How Is Rust Board (Medium Plaid) Manufactured? COLORIA's MCM Production Process

Every great material starts with great ingredients, and Rust Board (Medium Plaid) is no exception. The process begins with selecting a base metal alloy—typically a blend of iron and trace elements like copper and nickel. Why these? Iron provides the perfect canvas for the iconic rust finish, while copper and nickel slow down corrosion just enough to control the "age" of the patina. This alloy isn't pulled from a shelf; COLORIA's team works with suppliers who share their commitment to consistency, testing each batch for purity and structural integrity. After all, a weak base would mean a finish that fades or flakes, and that's non-negotiable.

But metal alone isn't enough. To achieve the "flexible" nature that makes MCM (Modified Composite Material) so revolutionary, we layer in a reinforced polymer core. Think of it as the backbone: lightweight but strong, allowing the final board to be installed on curved surfaces or high-rise exteriors without cracking. This core is sourced from recycled plastics where possible, a nod to COLORIA's sustainability mission—because beauty shouldn't come at the planet's expense.

With materials in hand, the next step is creating the base layer. The metal alloy is melted down and rolled into thin sheets, each about 0.8mm thick—thick enough to hold texture, thin enough to stay lightweight. These sheets are then cleaned with a mild acidic solution to remove any oxides or impurities; imagine prepping a canvas by wiping away dust before painting. Any leftover residue here would create uneven rust later, so precision matters.

Once clean, the metal sheets are bonded to the polymer core using a heat-activated adhesive. This isn't your average glue; it's a proprietary formula developed by COLORIA's engineers to ensure the two layers become one. The bond is tested under extreme temperatures—from -20°C to 60°C—to mimic real-world conditions. If a sample delaminates in testing, the adhesive blend is adjusted. No shortcuts here: a strong bond means a board that lasts decades, not years.

Now, enter MCM flexible stone—the secret sauce that sets COLORIA apart. Unlike traditional stone cladding, which is heavy and brittle, MCM flexible stone is a thin layer of natural stone particles (think marble dust, quartz, or in this case, iron oxide) mixed with a polymer resin. For Rust Board, we use iron oxide particles to enhance the rust effect later, ensuring the color runs deep, not just on the surface.

This stone-resin mix is applied to the metal-polymer base using a precision spray system. The layer is thin—only 2-3mm—but packed with stone particles for texture and durability. Why spray instead of roll? Spraying allows for a more even distribution, ensuring no area is too thick or too thin. It's like frosting a cake with a steady hand: too much, and it clumps; too little, and the base shows through. The goal is a consistent, breathable layer that lets the metal underneath "breathe" and rust naturally later.

Now, the "plaid" part. The "medium" in Rust Board (Medium Plaid) refers to the size of the pattern—neither too bold (large plaid) nor too subtle (small plaid). It's a balance that works in both cozy interiors and grand exteriors. To achieve this, the board is passed through a custom-texturing machine fitted with steel rollers etched with the plaid design. These rollers press into the stone-resin layer with controlled pressure—firm enough to leave a deep impression, gentle enough not to crack the material.

The pattern itself is a classic crisscross, with vertical and horizontal lines spaced 3cm apart. Why 3cm? Through client feedback and design studies, COLORIA found this size strikes the perfect visual balance: it adds interest without overwhelming a space. The rollers are cleaned after every 50 boards to prevent debris from smudging the pattern—because even a tiny nick in the roller would repeat across an entire batch, and that's not acceptable. After texturing, each board is inspected under light to check for consistent depth; any with uneven lines are set aside for rework.

Here's where the magic happens: turning the metal base into a rich, rusted finish. The textured boards are placed in a climate-controlled chamber where humidity, temperature, and oxygen levels are precisely regulated. A mist of saltwater and acetic acid is introduced—mimicking the natural aging process, but accelerated and controlled. Without this step, the metal would rust randomly, leading to splotchy, uneven color. With it, we get that warm, orange-brown patina that feels both timeless and intentional.

