SAFETY DATA SHEET

1
1. CHEMICAL AND COMPANY IDENTIFICATION
Product Identifier: HARDCAST A, SILMASTER A, SILPLASTIC A,
SILTOOL A, THERMOCAST II A

Use: Component for Polyurethane Casting Plastic;
Professional/Industrial use

Company: SILPAK, INC.
470 EAST BONITA AVE. POMONA, CA 91767
Phone Number: 909-625-0056
Emergency Phone: CHEMTREC 1-(800)-424-9300

Email: silpak@aol.com

2. HAZARDS IDENTIFICATION
GHS HAZARD CLASSIFICATION:
Acute Toxicity Inhalation Category 4
Skin Corrosion/ Irritation Category 2
Eye Damage/Irritation Category 2
Respiratory Sensitizaton Category 1
Specific Target Organ Toxicity Category 3
(Respiratory Tract Irritatant)

SIGNAL WORD: WARNING!

Contains Diphenylmethane Diisocyanate (MDI, isocyanate)

HAZARD STATEMENTS:
May be harmful if inhaled; May cause respiratory irritation; Causes mild
skin irritation; Causes serious eye irritation; May cause allergy or asthma
symptoms or breathing difficulties if inhaled; May cause an allergic skin
reaction; May cause damage to organs through prolonged or repeated
exposure.

PRECAUTIONARY STATEMENTS:
Do not handle until all safety precautions have been read and understood;
Avoid breathing fumes/mist/vapors/spray; Wash thoroughly after handling;
Wear protective gloves/ protective clothing/ eye protection/face protection;
In case of inadequate ventilation, wear respiratory protection; Take off
contaminated clothing and wash before reuse.

IF ON SKIN: Wash with plenty of soap and water.
IF IN EYES: Rinse cautiously with water for several minutes. Remove
contact lenses, if present and easy to do. Continue rinsing.
IF INHALED: If breathing is difficult, remove person to fresh air and keep
at rest in a position comfortable for breathing.

Store in a well ventilated place. Keep container tightly closed.
Dispose of contents and container in accordance with local, regional and
national regulations.

SUPPLEMENTAL INFORMATION
Primary Routes of Exposure: Inhalation, Skin, Ingestion, Eye.
Individuals sensitized to isocyanates should discontinue use. Long-term
overexposure to isocyanates may cause lung damage. This is one part of
a two-component system. Read and understand the hazard information
on part B before using.

3. COMPOSITION / INFORMATION ON INGREDIENTS

CHEMICAL CAS NO. WGT.%
4,4-Diphenylmethane Diisocyanate 101-68-8 25-60
Higher Oligomers of MDI 9016-87-9 30-50
Chlorinated Paraffin Hydrocarbon NE 5-40
*Ingredients not precisely identified are proprietary or not hazardous.
NE-Non Existent.

4. FIRST AID MEASURES
INHALATION: Remove person to fresh air. If not breathing, give mouth to
mouth resuscitation. If breathing is difficult, give oxygen. Consult a
physician immediately.
SKIN CONTACT: Remove contaminated clothing. Wash contact area
with warm water and soap. Wash contaminated clothing before reuse.
EYE CONTACT: Immediately flush eyes with plenty of water for 15
minutes, holding eye lids open to be sure the material is washed out.
Consult a physician immediately.
INGESTION: Do not induce vomiting. No adverse anticipated by this
route of exposure. Get medical attention.

MOST IMPORTANT SYMPTOMS/EFFECTS: May cause skin and eye
irritation. Vapors or mists may cause respiratory irritation. May cause
allergic respiratory reaction in sensitized persons, resulting in wheezing,
shortness of breath, and difficulty breathing.
INDICATION OF IMMEDIATE MEDICAL ATTENTION/SPECIAL
TREATMENT: Required for asthmatic symptoms or serious inhalation
exposures. Respiratory systems, including pulmonary edema, may be
delayed. Persons receiving significant exposure should be observed 24-
48 hours for signs of respiratory distress. Persons sensitized to
Diisocyanates should consult a physician before working with respiratory
irritants or sensitizers.

