before being exposed to UV light from a particular light source or to chemical agents that are provided to contact the inks after being applied to a substrate are also not considered stable.
In the preferred embodiment, stable UV ink monomers are deposited onto the substrate and polymerization of the ink is initiated by exposure to an impinged energy beam, such as UV, EB or other such energy beam. In accordance with certain aspects of the invention, the UV
exposed or otherwise polymerization initiated ink is thereafter subjected to heat to reduce the content in the ink of tlnpulynlerlZed pOlylllerlZable reactants and other extractable components of the ink to low levels that are likely to be tolerable or otherwise acceptable to persons contacting the fabric.

According to embodiments of the invention, stable dye components can are added to the otherwise polymerizable or stable ink or other printable colorant or substance to form a stable composition. The composition is digitally printed onto the substrate, whereupon the dye component is brought into contact with fiber surfaces in the fabric to chemically bond or form an affinity with those surfaces. Polymerization of the UV or other curable ink component is initiated by exposure to an impinged energy beam, such as UV, EB or other such energy beam. This exposure is preferably carried out upon contact of the substrate by the substance or immediately after. This effects at least a surface cure of the UV or other curable ink component, freezing the dots on the substrate surface and preventing clot spread, but generally has little effect on the dye component.
Then the partially polymerized or cured printed subst.mce is thereafter subjected to heat to complete ch emicul bonding of the dye or to finalize formation of its affinity to the fiber surfaces, and to reduce the unpolymerized polymerizable reactants and otherextractable components of the UV or other curable component. In liarticular.
the invention provides for an ink COIIIpoSltloll WI11CI7 (:OIItaIIIS, in combination with the UV ink ur other inks curable by exposure to impinging ener~~y, one or more. dyes which are both reactive or have an afttnUy to some or all of the fiber surfaces of the fabric and are compatible with the UV or other curable ink. The UV inks or other inks curable by exposure to impinging energy are comprised of a polymerizable portion and at least one pigment, suspended in the polymerizable portion.
The ink composition incorporates a separate dye component which is combined with the UV or other impinging energy curable ink base. The base may or may not also contain pigment. The dye component of such ink compositions may be selected from the ~~mup including, but not limited to, dispersion dyes, reactive dyes, acid dyes, basic dyes, metallized dyes, naphthul dyes and dyes that do not require a post-treatment to either set the dye or to develop the color. Dispersion dyes are widely used for dyeing most manufactured fibers, including particularly the fibers of polyester and other synthetic textiles. Reactive dyes are anionic dyes which react with hydroxyl groups in cellulosefibers in th epresenceof alkali. Acid dyes are used on wool and other animal fibers, as well as certain manufactured fibers such as nylon. Basic dyes are positive-ion-carrying dyes which have a direct affinity for wool and silk. These dyes may also be used on basic-dyeable acrylics, nu>dacrylics, nylons, and polyesters. Naphthol dyes are formed on the fiber by first treating the fiber with a phenolic compound in caustic solution and then applying a solution of a diazonium salt. the salt reacts with the phenolic compound to produce a colored azo compound. Generally, these dyes are used for cellulose fibers.
Dye based inks according to the present invention may also be applied to solid non-textile articles, as for example ceramic mugs and plates. Such articles are coated with acrylates or other polymeric substances to which dyes such as dispersion dyes can bond. With the invention, the traditional transfer printing process used for such articles can be replaced with direct digital printing with dye-based polymerizable ink.
In certain embodiments of the invention, a stable ink composition is jetted unto fabric and the set or curs of the ink is initiated by exposure to a chemical substance, energy or otherwise after it is ejected from the inkjet nozzles. In the preferred and illustrated embodiments, UV polymerizable ink is jetted onto the substrate where it is exposed to UV light for its cure. Preferably, a non-bubble jet print head such as a piezo-crystal or other mechanical ink ejection transducer is used to jet the ink. Heat may be applied to the piezo-crystal or other mechanical ink injection transducer during operation, but generally only to the extent necessary for ink viscosity reduction. With or following the exposure to the UV light, the printed fabric is subjected to heat, either in the form of a heated air stream, a heated platen or other heat source, which either extends the UV light initiated _7_ curing process, drives off uncured components of the ink, or both. Any dye component suspended in the ink is also activated and set by the heat. With a subllmatlon dye component the suspended dye particles are believed to sublime into molecule sized particles which are hi~=hly reflective and produce intense color. These molecules disperse into cavities in the substrate, into pores on the textile fiber surface, or elsewhere in the cured matrix of the polymerizable ink component, where they are fixed upon cooling.
Typically one or more sets of tour print heads are provided on a carriage, with each of the Four heads of each set configured to scan the substrate sequentially to deposit each of four colors of a CMYK color set.
In a preferred embodiment, two sets of four print heads each are configured so that each set prints the same tour colors in a two printhead wide strip, or alternatively, the sets are configured and controlled to print over the same area with each of eight colors.
More particul;u-ly, UV curable ink is jetted onto the substrate, and the jetted ink is exposed to UV
curing light to cure the UV ink component to an extent sufficient to render the printed image substantially resistant to further wicking, which is ~~enerally about 60 to 95°lo polymerization dependin~~ on ink density.
substrate porosity and composition, and substrate wei~~ht and thickness.
Preferably, UV ligln curing heads are mounted on the carriage carrying the printheads across the substrate, one on each side of the heads, with the lights alternating during the bidirectional motion of the printheads to expose the ink innnediately after being deposited on the substrate with light from the trailing li~_ht curing head.
1'he light curing heads are directed onto the substrate to expose the ink immediately after it contacts the substrate to freeze the dots of ink and curtain the wicking of the ink into textile and other absorbent fabric. Then, the fabric hearing the partially cured jetted ink is heated with heated air in a heat ~urin;,~ oven or by contacting the substrate with a heated platen or both, at which time the UV light initiated polymerization may continue, or uncured monomers are vaporized, or both, in order to produce a printed image of UV ink that contains a reduced level of uncured monomers or other components of the ink which is likely to be tolerable by persons sensitive or potentially sensitive to such ink components. Where dye is included in the ink, the presence of heat facilitates chemical bonding or affinity formation of unreacted dye in contact with fiber surfaces in the fabric.
Preferably, the uncured components of the ink are reduced to an order of magnitude of about a gram per square meter, for example, and generally not more than about 1.555 grams per square meter of uncured monomer on the fabric substrate.
1n the preferred embodiments, linear servo motors are provided to drive the print heads, at least transversely, over the substrate. Linear motors are easier to tune, require little service, and have better acceleration and deceleration than belt or other drive systems. Such servos provide accuracy that enables printing to be carried out while the heads are accelerating or decelerating.
Progrannned compensation is made for the variable head speed by the timing of the,jetting of the ink. Thus, areas of the substrate having no printing can be skipped at high speed, ~~reatly improving the ,peed and efficiency of the print operation by minimizing the time during which the print head is not depositing ink cm the substrate.
To the extent that a dye component is included which does not bind chemically to the fiber surfaces or form an affinity, the portion of dye which does not react with the surfaces is encapsulated within the polymerized UV ink composition to minimize min ration of the dye. This encapsulation effect reduces or eliminates the need For post-treatment to remove the mobile dye from the fabric.
According to the preferred embodiment of the invention, ink isjetted onto a textile material or a highly tex«n-ed fabric such as a mattress cover ticking material, preferably prior to the quilting of the fabric into a _g_ mattress cover. The ink is_jetted at a dot density of about 180x256 dots per inch per color to about 300x300 dots per inch per color, thOllgh lower dot densities of from about 90x256 dots per inch or as low as about 90x90 dots per inch can be applied with acceptable resolution for certain applications.
Typically, four colors of a CMYK
volor palette are applied, each in drops or dots of about 75 picoliters, or approximately 80 nanograms, per drop.
utilizing a UV ink jet print head. A UV curing= light head is provided, which moves either with the print head or independent of the print head and exposes the deposited drops of UV ink with a beam of about 300 watts per linear inch, applying about 1 joule per square centimeter. Generally, UV ink will begin to cure, at least on the surface, at low levels of energy in the range of about 20 or 30 millijoules per square centimeter. However, to effect curing= in connnercial operation, higher UV intensities in the range of about 1 joule per square centimeter are desired. Provided that some minimal threshold level of energy density is achieved, which can vary based on the formulation of the ink, the energy of the. beam can be varied as a function of fabric speed relative to the light head and the sensitivity of the fabric to damage from the energy of the beam.
The fabric on which thejetted ink has been thereby partially UV cured is then passed through an oven where it is heated to about 300°F for from about 30 seconds up to about three minutes. Forced hot air may be used to apply the heat in the oven, but other heating methods such as infrared or other radiant heaters may be used. Alternatively, heated platens nary be used to heat the ink bearing material, and such platens are particularly effective in bringing the material quickly up to the 300"F
temperature. The UV energy level, oven heating temperature and oven heat time may be varied within a range of the above listed values depending on the nature of the fabric, the density, type and composition of the applied ink; and the speed of the fabric during processing relative to the UV curing light head. 'Chas, a higher ink density applied to the fabric will generally require more UV energy, higher oven heating temperature, longer oven heat time or a combination of' these variables, to effect the necessary curing on tl~e particular fabric. With dye-based inks, the temperature should be that most effective to set the dye, often over 350°F, for example, at about 385"F.
The reliability otthe printing processes may be enhanced, according to certain aspects oFthe invention, by preconditioning the substrate, such as by precoating, shoving or singeing of the surface to be printed. Such preconditioning eliminates dust and lint that could collect on the print heads and potentially contribute to clog~~ing of the nozzles.
The invention further provides an online printhead cleaning station for automatic cleaning of the printheads during the course of the printing process. Preferably, periodically during the course of the printing of an extended area substrate, the printhead carriage is traversed to the printhead cleaning station where ink is jetted from the heads to purge the nozzles and the heads are wiped of ink and foreign matter that might have.
collected on them.
The invention further provides for nn ink composition which contains, in combination with the UV
ink or other inks curable by exposure to impin~~ing energy, one or more dyes which are both reactive or hove an affinity to some or all of the fiber surfaces of the fabric :md are compatible with the UV or other curable ink.
~fhe UV inks or other inks curable I>y exposure to impinging ener~Y are comprised of a polymerizable portion and at least one pigment, suspended in the polymerizable portion.
Stable dye components can be added to the otherwise polymerizable ink to form a stable composition.
~fhe composition is digitally printed onto the substrate, whereupon the dye component is brought into contact with fiber surfaces in the fabric to chemically bond. Further, the amount of heat applied is that qeeded to cause reaction or form an affinity with those surfaces. Polymerization of the UV or other curable ink component is initiated by exposure to an impin~~ed ener~~y beam, such as UV, EB or other such energy beam. This effects at least a surface cure of the UV or other curable ink component, but generally has little effect on the dye component. Then the partially polymerized or cured ink is thereafter subjected to heat to both complete chemical bonding of the dye or finalizing formation of an affinity to the fiber sulfiaces and reduce the unpolymerized polymerizable reactants and other extractable components of the UV or other curable ink component to low levels that are likely to he tolerable or otherwise acceptable to persons contacting the fabric.
Where such dye is included in the ink, the presence of heat facilitates chemical bonding or affinity formation of unreacted dye in contact with fiber surfaces in the fabric.
Where the ink composition incorporates a separate surface of the substrate is a function of at least the dye component which is combined with the UV or other curable ink base, the dye portion of such ink compositions may be selected from dyes that are stable and are compatible with the ink anti the substrate, and are selected From the group that includes, but is not limited to, disperse dyes, reactive dyes, acid dyes, basic dyes, metallized dyes, naphthol dyes and other dyes which do not reduire a post-treatment to either set the dye or to develop the color. Disperse dyes are widely used for dyeing most manufactured fibers. Reactive dyes are anionic dyes which react with hydroxyl groups in cellulose fibers in the presence of alkali. Acid dyes are used on wool and other animal Fibers, as well as certain manufactured fibers such as nylon. Basic dyes are positive-ion-carrying dyes which have a direct affinity For wool and silk. these dyes may also be used on basic-dyeable acrylics, modacrylics, nylons, and polyestel:s. Naphthol dyes are formed on the fiber by first tre;ttin~T the fiber with a phenolic compound in caustic solution and then applying a solution of a diazonium salt. the salt reacts with the phenolic compound to produce a colored azo compound. Generally, these dyes are used for cellulose fibers.
To the extent that a dye component is included which does not bind chemically to the Fiber surfaces or Form an affinity, the portion of dye which does not react with the surfaces is encapsulated within the polymerized UV ink COIIIpOSIII()n f0 I111I11n11Ze IlllgraC1011 of the dye.
This encapsulation effect reduces or eliminates the need for post-treatment to remove the mobile dye from the fabric.
Further, the unu~unt o1' heat needed to cause reaction or form an affinity of the dye component, when included, with the fiber sul-face of the fabric is a function of at least the dye component concentration, dye chemical ColnpO51t1011, fiber composition, and fabric processing speed past or through the heat source.
Generally, the upper limits for the UV or other impinging beam of energy and oven heating temperature are those values which, when applied to the specific ink and fabric, begin to damage or otherwise adversely affect the applied ink, the underlying fabric or both.
The invention has the advantage that, for different inks and using different criteria for the desired residual amount of uncured ink components remaining on the substrate, the parameters can be varied to increase or reduce the residual amount. By increasing or decreasing the intensity of energy, or using a different Form of energy than UV, or by increasing or decreasin T the time of exposure of the ink to the energy, the amount of remaining unpolymerized non-solvent ink components can be changed.
Additionally, using higher or lower temperatures, or more or less air tlow, or greater or less heating time in the post curing oven, can change the final composition of the ink on the substrate. Care, however, should be taken that the energy curin'= or heatin~~
process does not damage the fabric or the ink.

