TECHNICAL FIELD

[0001] The present disclosure relates to water-based primers and methods for synthesizing the same, particularly relates to conversion coating compositions and methods for synthesizing the same, and more particularly relates to a rust converter coating composition and a method for synthesizing the same.

BACKGROUND ART

[0002] Iron or steel surfaces may corrode and be covered with rust. Corrosion, either in the form of a light rust film or in the form of a heavier scale on the metal surface is undesirable. Different methods and techniques may be utilized for protecting metallic surfaces from corrosion, especially metallic surfaces that are exposed to adverse weather conditions, such as rain, salt mist, and direct sunlight. Surface treatments, such as anti-corrosion coatings may be applied to the surface and if these coatings cover the entire surface without any defects, they may stop or retard corrosion.

[0003] Rust converters are among surface treatments that may be applied directly to a rusty surface to convert the rust on the surface to stable chemical compounds. Most rust converters utilize tannic acid or tannin as their main ingredient. Tannin is an organic acid that may be extracted from different species of plant. When tannin is applied on a rusty surface, it reacts with the iron ions and forms ferric tannate, which is a stable black substance that provides a protective coating on the surface. There is a need for rust converters with improved anti corrosion properties that may provide a suitable primer for both oil- and epoxy-based paints.

SUMMARY OF THE DISCLOSURE

[0004] This summary is intended to provide an overview of the subject matter of the present disclosure, and is not intended to identify essential elements or key elements of the subject matter, nor is it intended to be used to determine the scope of the claimed implementations. The proper scope of the present disclosure may be ascertained from the claims set forth below in view of the detailed description below and the drawings.

[0005] According to one or more exemplary embodiments, the present disclosure is directed to a method for synthesizing a water-based primer. The exemplary method may include preparing a tannic acid powder mixture by mixing tannic acid powder with silica nanoparticles and zinc oxide nanoparticles, preparing a base polymer solution by mixing an acrylic resin, water, a pigment, and a filler, and mixing the tannic acid powder mixture and the base polymer solution with a predetermined ratio.

[0006] In an exemplary embodiment, preparing the tannic acid powder mixture may include mixing tannic acid powder with silica nanoparticles and zinc oxide nanoparticles, the silica nanoparticles with a concentration in a range of 0.1 wt.% to 0.2 wt.% based on total weight of the tannic acid powder mixture.

[0007] In an exemplary embodiment, preparing the tannic acid powder mixture may include mixing tannic acid powder with silica nanoparticles and zinc oxide nanoparticles, the zinc oxide nanoparticles with a concentration in a range of 1 wt.% to 1.5 wt.% based on total weight of the tannic acid powder mixture.

[0008] In an exemplary embodiment, preparing the tannic acid powder mixture may include mixing tannic acid powder with silica nanoparticles with an average particle size between 30 nm and 35 nm and zinc oxide nanoparticles with an average particle size between 35 nm and 50 nm.

[0009] In an exemplary embodiment, preparing the tannic acid powder mixture may include mixing tannic acid powder with silica (Si02) nanoparticles and zinc oxide (ZnO) nanoparticles in a mixer at a temperature in a range of 20 oC to 25 oC with a stirrer speed in a range of 750 rpm to 900 rpm.

[0010] In an exemplary embodiment, preparing the base polymer solution may include mixing an acrylic resin with a concentration in a range of 50 wt.% to 53 wt.% of total polymer solution, water with a concentration in a range of 7 wt.% to 10 wt.% of total polymer solution, a pigment with a concentration in a range of 3 wt.% to 5 wt.% of total polymer solution, and a filler with a concentration in a range of 35 wt.% to 40 wt.% of total polymer solution.

[0011] In an exemplary embodiment, preparing the exemplary base polymer solution may further include adding a rheological additive to the base polymer, the rheological additive with a concentration in a range of 1 wt.% to 2.5 wt.% of total polymer solution.

[0012] In an exemplary embodiment, preparing the base polymer solution may include mixing the acrylic resin, water, the pigment, and the filler in a mixer with a stirrer speed of 750 rpm to 900 rpm at a temperature in a range of 20 oC to 25 oC. [0013] In an exemplary embodiment, mixing the tannic acid powder mixture and the base polymer solution with a predetermined ratio may include mixing the tannic acid powder mixture and the base polymer solution with a powder mixture-to-polymer solution ratio between 0.03 and 0.05.

[0014] In an exemplary embodiment, mixing the tannic acid powder mixture and the base polymer solution with a predetermined ratio may include mixing the tannic acid powder mixture and the base polymer solution at a pH in a range of 4 to 6.

