There are two distinct manufacturing methods: high-pressure and direct pressure lamination.
High-pressure lamination, the bottom and top layers are separately heated and pressurized into a laminate structure. These layers are then fused to the core under heat and pressure. This is a much more expensive process and adds strength to the overall product.
Direct-pressure lamination is where the layers are assembled all at once then filled with hardening melamine resins using heat and pressure. High-pressure lamination, the original method, is more impact- and dent-resistant while direct-pressure laminates are more economical and offer very good quality overall.