3Finish states
3–8 GUMIC gloss at 60°
PP/TPOAdhesion primer
3C2BFull paint
ΔE ≤1.0Color tolerance
01 — Overview

Finish States at a Glance

The same exterior cover in textured molded-in color and painted gloss black
The same exterior cover in textured molded-in color and painted gloss black
StateWhat you receiveTypical useGloss at 60°
Molded-in color (MIC)Part in the material’s own color: natural, black, greyLow cost; customer paints; unpainted textured parts3–8 GU
PrimedPart with surface preparation and primer (PP/TPO adhesion primer for polyolefins)Body shops and installers who paint to the car’s colorPrimer surface
Fully painted3C2B color + clear, or paint-free molded gloss or matteReady to fitBy finish, e.g. ≥90 GU gloss black

Key facts about finish states at Yirox

  • Three states: molded-in color, primed, or fully painted.
  • PP and TPO parts get an adhesion primer before painting.
  • Molded-in color parts are typically 3–8 GU at 60°.
  • Made in our IATF 16949 and ISO 9001 certified factory of about 20,000 m² in Wuxi, China.
  • 42 injection molding machines from 90 to 2,500 t, including 3 two-shot machines.
  • Two paint lines with a 3C2B system; painted color held to ΔE*ab ≤1.0.
02 — Encyclopedia

What Is Molded-in Color?

Molded-in color (MIC) means the color is in the plastic itself, added as a pigment or masterbatch before molding, so the part needs no paint. MIC parts cannot peel or chip to a different color, and a scratch shows the same color underneath. We supply MIC parts in the material’s natural color or in black, grey and other colors, in PP, TPO, ASA and other materials.

Natural, black and grey resin pellets with molded sample parts made from each
Natural, black and grey resin pellets with molded sample parts made from each

MIC is used for unpainted textured parts such as fender flares and cladding, and for parts the customer will paint later. With UV-stable materials such as ASA, PP and TPO, MIC parts can stay unpainted on the vehicle.

03 — Encyclopedia

What Is a Primed Bumper or Primed Part?

A primed part has been cleaned, prepared and coated with a primer, but not with color. Primed bumpers and trim are popular with body shops because they can be painted to the exact color of the car. Primer improves paint adhesion and gives a uniform surface for the color coat.

Grey primed front bumper, lower section close-up
Grey primed front bumper, lower section close-up

On PP and TPO parts, we use a PP/TPO-specific adhesion primer, because polyolefins have a low surface energy that ordinary paint does not bond to. Primed parts are also ready for water transfer printing.

04 — Encyclopedia

Painted vs Unpainted Bumper

Three fender flares: raw molded-in color, grey primed and painted gloss black
Three fender flares: raw molded-in color, grey primed and painted gloss black
PointUnpainted (MIC)PrimedFully painted
PriceLowestMediumHighest
Ready to fitYes, if the look suitsNo, needs paintingYes
Color match to carNoYes, by the painterYes, to a color standard
Scratch visibilityLow, same color underneath—Depends on finish
Best forWork vehicles, textured parts, low costBody shops, collision repairRetail and dealer accessories
05 — Encyclopedia

Full Paint and Paint-free Gloss or Matte

For ready-to-fit parts, we paint in our 3C2B system (base, color and clear) with a total film of 35–50 μm, color ΔE*ab ≤1.0 and cross-hatch adhesion 0–1. We can also mold paint-free high-gloss or matte parts, where the mold surface sets the finish. See piano black and matte black.

Robots spray-painting bumper covers in a paint booth
Robots spray-painting bumper covers in a paint booth
06 — Service

How Each State Is Produced

  1. 01

    Molding

    Parts are molded in the chosen material and color.

  2. 02

    Inspection

    Surface and dimensions are checked before finishing.

  3. 03

    Surface preparation

    Parts for primer or paint are cleaned and pre-treated.

  4. 04

    Primer

    A primer is applied; PP and TPO get an adhesion primer.

  5. 05

    Color and clear

    Painted parts receive color and clearcoat in a 3C2B system.

  6. 06

    Packing

    Show surfaces are protected for shipping.

07 — Service

Choosing the Right State

Finished black plastic bumpers and body kit parts on storage racks
Finished black plastic bumpers and body kit parts on storage racks

Choose MIC

when the part is textured, unpainted on the vehicle, or cost is the priority.

Choose primed

when the customer or body shop will paint to the car’s color.

Choose fully painted

when the part must arrive ready to fit in a set color or finish.

Choose paint-free gloss or matte

when a black part needs a finished look without paint cost.

08 — Service

Parts We Supply Primed, Painted or MIC

Not sure if you need primed or painted parts?Tell us who fits and paints the part and we will recommend primed, painted or molded-in color.

09 — Capability

Our Finishing Capability

Bumpers and exterior parts on the production line in the Yirox factory in Wuxi
Bumpers and exterior parts on the production line in the Yirox factory in Wuxi

Two paint lines

L1 rotary automatic (24 stations) and L2 overhead conveyor with 4 manual touch-up stations.

Clean rooms

Spray booths ISO 8, flash-off and oven ISO 7.

Bake

60 °C × 10 min pre-bake and 80 °C × 30 min topcoat bake.

Checks

Gloss (BYK micro-TRI-gloss), color (X-Rite Ci64), film thickness (BYK 8500), cross-hatch adhesion.

10 — Service

What to Send for a Quote

Inspector measuring a gloss black exterior part on a checking fixture
Inspector measuring a gloss black exterior part on a checking fixture
  • 3D CAD or a sample part
  • State: MIC, primed or painted; color and gloss
  • Material, if specified
  • Annual quantity and order size

Ready to quote primed or painted parts?Send drawings or a sample with the quantity and we will quote a primed bumper or painted parts.

What Buyers Say About Our Materials and Finishes

Buyers on material, finish and quality questions we worked through with them.

“Gloss black parts are unforgiving. Small differences become obvious when they’re installed next to each other. We wanted more than a visual check, and the colour inspection records gave our quality team something objective to work with.”
Quality Assurance ManagerAutomotive Surface Finishing
“The first order tells you whether a supplier can make the product. The second and third tell you whether they can maintain the same standard. For our team, consistent finish and packing across repeat orders are what make a supplier worth keeping.”
Automotive Parts DistributorLong-Term Supply Program

Names and companies withheld at the customer’s request.

13 — FAQ

FAQ

What is molded-in color?

The color is in the plastic itself, so the part needs no paint and cannot peel. We supply natural, black, grey and other colors.

What is a primed bumper?

A bumper that has been prepared and coated with primer, ready to be painted to the car’s color by a body shop.

Should I buy a painted or unpainted bumper?

Unpainted MIC parts cost least; primed parts let a painter match the car; painted parts are ready to fit.

Why do PP bumpers need a special primer?

PP and TPO have low surface energy. A PP/TPO adhesion primer makes paint bond properly.

Can primed parts be hydro dipped?

Yes. Our primed parts are ready for water transfer printing.

What is the minimum order quantity?

We offer low MOQ on selected items. The quantity is confirmed in your quote.

Get a Quote

Send your drawing or a sample and tell us the finish state you need. We will reply with a quote.

Request a Quote

Tell us the part, vehicle and quantity. An engineer replies by email.

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