Patent Application
20110111185
The devices and methods disclosed below generally relate to transferring an image onto a medium and particularly to transferring an image to a garment.
Different methods have been developed to transfer images onto a medium such as an article of clothing. In U.S. Pat. No. 4,066,802 to Clemens a xerographic image transfer process is disclosed. FIG. 3 of the '802 patent, reproduced here and titled as
The process of the '802 patent requires the presence of a polymeric interposed sheet to facilitate a permanent adherence of the toner material to the medium. Inclusion of the interposed sheet adds cost to the process of transferring an image to a T-shirt. In addition, the presence of an interposed sheet in areas where there is no toner can produce an esthetically unpleasing effect as well as a degree of un-comfortableness for the wearer of the garment, especially when the material of the garment is thin. Furthermore, the permanence of adherence of the toner material to the medium is dependent on the interposed sheet. The adherence may degrade over time result in the peeling of the toner material.
An apparatus for transferring indicia onto a medium is disclosed. The apparatus includes a substrate, and a mirror image of an image pattern printed onto the substrate with a phase-change ink having a phase-change temperature on a first side of the substrate, the printed mirror image configured to change phase and transfer to a medium in response to the first side of the substrate being placed in contact with a first side of the medium and sufficient heat applied to a second side of the substrate to raise the temperature of the phase-change ink of the mirror image to the phase-change temperature.
A method for making a transferable image is also disclosed. The method includes printing a mirror image of an image pattern with a phase-change ink having a phase-change temperature onto a first side of a substrate, and applying a removable protective layer over the first side of the substrate.
The foregoing aspects and other features of the present disclosure are explained in the following description, taken in connection with the accompanying drawings.
The term “printer” as used herein refers, for example, to reproduction devices in general, such as printers, facsimile machines, copiers, and related multi-function products. While the specification focuses on a web transport system that controls the transport of a web under a series of print heads, the transport system may be used with any web transport system that transports a web from one location to another. Furthermore, the device and method described herein may be used with printers that form printed images with either aqueous ink, phase change ink, or gel ink, as described below.
The term “medium” as used herein refers, for example, to an article of clothing such as a T-shirt as well as to other image receiving surfaces such as a painter's canvas.
The term “phase change ink” encompasses inks that remain in a solid phase at an ambient temperature and that melt into a liquid phase when heated above a threshold temperature, referred to as a phase-change temperature.
The terms “gel ink” or “gel-based ink” encompass inks that remain in a gelatinous state at the ambient temperature and that may be altered to have a different viscosity suitable for ejection by a print head. In particular, gel ink in the gelatinous state may have a viscosity between 105 and 107 centipoise (“cP”); however, the viscosity of gel ink may be reduced, to a liquid-like viscosity, by heating the ink above a threshold temperature, referred to as a gelation temperature. An exemplary range of gelation temperatures is approximately thirty to fifty degrees Celsius; however, the gelation temperature of some types of gel ink may be above or below the exemplary temperature range.
Some inks, including gel inks, may be cured during the printing process. Radiation curable ink becomes cured after being exposed to a source of radiation. Suitable radiation may encompass the full frequency (or wavelength) spectrum, including but not limited to, microwaves, infrared, visible, ultraviolet, and x-rays. In particular, ultraviolet-curable gel ink, referred to herein as UV gel ink, becomes cured after being exposed to ultraviolet radiation.
The term “substrate” as used herein refers, for example, to a sheet on first side of which a mirror image of an image pattern is printed. The sheet is a temporary carrier of the phase-change ink and is used for transferring the image pattern to the medium.
Referring to
In order to transfer the image pattern 106 to the medium 102, a mirror image pattern 152 of the image pattern 106 is first printed onto a first side 150 of the substrate 104, with a phase change ink as depicted in
Referring to
In one embodiment the substrate 104 can be cooled to below the ambient temperature prior to the print head 204 ejecting the phase-change ink onto the first side of 150 of the substrate 104. Pre-cooling the substrate 104 assists in quickly reconstituting the molten ink into a solid ink. A sharper image can result especially at the edges of the mirror image pattern 152. In one embodiment a gel ink can be used in place of a phase-change ink. The gel ink can be cured by using radiation curing by for example an ultraviolet light. In one embodiment a protective layer 212 can be placed over the reconstituted ink 206 to protect the ink during handling. The protective layer 212 can be any material that does not disturb the reconstituted ink 206 when the protective layer 212 is peeled off prior to placement of the substrate 104 on the first side 110 of the medium 102. In one embodiment, multiple colored phase-change inks can be used in connection with several print heads, i.e., one print head per color. Where multiple colored phase-change ink are used to generate a colored image, the computing device 202 processes the captured image from the scanner 208 to generate multiple mirror images as well as firing signals for multiple print heads. Each mirror image corresponds to a different color of the phase-change ink which is associated with a different print head for that color. Not shown in
Referring to
In addition to heat designated by reference numeral 256, pressure can also be applied to increase the pace of phase change. Also, pressure can be used to enhance the adherence of the phase change ink to the first side 110 of the medium 102 as it reconstituting from a liquid phase to a solid phase. In one embodiment, pressure in the range of about 0.01 bars to about 0.02 bars is applied to the second side 108 of the substrate 104.
Referring to
Referring to
In embodiments where multiple colored phase-change inks are used, each colored phase change ink changes phase and reconstitutes according to a corresponding phase-change temperature. Volume of the phase-change ink per unit area ejected from the print head 204 is an important aspect. Too much ink may cause a bleeding effect between boundaries defining features in the image, resulting in a less sharp image. This bleeding effect can be particularly problematic in colored images, where too much ink can result in one color of phase-change ink to bleed into another color of phase-change ink when reconstituting on the first side 110 of the medium 102. While in the case of a single colored image, too much ink may result in a lessening of the sharpness of the image, in a colored image, too much phase-change ink can result in an undesirable color bleeding between regions of differing colors. Too little phase-change ink can result in a faded image, or potentially in a blotchy image.
It will be appreciated that various of the above-disclosed and other features, and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. A few of the alternative implementations may comprise various combinations of the methods and techniques described. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art, which are also intended to be encompassed by the following claims.
