FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
and
THE PATENTS RULES, 2005
COMPLETE SPECIFICATION
(See section 10, rule 13)

1. TITLE OF THE INVENTION
“POWDER PAINT FORMULATION AND PROCESS OF PREPARATION THEREOF”

2. APPLICANTS
Name Nationality Address
Mahindra and Mahindra Limited An Indian Company registered under the provisions of the Companies Act, 1956 R&D Center, Auto Sector, 89, M.I.D.C., Satpur, Nashik – 422007, Maharashtra, India
Orchid Polycoats An Indian Partnership Firm B-49, STICE, Musalgaon MIDC, Tal. Sinnar, Dist. Nashik, Maharashtra, India

3. PREAMBLE TO THE DESCRIPTION
PROVISIONAL
The following specification describes the invention COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

POWDER PAINT FORMULATION AND PROCESS OF PREPARATION THEREOF

Field of the invention

The present invention generally relates a chemical composition and a process of preparation thereof. More particularly, the present invention relates to the chemical composition of a powder paint formulation and the process of preparation of the powder paint formulation by using waste paint sludge.

Background of the invention

In an automotive OEM (Original Equipment Manufacturer), a paint shop generates paint sludge during a painting process. As the paint sludge is a hazardous waste material, it affects and pollutes the Green Environment. Hence, the paint sludge needs to be disposed off through Government authorized agency. The OEM has to pay for the disposal of the paint sludge. Thus, the expenditure and the environmental impact of disposing of the paint sludge raise a problem in the automotive industry.

Hence, there is a need to develop an environmentally and economically beneficial process to convert the paint sludge into useful products.

Objects of the invention

An object of the present invention is to provide a powder paint formulation using hazardous and waste paint sludge as one of its ingredients.

Another object of the present invention is to develop a process for preparing the powder paint formulation using hazardous and waste paint sludge as one of its ingredients.
Summary of the invention

Accordingly, the present invention, in one aspect, provides a powder paint formulation. The powder paint formulation (herein after ‘the formulation’) comprises at least one resin. The at least one resin acts as a binder to form a film on a surface of a substrate. The at least one resin is selected from any one of epoxy resin, saturated polyester resin and a combination thereof. The epoxy resin is added at a concentration ranging from 16% by weight to 20% by weight, the saturated polyester resin is added at a concentration ranging from 40% by weight to 45% by weight.

The formulation further comprises at least one pigment to give color to the formulation. The at least one pigment is selected from carbon black that is added at a concentration ranging from 0.5% by weight to 1.5% by weight.

The formulation further comprises at least three additives. The at least three additives are selected from a degassing agent, a flow agent and an anti-corrosive additive. The degassing agent for example benzoin is added at a concentration ranging from 0.5% by weight to 1.5% by weight, the flow agent for example acrylic base polymer is added at a concentration ranging from 0.5% by weight to 1.5% by weight and the anti-corrosive additive for example Zinc based compounds is added at a concentration ranging from 2% by weight to 8% by weight.

The formulation further comprises at least two extenders. The at least two extenders are fillers being selected from paint sludge powder and Barytes. The paint sludge powder is added at a concentration ranging between 15% by weight to 25% by weight and Barytes is added at a concentration ranging between 11% by weight to 15% by weight.

In another aspect, the present invention provides a method for preparing the powder paint formulation.

Brief description of the drawing

The objectives and advantages of the present invention will become apparent from the following description read in accordance with the accompanying drawing wherein,

Figure 1 shows a process of preparing a powder paint formulation by using waste paint sludge, in accordance with the present invention.

Detailed description of the invention

The foregoing objects of the invention are accomplished and the problems and shortcomings associated with the prior art techniques and approaches are overcome by the present invention as described below in the preferred embodiment.

The present invention provides a powder paint formulation and a process for preparation thereof. The powder paint formulation is prepared by the cost effective process utilizing waste paint sludge as one of its ingredients that helps to reduce a major source of chemical waste, thereby providing environmental benefits.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.

The present invention, in one aspect, provides a powder paint formulation. The powder paint formulation (hereinafter “the formulation”) comprises at least one resin, at least one pigment, at least three additives and at least two extenders.

