How to Clean Car Interior Trim, Leather, and Upholstery with Koch Chemie

Interior detailing is where most enthusiasts underinvest — and where the most damage is done by using the wrong products. Leather, Alcantara, fabric upholstery, and hard plastic trim all have different surface structures and different tolerances for chemistry. Using a single all-purpose cleaner on everything is a shortcut that leads to cracked leather, crushed Alcantara pile, and faded trim.

Here's a systematic approach using Pol Star for soft surfaces and Green Star for hard trim.

Understanding Your Surfaces

Before reaching for any product, identify what you're cleaning:

• Leather seats: Smooth, coated surface. Needs a pH-neutral cleaner that won't strip the protective topcoat.
• Alcantara / suede: Microfiber material. Extremely sensitive to harsh chemistry and aggressive agitation.
• Fabric upholstery and carpets: Porous, fiber-based. Requires a foaming cleaner that can penetrate and be extracted.
• Hard plastic trim and dashboards: More tolerant of diluted alkaline cleaners, but gloss surfaces can scratch easily.

Cleaning Leather and Alcantara with Pol Star

Pol Star is a pH-neutral cleaner formulated specifically for leather, Alcantara, and textiles. Its fine-pored foam structure lifts dirt from deep within fibers without saturating the material or leaving water marks.

1. Spray Pol Star directly onto the surface or onto a soft detailing brush.
2. Agitate gently in small circular motions — use a soft-bristle brush for fabric, a microfiber cloth for leather.
3. For Alcantara, always brush in the direction of the pile to avoid crushing it.
4. Remove the lifted dirt with a damp microfiber cloth or a wet/dry vacuum.
5. Allow the surface to dry fully before applying any conditioner or protectant.

Pol Star's formula also contains a protective agent that helps surfaces resist re-soiling — a meaningful benefit for high-contact areas like seat bolsters and headrests.

Cleaning Hard Trim and Plastics with Green Star

Green Star is a concentrated alkaline universal cleaner that handles the heavier soiling found on door jambs, footwells, dashboard plastics, and center consoles. Dilute appropriately for interior use — typically 1:20 to 1:50 for sensitive surfaces, stronger for heavily soiled hard plastics.

1. Dilute Green Star in a spray bottle at the appropriate ratio.
2. Spray onto the surface and agitate with a detailing brush or microfiber cloth.
3. Wipe clean with a damp microfiber cloth.
4. For textured plastics, a soft detailing brush helps work the product into the grain.

Do not use Green Star at high concentrations on leather or Alcantara. Its alkalinity is effective on hard surfaces but too aggressive for delicate soft materials — that's what Pol Star is for.

Sequence for a Full Interior Detail

Work top-to-bottom, dry-to-wet: headliner → dashboard → door cards → seats → carpets → footwells. This prevents drips from contaminating already-cleaned surfaces.

Shop Pol Star → | Shop Green Star →