First distinguish between glass iridescent marks and material mould growth
White spots, fog or rainbow-like marks appear on glass after storage, which is often collectively referred to as “glass mould” in appearance. This type of surface change involves weathering and corrosion of glass under the action of moisture and is not judged in the same way as mould growth on textiles.
For iridescent marks on the edge of the glass, we check the surface marks, separators and packaging moisture, and select a moisture-proof treatment path based on the weathering, corrosion and storage status of the material.
Comparing two glass-packaging configurations in the same warehouse
In a group of glass packaging observations, we packed the same specifications of glass into two boxes: one box used ordinary corrugated boxes and glass spacers, and the other box added mineral desiccant based on the same packaging. The two boxes are placed in the same warehouse and are unpacked and observed monthly.
The comparison focuses on how the appearance of the glass edge changes after adding moisture-proof configuration.
Actual observations from the second to the sixth month
Records show that there were no obvious abnormalities in either group during the first month of unpacking. In the second month, small iridescent marks began to appear on the edge of the glass without desiccant; in the sixth month, the range of the group of iridescent marks expanded, and the glass with desiccant added remained intact during the current observation.
Two photos record the edge state of this group of glass under corresponding packaging and storage conditions, as an image record of this monthly observation.
Hygroscopic and moisture-blocking matching for glass packaging
In actual packaging, in addition to the air moisture during sealing, the moisture introduced by the spacer paper, cartons and wooden accessories should also be checked. Depending on the moisture resistance of the packaging, storage time and environmental changes, the desiccant load will also be different.
The hygroscopic material is arranged to cover the edge space of the glass and the air channel inside the package. We test-assemble according to the separator, lining and carton structure, matching specifications and positions.
Use fixed-point unpacking records to review the moisture-proof plan
During trial installation, the same glass, same separators and packaging can be retained, and only the moisture-proof configuration to be compared can be changed. Record the edge, contact surface and carton status every time you open the box, and use a consistent shooting position to easily track whether the marks are new or expanded.
Iridescent marks have been classified and processed according to surface damage and usage requirements; subsequent orders are equipped with drying, paper separation and moisture-proof packaging to reduce similar abnormalities.
Frequently asked questions
Are iridescent marks on glass necessarily caused by fungi?
White spots, iridescent marks, or hazy changes on glass can involve weathering and corrosion. We conduct cause analysis based on the location of the stains, moisture in the packaging, and material condition.
Can this set of six-month records be used as the protection period for all glass packaging?
Records reflect historical observations that this group of glass and packaging are in the same warehouse. For new orders, engineers will configure moisture-proof solutions based on glass, separators, packaging moisture-proofing, and storage and transportation cycles.
How to use cartons and separators to protect glass from moisture?
We design a moisture-proof solution for glass packaging by combining the carton and separator paper to carry water, allow external water vapour to enter, and encapsulate moisture-blocking and moisture-absorbing configurations.
Updated: 2026-10-29