[0015] According to one or more exemplary embodiments, the present disclosure is directed to a water-based primer that may include tannic acid with a concentration in a range of 1 wt.% to 2.5 wt.% of total water-based primer, Si02 nanoparticles with a concentration in a range of 0.1 wt.% to 0.2 wt.% of total water-based primer, ZnO nanoparticles with a concentration in a range of 1 wt.% to 1.5 wt.% of total water-based primer, an acrylic resin with a concentration in a range of 50 wt.% to 53 wt.% of total water-based primer, a pigment with a concentration in a range of 3 wt.% to 5 wt.% of total water-based primer, and a balancing amount of a filler.

[0016] In an exemplary embodiment, the exemplary water-based primer may further include 1 wt.% to 2 wt.% of a derivative of bentonite clay. In one or more exemplary embodiments, the pigment may be T1O2 and the filler may be BaSC .

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawing figures depict one or more implementations in accord with the present teachings, by way of example only, not by way of limitation. In the figures, like reference numerals refer to the same or similar elements.

[0018] FIG. 1 illustrates a method for synthesizing a water-based primer, consistent with one or more exemplary embodiments of the present disclosure.

DESCRIPTION OF EMBODIMENTS

[0019] In the following detailed description, numerous specific details are set forth by way of examples to provide a thorough understanding of the relevant teachings related to the exemplary embodiments. However, it should be apparent that the present teachings may be practiced without such details. In other instances, well known methods, procedures, components, and/or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings.

[0020] The following detailed description is presented to enable a person skilled in the art to make and use the methods and devices disclosed in exemplary embodiments of the present disclosure. For purposes of explanation, specific nomenclature is set forth to provide a thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that these specific details are not required to practice the disclosed exemplary embodiments. Descriptions of specific exemplary embodiments are provided only as representative examples. Various modifications to the exemplary implementations will be plain to one skilled in the art, and the general principles defined herein may be applied to other implementations and applications without departing from the scope of the present disclosure. The present disclosure is not intended to be limited to the implementations shown, but is to be accorded the widest possible scope consistent with the principles and features disclosed herein.

[0021] The present disclosure is directed to a water-based primer that may function as a rust converter. The exemplary water-based primer may include tannic acid, which is capable of reacting with iron oxide (rust) and chemically converting it to iron tannate, a dark-colored stable material. The exemplary water-based primer may further include an organic polymer that may provide a protective layer on the surface to prevent further corrosion. The exemplary water-base primer may further include zinc oxide nanoparticles to improve the anti-corrosion properties of tannic acid and silica nanoparticles to prevent agglomeration. In exemplary embodiments, when the exemplary water-based primer is applied on a rusty surface, a black stable polymeric coating may be created on the previously rusty surface and this black stable polymeric coating may serve as either a final protective layer or a primer layer for both oil- and epoxy-based paints. The exemplary water-based primer may be applied on surfaces that are exposed to adverse weather conditions to protect the surface from rain, salt mist, and direct sunlight. In exemplary embodiments, the rusty surface on which the exemplary water-based primer is to be applied must be prepared by removing large rust scale to remove any loose or flaking rust. However, it should be understood that not all the rust on the surface is removed before applying the exemplary water-based rust converter.

[0022] FIG. 1 illustrates a method 100 for synthesizing a water-based primer, consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, method 100 may include a step 102 of preparing a tannic acid powder mixture including nanoparticles by mixing tannic acid powder with nanosilica particles and zinc oxide nanoparticles, a step 104 of preparing a base polymer solution by mixing an acrylic resin, water, a pigment, and a filler, and a step 106 of mixing the tannic acid powder mixture and the base polymer solution with a predetermined ratio.

[0023] In an exemplary embodiment, step 102 of preparing a tannic acid powder mixture including nanoparticles may include mixing tannic acid powder with silica (SiC ) nanoparticles and zinc oxide (ZnO) nanoparticles in a mixer at a temperature in a range of 20 °C to 25 °C with a stirrer speed in a range of 750 rpm to 900 rpm. In an exemplary embodiment, the prepared tannic acid powder mixture may include 0.1 wt.% to 0.2 wt.% SiC nanoparticles, 1 wt.% to 1.5 wt.% ZnO nanoparticles and a balancing amount of tannic acid. In an exemplary embodiment, Si0 ₂ nanoparticles may have an average size between 30 nm and 35 nm and ZnO nanoparticles may have an average size between 35 nm and 50 nm. Mixing ZnO nanoparticles with the tannic acid powder may help improve anti-corrosive properties of tannic acid and mixing Si02 nanoparticles may help prevent agglomeration in the final product.