- l0-A further advantage of the invention is that a portion of the ink composition can be included that will combine with fiber surfaces to provide coloration which is chemically bonded or has an affinity to those surfaces. Color or wash fastness due to chemical reaction or affinity formation of the dye to fiber surfaces over at least a portion of the printed fabric is accomplished while maintaining the advantage of mechanical bonding of the UV ink component onto other portions of the fiber.
The invention makes it possible to print images on fabric with UV curable ink by providing effective curing of the ink, leaving less than a nominal 1.5 grams of uncured monomers per sduare meter of printed m;uerial and usual 1y leaving only about 0. I 5 grams per sduare meter of uncured monomers. Thus, the invention provides the benefits of using UV curable ink over water and solvent based inks, including the advantages of high color saturation potential, low potential sensitivity or toxicity, and without clogging the~jet nozzles and enabling the use of piezo or other high longevity print heads. Furthermore, the encapsulation effect provided by the cured UV ink substantially or completely prevents migration of non-binding dye, if included, onto other sections of the fabric, or onto other fabrics as in the case of washing the printed fabric with other items.
Furthermore, the ability to print on wide width fabrics with polymerizable inks, which do not form chemical bonds with the substrates, and therefore are not material dependent, provides an advantage, particularly with Fabrics such as mattress covers and other furniture and bedding products.
The invention also makes possible the digital printing of sharp, clear images with dye-based inks on surfaces where the spreading of the dots has heretofore occurred.
In accordance with other principles of the invention, ink that passes tln'ough a porous or open weave substrate is collected and removed without contaminating the substrate. Where a substrate, for example, is a texti 1e sheet or is in the form of a continuous roll-to-roll web that is fed through a printing station at, a carriage carries an ink jet printhead array across the substrate and jets ink onto the substrate. Where the substrate is porous or of an open weave, ink passes tluough the substrate. For such a substrate, a layer of protective film, preferably of the type to which the ink does not strongly adhere, underlies the substrate. A sheet of TEFLON
or other non-stick material, may, for example, be used to cover a table on which the substrate is supported.
Preferably, the substrate is maintained in tension or otherwise supported out of contact with au underlying surface, and a surface of a table in the re~~ion under the printhead is provided with the layer of protective film.
lnk deposited onto the film may be partially cured, particularly where it is UV curable ink and UV light that is provided to cure ink on the substrate also partially impinges on the protective film. Where the substrate contacts the underlying surface, the film is preferably such that the adhesion between the jetted and partially cured ink and the layer of protective film is only great enough to prevent the ink from being wiped from its surface by the substrate. In any event, this adhesion is preferably such that ink can be easily removed by wiping or washin from the protective film layer.
The collection of lnk that is jetted from a printhea d through a porous substrate is useful for all types of jetted ink, but particularly where the ink is UV curable ink. In such a case, a primary UV light curing source exposes the ink that has been jetted onto the substrate. Preferably, the curing light is mounted on or near the carriage to cure the ink immediately after it reaches the subsu'ate so that the dots of ink are frozen before they have a chance to flow into the substrate or spread. As some ink passes through holes in the substrate and deposits onto the underlying release layer, UV pi ~ht from the prinuu-y source exposes the ink on the layer may I>e directed to at least partially cure the ink deposited onto the protective film. In this case, the source preferably emits essentially parallel UV light or light having a focal length sufficiently long that the li~~ht penetrates the substrate at the holes and cures ink on the underlying layer. Another UV
curing source may alternatively be provided or provided in addition to the UV source on the primary source forcurin~~ ink on the release layer. The layer may be fixed so that the substrate moves parallel to it or may be in the form of a belt that moves with the substrate. The ink on the release layer, which is at least partially cured, may be wiped or vacuumed From the layer.
These and other objects of the present invention will be more readily apparent from the following detailed description of the preferred embodiments of the invention.
Brief Description of the Drawins~
Fig. 1 is a diagrammatic perspective view of a one embodiment of a web-fed mattress cover printing and quilting machine embodying principles of the present invention.
Fig. 2 is a perspective view of an ink jet printing machine embodying principles of the present invention.
Fig. 3 is cross-sectional view of the printing machine of Fig. 2.
Fig. 4 is a perspective. view of a portion of the machine of Figs. 2 and 3.
Fig. 5 is a top view of the portion of the machine illustrated in Fig. 4.
Fig. 5A is a perspective view of a portion of Fig. ~.
Figs. 6 and 6A-6D are prints of display screens of the operator terminal and information bridge of the machine of Fig. 1.
Figs.7A-7C are diagrams illustratin ~ alternative embodiments of the feature of the invention by which ink jetted through a porous substrate is acconnnodated.
Detailed Description of the Preferred Embodiment Fig. 1 illustrates a duiltin~~ machine l0 having a stationary frame 11 with a longitudinal extent represented by an arrow 12 and a transverse extent represented by an arrow 13.
The machine 10 has a front end 14 into which is advanced a web t5 of ticking or facing material from a supply roll 16 rotatably mounted to the frame l 1. A roll of backing nnuerial l7 and one or more rolls of filler material 18 are also supplied in web form on rolls also rotatably mounted to the frame I 1. The webs are directed around a plurality of rollers (not shown) onto a conveyor or conveyor system 20, each at various points along the conveyor 20. The conveyor system 20 preferably includes . pair of opposed pin teetering belt sets 21 which extend through the machine l0 and onto which the outer layer 15 is fed at the front end 14 of the machine l0. The belt sets 21 retain the web l5 in a precisely known longitudinal position thereon as the belt sets 21 carry the web IS throu~~h the longitudinal extent of the machine 10, preferably with an accuracy of 0 to 1/4 inch. The longitudinal movement of the belts 21 is controlled by a conveyor drive 22. The conveyor 20 may take alternative forms including, but not limited to, opposed cog belt side securements, longitudinally moveable positive side clamps that engage and tension the material of the web 15 or other securin~~ structure for holding the facing Illatel'I;tI web IS fixed relative to the Conveyor 20.
Along the conveyor 2U are provided three stations, including an inkjet printing station 25, a UV light curing station 24, a heated drying station 26, a duiltina station 27 and a panel cutting station 28. The backing material l7 and filler material 18 are brought into contact with the top layer IS between the drying station 26 and the quilting station 27 to form a multi-layered material 29 for quilting at the quilting station 27. Preferably, - l2-the layers 17,18 are not engaged by the belt sets 2 L of the conveyor 20, but rather, are brought into contact with the bottom of the web 15 upstream of the duiltin;~~ station 27 to extend beneath the web 15 through the quilting station 27 and between a pair of pinch rollers 44 at the downstream end of the quilting= station 27. 1'he rollers 44 operate in synchronism with the belt sets 21 and pull the webs 17,18 through the machine 10 with the web I5.
The printing station 2~ includes one or Inure ink jet printing heads 30 that are transvel:sely moveable across the frame 1 1 and may also be longitudinally moveable on the frame 11 under the power of a transverse drive 3l and an optional lun'~itudinal drive 32. t~Iternatively, the head 30 nuiy extend across the width of the web 15 and be configured to print an entire transverse line of points simultaneously onto the web 15.
The ink jet printing head 30 is configured to jet UV ink at 75 picoliters, or approximately 80 nanograms, per drop, and to do so for each of four colors according to a CMYK
color pallette. Preferably, the printing head 30 does not undergo a heating step durinU operation. A
mechanical or electro-mechanical print head such as a piezo print head is preferred. The dots are preferably dispensed at a resolution of about 180 dots per inch by about 256 dots per inch. The resolution may be higher or lower as desired, hut the 180x256 resolution is preferred. If desirable for finer inuy~es or greater color saturation, 300x300 dots per inch is preferable. The drops of the different colors can be side-by-side or dot-on-dot. Dot-on-dot (sometimes referred to as drop-on-drop) produces higher density.
The print head 30 is provided with controls that allow for the selective operation of the head 30 to selectively print two-dimensional designs 34 of one or more colors onto the top layer web 15. The drive 22 for the conveyor 20, the drives 31,32 for the print head 30 and the operation of the print head 30 are program controlled to print patterns at known locations un the web l5 by .1 controller 35, which includes a memory 36 fur storing programmed patterns, machine control programs and real time data regarding the nature and longitudinal and transverse location of printed desi~=ns on the web 15 and the relative longitudinal position of the web 15 in the machine 10.
The UV curing station 24 includes a UV light curing head 23 that may move with the print head 30 or, as is illustrated, move independently of the print head 30. The UV light curing head 23 is configured to sharply focus a narrow longitudinally extending beam of UV light onto the printed surface of the fabric. The head 23 is provided with a transverse drive 19 which is controlled to transversely scan the printed sulfiace of the fabric to move the light beam across the fabric. Preferably, the head 23 is intelligently controlled by the control ler 3~ to selectively operate and quickly move across areas having no printing and to scan only the printed images with UV light at a rate sufficiently slow to UV cure the ink, thereby avoiding wasting time and UV
energy scannin~~ unprinted areas. If the head 23 is included in the printing station 25 and is coupled to move with the print head 30, UV curing light can be used Ill Sylllhl'OnISlll Wlth the dispensing of the ink innnediately Following the dispensing of the ink.
The UV curing station 24, in the illustrated embodiment, is located innnediately downstream of the printing station 25 so that the fabric, innnediately following printing, is subjected to a UV light cure. In theory, one photon of UV light is required to cure one Free radical of ink monomer so as to set the ink. In practice, one joule of UV light energy is supplied by the UV ~urin~~ head 23 per square centimeter of printed surface area.
This is achieved by sweeping a UV beam across the printed area of the fabric at a power of 300 watts per linear inch of beam width and exposing the surface I'ur a time sufficient to deliver the energy at the desired density.
Alternatively, if fabric thickness and opacity are nut tc>o high, curing li~~ht can be projected from both sides of the fabric to enhance the curing of the UV ink. Using power much higher can result in the burning or even COIllbllvtl011 Of the fabric, so UV power has an upper practical limit.
