The use of finishes covers the methods and processes used to enhance the appearance or improve the function of materials including paper, board, polymers,
Topic Synopsis
The use of finishes covers the methods and processes used to enhance the appearance or improve the function of materials including paper, board, polymers, metals, and woods.
Key Concepts & Core Principles
- Protective finishes: Prevent corrosion (e.g., paint on steel), UV damage (e.g., varnish on wood), or moisture absorption (e.g., sealant on MDF).
- Aesthetic finishes: Enhance visual appeal through colour, texture, or gloss level (e.g., lacquer on brass, stain on oak).
- Functional finishes: Improve performance such as non-stick coatings (e.g., PTFE on pans), anti-slip surfaces (e.g., rubberised paint), or electrical insulation (e.g., enamel on copper wire).
- Application methods: Brushing, spraying, dipping, powder coating, electroplating, and anodising—each suited to different materials and production scales.
- Preparation and curing: Surface preparation (sanding, degreasing) and correct curing conditions (temperature, time) are critical for finish adhesion and durability.
Exam Tips & Revision Strategies
- Ensure products are designed to take account of potential corrosion due to environmental factors.
- Consider the suitability of specific finishes for different scales of production.
Examiner Marking Points
- Understanding of paper and board finishes: laminating, embossing, debossing, varnishing (UV/spot), and foil blocking.
- Knowledge of paper and board printing processes: screen printing, flexographic, offset lithographic, and digital printing.
- Awareness of polymer finishes: acrylic spray paints, thermoplastic elastomer, and the use of pigments in moulding (e.g., gel coats, smart pigments).
- Recognition of self-finishing polymers.
- Knowledge of metal finishes: cellulose paint, acrylic paint, electro-plating, dip coating, powder coating, galvanising, sealants, preservatives, anodising, plating, and cathodic protection.
- Knowledge of wood finishes: polyurethane varnish, acrylic varnish, water-based paints, stains, colour wash, wax finishes, Danish oil, teak oil, and pressure treating with chemical preservatives.