SPI-Chem Wet Surface Replica Kit Including Resin, Catalyst, Powder, and Instructions
The SPI Supplies Wet Surface Replication Kit consists of a proprietary silicone resin for forming the negative replicas, the catalyst to be mixed with the resin immediately before application, the droppers necessary to measure the catalyst, complete instructions and the polymer powder to convert the negative replicas into permanent, positive replicas which can be gold coated for analysis by light microscopy or SEM.
Replacement Components of Kit:
01090A-AB SPI-Chem™ Replacement Catalyst for use with SPI-Chem™ Wet Surface Replica Kit
01090B-AB SPI-Chem™ Silicone Replicating Resin for use with SPI-Chem™ Wet Surface Replica Kit, 1 Pint
01090C-AB SPI-Chem™ Replacement Powder for use with SPI-Chem™ Wet Surface Replica Kit
Replication allows the microscopist to conduct before/after studies and other challenging protocols on samples that cannot be put directly into the microscope, such as biological samples like living human skin (including oral tissue) and growing leaves, polished surfaces (like shoes and automobiles) and wear tracks. The SPI Chem Wet Surface Replication Kit is designed for the particular challenges of surfaces that cannot be made suitable for the SEM environment by critical point drying or other techniques. Example of successful studies using this system include :
- Before/after studies of human skin to show the effect of skin "moisturizers" or other cosmetic and toiletry products.
- Before/after shaving studies, allowing measurements to be made on individual, growing whiskers, as a function of time.
- In-the-mouth studies showing the removal of plaque, margin creep of dental restorative materials, gingival sulcus and the effects of oral hygiene products.
- Before/after studies of automobile waxes and shoe polishes.
- Growing plant surfaces like leaves and fruits.
- Industrial wear surfaces, including "hot" surfaces, as a function of time, such as grinding wheels, rollers, presses, stampers, tool and die surfaces, diamond cutting surfaces, etc.
In order to be successful in these challenging protocols, the replicating material must have all of the following characteristics:
- Cause no change to the surface being replicated and in the case of skin mucousal surfaces, product no irritation to the test subject.
- "Cure" within seconds to prevent artifacts from changes due to the occlusive covering (important for skin and mucousal studies).
- Be fluid (low enough viscosity) to conform completely with the subject surface but not completely "wet" the surface.
- Allow conversion to positive replicas.
- Be artifact-free up to at least 500X.
The process consists of preparing the area to be examined, mixing the resin and catalyst and immediately applying it to the surface of interest, building up additional resin layers to provide mechanical strength in the replica and stripping the replica. In the laboratory, the negative replica can be converted into a positive replica.
We do not recommend this system for metallurgical fractography, but it has been extremely useful for providing a record of the macroscopic fracture features of samples which could not be destroyed for testing. We do not recommend this system for magnifications above 700X. The silicone negative itself has a poor shelf life, but positive replicas have been successfully stored in our laboratories for over 30 years without any apparent change.
And last but not least, the learning curve needed to actually "make" good replicas is not long and involved and while the first replicas you make might not be absolutely "perfect", one does not have to practice years and years to make good replicas. Typically in one day, you are learning how to make good quality "negative" and also "positive" replicas. And this is made very easy by the easy-to-follow Instructions for Use that accompany each kit or which can be previewed on this website.
1. Garber, Charles A, "Characterizing Cosmetic Effects and Skin Morphology
by Scanning Electron Microscopy", J. Soc. Cosmet. Chemists, 27, 509-531 (November 1976).
2. Garber, Charles A, "Characterizing Cosmetic Effects and Skin Morphology
by Scanning Electron Microscopy", Presented at Society of Cosmetic Chemists
(SCC) Annual Educational Symposium, May 1975, St. Louis.
3. Garber, Charles A., "Characterizing 'moisturized skin' by Scanning
Electron Microscopy", Cosmetics and Toiletries, (April, 1978) 74
Contents of the SPI Wet Surface Replica Kit:
- 1 pint of resin for production of negative replicas
- 10ml of catalyst for production of negative replicas
- 500g of polymer powder for production of positive replicas
- 10 pipettes and 2 squeeze bulbs
- Complete instructions
Each kit contains the following:
Making the negative:
Specially purified silicone resin, 1 pint
Making the positive:
Replicating Powder 500gms
Resin and catalyst: Store under refrigeration
Positive replica powder: Room temperature
Non-hazardous from the stand point of shipping