The objective of this guide
To provide a guide that roto molded plastic manufacturers can use and refer to when considering branding with confidence on plastic parts. This will help for both existing and new parts.
Considerations include, but not limited to the following in this design guide as following.
- Material types best suited for branding
- Colour options, special effects, and UV stability
- Molding types i.e., roto, injection, blow-molding
- Indicative costs and what to expect
- Mold surface textures and shape
- Transparency and opacity of graphics
- Resolution for prints, process vs spot colour
- Inspiration in images
How to Start a Branding Project for Roto Moulded Parts
Starting up a new branding project requires good preparation. We would like to share the knowledge gained through the previous 20+ years of experience, so have prepared a shortlist of 5 essential steps, outlined in tangible ways for hopefully immediate effect. We are assuming your, or your clients’ corporate brand name, logo or specific design is already finalized, ready to use on your products.
Good luck with starting up your project!
SECTION 1: Product design and mold detail
Surface texture
Parts may feature anything from a high-polish finish to deep shot-peened texture, dependent on the desired aesthetics of your customer. It should be well noted that a flat smooth area works best for any in-mold or post-mold graphic system, especially post mould, heat-transfer type graphics. Any prevalent texture will affect the application time i.e., more texture = more time required. Graphics will also take on the surface texture, so consider smooth surface for maximum WOW-effect of your branding. Example below shows how you can easily achieve a graphic ready surface.
Product shape & thickness
Part curvature or contours will affect the shape and size of graphic formation, and where they are located on the part. Smaller graphics with less surface area will be less prone to wrinkle or distort. Part thickness can influence your graphic – aim for 6mm (0.25”) minimum for heat-transfer type graphics, especially for larger designs as these require more heat distribution over a greater area. Application to thicker or more stable surfaces walls i.e., ribbed will ensure best results. Thinner-walled parts are likely to warp, creating application difficulties, therefore are not well suited for larger graphics.
Brand positioning & purpose
Positioning your brand for maximum effect needs to be well thought out. Is this your logo, a tracking reference or important safety information? What is going to be the most logical visual area also interprets to how are you going to place the graphics in mold i.e., is their mold access to allow application, or is the part wall thick enough or well-formed in the #1 area to support the graphics? Consider #2 or even #3 application positions for each for prototypes.
Plastic types & molding processes
Why nothing sticks to plastic has its purpose right, like water off a duck’s back! This is also why one label will stick to aluminum or glass, with surface tension levels of 500-1000 mN/m, but not to your plastic product, this is all to do with surface tension. The below chart shows these respective surface tension levels, and suitable graphic types from PSI Brand, best suited for plastic types known in rotomoulding.
| Surface Type | Surface Tension (mN/m) | INMOULD Original | INMOULD X-Treme | POST MOULD | VINYL DECAL |
| Polyethylene (PE) | 31 | Yes¹ | Yes¹ | Yes | Yes |
| Polypropylene (PP) | 31 | Yes | Yes | No | Yes |
| Polyvinyl chloride (PVC) | 39 | Yes | No | No | Yes |
| Acrylonitrile butadiene styrene (ABS) | 42 | Yes | No | Yes | Yes |
| Polycarbonate (PC) | 42 | Yes | No | No | Yes |
| Nylon-6,6 | 43 | Yes | No | Yes | Yes |
| Polyurethane (PU) | 43 | Yes | No | No | Yes |
| Polyester (PET) | 43 | Yes | No | No | Yes |
¹Not suited for XL-PE
In summary
We hope you found this guide to product design and mold detail useful in maximising your branding opportunities. To see more on Steps 2 through to 5 in the complete design guide, go to next section