The heat curing or dryings station 26 is fixed to the frame 1 l, preferably innnediately downstream of the UV light curing station. With sufficient UV cure to stabilize the ink such that the printed image is substantially resistant to further wicking, the ink wi II be sufficiently color-fast so as to permit the dryin~a station to be off-line, or downstream of the cluiltin~= statiim 27. In embodiments in which . dye component is included in the ink composition, the dye will have either reacted or formed an affinity with certain fiber surfaces, or will have become substantially or completely encapsulated within the cured UV in component. When on-line, the drying station should extend sufficiently along the len~_th of fabric to adequately cure the printed ink at the rate that the fabric is printed. Heat cure at the oven iar dryings station 26 maintains the temperature ut the ink un the fabric at about 300°F for up to three minutes. I-leatin ~ of from 30 seconds to 3 minutes is the anticipated acceptable range. Heutin~~= by forced hot air is preferred, although other heat sources, such as infrared heaters, can be used as long as they adequately penetrate the fabric to the depth of the ink.
The exact percentage of tolerable uncured monomers varies from ink to ink and product to product.
Generally, it is thought that uncured monomers of UV curable ink should be reduced to below about 0.1%, or 1000 PPM. In the preferred embodiment of the invention, uncured monomers of UV
curable ink are reduced to less than 100 PPM, an<l preferably to about l0 PPM. As explained above, each 1 PPM is equivalent to about 15.5 milligrams extractables per sduare meter of printed material. As used herein, the percentage or portion of remaining uncured monomers refers to the mass of extractable material that can be removed from a given sample of cured ink by immersing the cured ink sample in an aggressive solvent such as toluene, and measuring the amount of material in the solvent that is removed from the ink by the solvent.
The measurements are made with a gas chromatograph with a mass detector. 1n the preferred embodiment of the invention. the measured amount of material removed from a given sample of the ink is less than 1.5 grams extractables per sduare meter of printed material. Measurements of him/her than 100 PPM or 1.5 grams extr;tctables per sduare meter of printed material are undesirable. Measurements of 10 PI'M are preferred.
In certain embodiments, an ink composition comprising a UV ink component and a dye rnmpunenl are formulated in a manner which ~~enerates. compatible, shelf-stable composition. The relative concentration ranges of UV ink component to dye component in such compositions will vary with the nature of the fabric being printed, and the respective physical characteristics of the UV ink and dye components. Nun-limiting physical characteristics of the UV ink and dye which are evaluated in connection with enhancing compatibility of the UV ink component with the dye component include polarity, viscosity, and pH. The dye and UV ink would be selected so that no reaction occurs or can be expected to occur between these ink components ur with any other incorporated additive under the conditions expected during storage and printing operation.
The heating the dye-laased cured ink nay or may nut be carried out to reduce the uncured level of uncured monomers of the curable component on the substrate. With the dye-based formulation, the heating step of the process causes the dye to set. With sublimation dyes, for example, heat causes dye particles to sublime into the substrate such as, for example, into polyester fabric fibers. The heating process causes dyeing by the dispersion process, particularly with a subclass of such dispersion dyes known as sublimation dyes, where heat causes the dye particles to change state frcnn solid to gas directly. The heat opens pores in the polyester fiber allowing the gas to enter. It also is believed to cause the particles of dye to enter a molecular form which is more highly reFlemive and capable of producing more brilliant color on the substrate. Once the material cools, the dye particles are trapped internally in the polyester fiber, possibly reverting hack to their solid state or at least being fixed in the solid substrate fibers. Some of the dispersed dye may also be entrapped in pores in the matrix of the cured UV or other curable medium.
The matrix may be a polymerizable ink formulation or the clear polymerizable ink base with the dye suspended or otherwise contained therein. For example, the UV ink can be a clear UV ink or ink base that only contains dye particles. It may also, but need not contain an ink pigment.
Effectively, using the clear base would result in all of the coloration being derived from the sublimation or other dispersion of the dye particles in the ink into the polyester fibers of the substrate, and from the potential dyeing of the clear UV polymer itself by the dye particles. This has several advantages over other ink jet dye processes.
Firstly, spot curing with UV light freezes the UV ink drop innnediately after in hits the substrate surface. Once this ink drop is heated, the dye sublimes at the exact point where it was frozen. This eliminates the "drop spread" associated with water based and other prior dye based ink jetting prcicesses. With these other processes, the dyc carrier, usually water, must he driven out from the subsUaue, or the dye must he heated to sublime, in order to limit the drop spread via wicking. This is extremely difficult to accomplish in a timely fashion relative to the point in time when the ink drop is jetted. Ultimately, controlling the drop spread results in clearer images with considerably higher levels of color saturation and "true" color gamut representation.
By using a clear UV base ink devoid of pigments, the resulting "hand" of the fabric is softer tllall ordinary UV based pigment ink systems. 'This is due to the tact that the coloration of the substrate, where a tabric: of polyester or cotton/polyester mix, is ae;complished via the sublimation of the dye particles. As a result, the fabric fibers are believed to he colored on a molecular level. With ordinary pigment systems, the pigment particle would remain in solid form, enca psulated within the UV matrix. Since these particles are very hard by nature, the result is a significantly stiffer fabric hand. The use of a UV
clear base with only dye particles eliminates this hard hand.
The color retention after repeated washing of the clear UV + dye is extremely high. This is due to the fact that dyed fibers are the excellent at retainiu~= their color fastness after repeated washings. The only effect the washings have upon the fabric is to wash away some level of the U V
acrylate. Although a small percentage of the colored acrylate is lost during the wash process, the majority of dyed polyester fibers remain unaffected.
At the same time, the hand of the material improves as the acrylate is washed away.
The use of UV haled pigment inks that are also loaded with dye particles has several benefits. This type of ink system allows us to be unconcerned as to substrate composition.
This is possible since the pigment based UV ink is subsreate indifferent. At the same time, if the substrate contains a polyester or polymer, the dye portion of this ink will dye it during the heating/sublimation or other dispersion process. If the substrate is devoid of dyeable components, then the dye particles will color the UV polymer during the heating process.
This combined dye + pigment matrix can afford the user the benefits of a substrate independent ink while offering the additional benefits of color fastness on washable materials containing polyester fibers or polymers.
At the same time, this pigment + dye UV ink system retains all of the advantages discussed above.
With the dye-based inks, the heat sets the dye, which applies to many dyes and many substrates. UV
ink can be only the ink base, without a pigment. Sublimation of dispersed dye is the mechanism applicable to polyester, but the concept is not limited to sublimation or to polyester. For polyester dyeing can occur by heating -IS-the dispersed dye without getting to sublimation, hut i n practice, the majority of the dyeing involves subl i oration.
Sublimation was at one time thought to be something to be avoided. Dispersed dye can be used on polyester mix. It is thought that a UV ink matrix with reactive dye can be used for cotton. There are other dye groups.
Most dye groups will work usin~~ a UV or other polymerizable matrix. Dyes that nmst be carried in solution are believed to work less effectively, as is the case with acid dyes, such as mordant dyes. Direct or substantive dyes are expected to work with this process more effectively. For reactive dyes and dyes that require water solution, water matrix UV can be used, and steam setting can I>e used to set such dyes.
In addition to heat, other n1eC11aIlISIIIS Cal1 be used for setting the dye, which can he determined from Chose nlEChaIIISInS COlllnlollly used with particular dyes and substrate combinations. However, the major and most important conmnercial use expected in the near future will involve heat curing of UV carried dye on polyester.
Referring further to Fig. l, the quilting station 27 is located downstream of the oven 26 in the preferred embodiment. Preferably, a single needle quilting station such as is described in U.S. Patent Application Serial No. 08/831,060 to Jeff Kaetterhenry, et al. and entitled Web-fed Chain-stitch Single-needle Mattress Cover Quitter with Needle Deflection Compensation, which is expressly incorporated by reference herein, now U.S.
Patent No. 5,832,849. Other suitable single needle type quilting I71aCI1111eS
W Ith WIlIGh the present invention may be used are disclosed in U.S. Patent Applications Serial Nos. 08/497,727 and 08/687,225, both entitled Quiltin~~
Method and Apparatus, expressly incorporated by reference herein, now U.S.
Patents Nos. 5,640,916 and 5,685,250, respectively. The duiltin~= station 27 may also include a multi-needle quilting structure such as that disclosed in U.S. Potent No. 5,154,130, also expressly incorporated by reference herein. In the figure, a single needle quilting head 38 is illustrated which is transversely moveable on a carriage 39 which is longitudinally moveable on the frame l l so that the head 38 can stitch 360" patterns on the multi-layered material 29.
The controller 35 controls the relative position of the head 38 relative to the multi-layered material 29, which is maintained at a precisely known position by the operation of the drive 22 and conveyor 20 by the controller 35 and through the storage of positioning information in the memory 36 of the controller 35. In the quilting station 27, the quilting head 38 quilts a stitched pattern in registration with the printed pattern 34 to produce a combined or composite printed and quilted pattern 40 on the multi-layered web 29. This may be achieved, as in the illustrated embodiment by holdings the assembled web 29 stationary in the duiltin~~ station 27 while the head 38 moves, on the frame 1 I, both n~ansversely under the power of a transverse linear servo drive 41, and longitudinally under the power of a longitudinal servo drive 42, to stitch the 360° pattern by driving the servos 41,42 in relation to the known position of the pattern 34 by the controller 35 based on information in its memory 36. Alternatively, the needles of a single or multi-needlequilting head may be moved relative to the web 29 by movie ~ the quiltin~~ head 38 only transversely relative to the frame 1 1 while movie the weh 29 longitudinally relative to the quilting station 27, under the power of conveyor drive 22, which can be made to reversibly operate the conveyor 20 under the control of the controller 35.
In certain applications, the order of the printing and quilting stations 25,27, respectively, can be reversed, with the printing station 25 located downstream of the quilting station 27, for example the stuion 50 as illustrated by phantom lines in the fi_ure. When at the station 50, the printing is registered with the quilting previously applied at the quilting station 27. In such an arrangement, the function of the curing station 26 would also be relocated to a point downstream of both the quilting station 27 and printing station ~0 or be included in the printing station 50, as illustrated.
