EPP Europe P2.2023

» PCB & ASSEMBLY
Questionable reliability
The adhesives used in manual stick-on labels can
fail over time if exposed to humidity, high temperatures,
abrasion, or chemicals. Labels can peel, fall off,
become illegible or disappear completely – resulting
in products with missing or incorrect identification
markers. This makes ongoing traceability and warranty
tracking difficult.
Restricted options
Manual labels can only be applied on accessible
surfaces with enough area for adhesion. Irregular
shapes, smaller sizes, and hidden areas restrict where
labels can be placed. Only certain materials can be
labelled, and these must meet size requirements for
human handling. All these constraints limit options
for product design and labelling location.
Additionally, manual labelling cannot fulfil the obligations
for permanent marks mandated by certain
regulatory requirements like unique device identification
(UDI). Overall, the limitations and disadvantages
inherent to manual labelling make it unsustainable
for high-quality electronics production.
Is laser labelling the answer?
Automated and precise, modern laser marking systems
bypass the limitations of manual labelling by
offering permanent marking capabilities. Although
manufacturers may be put off by the initial outlay to
purchase the equipment, laser marking has numerous
advantages that far outweigh the investment
cost. Such systems have become integral to production
lines, prompting many CEMs to opt for laser
marking technology.
Range of labels with a range of sizes and information attributed
Source: Altus
Permanent marks
Lasers create marks by altering the surface structure
of materials through ablation, oxidation, melting
or other photochemical processes. This means labels
become integral, permanent parts of the product
and are not just stuck on. Laser marked identification
withstands wear, abrasion, temperature extremes
and chemical exposure. Electronics OEMs can trace
labelled products across their entire lifecycle.
Precision and legibility
Lasers can etch intricate details and small font
sizes down to micron levels. Complex machine-readable
codes like barcodes can be inscribed with perfect
precision and accuracy. This prevents errors in
component identification – especially critical for
complex miniature electronics parts. Laser labelling
is effective on unusual shapes and designs, including
on curved, angled or hidden surfaces not reachable
using manual methods.
Hands-free
Laser marking is a non-contact process. It does not
require physical contact with the PCB surface, unlike
ink printing or mechanical engraving methods. The
laser imprints by directing focused light energy onto
a material to alter its structure without touching it.
This non-contact process eliminates any risk of damage,
distortion, or stress to delicate electronic
components during marking. This enables safe, clean,
and damage-free identification of even the most
sensitive, densely-packed PCB designs. It can also be
applied on various surfaces, from metals and ceramics
to laminates and plastics, making it ideal for
modern high-mix electronic components.
28 EPP Europe » 11 | 2023