Surface Finishes for Custom Plastic & Rubber Parts
We provide diverse surface solutions for both your molds and the custom plastic and rubber parts they produce. From texturing and polishing mold cavities to applying secondary finishes on final components, we ensure your products meet exact aesthetic requirements.
Our post-processing capabilities include painting, printing, plating, laser engraving, and more. When you inquire about a new project, we carefully listen to your visual and functional needs to recommend the most suitable and feasible finishing process.
With a wide range of appearance options, we are equipped to satisfy the diverse demands of various industries and help your product make the right impression.
Surface Finishing options For Plastic Parts
Standard Type
Common Grade/Value
Surface Effect Description
Common Terminology
Typical Applications
SPI
A-1
Optical mirror finish, flawless.
#1 Mirror, Optical Polish
Lenses, light guide plates, high-gloss black appliances , premium cosmetic packaging
SPI
A-2
Very high gloss, with minimal fine lines.
#2 Polish, High Gloss
Appliance high-gloss surfaces, transparent parts, mobile phone housings (glossy)
SPI
A-3 / B-1
High gloss, with slight stone lines.
#3 Polish, Semi-Gloss
General high-quality appearance parts
SPI / VDI
B-2 / B-3
VDI 18~21
Fine, non-directional matte surface.
Satin Finish, Dulling
Hiding flow lines, internal parts requiring a uniform appearance
SPI / VDI
C-1 / C-2
VDI 24~30
Uniform, fine stippled texture.
Shot Blast, EDM Texture
General internal structural parts, masking machining marks
VDI / Texture
VDI 30~45+
Distinct leather, grained, or textured pattern.
Texture, Graining, Etching
Automotive interiors (leather grain), tool handles (diamond pattern), electronics (fine texture)
Non-Cosmetic
API-F0
Non-cosmetic; as-molded finish. All tool marks (EDM, machining lines) may be visible. Lowest cost option.
As-molded, No Finish
Internal structural components, completely hidden parts with purely functional requirements.
Non-Cosmetic
API-F1
Non-cosmetic; uniform EDM texture is permissible. Sharp burrs are typically removed.
EDM Texture Acceptable
Internal functional parts where a uniform, non-reflective surface is adequate.
Low Cosmetic
API-F2
Low-cosmetic; obvious tool marks are removed, but a uniform polished or textured finish is not required.
De-burred, Basic Smoothing
Low-priority internal parts where gross tool marks are undesirable, or occasionally glimpsed interior areas.
secondary processes for plastic Parts
- Painting / Coating
- Plating
- Printing(Screen Printing and Pad Printing)
- Hydrographics / Water Transfer Printing
- Heat Transfer Printing
- Laser Engraving / Marking
Surface Finishing options for Rubber Parts
Mold Finishing
Purpose
Suitable Product Types
Hard Chrome Plating
Provides excellent non-stick release performance, ensuring viscous rubber parts demold smoothly without damage. Resists abrasion and chemical corrosion.
The industry standard for nearly all rubber types, including Silicone (LSR & HCR), EPDM, NBR, FKM. Essential for production efficiency.
Shot Blasting
1. Creates a uniform matte or satin finish. 2. Aids in venting trapped air from the mold cavity to prevent defects.
1. Parts requiring a matte, anti-slip surface (e.g., seals, grips).
2. For a uniform non-glossy appearance.
3. Typically combined with Hard Chrome Plating.
Polishing
Gives the rubber product a smooth, high-gloss, or even transparent appearance. The smooth surface also assists with demolding.
1. Transparent rubber parts (e.g., transparent silicone pads).
2. Consumer electronics components requiring a high-gloss surface.
3. Runner and gate systems within the mold to reduce flow resistance.
secondary processes for Rubber Parts
Finishing process
Description & Purpose
Typical Applications
Silicone Feel Agent Spray
Spraying a specialized feel agent onto the surface to eliminate the inherent slight tackiness of silicone, providing a dry and silky-smooth touch.
Consumer electronics grips, wearable device casings, non-medical seals.
Inkjet / Laser Marking
Permanently marking logos, batch numbers, QR codes, etc., onto the product surface for identification and traceability.
Medical catheters (gradations), electronic seals (serial numbers), consumer goods (branding).
Plasma Treatment
| Bombarding the surface with plasma to increase the surface energy of silicone, significantly improving its adhesion to adhesives and coatings. |
Pre-treatment before bonding silicone to other materials like plastics or metals.
Silicone Bonding
Using specialized silicone adhesive to bond silicone parts to other materials. Typically requires prior Plasma Treatment.
Fixing waterproof seals, joining protective cover sections, medical device assembly.
Post-Curing
Baking molded silicone parts in an oven to remove residual volatiles, enhancing material properties and safety ratings.
Food-grade/medical-grade silicone products (odor removal), high-performance seals.
Trimming / Deburring
Removing molding flash and burrs via manual, cryogenic (embrittlement), or mechanical methods.
Nearly all compression molded and LSR parts, e.g., O-rings, seals, complex silicone products.
Continuous Vulcanization
Passing extruded profile through a long heated vulcanization tunnel (e.g., hot air, microwave) for continuous production.
Continuous production of sealing strips, cables.
Cutting & Splicing
Cutting continuous extruded profiles to specified lengths or joining ends via vulcanization to form loops.
extruded tube
Tip Forming / Molding
Molding specific shapes (e.g., plugs, custom connectors) onto the ends of extruded profiles for functional integration.
Sealing ends of door/window seals, forming connectors for automotive air ducts.
| Insert Molding / Overmolding |
Placing metal or other components as inserts into the mold, then injecting LSR around them to form a single integrated part.
Kitchenware (overmolding metal knife handles), electronic connectors (sealing plastic housings).