'fhe cutoff station 28 is located downstream of the downsn~eam end of the conveyor 20. The cutoff station 28 is also controlled by the cimtroller 35 in synchronism with the quilting station 27 and the conveyor 20, and it may be controlled in a manner that will compensate for shrinkage of the nntlti-layered material web 29 during quilting at the quilting station 27, or in such other manner as described and illustrated in U.S. Patent No.
5,544,599 entitled Program Controlled Quitter and Panel Cutter System with Automatic Shrinkage Compensation, hereby expressly incorporated by reference herein. Information regarding the shrinkage of the fabric during quilting, which is due to the gathering of material that results when thick, tilled multi-layer material is quilted, can be taken into account by the controller 35 when quilting in registration with the printed pattern 34.
The panel cutter 28 separates individual printed :md quilted panels 45 from the web 38, each bearing a composite printed and quilted pattern 40. The cut panels 45 are removed from the output end of the machine by an outfeed conveyor 46, which also operates under the control of the controller 35.
Piezo print heads useful for this process are made by Spectra of New Hampshire. UV curing heads useful for this process are made by I union UV Systems, Inc., Gaithersburg, Maryland.
An alternative embodiment of the invention is the ink jet printing machine 600 illustrated in Fib. 2.
The machine 600 is a roll-to-roll ink jet printing machine that is particularly configured for printing onto wide textile webs. Such machines are particularly useful for printing a facing layer of material which may then be transferred to a quilting machine on a separate quilting line or to feed material downstream to a quilting station as in the embodiment illusu-ated in Fig. 1, described above. The machine 600 is also particularly suited to print on textiles that are not necessarily to be used in a quilted product, such as for signs, banners, apparel and other products.
'fhe printing machine 600 has a stationary housings 601 with a longitudinal extent represented by arrow 602 and a transverse extent represented by arrow 603. 'fhe machine 600 has a front end 604 from which is advanced a substrate web of textile material 60~ downstream in the longitudinal direction. The material nary he a grcige broods textile material or some other nruerial on which printing is desired. Where the material is a textile, it can have been preconditioned by precoating, shaving or singeing of the surface to be printed to eliminate dust and lint that could collect on the print heads and potentially contribute to clogging of the nozzles.
Failure to remove the fuzz can cause the fuzz or dust to I>e sucked into the nozzle orifices as the flow reverses between dot ejection s, which could clog the nozzles.
An operator station 606 is provided at the right side of the front end of the housing 601 having a push button control panel 607 and a touch screen and display 608. The housing 601 includes a base assembly 609 which supports the machine 600 and encloses the supply of substrate material as described in connection with Fig. 3 below. Across the top of the hOLICIII~~ 601 transversely and supported on the base 609 extends an information bridge 610. The information bridge 610 has tour display screens 6l l-614 facing the front 604 of the machine 600. From the control panel 606 an operator can select the information to be displayed on each of the screens 6l I-614. Such information can include status data, machine parameter settings, scheduling, batch and product information, pattern data, machine status and alarm conditions, or other information useful in operating the machine. One c>r more of the screens 61 I-614 can also be set to display video images of the _ l7_ printing area or the substrate downstream of the printing station from information captured by video cameras (not shown) mounted on the machine 600.
The base 609 of the housing 601 has a conveyor table 615 on the top thereof on the upwardly facing horizontal surface of which is supported a length of the substrate web 605 for printing, as illustrated in Figs. 3 and 4. The conveyor table 615 has a conveyor belt 616 that extends transversely across the width of the table 615 on transversely extending rollers 6 L7 and 61 S that are respectively rotatably mounted at the front and hack of the base 609 of the housing 601. The belt 6L6 extends across the width of the frame 601 and rests on a smooth stainless steel vacuum table 620, which has therein an arrayoFupwardlyfacing vacuum holes 621 which communicate with the underside of the belt 616. The belt 616 has a high friction rubber-like polymeric sul-face 622 to help prevent a horizontal sliding of the substrate 605 and through which au array of holes 623 is provided to facilitate COI11I111II11latIUl1 Of the vacuum from the vacuum table 620 to the substrate 605. The belt 616 is inelastic and has an open weave backing 107 which provides dimensional stability to the belt 616 while allowing the vacuum to be connnunicated between the holes 621 of the vacuum table 620 and the holes 623 in the surface 622 of the belt 616. The forward motion of the substrate 605 relative to the on the housing 601 is precisely controllable by indexing of the belt 616 by control of a DC brushless servo drive motor 624 (Fig. 3) for the rollers 617,618 with signals from a controller 625 behind the operator panel 606 on the housing 601. The indexing of the belt 616 is controllable to an accuracy of about 0.0005 inches to move the substrate web 605 relative to the housing 601.
Fixed to the base 609 of the housing 60l and extending transversely thereof is a printing bridge 630, above the conveyor table 615 and below the information bridge 6 L0. The printing bridge 630 supports a print head carriage 631 for transverse movement above and parallel to the substrate 605 supported on the conveyor table 615, as illustrated in more detail in Figs. 3 and 4. The bridge 630 has a pair of rails 632 on the front side thereof on which the carriage 631 is adapted to move. A linear servo motor 633 has a stator bur 633a containing a linear array of permanent magnets mounted across the front face of the printing bridge 630 and an armature 633b fixed to the carriage 631 and electrically connected through a wire cage chain 634 on the bridge 630 to the controller 625. An encoder 636 also extends across the front of the bridge 630 and provides feedback information to the controller 625 as to the position of the carriage 631 on the bridge 630. Linear motol:s such as the servo motor 633 are preferred because they are easier to tune, reduire little service, and have better acceleration and deceleration than belt or other drive systems. Because of their accuracy, printing can be carried out while the heads 640,641 are accelerating or decelerating, with progrannned compensation in the timing of the jetting of the ink being made by the controller 625. This improves the speed and efficiency of the print operation by allowing the print heads 640,641 to use acceleration and deceleration time and to skip at high speed across areas of the substrate 605 that will have no printing and to areas at which ink is to be deposited, thereby 17111111111ZIIlg the time during which the print head is not depositing ink on the substrate. Accordingly, linear servo motors to transversely move the carriage 63l that carries the print heads 640,641across the bridge 630 are preferred for the machine 600.
The print head carriage 63l has fixed at the bottom thereof two sets 640,641, each having tour ink jet print heads 640a-d,641a-d. The print heads of each set are arranged in a transverse row so that they print successively along a transverse strip across the substrate 605 as the print head carriage 631 moves transversely across the bridge 630 to respectively apply the Four colors of a CMYK color set. The ink jet printing heads _ 18_ G40a-d,G4la-d each include a linear array of two hundred fifty-six (25G) ink jet nozzles that extend in the longitudinal direction relative to the frame G01 and in a line perpendicular to the direction of travel of the carriage G31 on the bridge G30. The nozzles of each of the heads G40.G41 are configured and controlled to simultaneously but selectivelyjet UV ink of one of the CMYK colors, and can print a strip of 25G pixels side by side across the substrate G05 at 15,000 dots per second. The spacing of the nozzles is, in the embodiment herein described, 90jets per linear inch, so that the print heads are each slightly less than three inches wide. One pass of the print heads prints, for example, prints a transverse strip about 2.85 inches wide of ninety rows of pixels. With the two sets of heads G40 and G41, the strip is about 5.7 inches wide. By indexing the web 1/180th of an inch and printing with another pass of the carriage G31, which can be in the opposite direction, a longitudinal resolution of 180 dots per inch (dpi) can be achieved, as illustrated in Fig. S. With four passes of the print heads, indexing between the scans I/3GOth inch, a longitudinal dot resolution of 3G0 dpi can be achieved. Schemes to reduce artifacts and achieve different levels of printing quality involve activating half or one-third of the jets and scanning two or three times. indexing as required.
Transverse resolution is settable at any resolution up to approximately 720 dpi by controlling the resolution and timing of the information sent by the controller G25 to the print heads. A transverse dot resolution is preferably maintained close to the longitudinal resolution being used.
Ink is supplied to each of the print heads G40a-d,G4la-d by a respective one.
of a set of eight ink supplies (not shown) in the left side of the base G09 of the housing GO1, which are connected to the respective heads through tubes carried by the wire cage G34. Each of the ink supplies includes a collapsible plastic bag and a peristaltic pump to supply UV ink to one of the ink jet print heads G40a-d,G4la-d. Each collapsible supply bag is coupled to one of the peristaltic pumps via a tube that may include a quick disconnect. The peristaltic pump in turn supplies ink through a tube to a respective one of the ink jet print heads. An optional intervening reservoir may be provided in each tube between the pump and the print head to allow intermittent operation of the peristaltic pump or to handle intermittent demands exceeding pump output.
In the preferred and illustrated embodiment, the ink is ultraviolet light polymerizable ink composed essentially of polymerizable monomers which are stable unless and anti I
exposed to a sufficient level of UV light to initiate a polymerizing reaction. UV light is provided by a pair of UV
curing heads G45,G4G mounted on each side of the carriage G31 to expose the ink immediately after it is deposited onto the substrate G05 by the print heads G40,G41. The UV light heads G45,G4G operate alternatively, with the head on the side of the carria ~e that trails the print heads G40,G41 being ;activated to freeze the dots of ink within approximately 0.05 to 0.20 seconds after being deposited as the carriage G31 moves transversely on the bridge at approximately forty inches per second. The location of the heads G45,G4G has tile advantage of curing any atomized UV ink that might be produced by the nozzles of the print heads, thereby turning the liquid monomers into a dust thaC Is less likely to be harmful. An optional ;additional UV light curing head G47 may be provided on a separate carriage G48 (as shown in phantom in Fig. 3) to move across the back of the bridge G30 independently of the movement of the print head carriage G31 to more thoroughly cure the ink by scanning the substrate GOS downstream of the print heads G40,G41.
