1. Field of Use
The present teachings relate to electrostatography and electrophotography and, more particularly, to intermediate transfer members including surface treated carbon black.
2. Background
In an electrophotographic imaging process, an electric field can be created by applying a bias voltage to the electrophotographic imaging components, consisting of resistive coating or layers. Further, the coatings and material layers are subjected to a bias voltage such that an electric field can be created in the coatings and material layers when the bias voltage is ON and be sufficiently electrically relaxable when the bias voltage is OFF so that electrostatic charges are not accumulated after an electrophotographic imaging process. The fields created are used to manipulate unfused toner image along the paper path, for example from photoreceptor to an intermediate transfer belt and from the intermediate transfer belt to paper, before fusing to form the fixed images. These electrically resistive coatings and material layers are typically required to exhibit resistivity in a range of about 107 to about 1012 ohm/square and should possess mechanical and/or surface properties suitable for a particular application or use on a particular component. It has been difficult to consistently achieve this desired range of resistivity with known coating materials.
Carbon black is the most commonly used conductive agent for use in plastics, coatings, toners and printing inks. When used in electrically resistive coatings, the desired resistivity is typically achieved by varying the carbon black loading, as well as adding dopants and additives to the final composition of the material. However, its use in electrically resistive coatings is severely limited due to its steep percolation threshold. It is typically difficult to achieve resistivities in the range of 108-1012 Ω/square.
Accordingly, there is a need to overcome these and other problems of prior art to provide new methods of processing carbon black materials which can tailor the conductivity in the range difficult to achieve by pure, untreated carbon black.
In accordance with various embodiments, there is a coating composite for imaging components. The coating composite can include a film forming resin and a plurality of surface treated carbon black particles substantially uniformly dispersed in the film forming resin, wherein each of the plurality of surface treated carbon black particles includes one or more fluorosilanes bonded to a surface of the carbon black particle.
According to another embodiment, there is an imaging component. The imaging component can include a substrate and a coating composite disposed over the substrate, the coating composite including a plurality of surface treated carbon black particles substantially uniformly dispersed in a film forming resin, wherein each of the plurality of surface treated carbon black particles comprises one or more fluorosilanes bonded to a surface of the carbon black particle, and wherein the coating composite has a surface resistivity in the range of about 106 Ω/square to about 1013 Ω/square.
According to yet another embodiment, there is an apparatus for forming an image. The apparatus can include a charging station for uniformly charging a surface of an image receiving member and an imaging station for forming a latent image on the surface of the image receiving member. The apparatus can also include a developing station for converting the latent image to a visible image on the surface of the image receiving member, an intermediate transfer member positioned between the image receiving member and a transfer roller for transferring the developed image from the image receiving member to a media, wherein at least one of the intermediate member and the transfer member can include a coating composite, the coating composite including a plurality of surface treated carbon black particles substantially uniformly dispersed in a film forming resin, wherein each of the plurality of surface treated carbon black particles includes one or more fluorosilanes bonded to a surface of the carbon black particle, and wherein the coating composite has a surface resistivity in the range of about 106 Ω/square to about 1013 Ω/square.
Additional advantages of the embodiments will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present teachings. The advantages will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present teachings, as claimed.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present teachings and together with the description, serve to explain the principles of the present teachings.
Reference will now be made in detail to the present embodiments, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present teachings are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all sub-ranges subsumed therein. For example, a range of “less than 10” can include any and all sub-ranges between (and including) the minimum value of zero and the maximum value of 10, that is, any and all sub-ranges having a minimum value of equal to or greater than zero and a maximum value of equal to or less than 10, e.g., 1 to 5. In certain cases, the numerical values as stated for the parameter can take on negative values. In this case, the example value of range stated as “less that 10” can assume negative values, e.g. −1, −2, −3, −10, −20, −30, etc.
The coating composite 101 for imaging components shown in
The coating composite 101 for imaging components shown in
Generally, in an electrostatographic reproducing apparatus, a light image of an original to be copied can be recorded in the form of an electrostatic latent image upon a photosensitive member (e.g., the image receiving member 226) and the latent image can be subsequently rendered visible by the application of electroscopic thermoplastic resin particles which are commonly referred to as toner.
Referring to
Subsequent to the image development, the charged toner particles 23 from the developing station 228 can be attracted and held by the image receiving member 226 (e.g., photoreceptor drum), because the photoreceptor drum possesses a charge 22 opposite to that of the toner particles 23. It is noted in
In this manner, in a multi-image system for example, each of the images can be formed on the exemplary photoreceptor drum (see 226) by the image input apparatus 224, developed sequentially by the developing station 228, and transferred to the intermediate transfer member 210, when each image involves a liquid image. In an alternative method, each image can be formed on the photoreceptor drum, developed, and transferred in registration to the intermediate transfer member 210, when each image involves a dry image.