[0024] In an exemplary embodiment, step 104 of preparing a base polymer solution may include mixing an acrylic resin, water, a pigment such as titanium dioxide (Ti0 ₂ ), and a filler such as BaS0 ₄ in a mixer with a stirrer speed of 750 rpm to 900 rpm at a temperature in a range of 20 °C to 25 °C. In exemplary embodiments, the prepared base polymer solution may include 50 wt.% to 53 wt.% acrylic resin, 3 wt.% to 5 wt.% pigment, 35 wt.% to 40 wt.% filler, and 7 wt.% to 10 wt.% water. In an exemplary embodiment, step 104 of preparing a base polymer solution may further include adding a small amount (between 1 wt.% and 2.5 wt.%) of rheological additives such as derivatives of bentonite clay to the base polymer solution. In exemplary embodiments, such rheological additives may function as anti-settling agent in the final formulation of the exemplary water-based primer. In exemplary embodiments, step 104 of preparing a base polymer solution may further include adding an anti-mold agent and an anti-foam agent to the base polymer solution.

[0025] In an exemplary embodiment, step 106 of mixing the tannic acid powder mixture and the base polymer solution with a predetermined ratio may include mixing the tannic acid powder and the base polymer solution with a powder-to-solution ratio between 0.03 and 0.05. In an exemplary embodiment, mixing the tannic acid powder and the base polymer solution may be carried out at a pH in a range of 4 to 6 and a temperature in a range of 20 °C to 25 °C. [0026] In an exemplary embodiment, the water-based primer prepared by method 100 may include 3 wt.% to 5 wt.% tannic acid, 0.1 wt.% to 0.2 wt.% S1O2 nanoparticles, 1 wt.% to 1.5 wt.% ZnO nanoparticles, 50 wt.% to 53 wt.% acrylic resin, 3 wt.% to 5 wt.% T1O2, 7 wt.% to 10 wt.% water, and 25 wt.% to 35 wt.% BaS0 ₄ based on the total weight of the exemplary water-based primer.

[0027] In an exemplary embodiment, the water-based primer prepared by method 100 may include 3 wt.% to 5 wt.% tannic acid, 0.1 wt.% to 0.2 wt.% S1O2 nanoparticles, 1 wt.% to 1.5 wt.% ZnO nanoparticles, 50 wt.% to 53 wt.% acrylic resin, 3 wt.% to 5 wt.% T1O2, 7 wt.% to 10 wt.% water, 25 wt.% to 35 wt.% BaS0 ₄ , lwt.% to 2 wt.% derivatives of bentonite clay, and 1 wt.% to 3 wt.% of other additives such as anti-mold and anti-foam agents, based on the total weight of the exemplary water-based primer.

[0028] According to one or more exemplary embodiments, the water-based primer prepared by method 100 may be applied on a rusty surface and may react with rust and create a dark- colored inert coating or primer that may further be painted on. The dark-colored inert coating created by the exemplary water-based primer on the rusty surface may help conceal the rusty part and prevent further corrosion of the surface. In an exemplary embodiment, the water-based primer prepared by method 100 may be applied on the rusty surface by either a brush or a roller.

[0029] According to one or more exemplary embodiments, before applying the exemplary water-based primer on a surface, the surface needs to be prepared. In an exemplary embodiment, preparing the surface may include removing large rust and scale particles by a stiff-bristled brush, hammer, or sandpaper, and optionally degreasing and drying the surface.

EXAMPLE

[0030] In this example, a water-based primer composition is prepared consistent with one or more exemplary embodiments of the present disclosure. In order to prepare the water-based primer of the present example, a tannic acid powder including 98.5 wt.% of tannic acid, 1 wt.% of ZnO nanoparticles, and 0.5 wt.% of S1O2 nanoparticles was mixed with a base polymer solution including 30 wt.% acrylic resin emulsion, 40 wt.% T1O2, 20 wt.% water, and 10 wt.% BaSCL. The tannic acid powder was mixed with the base solution with a powder-to-solution ration of 4 wt.% to 5 wt.% at a pH range of 4 to 6 . [0031] While the foregoing has described what are considered to be the best mode and/or other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that the teachings may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all applications, modifications, and variations that fall within the true scope of the present teachings.

[0032] Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain.

[0033] The scope of protection is limited solely by the claims that now follow. That scope is intended and should be interpreted to be as broad as is consistent with the ordinary meaning of the language that is used in the claims when interpreted in light of this specification and the prosecution history that follows and to encompass all structural and functional equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of Sections 101, 102, or 103 of the Patent Act, nor should they be interpreted in such a way. Any unintended embracement of such subject matter is hereby disclaimed.

[0034] Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims.

[0035] It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein. Relational terms such as first and second and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms“comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by“a” or“an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0036] The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various implementations. This is for purposes of streamlining the disclosure, and is not to be interpreted as reflecting an intention that the claimed implementations require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed implementation. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.

[0037] While various implementations have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more implementations and implementations are possible that are within the scope of the implementations. Although many possible combinations of features are shown in the accompanying figures and discussed in this detailed description, many other combinations of the disclosed features are possible. Any feature of any implementation may be used in combination with or substituted for any other feature or element in any other implementation unless specifically restricted. Therefore, it will be understood that any of the features shown and/or discussed in the present disclosure may be implemented together in any suitable combination. Accordingly, the implementations are not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.