5. FIRE-FIGHTING MEASURES
EXTINGUISHING MEDIA: Use water fog, foam, carbon dioxide or dry
chemical. Do not use solid water stream. Solid stream of water into hot
product may cause violent steam generation or eruption.
SPECIFIC HAZARDS: Water contamination will produce Carbon Dioxide.
Do not re-seal contaminated containers as pressure buildup may rupture.
SPECIAL PROTECTIVE EQUIPMENT & PRECAUTIONS FOR
FIREFIGHTERS: Wear approved positive pressure, self-contained
breathing apparatus and full body protective clothing.

6. ACCIDENTAL RELEASE MEASURES
PERSONAL PRECAUTIONS, PROTECTIVE EQUIPMENT AND
EMERGENCY PROCEDURES: Clear non-emergency personnel from the
area. Ventilate area. Wear appropriate protective clothing to prevent eye
and skin contact and respiratory protection.
METHODS AND MATERIALS FOR CONTAINMENT AND CLEANUP:
Cover with an inert absorbent material and collect into an appropriate
container for disposal. Do not seal the container since CO2 is generated
on contact with moisture and dangerous pressure buildup can occur.
Decontaminate floor area with a mixture of water plus isopropyl alcohol
(25%), household ammonia (15%), and detergent (5%).

7. HANDLING AND STORAGE
HANDLING: Avoid inhalation of vapors and spray mists. Use in well-
ventilated areas. Avoid contact with skin and eyes. Wash thoroughly after
handling. Do not eat, drink or smoke in the work area. Keep container
closed when not in use.
STORAGE: Store indoors at temperatures between 65F and 75F (18C &
24C). Recommend storage in original, unopened containers. Protect
from atmospheric moisture and water since isocyanates reacts with water
to form CO2, leading to potentially dangerous pressure buildup in sealed
containers.

8. EXPOSURE CONTROL / PERSONAL PROTECTION
OCCUPATIONAL EXPOSURE LIMITS:
CHEMICAL CAS NO. ACGIH TLV/OSHA PEL
4,4-Diphenylmethane Diisocyanate 101-68-8 0.005ppm/0.02ppm (ceiling)
Higher Oligomers of MDI 9016-87-9 0.005ppm/0.02ppm (ceiling)
Chlorinatged Paraffin Hydrocarbon NE NA
(PEL – OSHA Permissible Exposure Limit; TLV ACGIH Threshold Limit
Value; TWA Time Weighted Average; NA-Not Applicable)
VENTILATION: Use with adequate general or local exhaust ventilation to
maintain exposure levels below the occupation exposure limits.

SAFETY DATA SHEET

2
RESPIRATORY PROTECTION: Use an approved respirator with organic
vapor cartridges, if needed. Respirator selection and use should be
based on contaminant type, form and concentration. For any spray
application or situation where airborne particulates or aerosol are
generated, a supplied air source must be provided.
SKIN PROTECTON: Chemical resistant gloves, i.e., natural rubber or
polyvinyl.
EYE PROTECTION: Wear chemical safety goggles.
ENGINEERING CONTROLS: Eyewash stations and safety showers.
OTHER PROTECTIVE MEASURES: All employees should be properly
trained in handling of material.