The at least one resin (herein after ‘the resin’) acts as a binders and form a film on a surface (not shown) of a substrate/base (not shown) for example vehicle body shells (not shown) on which the powder coat formulation is applied. The surface of the substrate is made up of a metal such as mild steel, stainless steel, Aluminum and the like. The resin is selected from any one of epoxy resin, saturated polyester resin and a combination thereof where each resin is added separately one after other. However, it is understood that any other resins known in the art can also be used as per various alternate embodiments of the present invention. The epoxy resin imparts the corrosion resistance properties to the formulation and the saturated polyester resin imparts high durability properties to the formulation. In an embodiment, the epoxy resin is added at a concentration ranging from 16% by weight to 20% by weight, preferably 18% by weight of the formulation and the saturated polyester resin is added at a concentration ranging from 40% weight to 45% by weight, preferably 42% by weight of the formulation.

The at least one pigment (herein after ‘the pigment’) is responsible for giving the actual color to the formulation. In an embodiment, the pigment is carbon black added at a concentration ranging from 0.5% by weight to 1.5% by weight, preferably 1% by weight of the formulation. However, it is understood that any other pigments known in the art can also be used as per various alternate embodiments of the present invention.

The at least three additives (herein after ‘the additives’) are responsible for giving specific properties like leveling, flow and the like, to the powder paint sludge. The additives are selected from a degassing agent, a flow agent and an anti-corrosive additive. However, it is understood that any other additive known in the art can be used either alone or in combination with other known additives as per various alternate embodiments of the present invention.

The degassing agent serves to release the gases during the process of preparation of the formulation. In an embodiment, the degassing agent for example benzoin is added at a concentration ranging from 0.5% by weight to 1.5% by weight, preferably 0.8% of the formulation.

The flow agent is added to the formulation to reduce the contact angle between the substrate surface and the coating to be applied which results in a desired good quality finish the of powder coat without any pin holes and creators is achieved. In an embodiment, the flow agent is added at a concentration ranging from 0.5% by weight to 1.5% by weight of the formulation, preferably 1% by weight of the formulation. At a time of application of the formulation on a desired substrate/object; the surface tension of the substrate is generally very high. This high surface tension is reduced by using the flow agent. In an embodiment, the flow agent is acrylic base polymer.

The anti-corrosive additive used in the formulation is generally selected from the commercially available range such as Zinc based compounds in the market. The anti-corrosive additive is added at a concentration ranging from 2% by weight to 8% by weight of the formulation, preferably 5% of the formulation. The anti-corrosive additive is used to accelerate/stimulate the corrosion resistance properties of the formulation and when added with the resins to improve the corrosion resistance life upto 1200 hrs. Thus, the anti-corrosive additive improves the quality of finished powder coated product and also enhances the technical effects of corrosion resistance.

The at least two extenders (herein after ‘the extenders’) are used as fillers in the formulation. In an embodiment, the extenders are selected from Barytes and paint sludge powder. However, other extenders known in the art can also be used as per various alternate embodiments of the present invention. In an embodiment, the concentration of Barytes ranges from 11% by weight to 15% by weight of the formulation, preferably 12.2% by weight of the formulation and the paint sludge powder is added at a concentration ranging from 15% by weight to 25% by weight of the formulation, preferably 20% by weight of the formulation. Specifically, the paint sludge powder forms a major portion of the extenders. The paint sludge powder is obtained by removing thinner and water from the wet paint sludge waste/ paint sludge is in a slurry form of a paint shop using a fractional distillation unit (not shown). The paint sludge is used in the dry powder form as in the powder paint manufacturing industry; all ingredients are required in a powder form (dry particle form) to produce powder paint.

Referring to figure 1, the present invention, in another aspect, provides a process of preparation (100) (hereinafter “the process (100)”) of the powder paint formulation. The process (100) starts at step (10). At step (20), the process (100) includes weighing raw materials such as resin, pigment, additives, extenders as well as paint sludge powder/dried paint sludge.

In step (30), the process (100) involves pre-mixing the raw materials with the dried paint sludge in a hopper (not shown) to produce a mixture.

In step (40), the process (100) involves extruding the mixture at a temperature in a range of 90 degree centigrade to 110 degree centigrade under pressure and at about 500 rpm of the screw speed for duration of about 5 minutes to obtain hot and thick slurry therefrom.

In step (50), the process (100) involves chilling and flaking the slurry by pressing under pressure to obtain uniform chilled flakes.

