The core advantages of double wall glasses lie in heat insulation, scald prevention, cold retention, and freshness preservation. However, their double-layer hollow structure and glass material also make them relatively delicate. To extend their service life, it is necessary to avoid damage risks from three dimensions: daily use, cleaning and maintenance, and storage.

I. Daily Use: Avoid Temperature Shocks and Physical Damage

1. Strictly prohibit sudden temperature changes to prevent cup cracking.

The temperature difference tolerance between the inner and outer walls of double wall glasses is limited, which is the primary cause of cracking. When pouring hot water, first pour a small amount of warm water to preheat the cup, shake it evenly, and then add boiling water. Similarly, do not put ice cubes directly into the cup before filling it with iced drinks; instead, add a small amount of cold water for transition. Never place a cup that has just contained boiling water into the refrigerator immediately, or pour boiling water into a cup that has just been taken out of the refrigerator. It is recommended to control the temperature difference within 50℃.

2. Handle with care to avoid collision and extrusion.

The walls of double wall glasses are usually thinner than those of single-wall glasses, and the hollow structure has weak impact resistance. Handle the cups gently when picking and placing them; do not collide with hard objects such as metal tableware or stone countertops. Place them stably to avoid tipping over due to tilting. Pay special attention to the rim and bottom of the cup—these two parts are stress concentration areas, which are prone to hidden cracks after collision, and the damage will expand during subsequent use.

3. Control beverage types and keep away from corrosive liquids

Double wall glasses are not suitable for long-term storage of strong acid or alkaline beverages, such as concentrated vinegar, lemon juice, carbonated drinks, and traditional Chinese medicine decoctions. Such liquids may corrode the protective layer on the glass surface, causing the cup wall to lose its luster. Worse still, they may seep into the double-layer gaps, leading to bacterial growth that is difficult to clean. If such beverages are contained, the cup must be cleaned immediately after drinking.

II. Cleaning and Maintenance: Clean Gently to Avoid Material Damage

1. Choose the right cleaning tools to prevent scratches.

For cleaning, prioritize microfiber cloths, soft sponges, or special soft-bristle cup brushes. Never scrub with rough tools such as steel wool, hard-bristled brushes, or scouring pads; otherwise, scratches will be left on the glass surface, which not only affect the appearance but also reduce the compressive capacity of the glass. For hard-to-reach areas such as the rim, bottom, and double-layer joints, wipe with cotton swabs dipped in warm water.

2. Use mild detergents to reduce residual corrosion.

Warm water is sufficient for daily cleaning. For stubborn stains such as tea stains and coffee stains, choose fragrance-free neutral dish soap. Avoid using strong cleaners containing fragrances, bleaching agents, or abrasive particles. After cleaning, be sure to rinse off the foam thoroughly with running warm water to prevent residual detergent from corroding the glass.

3. Remove stubborn stains gently; avoid chemical solvents

For tea stains and limescale, prepare a vinegar-warm water solution to soak the cup for 10–15 minutes, or wipe with lemon slices to dissolve the stains with weak acid, then rinse with warm water. Do not use strong alkaline or oxidizing cleaners such as baking soda or toilet cleaners, and do not scrape stains with hard objects to avoid damaging the cup wall.

III. Storage: Keep Dry and Dust-Free to Avoid Secondary Damage

1. Store only after thorough drying to prevent mold growth.

After cleaning, place the double wall glass upside down on a draining rack and air-dry it in a well-ventilated area, ensuring no water remains inside the cup, especially in the gaps of the double-layer joints. Residual moisture will lead to mold growth during long-term storage and may cause aging and peeling of the adhesive layer at the joints. Never dry the cup with a cloth to avoid residual lint.

2. Store separately to avoid extrusion and friction.

For storage, it is recommended to place the double wall glass in a dedicated cup holder or wrap it with a soft cloth before putting it into a cabinet. Do not stack it with other tableware to prevent scratching or cracking of the cup body. Place the cup with the rim facing up to avoid dust and debris falling into the cup. If the cup is equipped with a lanyard or sleeve, remove and clean them regularly to prevent corrosion of the cup body by sweat and stains.

3. Check regularly and deal with hidden damage promptly.

Before each use, check if there are cracks, chips, or delamination of the double layers on the cup body. If fine cracks are found on the cup wall, even if they do not affect use temporarily, it is advisable to stop using it. Because the cracks will expand rapidly under temperature changes or external forces, leading to a cup explosion.