9. PHYSICAL AND CHEMICAL PROPERTIES
Appearance: Clear Amber to Dark Brown liquid
Odor: Slightly aromatic
Odor Threshold: Not determined
pH: Not applicable
Freezing Point: <60F Melting Point: No data available Boiling Point: No data available Flash Point: 425F (218C) Evaporation Rate: No data available VOC, %: 0 Flammability Limits: No data available Vapor Pressure: <0.0001 mm Hg @ 20C Vapor Density: 8.6 Relative Density: 1.12-1.20 @ 77F (25C) Solubility: Reacts with water Partition Coefficient: n-octanol/water: Reacts with water Auto-ignition Temperature: No data available Decomposition Temperature: 646F (341C) Viscosity: 50-250 cps 10. STABILITY AND REACTIVITY REACTIVITY: Avoid moisture. Isocyanates react with many materials and the rate of reaction increases with temperature. Reaction with water generates carbon dioxide (CO2) and heat. CHEMICAL STABILITY: Stable under recommended conditions. POSSIBILITY OF HAZARDOUS REACTION: Elevated temperatures, over 347F (175C) can cause hazardous polymerization. Polymerization can be catalyzed by strong bases or water. Reaction with water generates carbon dioxide (CO2), and generates heat and pressure in closed systems. CONDITIONS TO AVOID: Avoid moisture and temperatures below 60F (18C) and above 120F (49C). INCOMPATIBLE MATERIALS: Avoid contact with water, acids, bases, alcohols, and strong oxidizers. HAZARDOUS DECOMPOSITION PRODUCTS: Possibly isocyanate vapor, carbon monoxide, nitrogen oxides, and traces of hydrogen cyanide. 11. TOXICOLOGICAL INFORMATION HUMAN EFFECTS OF OVEREXPOSURE Inhalation: May cause respiratory sensitization in susceptible individuals. At room temperature, vapors are minimal due to low volatility. If heated or sprayed as an aerosol, excessive concentrations are attainable that could be hazardous on single exposure. Excessive exposure may cause irritation of the eyes, upper respiratory tract and lungs. Effects may be delayed. Decrease ventilation capacity has been associated with exposure to similar Isocyanates; it is possible that exposure to MDI may cause impairment of lung function. Vapors or aerosols may cause respiratory irritation and possibly pulmonary edema, or respiratory sensitization. For individuals sensitized to MDI, exposure may result in allergic respiratory reactions (e.g., coughing, wheezing, difficulty breathing). Ingestion: Single oral dose toxicity is low. May cause adverse gastrointestinal effects. Skin contact: May cause irritation. Repeated skin contact may cause an allergic skin reaction. Studies in animals indicate skin contact with isocyanates may elicit respiratory sensitization. ACUTE EFFECTS Medical conditions aggravated by exposure: Asthma, other respiratory disorders (bronchitis, emphysema, bronchial hyper- reactivity), skin allergies, eczema. Repeated or prolonged exposure to isocyanates may cause an allergic sensitization of the respiratory tract causing an asthma-like response upon re-exposure. Repeated overexposure to isocyanates has been associated with decreased lung function. Repeated or prolonged dermal contact with this product may cause allergic skin sensitization in some individuals. ACUTE TOXICITY VALUES: Acute Toxicity (Oral): Test Results LD 50 (Rat): >20 g/kg
Acute Toxicity (Dermal): Test Results
LDS 50 (Rabbit): >15.8 g/kg
Acute Toxicity (Inhalation): Test Results
LC 50 (Fish 4hr): approx 370
mg/l
Eyes: Liquids, aerosols, or vapors are irritating and can cause tearing,
reddening, and swelling following contact.
Skin: Can cause skin irritation, which may include the following:
reddening, swelling, rash, scaling, and blistering.
Other: No conclusive evidence has been developed to indicate that MDI
is carcinogenic, teratogenic, or that it causes reproductive effects in
animals and humans.

GERM CELL MUTAGENICITY: Components are not known mutagens.
REPRODUCTIVE TOXICITY: Components are not known reproductive
toxins.
CARCINOGENICITY: MDI is not listed by IARC, NTP or regulated by
OSHA as carcinogens.
SPECIFIC TARGET ORGAN TOXICITY: Single Exposure: No data
available. Repeat Exposure: Tissue injury in the upper respiratory tract
and lungs has been observed in laboratory animals after repeated
excessive exposures to MDI/polymeric MDI aerosols.

12. ECOLOGICAL INFORMATION
ECOTOXICITY: Material is practically non-toxic to aquatic organisms on
an acute basis (LC50/EC50/EL50/LL50>100 mg/L in the most sensitive
species tested). Reacts with water to form insoluble polyureas. Limited
movement in aquatic and terrestrial environments. Not readily
biodegradable and not expected to bioaccumulate.

