Patent ID: 12204279

Similar reference characters denote corresponding features consistently throughout the attached drawings.

DETAILED DESCRIPTION

Definitions

It should be understood that the drawings described above or below are for illustration purposes only. The drawings are not necessarily to scale, with emphasis generally being placed upon illustrating the principles of the present teachings. The drawings are not intended to limit the scope of the present teachings in any way.

Throughout the application, where compositions are described as having, including, or comprising specific components, or where processes are described as having, including, or comprising specific process steps, it is contemplated that compositions of the present teachings can also consist essentially of, or consist of, the recited components, and that the processes of the present teachings can also consist essentially of, or consist of, the recited process steps.

It is noted that, as used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.

In the application, where an element or component is said to be included in and/or selected from a list of recited elements or components, it should be understood that the element or component can be any one of the recited elements or components, or the element or component can be selected from a group consisting of two or more of the recited elements or components. Further, it should be understood that elements and/or features of a composition or a method described herein can be combined in a variety of ways without departing from the spirit and scope of the present teachings, whether explicit or implicit herein.

The use of the terms “include,” “includes”, “including,” “have,” “has,” or “having” should be generally understood as open-ended and non-limiting unless specifically stated otherwise.

The use of the singular herein includes the plural (and vice versa) unless specifically stated otherwise. In addition, where the use of the term “about” is before a quantitative value, the present teachings also include the specific quantitative value itself, unless specifically stated otherwise. As used herein, the term “about” refers to a ±10% variation from the nominal value unless otherwise indicated or inferred.

The term “optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances in which it does not.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the presently described subject matter pertains.

Where a range of values is provided, for example, concentration ranges, percentage ranges, or ratio ranges, it is understood that each intervening value, to the tenth of the unit of the lower limit, unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the described subject matter. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges, and such embodiments are also encompassed within the described subject matter, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the described subject matter.

Throughout the application, descriptions of various embodiments use “comprising” language. However, it will be understood by one of skill in the art, that in some specific instances, an embodiment can alternatively be described using the language “consisting essentially of” or “consisting of”.

For purposes of better understanding the present teachings and in no way limiting the scope of the teachings, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

A toner and method of producing toner are disclosed herein. The toner is produced by preparing a latex such as poly(styrene-methyl methacrylate-acrylic acid) [P(St-MMA-AA)] followed by preparing a pigment including fly ash. The preparation of the polymer latex uses a traditional approach to form (P(St-MMA-AA)). The reaction firstly includes a combination of ammonium bicarbonate (NH4HCO3) and sodium dodecylbenzene sulfonate (SDBS) in water. Next, using a drop funnel, styrene (St), acrylic acid (AA) and methyl methacrylate (MMA) are added to the solution while also heating to a temperature of about 70° C. and stirring for about 0.5 hours. Next, an aqueous solution of ammonium persulfate (APS) was added dropwise with stirring and heating to a temperature of about 80° C. for about 10 h. The reaction was stopped at about 6 h to conduct a gel-permeation chromatography (GPC) analysis. The GPC analysis of synthetic (P(St-MMA-AA)) reveals the average molecular weight for an approximately 6 h reaction time as shown inFIG.1, with weight-average molecular weight (Mw)=207648, number-average molecular weight (Mn)=32450, and polydispersity index (PD)=6.3. The reaction time at approximately 10 h is shown inFIG.2where Mw=265043, Mn=58169 and PD=4.5.

For the pigment, fly ash-rich carbon was chosen. The fly ash-rich carbon was milled using a Fritsch planetary micro mill Pulverisette 7 using seven balls with diameter of 10 mm at a speed of about 400 rpm for about 20 hours. As a result, the size of the fly ash was reduced to nanometer size for use as a toner pigment.FIG.3andFIG.4are scanning electron microscope (SEM) images of the fly ash before and after grinding, respectively.FIG.5is a graph of the molecular weight distribution after grinding.

Turning toFIG.6, a non-limiting embodiment of a flowchart10illustrating the emulsion aggregation process used in the method of producing toner is shown. In block12, about 3 g of polyethylene wax, about 2 g of the fly ash after milling and about 24.5 g of the [P(St-MMA-AA)] latex are mixed in about 120 mL of deionized water by mechanical stirrer at about 340 rpm for about 15 min at room temperature (between about 20° C. to about 25° C.). Next, in block14, a mechanical mixer was used for about 5 minutes at about 1000 rpm. The mixture was then stirred at about 450 rpm for about 1 hour to achieve a homogeny suspension.

In block16ofFIG.6, about 0.6 g of zinc oxide, about 3 mL of nitric acid, and about 9 mL of deionized water was mixed dropwise into the solution for about 10 minutes, bringing the pH value of the solution to about 2. Here, the zinc oxide serves as a coagulation/thickening agent, with the product in this step changing the viscosity to a gel. Next, in block18, the temperature of the mixture is brought to about 50° C. while the gel is continually stirred manually or automatically. The process is continued for about 30 minutes after which about 1.475 g of Ethylenediaminetetraacetic acid (EDTA) as a chelating agent is added to stop further aggregation. Next, in block20, the temperature of the mixture is increased to about 96° C. over a period of about 30 min and was kept at this temperature for about 2 hours. In block22, the product mixture was neutralized with about 0.1 M sodium hydroxide (NaOH) solution and then cooled down to reach room temperature (between about 20° C. to 25° C.). The final toner product was achieved after centrifugation at about 10,000 rpm for about 10 min, and washing with deionized water was performed, followed by drying in an oven for about 40° C. overnight. Upon completion, the final toner composition was as follows:

Toner particlesPercent by weightPigment (fly ash)6.33%Wax (polyethylene)9.5%Latex (P(St-MMA-AA))77.6%Coagulant agent (zinc oxide)1.9%Chelating agent (EDTA)4.67%

It is to be understood that the toner and method of formation thereof is not limited to the specific embodiments described above, but encompasses any and all embodiments within the scope of the generic language of the following claims enabled by the embodiments described herein, or otherwise shown in the drawings or described above in terms sufficient to enable one of ordinary skill in the art to make and use the claimed subject matter.