The heat insulation principle and design of anti-scalding tableware

The heat insulation principle and design of anti-scalding tableware

The core design of anti-scalding tableware lies in blocking or weakening the heat transfer path. Through structural innovation and material application, the heat insulation function is achieved. The following analysis is conducted from three dimensions: heat insulation principle, structural design, and material selection:

First, the principle of heat insulation

Physical thermal resistance effect

Air insulation layer: A hollow interlayer is set in the tableware wall (such as a double-layer bowl structure), taking advantage of the low thermal conductivity of air (thermal conductivity coefficient approximately 0.026W/(m·K)) to block heat transfer.

Liquid medium heat insulation: Fill the bottom or side walls of the bowl with liquid water or other heat insulation media. The high specific heat capacity of the liquid absorbs heat and reduces the temperature of the outer wall. Experimental data show that liquid filling can reduce the temperature of the outer wall by 45-60℃.

The heat conduction path is prolonged

Multi-layer composite structure: It adopts the superimposition of multiple layers of materials (such as ceramic outer layer + metal inner layer + insulation interlayer), and extends the heat conduction path through the difference in thermal conductivity of different materials (ceramic about 1.5W/(m·K), metal about 50W/(m·K)).

Wavy or raised structure: Wavy patterns or raised parts are designed on the surface of tableware to increase the contact area and path length for heat transfer and reduce the heat flux density per unit area.

Second, structural design

Double-layer or multi-layer structure

Inner and outer layer separation: The inner layer comes into contact with food, the outer layer provides insulation, and the middle is isolated by a vacuum or air layer. For example, the vacuum layer of a double-layered glass can reduce heat convection and conduction.

Detachable insulation layer: Some tableware is designed with replaceable silicone sleeves or insulation pads. If damaged, they can be directly replaced to extend the service life.

Bottom and edge optimization

Raise the bottom: Increase the height of the bowl bottom by 1-2cm to keep your fingers away from the heat source and increase the heat dissipation area at the bottom.

Anti-scald diagonal lines or raised grooves: On the bottom of the outer side of the bowl body, raised diagonal lines or finger-shaped grooves are designed, which not only form a physical insulation layer but also enhance the stability of holding (for example, the stability of end holding is increased by 70%).

Ergonomic fit

Double-ear or wide-edge design: By adding handles or wide edges, the direct contact area between fingers and heat sources is reduced. For example, the smooth handle of the double-eared soup bowl can disperse the pressure of holding.

Finger-shaped groove: A groove is set along the bottom edge of the bowl, which can accommodate more than two fingers, avoiding the risk of overflow caused by the traditional end-holding method.

Third, material selection

Materials with low thermal conductivity

Ceramics and glass: They have low thermal conductivity (about 1.5W/(m·K) for ceramics and about 1.0W/(m·K) for glass), and are heat-resistant, making them suitable for use as the main body of tableware.

Silicone and rubber: They have a lower thermal conductivity (about 0.2W/(m·K)) and are often used to make heat insulation covers or handles, providing a soft touch and anti-slip performance.

Application of Composite Materials

Metal + ceramic composite: The inner layer is metal (such as stainless steel) to facilitate uniform heat conduction, and the outer layer is ceramic to provide heat insulation and aesthetic appeal.

Polymer insulation materials: such as aerogel felt (with a thermal conductivity of approximately 0.013W/(m·K)) or nano-porous materials, can be embedded in the walls of tableware to achieve ultra-thin insulation.

Surface treatment technology

Hydrophobic and oleophobic coating: Reduces food residue and heat accumulation, and is also easy to clean.

Reflective coating: High-reflectivity materials (such as aluminum foil) are applied to the inner or outer walls of tableware to reflect thermal radiation and reduce the temperature of the outer wall.

Fourth, comprehensive design cases

Anti-scald bowl design

Structure: The bottom of the bowl is equipped with an insulating cavity filled with liquid water. The height of the cavity is 1/5 to 1/4 of the total height of the bowl. The outer bottom is designed with raised diagonal patterns and finger-shaped grooves.

Effect: When holding liquid at 100℃, the outer wall temperature can be maintained below 50℃, and the end-holding stability is improved by 70%.

Anti-scald paper cup design

Structure: It adopts a double-layer paper cup structure. Anti-scald blocks are set between the inner cup and the outer cup, and they are fixed by interlocking blocks and interlocking slots.

Effect: The heat insulation performance is enhanced, and the structure is stable, making it suitable for holding hot drinks.