The supply of the substrate material GOS is loaded on a roll G50 onto a sliding carrier G51 that slides out of the base G09 of the housing G01 for loading and returns to the posICI0I1 ShOwll Ill Fig. 3 for operation of the machine G00. The web of the nuaterial GOS extends from the roll G50 around an idler roller G52, around the l9_ bottom of a vertically moveable accunwlator roller G~ 3 and over the conveyor belt GIG on the top of the conveyor table GIS. The accumulator roller G53 is weighted and supported by the web of material GOS so as to apply a uniform tension on the web of material GO~. 'fhe ends of the shaft of the roller G53 ride in vertical tracks configured to keep the roller level. Limit switches or other detectors (not shown) sense upper and lower pOSltl011s Ot the accumulator roller G53 so that the amount of material advancing from the supply roll G50 can he controlled. At the rear or downstream end of the conveyor table G I5, a pinch roller G19 is provided to clamp the web GOS against the belt 61G as it passes around the roller G18.
Below the nip of rollers G18 and G19 is provided a heater GGO. The web of material GOS enters the heater GGO, which heats the substrate GOS to reduce the content of uncured monomers of the UV ink in the same manner as the heating station 2G described above in connection with the embodiment 10 of Fig. 1. Rather than using heated air, as in the case of heating station 2G, the heater GGO
contacts the substrate GOS with one or more heated platens, which quickly bring the substrate to a temperature of 3G0°F within approximately one to two seconds. The heating station or heater GGO has a path therethrough of from about thirty inches to about forty inches for the web G05. The heater GGO includes an initial heated stainless steel bullnose platen GG 1 is positioned to contact the under surface of the material G0~ opposite the side on which the ink from the print heads G40,G41 has been deposited. The hullnose platen GGI brie ~s the substrate GOS to a desired temperature of 300-380° in one to two seconds, where hot air takes from 30 seconds to 3 minutes. The web GOS passes over a second bul1nosc platen 6G2 downstream of the first platen GG I , which contacts the ink bearing side of the substrate GOS, insuring that the temperature of the. substr;Ue GOS, and particularly the ink, is at the desired temperature throughout the thickness of the nuuerial GOS. Once brought to temperature, the substrate GOS is maintained at the desired temperature by a series of additional plates GG3,GG4. In lieu of the additional plates, other ways of maintaining the desired temperature for another thirty seconds more or less, such as with heated air or radiant heaters, would be adequate. An exhaust system (not shown) connects to the heater GGO to exhaust and dispose of any vapol:s that may contain monomers of the ink. Such exhaust may be connected to an electrostatic carbon filter and the air therefrom returned to the environment.
At the outlet of the heater GGO a series of rollers GGG take up and roll the printed material web GOS.
The series of rollers GGG includes another aeetlnltllat0l' roller GG7 which maintains tension on the web GOS
downstream of the nip of the rollers G 18,G 19.
As illustrated in Fig. ~, at the right side of the path of the print head carriage G31 is provided a head cleaning station G70. Periodically in the course of the printing of a web of material GOS, for example, after the printing of some length of web, twenty meters for example, or whenever an operator determines that the heads need to be cleaned, the carriage G31 is traversed to the right side of the brid~~e G30 over the cleanin ~ station G70.
The cleaning station G70 is provided with . pan G71 for collecting ink. When the heads are moved to the cleaning station G70, they pass over a slot G72 in a wiper blade mounting block G73 and ink is jetted from the heads into the pan G71 to clear the heads. 'fhe cleaning station G70 is also provided with an array of longitudinally extending= upwardly projecting polyurethane wiper blades G75 that are mounted to the block G73.
The carriage G31 is operated to move on the bridge G 30 to wipe the heads G40,G41 back and forth over the wiper blades G75 to wipe the bottom faces thereof which house the nozzles free of excess ink or dust. The blades are made of a polymeric material such as polyurethane and held to the block G73 in slotted blade holder members G77 fixed to the top of the block G73. Slots G7G are provided in the block G73 so that ink wiped from the heads I>y the blades 675 drains into the collectin~T pan 671. Once the heads are cleaned, the carriage resumes the scanning and printing of the web 605. Such head cleaning is progrannned to occur automatically, periodically durin~~ the printing process, when an automatic held cleaning option is selected by the operator.
Operati<m oFthe machine 600 is carried nut at the control panel 606 described above. I' ig. 6 illustrates the main control window 680 displayed on the screen 608 of the panel 606. The window 680 includes a function key 681 and set of buttons 682 for assigning functions to the hard buttons 607 on the panel 606, such as manually advancing the web 605, moving= the slide 65l to load a roll 650 and facilitating other such operator procedures, and for selecting the information to be displayed on the screens 6l 1-614 on the information bridge 610. The operator can manually choose a selected pattern, which is displayed in window 683, by pressing the button 684, to open the pattern select window 684x, which displays Icons 683a of the available patterns, as illustrated in Fig. 6A. The operator can also set up printer parameters by pressing the button 685 on window 680, which opens the printer setup window 685a illustrated in Fig. 6B. The operator can further configure the printer by pressing the button 686 on window (iSO, which opens the printer configuration window, various pages 686a,686b of which are illustrated in Figs. 6C and 6D. Input, printed output and other communication functions can be controlled by pressing the button 687 while diagnostic information can be displayed by pressing the button 688. Speed and timing information is displayed in boxes 689 while batch and job status data, such as items and duantities completed and job (product or customer) identification data is displayed in boxes 690.
The machine 600 is configured to function in accordance with the batch control and automatic scheduling processes described in U.S. Patent No. 6,105,520, by.lames T. Frazer, Von Hall, Jr. and M. Burl White entitled Quilt Making Automatic Schedulin« System and Method, hereby expressly incorporated by reference herein.
Fig. 7A shows a printing_ apparatus 700 through which a web or other substrate 71 I of woven or knitted polyester textile material is being fed Ft>r printing. The apparatus 700 includes a support table 702 over which the web 71 1 is fed. A fixed bridge 7l3 extends transversely across the path of the web 71 I over the table 702. A printhead carriage 714 is mounted to move across the bridge 713, driven by line:u servo motors 717.
On the carria~~e 714, an ink jet printhead 715 is supported and oriented so as to jet UV curable ink onto the substrate 71 l on the table 702. Also mounted on the carriage 714 on opposite sides of the printhead 715 is a pair of UV light curing heads 716 oriented to expose UV ink jetted onto the substrate 711 innnediately after the ink reaches the substrate.
The table 702 is made of metal, for example stainless steel, and has an upwardly facing surface that is coated, at least in the area on which the printhead 715 prints, with a layer of release material 704 such as 'fLl~LON, a silicone release material or some other material to which the ink will either not stick, or will stick with such low adhesive force that it can be easily wiped or otherwise removed from the release material layer 704. Ideally, the release material layer 704 has enough adhesion to the ink to prevent it from wiping off by the passage of the substrate 711 over the table 702, hut has sufficiently low adhesion to allow the ink to later be wiped or otherwise removed fmm the layer 704 with relative ease.
Alternatively, the ink on the layer 704 may normally stick to the layer 704 but he renu>vahle with a solvent or other cleaning a gent.
The UV curin~~ heads l6 preferably have li~~ht sources that Focus over a sufficiently lone depth of field so as to expose and cure not only ink that deposits on the substrate 71 1 but that which passes through pores or holes in the weave of the substrate 71 1 and collects on the underlying release material layer 704. As a result, the ink on the release material 704 is sufficiently set or cured so as to be in a powder or otherwise substantially _21_ solid state as it enters the cleaning station, so that it can be wiped or otherwise easily removed from the surface of the release material 704.
The table 702 may be a vacuum table, with vacuum holes 721 throu:,~h the layer 704 to allow the vacuum to pass through to help hold the substrate 7l l in place for printing.
Fig. 7B shows a printing apparatus 7l0 tlwough which web 71 I of woven or knitted polyester textile material is being fed for printing. The apparatus 710 includes a support table 7l2 over which the web 71 I is fed. Fixed bridge 13 extends transversely across the path of the web 7 l l over the table 712. Printhead carriage 7l4 is mounted to move across the bridge 713, driven by linear servo motors 7 l7. On the carriage 714, ink jet printhead 715 is supported and oriented so as to jet UV curable ink auto the substrate 711 on the table 712. f\Iso mounted on the carriage 7l4 on opposite sides of the printhea d 715 are UV
light curing heads 716 oriented to expose UV ink jetted onto the substrate 71 I innnediately after the ink reaches the substrate.
Positioned over the table 712 between the table 712 and the substrate 711 is a sheet of release material 720, such as TEFLON or a silicone coated film material or some other material to which the ink will not easily stick or will stick with such low adhesive force that it can be easily wiped or otherwise removed from the surface of the release material 720. The release material 720, in the apparatus 710, is in the form of a web or endless belt. The belt of release material 720 moves with the substrate 711 through the apparatus 710 and returns tlwough a path 722 under the table 712. Along the path 722 is a cleaning station 723 through which the belt of release material 720 passes. The cleaning station 723 contains brush and vacuum elements (not shown) which wipe ink from the surface of the belt 721 :utd remove it to n filter (not shown).
The UV curing heads 716 preferably hove light sources that focus over a sufficiently long depth of field so as to expose and cure not only ink that deposits on the substrate 71 l hut that which passes tlwou~~h pores or holes in the weave of the substrate 711 and collects on the underlying belt of release material 720. As a result, the ink on the release material 720 is sufficiently set or cured so as to be in a powder or otherwise substantially solid state as it enters the cleaning station, so that it can be wiped or otherwise easily removed from the surface of the release material 720.
Where the substrate is sufficiently porous for the ink to pass through it, but not sufficiently porous to allow enou~~h UV light to pass so as to cure the ink on the protective material, the moveable belt may be used to collect the ink while moving with the substrate so the ink does not smear, then when the belt separates from the substrate, a separate source of UV light can be used to solidity the ink on the protective layer. Alternatively, the ink may be removed in liquid state from the belt.
The table 712 may be a vacuum table, in which case the material 720 should be sufficiently porous to allow the vacuum to pass through to help hold the substrate 711 in place for printing.
Fig. 7C shows a cross-sectional view of a printing apparatus 705, similar to the apparatus 700 of Fig. 1, and through which the web or other substrate 711 of woven or knitted polyester textile material is being fed for printing. The apparatus 705 includes a platen or table 706 over which the web 711 is fed. Printhead carriage 7l4 is mounted to move across the bridge as illustrated in Fig. 7A
and has ink jet printhead 715 supported thereon and oriented so as to jet UV eurable ink onto the substrate 711 above the table 705. Also mounted on the carriage 7l4 on opposite sides of the printhead 715 is the pair of UV light curin~~ heads 716 oriented to expose UV ink jetted onto the substrate 7l l innnediately after the ink reaches the substrate.

