Printing Aluminum, ps aluminum sheet

04/30 2026

Printing aluminum-commonly supplied as PS aluminum sheet (pre-sensitized aluminum)-is a purpose-built substrate for offset lithographic printing plates. It combines a carefully controlled aluminum alloy, precision rolling, electrochemical graining, anodizing, and a light-sensitive coating to produce a plate that images cleanly, runs stably on press, and delivers consistent dot reproduction over long print runs. For printers, plate makers, and trade shops, PS aluminum sheet is valued for its balance of image fidelity, durability, press stability, and process reliability.

What Is PS Aluminum Sheet?

PS stands for pre-sensitized: the aluminum base is treated and coated at the factory with a photosensitive layer (positive or negative working, depending on the process). The aluminum substrate is not "plain metal"-it is an engineered surface with:

Electrochemical graining to form micro-pits that hold fountain solution and improve coating anchorage
Anodizing to build a hard, porous oxide layer that increases wear resistance and hydrophilicity
Sealing (optional, process-dependent) to tune water retention and plate longevity
Photosensitive coating optimized for exposure, development latitude, and press performance

This manufacturing route creates the classic lithographic balance: non-image areas remain water-loving, while image areas accept ink after exposure and processing.

Features Customers Notice on Press

Feature	What it means in production	Customer benefit
High surface hydrophilicity	Non-image area holds water uniformly	Stable ink-water balance, reduced scumming
Tight thickness & flatness control	Plate clamps evenly and runs true	Faster make-ready, less vibration and waste
Robust anodic layer	Higher abrasion resistance	Longer run length, fewer plate changes
Uniform graining	Consistent micro-texture across the sheet	Smooth tone transitions, cleaner dots
Strong coating adhesion	Coating bonds to oxide pores	Reduced coating lift, improved durability
Good dimensional stability	Low residual stress after rolling and treatment	Less misregister, better repeat accuracy
Clean surface quality	Low inclusions, low contamination	Fewer pinholes, cleaner imaging

Typical Applications

PS aluminum sheet is widely used wherever offset lithography demands repeatable quality.

Application	Typical requirements	PS sheet advantages
Commercial offset printing	Crisp text, stable solids, midtone control	Consistent dot gain behavior and water balance
Packaging & labels	Long runs, abrasion resistance	Strong anodizing and coating durability
Book & publication printing	High speed, consistent registration	Flatness and dimensional stability
Newspaper & short-run jobs	Fast imaging and processing latitude	Reliable development and quick on-press start
General plate making (trade shops)	Multiple brands/workflows	Standardized specs, wide compatibility

Alloy and Temper Options (Common Industry Choices)

Most PS aluminum sheet for conventional plates uses AA1050/1060/1070 or similar high-purity aluminum for superior electrochemical graining response and hydrophilicity. Some suppliers also offer 3xxx-series options for specific mechanical needs.

Alloy (typical)	Purity / type	Typical temper	Why it's used
1050	≥99.5% Al	H18 / H19 (work hardened)	Balanced strength, excellent graining/anodizing response
1060	≥99.6% Al	H18 / H19	Higher purity, stable hydrophilicity
1070	≥99.7% Al	H18 / H19	High purity for consistent surface treatment
3003 (select cases)	Al-Mn alloy	H18	Added strength; may affect graining response

Note: Final plate behavior depends not only on alloy, but also on rolling history, surface treatment parameters, and coating system.

Chemical Composition (Typical Reference Ranges)

Below is a practical reference for common base alloys used in PS aluminum sheet. Actual limits should follow the supplier's mill test certificate and the relevant standard.

Element (wt.%)	AA1050 (typ.)	AA1060 (typ.)	AA1070 (typ.)
Al (min)	99.50	99.60	99.70
Si	≤0.25	≤0.25	≤0.20
Fe	≤0.40	≤0.35	≤0.25
Cu	≤0.05	≤0.05	≤0.04
Mn	≤0.05	≤0.03	≤0.03
Mg	≤0.05	≤0.03	≤0.03
Zn	≤0.07	≤0.05	≤0.04
Ti	≤0.05	≤0.03	≤0.03

Technical Specifications (Typical Supply Range)

PS aluminum sheet is specified by thickness, width/length, surface treatment grade, and coating system. The table below summarizes common supply ranges used by plate manufacturers and distributors.

Item	Typical range / option	Notes
Thickness	0.15–0.40 mm (common: 0.24–0.30 mm)	Chosen by press size, stiffness needs
Width	300–1350 mm	Coil or sheet formats
Length	400–2000 mm	Cut-to-size available
Temper	H18 / H19	Ensures stiffness and handling strength
Surface	Electrochemical grained + anodized	to lithographic performance
Anodic layer weight	1.0–3.0 g/m² (typ.)	Higher often improves run length
Surface roughness (Ra)	0.30–0.80 μm (typ.)	Tuned for coating and water retention
Coating type	Positive / negative PS	Matched to exposure workflow
Packaging	Anti-moisture + anti-scratch	Protects coating and oxide layer

Performance Parameters (What Buyers Should Ask For)

Because printing performance is a system outcome, the most useful "numbers" are the ones that correlate with imaging and press behavior.

Parameter	Typical expectation	Why it matters
Thickness tolerance	Tight, consistent across sheet	Registration stability and clamp fit
Flatness	Low wave / low camber	Reduces press vibration and waste
Surface uniformity	Even graining, no streaks	Prevents tone mottle and uneven wetting
Coating adhesion	High, no peeling during processing	Plate durability and reduced rejects
Anodizing quality	Dense, uniform oxide	Wear resistance and hydrophilicity
Defect control	Minimal pinholes, pits, scratches	Cleaner imaging and fewer press stops

Manufacturing Snapshot (Why the Surface Matters)

PS aluminum sheet is often described as "an aluminum plate," but performance is mainly driven by the engineered surface:

Process stage	Purpose	Result on plate
Precision rolling & stress control	Flatness, strength, dimensional stability	Better registration and handling
Degreasing & cleaning	Remove oils/contamination	Uniform graining and coating
Electrochemical graining	Create micro-pit texture	Water retention, coating anchor
Anodizing	Build porous Al₂O₃ layer	Wear resistance, hydrophilicity
Coating & curing	Apply photosensitive layer	Imaging performance and sensitivity
Slitting / sheeting / packaging	Prevent damage	Lower defect rate at customer site

How to Choose the Right PS Aluminum Sheet Quickly

Your priority	Recommended focus	Practical tip
Long run length	Higher-quality anodizing, robust oxide layer	Ask for anodic layer weight and run-length target
Sharp dots & smooth gradients	Uniform graining, controlled Ra	Request Ra range and surface uniformity control
Fast make-ready	Flatness and tight thickness control	Confirm flatness criteria and tolerance
Fewer defects	Cleanliness + packaging + inspection level	Specify defect acceptance and protective packaging
Workflow compatibility	Correct coating type and sensitivity	Match to exposure unit and developer chemistry

Storage and Handling Notes (To Protect the Coating)

Factor	Recommended practice	Risk if ignored
Temperature & humidity	Cool, dry storage; avoid condensation	Coating fog, oxidation, poor imaging
Light exposure	Store in original packaging	Unwanted pre-exposure
Handling	Use gloves; avoid abrasion	Scratches, fingerprints, coating damage
Shelf life	Use FIFO inventory	Sensitivity drift over time