In ceramic production, a common phenomenon arises: with the same formulation and the same forming process, some products absolutely require binders — without them, they simply cannot be made; while other products can be produced normally without any binder.

Why?

2.1 Only "Weak Bonds" Between Particles

Before firing, ceramic bodies have no true chemical bonds between particles. What holds them in shape?

• Capillary force: Negative pressure from water menisci between particles "pulls" them together
• Van der Waals force: Weak physical attraction between particles
• Limited bonding: Colloidal properties of clay minerals themselves

2.2 Different Forming Methods, Different "Fragility Levels"

3.1 Thin-Walled Products — Inherently Insufficient Strength

Typical products: Thin-bodied porcelain, high-end tableware, thin tiles, art porcelain.

The thinner the wall, the lower the flexural strength. A bowl body with 3mm wall thickness may have only one-third the flexural strength of an 8mm body. During demolding, trimming, and handling, even slight external force can cause edge chipping, corner damage, and cracking.

3.2 Large-Format Products — Self-Weight Is the Threat

Typical products: Large-format tiles (e.g., 900×1800mm), large sanitary ware (toilets, bathtubs), large art pieces.

The problem with large-format bodies is not thin walls but excessive self-weight. A toilet body can weigh 20–30 kg. During demolding, flipping, and handling, the torque and stress the body bears far exceed those of smaller products.

3.3 Complex Shapes — Stress Concentration

Typical products: Complex sanitary ware, carved tableware, complex-shaped art porcelain.

Complex shapes mean uneven wall thickness. Thick and thin sections shrink at different rates during drying, creating stress concentration at the transitions — highly prone to cracking.

3.4 High Lean-Material Formulations — Lacking "Natural Binder"

Typical products: High-whiteness tableware, premium sanitary ware, high-end tiles.

In traditional ceramic formulations, clay (especially ball clay and bentonite) serves as a natural "binder," providing plasticity and green strength. But modern high-end ceramics, in pursuit of high whiteness and high translucency, often:

• Reduce clay content
• Increase the proportion of lean materials such as quartz and feldspar
• Use refined clays that have been washed and de-ironed

3.5 Fast Drying Processes — Not Enough Time

Modern ceramic production pursues efficiency, with drying cycles getting shorter and shorter. But fast drying means:

• Rapid moisture evaporation and high shrinkage stress
• Not enough time for the body to release stress through creep
• Significantly increased cracking risk

The binder's core task is to build a temporary "skeleton" between particles.