In step (60), the process (100) involves grinding and air classifying the chilled flakes to obtain a powder of desired uniform coarse texture. Specifically, the chilled flakes are fed in a grinding mill/ machine at a speed of about 7-8 rpm and ground to obtain powder of coarse texture. The time required for grinding depends on the capacity of grinding machine as well as on the kind of coarse texture of the powder that is desired. Further, the powder is air classified by drifting to remove the lighter particles therefrom. This imparts the uniform coarse texture to the final powder. The time required for air classification depends on the quantum of lighter particles available in the final ground material.

In step (70), the process (100) involves sieving the powder of desired uniform coarse texture to obtain non-structured and non-metallic product (70A). If the product obtained after sieving is structured and metallic (70B), then the process (100) at step (70C) involves blending the structured and metallic product (70B) to convert to non-structured and non-metallic product (70A).

In step (80), the process (100) includes packing the non-structured and non-metallic product (70A). The process (100) stops at step (90).

Advantages of the invention

1. The cost of the formulation prepared by the process (100) is reduced by approximately 3.5% (Rs. 3 per kg).
2. The cost of waste paint sludge disposal with the Govt. Agencies is Rs. 15.71 per kg which has totally been eliminated leading to zero investment for disposal. Thus, the saving of Rs.30 lacs per year is achieved by using the process (100)
3. An anti-corrosion life tested as per the salt spray test by using the new formulation increases by 16.66 % (about 1440 hrs) as compared to 1200 hrs in case of existing formulation in the market.
4. Qualitatively the formulation prepared by the process (100) is better than the existing formulation of products available in the market.
5. The specific gravity of the sludge paint powder is less than that of normally used extenders that have specific gravity of 4 which results in reduced overall specific gravity of the formulation and thus improves coverage area of the formulation.
6. The formulation obtained by the process (100) is green innovation and environment friendly.

The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention described in the present embodiment. Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure, or matter. The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention.

We claim:

1. A powder paint formulation comprising:
at least one resin acting as a binder to form a film on a surface of a substrate, the at least one resin being selected from any one of epoxy resin, saturated polyester resin and a combination thereof, wherein the epoxy resin being added at a concentration ranging from 16% by weight to 20% by weight, the saturated polyester resin is added at a concentration ranging from 40% by weight to 45% by weight;
at least one pigment adapted to give color to the formulation, wherein the at least one pigment being selected from carbon black added at a concentration ranging from 0.5% by weight to 1.5% by weight;
at least three additives being selected from a degassing agent, a flow agent and an anti-corrosive additive, wherein the degassing agent being added at a concentration ranging from 0.5% by weight to 1.5% by weight, the flow agent being added at a concentration ranging from 0.5% by weight to 1.5% by weight and the anti-corrosive additive being added at a concentration ranging from 2% by weight to 8% by weight; and
at least two extenders adapted to act as fillers, the at least two extenders being selected from paint sludge powder and Barytes, wherein the paint sludge powder being added at a concentration ranging between 15% by weight to 25% by weight and Barytes being added at a concentration ranging between 11% by weight to 15% by weight.

2. The powder paint formulation as claimed in claim 1, wherein the degassing agent is benzoin.

3. The powder paint formulation as claimed in claim 1, wherein the flow agent is acrylic base polymer.
4. The powder paint formulation as claimed in claim 1, wherein the anti-corrosive additive is selected from Zinc based compounds.

5. A process of preparation of a powder paint formulation, the process comprising the steps of:
weighing raw materials selected from at least one resin, at least one pigment, at least three additives and at least two extenders, wherein the at least one resin being selected from any one of epoxy resin, saturated polyester resin and a combination thereof, the at least one pigment being selected from carbon black, the at least three additives being selected from a degassing agent, a flow agent and an anti-corrosive additive and the at least two extenders being selected from paint sludge powder and Barytes;
pre-mixing the raw materials with the dried paint sludge powder in a hopper to produce a mixture;
extruding the mixture at a temperature ranging from 90 degree centigrade to 110 degree centigrade under pressure and at a speed of about 500 rpm for a duration of about 5 minutes to obtain hot and thick slurry therefrom;
chilling and flaking the extruded mixture to obtain uniform chilled flakes;
grinding and air classifying the chilled flakes at a speed of about 7-8 rpm to obtain a powder of desired uniform coarse texture; and
sieving the powder of desired uniform coarse texture to obtain a non- structured and non-metallic product followed by packaging thereof.

6. The process as claimed in claim 5 comprises a step of blending to convert a structured and metallic product obtained after sieving into the non- structured and non-metallic product followed by packaging thereof.

Dated this 09th day of February, 2016
Priya Pandey
(Agent for Applicant)