The table 705 may be made of metal, for example stainless steel, and has an upwardly facing surface that is coated, at least in the area on which the printhead 7l5 prints, with the layer of release material 702 thereon. Instead of providin~~ the release material layer 704 with enough adhesion to the ink to prevent it from wiping off by the passage of the substrate 71 l over the table 706, the substrate 71 l is maintained out of contact with the layer 704 and table 705 in the region between the printhead 715 and the table 706.
Spacing between the table 706 and the substrate 711 is maintained by guide structure such as side securements, support wires or mesh, sets of transverse rollers, or other structure that so maintains the substrate 11 for printing. The ;guide structure may include sets of transversely extending elements to pinch the fabric and stretch it parallel to and spaced from the table 706. The pinch element sets may each include a pair of smooth low friction bars, a bar and roller set, or a pair of rollers. The pinch elements may, for example, hold the substrate in sufficient tension to keep it in position relative to the printhead for printing and to keep it out of contact with the table 706. (n the embodiment of Fig. 7C, the guide structure maintains the substrate 711 in tension and spaced alcove the table 706 a short distance, for example 1/4 inch, so that the material does not touch the surface of the table 706. The tension in the substrate 711 may, for example as shown in Fig. 7C, be maintained by two spaced sets 731 and 7 32 of rolls 73 I a,73 l h and 732a,7326, one set 731 upstream of the printhead 7 l5 and one set 732 downstream of the printhead 715, such that the sets are horizontally spaced about three or tour inches apart.
The UV curing heads l6 preferably have li~~ht sources that focus over a sufficiently long depth of field so as to expose and cure not only ink that deposits on the substrate 711 but that which passes through pores or holes in the weave of the substrate7l I and collects on the underlying release material layer 704 on the table 706 spaced below the substrate 711. As a result, the ink on the release material 704 is sufficiently set or cured so as to be in a powder or otherwise substantially solid state as it enters the cleaning station, so that it can be wiped or otherwise easily removed from the surface of the release material 704.
With the embodiment 705 of Fig. 7C, the platen 706 is periodically wiped of the ink that passes through the porous substrate 7 I I onto the release layer 704.
The above description is representative of certain embodiments of the invention. Those skilled in the art will appreciate that various changes ~md additions which may be made to the embodiments described above without departing frenn the principles of the present invention.

