233.4 x 220mm double-sided copper-clad fibreglass PCB laminate photo-etch board coated with a high resolution photo-resist. Microtrak laminates consist of FR4 epoxy-glass laminate sheets, dip-coated with a positive working photo-resist. The photo-resist contains a dye that provides a good contrast against the copper and allows boards to be easily inspected at the developing stage. Boards are protected by a specially designed light-proof blue film which allows them to be guillotined without the risk of fracturing the photo-resist. * 233.4 x 220mm double-sided FR4 fibreglass laminate * Thickness 1.5mm * Copper thickness 35 micron * High resolution positive photo-resist * Supplied covered with blue light-proof film Microtrack FR4 boards require a developer strength of 10 to 1. (Not 20 to 1 as with other products it replaces.) Exposure time is typically 2.5 to 3.5 minutes. Click here for processing instructions. https://elecena.pl/product/27212351/fortex-microtrak-positive-photoresist-fr4-double-sided-233-4-x-220mm-1-sheet 2024-11-10 https://elecena.pl/product/27212351/fortex-microtrak-positive-photoresist-fr4-double-sided-233-4-x-220mm-1-sheet 2024-12-19 https://elecena.pl/product/27212351/fortex-microtrak-positive-photoresist-fr4-double-sided-233-4-x-220mm-1-sheet 2025-01-05 https://elecena.pl/product/27212351/fortex-microtrak-positive-photoresist-fr4-double-sided-233-4-x-220mm-1-sheet 2025-05-20 https://elecena.pl/product/27212351/fortex-microtrak-positive-photoresist-fr4-double-sided-233-4-x-220mm-1-sheet 2026-05-05 https://elecena.pl/product/27212351/fortex-microtrak-positive-photoresist-fr4-double-sided-233-4-x-220mm-1-sheet 2026-07-12