TEST DURATION ORGANISM
TYPE
TEST RESULTS
Aquatic-Fish Acute
Toxicity
(static)
96 hrs Danio rerio
(zebra fish)
LC50 > 1,000 mg/l:
data for similar
materials
Aquatic-Invertebrate
Acute Toxicity
(static)
24 hrs Daphnia
magna
(water flea)
EC50 > 1,000 mg/l:
data for similar
materials

Aquatic-Plant Acute
Toxicity (static)
Growth rate inhibition
72 hrs Scenedesmus
subspicatus
LL50 >1,640 mg/l:
data for similar
materials

Micro-Organisms
Acute Toxicity (static)
3 hrs Activated
Sludge
EC50 >100 mg/l:
data for similar
materials
Soil Dwelling
Organisms Toxicity
14 days Eisenia foetida
(earthworm)
EC50 > 1,000 mg/kg:
data for similar
materials

BIOACCUMULATION: Movement is expected to be limited due to its
reaction with water forming insoluble polyureas in aquatic and terrestrial
environments.
MOBILITY: No data available due to testing difficulties.
PERSISTANCE AND DEGRADABILITY: Material reacts with water
forming predominantly insoluble polyureas which appear to be stable in
aquatic and terrestrial environments. In the atmospheric environment,
material is expected to have a short tropospheric half-life, based on
calculations and by analogy with related diisocyanates.

13. DISPOSAL CONSIDERATONS
Disposal should be made in accordance with federal, state and local
regulations. When properly mixed with Part B, product forms a non-
hazardous, inert solid. DO NOT DUMP INTO ANY SEWERS, ON THE
GROUND, OR INTO ANY BODY OF WATER.

SAFETY DATA SHEET

3
14. TRANSPORT INFORMATION
Not regulated for transport in any mode.
EMERGENCY SHIPPING: CHEMTREC 1-(800)-424-9300

TECHNICAL SHIPPING NAME: 4,4-Diphenylmethane Diisocyanate

15. REGULATORY INFORMATION
U.S. Federal Regulatory Information
CERCLA 103 Reportable Quantity: This product contains the following
substances subject to reporting and which are listed in 40 CFR 302.4.
CHEMICAL CAS NO. Amount %
4,4-Diphenylmethane Diisocyanate 101-68-8 25 – 60
SARA TITLE III
Section 311, 312: Acute Health-X; Chronic Health-X; Reactive Hazard-X
Section 313 Toxic Chemicals: Product contains the following chemicals
subject for reporting.
CHEMICAL CAS NO. Amount %
4,4-Diphenylmethane Diisocyanate 101-68-8 25 – 60
Higher Oligomers of MDI 9016-87-9 30 – 50

EPA Toxic Substances Control Act (TSCA): All components of this
product are exempt from TSCA Inventory requirements under 40 CFR
720.30.

STATE Regulations
CALIFORNIA PROPOSITION 65:
This product contains no listed substances known to the State of
California to cause cancer, birth defects or other reproductive harm, at
levels that require a warning under the statute.

16. OTHER INFORMATION
HMIS HAZARD IDENTIFICATION:
H-2, F-2, R-1, PP-X
Hazard Rating: 0-Minimal; 1-Slight; 2-Moderate; 3-Serious; 4-Severe; *Chronic Health

NFPA HAZARD IDENTIFICATION:
H-2, F-2, R-1
Hazard Rating: 0-Minimal; 1-Slight; 2-Moderate; 3-Serious; 4-Severe

Training Advice: Train personnel using this product in proper chemical
handling, engineering controls and protective equipment.

Recommended Uses and Restrictions: This product is intended for
industrial/professional use only.

SDS Revision Notes: Updating MSDS to SDS format.

Disclaimer: These data are offered in good faith as typical values and
not as product specifications. No warranty, either expressed or implied, is
made. The recommended industrial hygiene and safe handling
procedures are believed to be generally applicable. However, each user
should review these recommendations in the specific context of the
intended use and determine whether they are appropriate.

Date Prepared/Revised: April 24, 2015; Supersedes: January 11, 2013

SAFETY DATA SHEET

4
1. CHEMICAL AND COMPANY IDENTIFICATION
Product Identifier: HARDCAST B, SILMASTER B, SILPLASTIC B,
SILTOOL B, THERMOCAST II

Use: Component for Polyurethane Casting Plastic;
Professional/Industrial use

Company: SILPAK, INC.
470 EAST BONITA AVE. POMONA, CA 91767
Phone Number: 909-625-0056
Emergency Phone: CHEMTREC 1-(800)-424-9300

Email: silpak@aol.com

2. HAZARDS IDENTIFICATION
GHS HAZARD CLASSIFICATION: NON HAZARDOUS

PRECAUTIONARY STATEMENTS:
Wear protective gloves/ protective clothing/ eye protection/face protection;
Wash thoroughly after handling.