Claims (62)

Therefore, the following is claimed:

1. A method of printing an image onto a substrate comprising:
depositing onto a substrate a polymerizable substance that is stable until contacted with a curing medium, the substance having a dye contained therein;
at least partially curing the substance on the substrate by applying the curing medium thereto, the curing including polymerizing the substance by initiating a polymerizing reaction in the substance and maintaining the reaction until the substance is substantially polymerized; and forming the image on the substrate by dying the substrate with the dye from the deposited substance.

2. The method of printing of claim 1 wherein:
the substrate is a textile;
the substance includes UV curable monomers that polymerize when contacted by UV radiation;
the depositing includes jetting the substance containing the dye onto the textile;
the curing includes contacting the monomers deposited on the substrate with UV
radiation to form a polymer on the surface of the textile; and the forming of the image occurs as dye from the surface of the substrate moves into bonding contact with fibers of the textile.

3. The method of claim 1 or claim 2 wherein:
the depositing includes jetting an ink composition containing a UV curable component and a dye component; and the curing includes substantially curing at least the jetted UV curable component on the substrate by exposing the UV curable component to UV light, the curing resulting in a substantially cured UV component on the substrate containing the dye component.

4. The method of claim 3 wherein:
the forming of the image includes heating the substrate having the substantially cured UV cured component thereon and thereby effecting the dycing of the fabric with the dye component.

5. The method of claim 4 wherein:
the curing results in the substantially cured UV component containing uncured monomers of the UV
curable component; and the heating includes reducing the level of the uncured monomers of the UV
curable component on the fabric.

6. The method of claim 1 or claim 1 wherein:
the substance has a pigment included therein: and the curing includes fixing the pigment in the cured substance on the surface of the substrate.

7. The method of claim 1 or claim 2 wherein:
the depositing includes jetting onto the substrate a substance containing a UV
curable component and a dye component; and the curing includes substantially curing at least the UV curable jetted component on the substrate by exposing the UV curable component on the substrate to UV radiation.

8. The method of claim 7 wherein:
the forming of the image includes heating the substance containing the substantially cured exposed UV
component and the dye component on the substrate.

9. The method of claim 8 wherein:
the substantially cured UV curable component includes at least some uncured monomers and the heating of the substance includes reducing the amount of uncured monomers on the substrate.

10. The method of claim 7 further comprising:
heating the substance containing the substantially cured exposed UV component and the dye component on the substrate;
the heating includes contacting the substrate with a heated plate.

11. The method of claim 1 or claim 2 wherein:
the depositing includes printing the substance onto a large area substrate.

12. The method of claim 1 or claim 2 wherein:
the at least partial curing of the substance on the substrate includes freezing the substance on the substrate by applying the curing medium to the substance immediately upon the printing thereof to reduce the spread of the substance on the substrate.

13. The method of claim 1 or claim 2 wherein:
the at least partial curing of the substance on the substrate includes freezing the substance on the substrate by exposing the substance to UV light immediately upon the printing thereof onto the substrate to reduce the spread of the substance on the substrate.

14. The method of claim 1 wherein:
the forming of the image includes contacting the substrate having the at least partially cured substance thereon with a heated plate.

15. The method of claim 1 wherein:
the forming of the image includes heating the substantially polymerized substance and the dye contained therein while on the substrate to effect the dyeing of the substrate.

16. The method of claim 1 or claim 14 or claim 15 wherein:
the depositing includes the jetting of the substance onto the substrate.

17. The method of claim 15 wherein:
the at least partially cured substance includes at least some unpolymerized monomers and the heating includes reducing the amount of unpolymerized monomers on the substrate.

18. The method of claim 1 or claim 2 wherein:
the substance is a curable liquid having the dye component contained therein;
the curing includes at least partially solidifying the liquid on the surface of the substrate.

19. The method of claim 18 wherein:
the forming of the image includes heating the at least partially solidified liquid on the surface of the substrate so as to effect the dyeing of the substrate.

20. The method of claim 1 wherein:
the depositing includes jetting onto the substrate a curable liquid polymer having the dye suspended therein;
the curing includes substantially curing the liquid polymer on the substrate to fix the position of the suspended dye on the substrate.