In an exemplary embodiment, the multi-image system can be a color copying system. In this color copying system, each color of an image being copied can be formed on the photoreceptor drum (see 226). Each color image can be developed and transferred to the intermediate transfer member 210. In an alternative method, each color of an image can be formed on the photoreceptor drum (see 226), developed, and transferred in registration to the intermediate transfer member 210.
The transfer roller 230 can be positioned opposite to the photoreceptor drum 226 having the intermediate transfer member 210 there between. The transfer roller 230 can be a biased transfer roller having a higher voltage than the surface of the photoreceptor drum. The biased transfer roller 230 can charge the backside 218 of the intermediate transfer member 210 with, for example, a positive charge. Alternatively, a corona or any other charging mechanism can be used to charge the backside 218 of the intermediate transfer member 210. Meanwhile, the negatively charged toner particles 23 can be attracted to the front side 215 of the intermediate transfer member 210 by the exemplary positive charge 21 on the backside 218 of the intermediate transfer member 210.
After the toner latent image has been transferred from the image receiving member 226, exemplary photoreceptor drum to the intermediate transfer member 210, the intermediate transfer member 210 can be contacted under heat and pressure to an image receiving substrate, i.e. a media (not shown). The toner image on the intermediate transfer member 210 can then be transferred and fixed (as permanent image) to the media (not shown) such as a copy sheet.
The intermediate transfer member 210 and the bias transfer roll 230 can include the coating composite 101 shown in
Any other imaging component, such as, for example, a magnetic roller sleeve and a transfer belt can include the coating composite 101, 301, 401, in a configuration as shown in
In various embodiments, the surface treated carbon black particles 104, 304, 404 shown in
Examples are set forth herein below and are illustrative of different amounts and types of reactants and reaction conditions that can be utilized in practicing the disclosure. It will be apparent, however, that the disclosure can be practiced with other amounts and types of reactants and reaction conditions than those used in the examples, and the resulting devices various different properties and uses in accordance with the disclosure above and as pointed out hereinafter.
About 10.01 g of Vulcan XC-72 carbon black (Cabot Corporation, Boston, Mass.) was added to about 108.47 g of dodecane and 1.079 g of (heptadecafluoro-1,1,2,2-tetrahydrodecyl)triethoxysilane (FOETES; Gelest, Inc., Morrisville, Pa.) in a 500 ml round bottom flask and sonicated for about 5 minutes, and then heated to reflux. The sample was allowed to stir for about 18 hours, at which point the sample was cooled to room temperature and filtered. The carbon black was washed with hexane, allowed to dry in vacuum, and analyzed by X-ray Photoelectron Spectroscopy (XPS). The XPS results shown in Table 1 confirm the attachment of FOETES onto the surface of the carbon black particles.
Dispersions were prepared by adding the FOETES-treated carbon black in various concentrations to about 1:1 mixture (by total solid weight) of Cymel 323 (a melamine from Cytec Industries Inc., Woodland Park, N.J.) and Paraloid AT-410 (Rohm & Haas Co., Philadelphia, Pa.) in methyl ethyl ketone (60% total solids). As a control, similar samples were prepared with untreated carbon black. The samples were added to about 80 g of ⅛″ stainless steel shot and roll milled over the course of about 64 hours. The shot was removed by passing the dispersions through a fine cotton filter (about 280 μm).
Each of the dispersion of Example 2 was subsequently coated on a PET substrate using about 2 mil bird bar. The films were dried in a convection oven for about 10 minutes at about 140° C. giving about 20 μm thick films. Surface resistivity was measured using a Hiresta UP Resistivity Meter with a supply voltage of about 10V.
While the present teachings have been illustrated with respect to one or more implementations, alterations and/or modifications can be made to the illustrated examples without departing from the spirit and scope of the appended claims. In addition, while a particular feature of the present teachings may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular function. Furthermore, to the extent that the terms “including”, “includes”, “having”, “has”, “with”, or variants thereof are used in either the detailed description and the claims, such terms are intended to be inclusive in a manner similar to the term “comprising.” As used herein, the phrase “one or more of”, for example, A, B, and C means any of the following: either A, B, or C alone; or combinations of two, such as A and B, B and C, and A and C; or combinations of three A, B and C.
Other embodiments of the present teachings will be apparent to those skilled in the art from consideration of the specification and practice of the present teachings disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the present teachings being indicated by the following claims.