Preservation of Unearthed Metal Artifacts

The RP-A type agents with MGC exclusive film "Escal” film bags or containers creat oxygen and moisture free environments ideally suited for the preservation of unearthed metal artifacts.


Do not use Silica Gel with RP Agent Type A, Oxygen Absorbing Desiccant.
Because Silica Gel releases moisture and it degreases moisture absorption ability of RP Agent Type A.
We recommend combination of RP-K, Moisture independent Oxygen Absorber, and humidity control silica gel.
Please do not confuse usage of Type A with Type K.

The merits of using RP System

  1. Works on a simple principle. The system does not add anything to the artifacts.
  2. Simple to use. The preservation process starts immediately after the artifacts are put into a bag.
  3. It will keep for ±5 years after being packaged. Unnecessary to replace agents as with ordinary desiccants.
  4. Can be used as artifacts are excavated to keep them in order.
  5. Cost effective (per year cost) due to long term storage capability.
  6. Available in small quantities in some areas. Please inquire.

Precautions & Suggestions

Use of tray and cushions

Figure: Use of tray and cushions
A RP Agent
B Oxygen Indicator
C Humidity Indicator (Card)
D Air cap
E Resin Tray
F Cultural object

Choose trays & cushions which do not hold any moisture, such as plastic trays instead of cardboard trays or plastic bubble cushions instead of paper or cloth cushions.

Assorted packages

Figure: Assorted packages
A RP Agent
B Oxygen Indicator
C Polyethylene bag
D Cultural object

Put small artifacts in individual polyethylene bags and pack them in one Escal bag with RP agent.

Preserving Long Object

Photo: Preserving Long Object, like a sword

When Escal tube is used, any long object, like a sword, can be easily accommodated. Avoid using a bamboo tray which contains too much water.

Inquiries Concerning Products

Mitsubishi Gas Chemical Trading, Inc.
Specialty Materials Group
Specialty Materials Div.
Chemicals BU