IF ON SKIN: Wash with plenty of soap and water.
IF IN EYES: Rinse cautiously with water for several minutes. Remove
contact lenses, if present and easy to do. Continue rinsing.

SUPPLEMENTAL INFORMATION:
This is one part of a two-component system. Read and understand the
hazard information on Part A before using.

3. COMPOSITION / INFORMATION ON INGREDIENTS

CHEMICAL CAS NO. %
Hydroxyl Terminated Poly
(Oxyalkylene) Polyether
9082-00-2 80-99
Dimethylethanolamine 108-01-0 <1 Triethylenediamine 280-57-9 <1 Other ingredients are not classified as health and/or environmental hazards, and/or are present below cut off/concentration limits 4. FIRST AID MEASURES INHALATION: Remove person to fresh air. Not considered to have any adverse effects. SKIN CONTACT: Remove contaminated clothing. Wash contact area with soap and water. Not considered to have any adverse effects. EYE CONTACT: Rinse thoroughly with water, holding eyelids open to be sure material is washed out. Remove contact lenses if safe and easy to do. Not considered to have any adverse effects. INGESTION: Rinse mouth. Drink water. Induce vomiting only with medical supervision. Not considered to have any adverse effects. MOST IMPORTANT SYMPTOMS/EFFECTS: May cause skin or eye irritation. INDICATION OF IMMEDIATE MEDICAL ATTENTION/SPECIAL TREATMENT: Need for immediate medical attention is not anticipated. 5. FIRE-FIGHTING MEASURES EXTINGUISHING MEDIA: Use water spray, foam, carbon dioxide or dry chemical. SPECIFIC HAZARDS: Combustion products include oxides of carbon and nitrogen. SPECIAL PROTECTIVE EQUIPMENT & PRECAUTIONS FOR FIREFIGHTERS: Wear approved positive pressure, self-contained breathing apparatus and full body protective clothing. Cool fire exposed containers with water. Do not direct solid water stream or foam into hot, burning pools this may cause frothing and increase fire intensity. 6. ACCIDENTAL RELEASE MEASURES PERSONAL PRECAUTIONS, PROTECTIVE EQUIPMENT AND EMERGENCY PROCEDURES: Clear non-emergency personnel from the area. Ensure adequate ventilation. Wear appropriate protective clothing to prevent eye and skin contact. METHODS AND MATERIALS FOR CONTAINMENT AND CLEANUP: Cover with an inert absorbent material and collect into an appropriate container for disposal. Dispose of material according to federal, state, and local regulations. 7. HANDLING AND STORAGE HANDLING: Avoid contact with skin and eyes. Use in ventilated area. Wash thoroughly after handling. Do not eat, drink or smoke in the work area. Keep container closed when not in use. STORAGE: Store indoors at temperatures between 65F and 75F (18C & 24C). Recommend storage in original, unopened containers. Protect from atmospheric moisture and water to prevent moisture contamination. Do not expose to high temperatures for any length of time as aldehydes may be formed. 8. EXPOSURE CONTROL / PERSONAL PROTECTION OCCUPATIONAL EXPOSURE LIMITS: None established VENTILATION: Use with adequate general or local exhaust ventilation to minimize exposure levels. RESPIRATORY PROTECTION: Use an approved respirator with organic vapor cartridges, if needed. Respirator selection and use should be based on contaminant type, form and concentration. For any spray application or situation where airborne particulates or aerosol are generated, a supplied air source must be provided. SKIN PROTECTON: Chemical resistant gloves, i.e., natural rubber or polyvinyl. EYE PROTECTION: Wear chemical safety goggles. ENGINEERING CONTROLS: Eyewash stations and washing facility. OTHER PROTECTIVE MEASURES: None 9. PHYSICAL AND CHEMICAL PROPERTIES Appearance: Clear Amber to Dark Brown liquid Odor: Slightly aromatic Odor Threshold: No data available pH: Not applicable Freezing Point: <32F (0C) Melting Point: No data available Boiling Point: Decomposes Flash Point: 325F (163C) Evaporation Rate: No data available Flammability Limits: No data available Vapor Pressure: Nil Vapor Density: >1.0
VOC: 0
Relative Density: 1.04-1.07 @ 77F (25C)
Solubility: Slightly soluble in water
Partition Coefficient: n-octanol/water: No data available
Auto-ignition Temperature: No data available
Decomposition Temperature: No data available
Viscosity: 100-250 cps

