Plastics Engineering Glossary

Definitions of the materials, processes and test methods used in plastics laser marking and welding, surface pretreatment, adhesion bonding, coatings and product security, written for engineers who need to specify, qualify or troubleshoot them.

• Ablation
  What laser ablation is, how photothermal and photochemical removal differ, why it has a threshold, and when to choose it over marking or engraving on plastics.
• Accelerated Aging
  How accelerated aging predicts plastic part service life, the Arrhenius basis of ASTM F1980, and how to design a protocol that stands up to audit.
• Acrylonitrile Butadiene Styrene (ABS)
  ABS combines acrylonitrile chemical resistance, butadiene toughness and styrene rigidity. Properties, applications, and why ABS laser marks so readily.
• ASTM D3359 Tape Test
  ASTM D3359 tape test explained: X-cut and cross-hatch methods, the 5B to 0B scale, tape timing, and why 3M 610, 600 and 810 tapes give different results.
• Atmospheric Plasma
  Atmospheric plasma treats surfaces at ambient pressure without vacuum chambers. System types, cleaning and activation uses, and process control factors.
• Beam Steered Lasers
  Beam steered lasers use galvanometer mirrors to direct the beam at high speed. How steering works, technical limits, and why it suits marking and engraving.
• Carbonisation
  Carbonisation is the thermal decomposition that creates dark laser marks on plastics. How the charring mechanism works and what controls mark darkness.
• Cellulosics
  Cellulosic plastics are derived from renewable cellulose. Types, properties, applications, and how they behave in secondary decorating operations.
• Cold Gas Plasma
  Cold gas plasma activates and cleans surfaces without heat. How non-thermal plasma works, generation methods, applications and the limits to be aware of.
• Cold Laser Marking
  Cold laser marking uses femtosecond and picosecond pulses to mark without heat. How cold ablation works, compatible materials and where it is essential.
• Contact Angle
  How contact angle measurement quantifies surface wettability on plastics, what the numbers mean, sessile drop method, and how it differs from dyne pen testing.
• Digital Product Passport (DPP)
  What the EU Digital Product Passport requires, which products are affected first, and what carrying a DPP data carrier means for plastic parts.
• Dual-Purpose Laser Additives
  Dual-purpose laser additives enable marking plus a second function in one compound. Characteristics, benefits and applications across regulated industries.
• Electrical Air Plasma
  Air plasma uses ambient air energised by high-voltage discharge to clean and activate surfaces. System types, applications and treatment decay considerations.
• Electrical Corona Discharge
  Corona discharge surface treatment for plastics: how the high-voltage plasma works, typical 10-30 kV parameters, and where it improves ink adhesion.
• Environmental Stress Cracking
  Why environmental stress cracking causes most plastic part failures, how stress and chemical exposure combine, and how to prevent and test for it.
• Fibre Lasers
  Fibre lasers use a rare-earth-doped optical fibre as the gain medium. How they work, beam quality and efficiency advantages, types and selection factors.
• Flame Plasma
  Flame treatment activates hard-to-bond plastics in fractions of a second. How it works, where it beats corona and atmospheric plasma, and its limitations.
• Foaming (Laser Marking)
  How foaming produces light-coloured laser marks on dark plastics, why short pulses are required, and how foamed marks differ from carbonised ones in durability.
• Laser Colour Matching
  Laser colour matching creates consistent colours and contrast without inks. How thermal change and foaming produce colour, applications and the challenges.
• Laser Engraving
  Laser engraving ablates material to create deep permanent marks. Principles, laser wavelength selection, polymer engraving and parameter optimisation.
• Laser Etching
  Laser etching creates shallow marks a few microns deep by controlled melting. How it differs from engraving and marking, laser types, and key parameters.
• Laser irradiance
  Laser irradiance is power per unit area in W/cm2. How spot size, beam quality and power determine it, and why it governs plastics marking outcomes.
• Laser Marking Additives
  Laser marking additives make polymers markable: carbon-based, metal oxide, foaming and thermochromic types, how each works, and loading considerations.
• Laser Marking Nylon and Its Applications
  Laser marking nylon and polyamide: why the material resists marking, which additives create contrast, and the applications driving demand.
• Laser Plastic Welding
  Laser plastic welding joins thermoplastics without contact or consumables. How through-transmission welding works, joint requirements and applications.
• Laser Safety Officer (LSO)
  What a Laser Safety Officer does: responsibilities under ANSI Z136, OSHA and IEC 60825, hazard evaluation, training duties and required qualifications.
• Laser-Markable Plastics
  Which plastics accept laser marking and why: material types from PC and ABS to nylon and PP, mark durability, and the role of laser-sensitive additives.
• Liquid Crystal Polymer
  LCP offers exceptional dimensional stability, chemical resistance and high-temperature performance. Properties, applications and processing considerations.
• MOPA Laser
  MOPA lasers separate pulse generation from amplification, giving adjustable pulse width from 2 to 500 ns for damage-free marking of dark and light plastics.
• Pad Printing
  How pad printing transfers images onto contoured plastic parts, why surface pretreatment is critical, and how to diagnose common print defects.
• Polycarbonate
  Polycarbonate combines optical clarity with high impact strength. Properties, laser cutting, engraving and welding considerations, and processing challenges.
• Polyester
  Polyester thermoplastics including PET and PBT. Properties, semi-crystalline behaviour, applications, and implications for bonding and laser marking.
• Polyetheretherketone (PEEK)
  PEEK properties, why it is specified over PPS and PEI, how it responds to laser marking, and what makes bonding and printing on PEEK difficult.
• Polyethylene
  Polyethylene classified by density and branching: LDPE, HDPE and cross-linked. Properties, applications, and why PE is difficult to decorate and mark.
• Polyphenylene Sulfide
  PPS delivers 240C service temperature, inherent UL 94 V-0 flame retardancy and broad chemical resistance. Properties, grades, applications and safety.
• Polypropylene
  Polypropylene is tough, rigid, chemically inert and fully recyclable. Properties, chain structures, applications and why PP resists bonding and marking.
• Polyurethane
  Polyurethane spans flexible foams to rigid elastomers. Properties, processing routes, and what PU means for bonding, coating and laser marking.
• Pyrosil Flame Plasma
  Pyrosil deposits a nano-thin silicon dioxide layer via silane-doped flame to boost adhesion on plastics, glass and metal before printing, coating or bonding.
• Surface Energy
  What surface energy means for plastics, why polyolefins resist bonding, typical dyne levels by polymer, and how to raise and verify it before bonding.
• Thermoplastic Elastomers
  Thermoplastic elastomers combine rubber elasticity with thermoplastic processing. Properties, applications, and what TPEs mean for bonding and marking.
• Through-Transmission Laser Welding
  How through-transmission laser welding joins plastics, why one part must transmit and the other absorb, joint design requirements, and common weld defects.
• Unique Device Identification (UDI)
  What UDI requires of medical device marking, the difference between DI and PI, direct part marking rules, and how laser marking meets permanence requirements.
• Vanadate Laser
  Nd:YVO4 vanadate lasers offer high beam quality in compact form at 1064 nm. Key features, plastics and micromachining applications, and Nd:YAG comparison.
• Ytterbium Fibre Laser
  Ytterbium fibre lasers operate at 1030-1100 nm with over 30% efficiency. Key features, plastics marking applications and advantages over CO2 and Nd:YAG.

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