21. The method of claim 20 further comprising:
heating the substantially cured liquid polymer on the substrate to activate the dye and thereby effect the dyeing of the substrate.

22. The method of claim 21 wherein:
the dye is a sublimation dye;
the heating includes heating the dye to sublime the dye to dye the substrate.

23. The method of claim 21 wherein:
the curable liquid polymer is a UV curable substance;
the dye is a sublimation dye;
the curing includes exposing the substance to UV light for a sufficiently short time after jetting the substance onto the substrate to at least partially prevent a spreading of the polymer on the substrate; and the heating includes heating the dye to sublime the dye.

24. A digital printing method comprising:
driving a printhead across a substrate with a linear servo motor; and digitally printing an image on the substrate therewith.

25. The method of claim 24 wherein:
the printing includes jetting ink from the print head onto the substrate.

26. The method of claim 25 further comprising:
controlling the jetting of the ink by advancing the timing thereof in relation to the speed of the print head across the substrate:

27. The method of claim 25 further comprising:
controlling the jetting of the ink by advancing the timing thereof in relation to the speed of the print head across the substrate to compensate for transverse displacement of the ink due to the velocity of the print heads parallel to the substrate.

28. The method of claim 24 wherein:
the driving of the print head includes accelerating and decelerating the print head while driving it across a substrate with the linear servo motor; and the printing includes printing on the substrate while the head is accelerating or decelerating.

29. The method of claim 28 wherein:
the printing includes jetting ink from the print head onto the substrate while the head is accelerating or decelerating.

30. The method of claim 29 further comprising:
controlling the jetting of the ink by advancing the timing thereof in relation to the speed of the print head across the substrate.

31. The method of claim 25 further comprising:
controlling the jetting of the ink by advancing the timing thereof in relation to the speed of the print head across the substrate to compensate for transverse displacement of jetting ink due to the velocity of the print heads parallel to the substrate.

32. The method of claim 24 wherein:
the substrate is a textile; and the printing includes jetting ink from the print head onto the surface of the textile.

33. A method of printing onto textiles comprising:
removing fibers from the surface of the substrate; then ink jet printing onto the substrate.

34. The method of claim 33 wherein:
the removing of the fibers includes shaving the surface of the substrate.

35. The method of claim 33 wherein;
the removing of the fibers includes singcing the surface of the substrate.

36. The method of claim 33 wherein:
the removing of the fibers is performed on the substrate when supported on the frame of a printing machine; and the printing is carried out while the substrate is still supported on the frame of the printing machine.

37. An ink jet printing apparatus comprising:
means forgetting onto a substrate a polymerizable substance containing a curable component and a dye component;
means for substantially curing at least the curable jetted component on the substrate by exposing the curable component on the substrate to a curing medium and therewith polymerizing the substance by initiating a polymerizing reaction in the substance and maintaining the reaction until the substance is substantially polymerized.

38. The apparatus of claim 37 further composing:
means for heating the substrate having the cured component and dye component thereon.

39. The apparatus of claim 37 further comprising:
a heated plate configured to thermally contact the substrate having the cured component and dye component thereon.

40. The apparatus of claim 37 further comprising:
a bridge extending parallel to the substrate;
an ink jet printhead carriage moveable on the bridge;
a linear servo connected to the badge and the printhead carriage so as to drive the carriage across the bridge; and a programmed controller connected to the servo to control the motion of the carriage on the bridge.

41. A digital printing apparatus comprising:
a substrate support;
a linear servo motor extending parallel to the support:
a digital printhead moveable on the linear servo motor parallel to the support and directed toward the support;
a controller operable to drive the linear servo motor parallel to the support and to operate the print head in synchronism with the movement of the servo motor so print an image on a substrate on the support in accordance with data from an electronic source file.

42. The apparatus of claim 41 wherein:
the printhead is an ink jet printhead.

43. The apparatus of claim 42 wherein:
the controller is operable to time the jetting of the ink from the printhead in relation to the speed of the linear servo motor.

44. The apparatus of claim 42 wherein:
the controller is operable to time the jetting of the ink from the printhead in relation to the speed of the linear servo motor by advancing or retarding the turning of the jetting of the ink from the printhead in relation to the speed of the print head across the substrate to compensate for transverse displacement of the ink due to the velocity of the printhead parallel to a substrate on the support.

45. The apparatus of claim 41 wherein:
the controller is operable to control the printing of the printhead so as to accurately produce an image from the electronic source file when the servo motor is accelerating or decelerating.

46. A textile printing apparatus comprising:
a substrate support;
a bridge extending across the support:
an ink jet print head moveable across the bridge and positioned to deposit a dot pattern of ink onto a substrate on the support;
a computer controlled linear servo motor positioned to move the printhead across the bridge.

47. A method of printing onto textiles comprising:
providing a substrate support with a layer of non-stick protective material;
supporting a textile having pores therein above the substrate support with the layer of non-stick protective sheet material between the substrate support and the substrate;
jetting UV curable ink onto the substrate with some of the ink passing through the pores of the substrate onto the layer of material;
exposing the jetted UV curable ink to UV light;
removing the substrate from above the support;
wiping exposed UV curable ink from the layer of protective sheet material.

48. The method of claim 47 wherein:
the non-stick protective material is a coating of material on the support to which UV ink, jetted thereon and at least partially cured, has an adhesive force sufficiently high to prevent such ink from being wiped from the coating by the friction of the substrate sliding over the support, but has an adhesive force that is, or can be made sufficiently low to allow such ink to be cleaned from the support: and the textile is supported on the substrate support in contact with the layer of non-stick protective sheet material.

49. The method of claim 47 wherein:
the supporting of the textile above the substrate support includes extending the substrate in tension, spaced from the substrate support adjacent the layer of non-stick protective sheet material at least in a region between the printhead and the substrate support

50. An ink jetting printing apparatus comprising:
a substrate table;
a layer of non-stick protective material overlying the table so as to collect, and protect the substrate support from, ink jetted toward a porous substrate over the table and passing through the porous substrate;
an ink jet printhead directed toward the ruble;
a curable head positioned adjacent the table to facilitate the curing of ink jetted from the printhead toward a substrate over the table.

51. The apparatus of claim 50 wherein the non-stick protective material is TEFLON.

52. The apparatus of claim 50 wherein the curing head includes a primary UV
light curing source positioned to expose ink that has been jetted onto a substrate over the table.

53. The apparatus of claim 52 wherein the curing source is mounted on or near a carriage on which the printhead is mounted so as to cure ink immediately after it reaches the substrate so that the dots of ink are frozen before they have a chance to flow into the substrate or spread.

54. The apparatus of claim 52 wherein the UV source has a focal length sufficiently long so that the light penetrates holes in the substrate and cures ink on the underlying layer.

55. The apparatus of claim 50 wherein the non-stick protective material is a coating of material on the table to which UV ink, jetted thereon and at least partially cured, has an adhesive force sufficiently high to prevent such ink from being wiped from the coating by the friction of the substrate sliding over the table, but has an adhesive force that is, or can be made, sufficiently love to allow such ink to be cleaned from the table.

56. The apparatus of claim 50 further comprising:
guide structure configured and positioned to support the substrate proximate to but out of contact with the non-stick protective material at least in a region between the printhead and the substrate table.

57. The apparatus of claim 56 wherein:
the guide structure includes transversely extending sets of pinch elements, one set located upstream of the printhead and one set located downstream of the printhead, to hold the substrate in tension proximate but out of contact with the table.

58. The apparatus of claim 56 wherein:
the guide structure includes transversely extending pairs of rollers, one pair located upstream of the printhead and one pair located downstream of the printhead, to hold the substrate proximate but out of contact with the table.

59. An ink jetting printing apparatus comprising:
a substrate support;
a layer of non-stick protective material overlying the support so as to collect, and protect the substrate support from, ink jetted toward a porous substrate on the support and passing through the porous substrate;
an ink jet printhead directed toward the support:
a curable head positioned adjacent the support to facilitate the curing of inkjetted from the printhead toward a substrate on the support.

60. An ink jet printing apparatus comprising:
an ink jet printhead configured to jet UV curable ink onto a substrate:
a UV curing head configured to at least partially cure UV curable ink jetted onto the substrate; and a heated plate configured to thermally contact the substrate having the at least partially cured UV
curable ink thereon.

61. The apparatus of any of claims 37 through 60 further comprising:
means for cleaning an ink jet printhead.

62. An ink jet printing apparatus comprising:
a frame having a substrate support area thereon;
an ink jet printhead configured to jet onto a substrate on the substrate support area a UV curable ink;
a UV source configured to substantially cure the UV curable ink on the substrate; and a head cleaning station beside the substrate support area having located thereat means for purging the printhead and wiping the printhead.