The chamber stays at 25°C with 85% humidity for 48 hours. During this time, the iron in the base reacts with oxygen and moisture, forming iron oxide (rust). The copper and nickel in the alloy? They create subtle variations in the patina—darker spots here, lighter streaks there—so no two boards look identical. It's like a fingerprint: each has its own character. After 48 hours, the boards are removed and rinsed with deionized water to stop the reaction, locking in the rust at its peak beauty.

Rinsed and rusted, the boards now need to cure. They're placed in a drying oven at 60°C for 72 hours, a slow process that allows the polymer layers to fully set and the rust to stabilize. Rushing this step is tempting—after all, clients are waiting—but heat too quickly, and the metal could warp; too slowly, and mold might form. 72 hours is the sweet spot, tested over years of trial and error.

While curing, the boards undergo a second round of bonding: the rust layer and stone-resin layer fuse with the polymer core, creating a single, unified material. Engineers check samples halfway through curing to measure hardness using a Shore durometer—a tool that presses into the surface to test resistance. A reading below 80 Shore D means the material is too soft; above 90, and it's too brittle. COLORIA targets 85-88, ensuring the board is tough enough for high-traffic areas but still flexible for installation.

Quality control isn't a final step at COLORIA—it's woven into every step. But after curing, each board undergoes a battery of tests. First, the "scratch test": a metal tool is dragged across the surface with 5N of force. No visible scratch? Pass. Next, the "impact test": a 500g weight is dropped from 1m onto the board. No cracks or dents? Pass. Then, the "weather test": samples are exposed to UV light and simulated rain for 1000 hours to check for fading or peeling. Only 2% color change is allowed—anything more, and the batch is re-evaluated.

Visual inspection is just as rigorous. Technicians check for consistent plaid spacing, even rust distribution, and no air bubbles in the resin. A board with a single off-center line or a patchy rust spot is rejected. It's strict, but that's why architects and designers trust COLORIA: they know what arrives on site is exactly what was promised.

Once approved, the boards are cut to standard sizes (1220x2440mm is most common) or custom dimensions per client requests. Edges are sanded smooth to prevent splinters during installation, and a clear, water-based sealant is applied to protect the rust finish from excessive moisture. This sealant isn't glossy—it's matte, preserving the raw, industrial look that makes Rust Board so appealing.

Finally, the boards are packed in recycled cardboard with foam inserts to prevent scratching during shipping. COLORIA even includes installation guides tailored to Rust Board, with tips like using stainless steel screws to avoid reacting with the rust finish. It's the little things that turn a material into a seamless experience.

Rust Board (Medium Plaid) is just one star in COLORIA's MCM galaxy. How does it stack up against other favorites like MCM flexible stone or foamed aluminium alloy board? Let's break it down:

So, where do you actually see Rust Board (Medium Plaid) in action? It's a favorite for restaurant backsplashes, adding warmth to otherwise sterile kitchen areas. Designers love it in home offices, pairing it with wood and leather for a balanced, masculine vibe. Exterior-wise, it's used on boutique storefronts, where the rust patina contrasts beautifully with greenery. One memorable project? A boutique hotel in Lisbon used it to clad an entire staircase, the plaid pattern guiding guests up with subtle visual rhythm.

What makes it so versatile? Its neutral color palette—warm oranges, deep browns, and hints of red—plays well with almost any decor. And because it's flexible, it can be bent to follow curved walls or archways, opening up design possibilities traditional stone can't match.

At COLORIA, sustainability isn't a buzzword—it's a practice. The polymer core uses 30% recycled plastic, reducing reliance on virgin materials. The metal alloy is sourced from suppliers who use 100% renewable energy in smelting. Even the rusting process is water-efficient, with the acid mist recycled and filtered before release. Waste is minimal too: offcuts from cutting are ground down and reused in the stone-resin layer, closing the loop.

The result? A material with a carbon footprint 40% lower than traditional rusted steel panels. For clients aiming for LEED or BREEAM certifications, Rust Board (Medium Plaid) is a smart choice—beauty with a conscience.