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Customized sizes aluminum positive thermal ctp computer to plate


Customized sizes aluminum positive thermal CTP plates deliver precise dot reproduction, high press stability, and excellent run length for offset printing. Ideal for commercial, publication, and packaging printing, these plates offer consistent quality, fast imaging, and compatibility with leading thermal CTP systems.

Customized sizes aluminum positive thermal CTP (Computer-to-Plate) plates are specially designed printing plates for thermal laser imaging systems. They use a grained and anodized aluminum base with a positive-working thermal coating. After exposure, the imaged areas are removed in the developer, leaving a durable, ink‑receptive image for offset printing.

These plates are available in tailor‑made sizes, thicknesses, and packing configurations to fit different CTP setters and press formats, from small commercial sheet‑fed jobs to large-format newspaper and packaging presses.

Features

  • Compatible with 830 nm thermal CTP systems
  • Excellent dot reproduction from highlights to shadows
  • Controlled aluminum grain and anodizing for strong hydrophilicity
  • High press run length, both with and without baking (depending on conditions)
  • Wide processing latitude and stable performance in standard positive developers
  • Fast imaging sensitivity for higher CTP throughput
  • Customized sizes, gauge, and packing to match specific workflows
  • Low scumming and clean background for sharp prints

Typical Applications

  • Commercial offset printing
  • Magazine, catalog, and book printing
  • Newspaper and semi-commercial printing
  • Labels, flyers, brochures, and posters
  • Light packaging and folding carton work
  • General multi‑color sheet‑fed and web offset jobs

Aluminum Alloy & Temper

Most positive thermal CTP plates are produced from non‑heat treatable, high‑purity aluminum alloys optimized for graining and anodizing, such as 1050, 1060, or 3003.

ParameterTypical Value / OptionNotes
Alloy series1000, 3000High purity, excellent surface treatment properties
Common alloy grade1050, 1060, 3003Chosen according to required mechanical strength
TemperH18, H19, H16Work‑hardened for stiffness and dimensional stability
Thickness range0.15–0.40 mmOther gauges on request
Surface treatmentElectrochemical graining + anodizingProvides micro‑roughness and oxide protection

Typical Chemical Composition of Base Aluminum

Values below are representative for a 1050/1060‑type alloy used for CTP plates.

ElementTypical Content (%)Function / Effect
AlBalance (≥ 99.50)High purity base, good corrosion resistance
Si≤ 0.25Controls grain structure and mechanical properties
Fe≤ 0.40Strengthener; kept low for better surface quality
Cu≤ 0.05Excess can reduce corrosion resistance
Mn≤ 0.05Minor strengthening element
Mg≤ 0.05Usually very low for consistent anodizing
Zn≤ 0.05Limited to avoid galvanic issues
Ti≤ 0.03Grain refiner during casting
Others≤ 0.03 each / 0.10 totalImpurity limits for process stability

Exact composition may vary slightly with alloy grade and mill source but remains strictly controlled for plate consistency.

Technical Specifications

General Plate Parameters

ItemTypical Specification
Plate typePositive thermal CTP
Imaging wavelength830 nm (thermal laser)
Sensitivity range120–170 mJ/cm²
Plate thickness options0.15 / 0.20 / 0.25 / 0.30 / 0.40 mm
Maximum supplied widthUp to 1500 mm (customizable)
LengthsCut to order according to CTP and press
Surface roughness (Ra)0.30–0.60 μm (typical)
Anodizing layer weight2.5–3.0 g/m² (standard)
Base colorSilver metallic aluminum
Coating colorLight blue, dark blue, or customized

Imaging & Processing Performance

ParameterTypical Value / RangeNotes
Laser type830 nm thermal diodeCompatible with major CTP brands
Resolution capabilityUp to 2400–2800 dpiHigher dpi supported depending on CTP
Screen rulingUp to 200–250 lpiSuitable for high‑resolution work
FM screening≥ 20 μm stochastic dotsStable highlight dot reproduction
Dot reproduction range1–99% at 200 lpiUnder standard setup and processing
ProcessingPositive thermal developerSuitable for common automatic processors
Processing speed0.8–1.5 m/min (typical)Variable with chemistry and machine
Processing temperature23–28 °CStandard developer operation window
Safe‑light requirementsDaylight handleable before imagingNo darkroom needed
Preheat requirementNot required for standard runsBaking optional for long runs

Run Length & Durability

Run length depends on press conditions, ink type, fountain solution, paper, and maintenance practices.

ConditionTypical Run Length (Impressions)
Conventional ink, unbaked80,000–150,000
Conventional ink, baked200,000–300,000 or more
UV ink, unbaked30,000–60,000
UV ink, baked80,000–150,000
Alcohol‑reduced dampeningSlightly reduced vs. conventional setups

Values are indicative; final performance may vary with press environment and ink/fountain system.

Thermal Stability & Flatness

ParameterTypical Specification
Gauge tolerance± 0.005 mm
Width tolerance± 0.5 mm (tighter on request)
Length tolerance± 1.0 mm
Flatness≤ 1.0 mm bow per meter length
Coating weight1.0–1.8 g/m²

Tight control of temper and thickness ensures good vacuum contact on CTP devices and reliable register on press.

Customization Options

Customized sizes aluminum positive thermal CTP plates are designed to fit individual printing setups and logistics.

Customizable ItemDescription / Options
Plate dimensionsFully customized width and length to fit each CTP and press
Thickness selectionStandard gauges plus special requests for special presses
Edge finishingRounded or straight edges depending on clamping system
Corner treatmentSquare or chamfered corners
Packing formatBoxes, cartons, pallets; vertical or horizontal packing
Interleaving materialPaper or plastic interleaf; anti‑scratch protection
Branding / labelingCustomized box labels, barcodes, and internal IDs
Surface roughness targetSlight adjustments for specific ink/paper combinations

Storage & Handling Guidelines

Proper storage significantly extends plate shelf life and preserves performance.

ItemRecommendation
Storage temperature18–24 °C
Relative humidity40–60% RH
Shelf life (unexposed)12–18 months in original packaging
Light exposureKeep away from direct sunlight and UV sources
stackingStore flat or vertically with adequate support
HandlingHold by edges; avoid fingerprints and scratches

Advantages in Daily Production

  • Stable and predictable imaging across plates, days, and batches
  • Fewer remakes thanks to controlled chemistry interaction
  • Clean background and low tendency to scum or toning
  • Strong adhesion of coating to aluminum for reduced coating loss
  • Low chemical consumption due to robust coating design
  • Flexible customization for printers running multiple press formats

Compatibility

These positive thermal CTP plates are compatible with most 830 nm thermal CTP engines from leading manufacturers, including common drum and flatbed systems, as well as automatic plate loading and online punching units. They run well with standard positive developers and replenisher systems from major chemistry suppliers.

For each customer, test recommendations and setting guidelines can be provided to optimize laser power, drum speed, and processing parameters.

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