One of vaping’s most popular looks: gradient colors never go out of style

Throughout the evolution of e-cigarette products, whether they were once popular or are currently trending, there is one type of appearance that is often seen: the gradient color design.

Gradient colors can transition from one color to another or vary in shades of a single color.

With rich color layers and a sense of flow, the product surface presents a high-end, refined texture, adding unique visual appeal and artistry to the product.

The long-lasting popularity of gradient colors can be attributed to two main reasons: they are visually appealing and the manufacturing process is stable and cost-effective.

There are many processes that can achieve gradient colors, including anodizing, spraying, PVD coating, UV transfer, silk printing, and color printing, but not every process can achieve a balance of stable yield and cost advantages.

In the e-cigarette industry, the commonly used processes for gradient colors are anodizing and spraying, while there are also new gradient color processes available for reference, such as gradient injection molding.

1. Anodizing

Anodizing involves forming a layer of oxide film on the surface of metals. Pure anodizing includes only the process of generating the anodized film.

If coloring the metal is required, it must undergo dyeing and sealing to achieve the coloring effect; this process is suitable for aluminum alloy parts.

Gradient colors are achieved by controlling the dyeing time in the dye bath, where the dye enters the molecular gaps of the oxide film during the dyeing process. The longer the dyeing time, the more dye enters, resulting in a deeper color.

By computer controlling the time the parts need to stay in the dye, such as gradually withdrawing the parts from the dye, a uniform gradient color effect can be achieved.

The process flow mainly includes: degreasing → alkaline etching → chemical polishing → neutralization → anodizing → dyeing → sealing → hot water washing → drying.

Anodizing, Jingkang Technology

Gradient color, Nichia Technology

2. Spraying (also known as spray painting)

Spraying is a processing method that atomizes paint using a spray gun and coats it onto the surface of an object.

It can obtain coatings with wear resistance, corrosion resistance, thermal insulation, conductivity, insulation, sealing, lubrication, and other special physical and chemical properties on various substrates.

The application range is very broad and belongs to traditional processes.

Gradient color spraying utilizes spraying equipment with two or more colors of paint, and by modifying the equipment structure, one color can gradually transition to another, creating a new decorative effect. The equipment operation is relatively simple and efficient.

Simple gradient color spraying can be achieved, making it easy to mass-produce with high yield.

During the spraying process, multiple layers of color are applied (3-4 layers), with the core being to control the thickness of the coating, where each layer transitions from one color to another.

In addition, the choice of paint is also crucial; the selected paint must not only provide wear and corrosion resistance to the plastic shell surface but also have decorative effects, and the brightness of the color is also important.

The process flow mainly includes: substrate treatment → sequential spraying of functional primer, gradient paint, and gloss paint → baking/self-drying.

3. Gradient injection molding

Gradient injection molding is a process recently introduced by Aborg, which uses a two-color molding method to inject two different colored materials through precise injection control of the injection machine and mold, achieving gradient colors or multi-layer co-injection products.

However, there is currently no more information available regarding the application of this process in the e-cigarette industry. This is a brief introduction for interested readers.

Gradient injection molding, Aborg

4. Others

Of course, there are many other processes that can achieve gradient colors, such as PVD coating, UV transfer, silk printing, color printing, etc.; different processes are suitable for different needs. For large-scale production, spraying, anodizing, and injection molding are more suitable; for short-term batch production with high efficiency, UV printing can be considered.