10. STABILITY AND REACTIVITY
REACTIVITY: Not normally reactive.
CHEMICAL STABILITY: Stable under recommended conditions.
POSSIBILITY OF HAZARDOUS REACTION: Reaction with strong
oxidizers generates heat.
CONDITIONS TO AVOID: Excessive heat and exposure to sunlight.
INCOMPATIBLE MATERIALS: Avoid contact with isocyanates and other
substances that react with hydroxyl groups.
HAZARDOUS DECOMPOSITION PRODUCTS: Thermal decomposition
will generate oxides of carbon, aliphatic fragments, and ammonia.

SAFETY DATA SHEET

5
11. TOXICOLOGICAL INFORMATION
HUMAN EFFECTS OF OVEREXPOSURE
INHALATION: No evidence of adverse effects from available information.
INGESTION: No evidence of adverse effects from available information.
SKIN CONTACT: No evidence of adverse effects from available
information.
EYE CONTACT: No evidence of adverse effects from available
information.

CHRONIC HEALTH EFFECTS: None known.
ACUTE TOXICITY VALUES: Mixture has not been tested.
GERM CELL MUTAGENICITY: Components are not known mutagens.
CARCINOGENICITY: Not listed by IARC, NTP or regulated by OSHA as
carcinogens.
REPRODUCTIVE TOXICITY: Components are not known reproductive
toxins.
SPECIFIC TARGET ORGAN TOXICITY: No data available.

12. ECOLOGICAL INFORMATION
ECOTOXICITY: This product as not been tested.
PERSISTENCE AND DEGRADABILITY: No data available.
BIOACCUMULATIVE POTENTIAL: No data available.
MOBILITY IN SOIL: No data available.

13. DISPOSAL CONSIDERATONS
DISPOSAL METHOD: Disposal should be made in accordance with
federal, state and local regulations. Upon disposal, Part B and cured
rubber are not an RCRA hazardous waste (per 40 CFR 261) in the U.S.

14. TRANSPORT INFORMATION
Not regulated for transport in any mode.
EMERGENCY SHIPPING: CHEMTREC 1-(800)-424-9300

TECHNICAL SHIPPING NAME: Polyether Polyol Blend

15. REGULATORY INFORMATION
U.S. Federal Regulatory Information
CERCLA 103 Reportable Quantity: Not subject to reporting. Some
States have more stringent requirements. Report spills in accordance
with local, state and federal regulations.

SARA TITLE III:
Section 311, 312: Not Hazardous
SARA (313) Toxic Chemicals: Product contains no chemicals subject
for reporting.
SARA (302) Extremely Hazardous Substances (TPQ): None

EPA Toxic Substances Control Act (TSCA): All components of this
product are listed on TSCA.

STATE Regulations
CALIFORNIA PROPOSITION 65: This product contains no listed
substances known to the State of California to cause cancer, birth defects
or other reproductive harm, at levels that require a warning under the
statute.

16. OTHER INFORMATION
HMIS HAZARD IDENTIFICATION:
H-2, F-1, R-0, PP-X
Hazard Rating: 0-Minimal; 1-Slight; 2-Moderate; 3-Serious; 4-Severe; *Chronic Health

NFPA HAZARD IDENTIFICATION:
H-2, F-1, R-0
Hazard Rating: 0-Minimal; 1-Slight; 2-Moderate; 3-Serious; 4-Severe

Training Advice: Train personnel using this product in proper chemical
handling, engineering controls and protective equipment.

Recommended Uses and Restrictions: This product is intended for
industrial/professional use only.
SDS Revision Notes: Updating MSDS to SDS format.

Disclaimer: These data are offered in good faith as typical values and
not as product specifications. No warranty, either expressed or implied, is
made. The recommended industrial hygiene and safe handling
procedures are believed to be generally applicable. However, each user
should review these recommendations in the specific context of the
intended use and determine whether they are appropriate.

Date Prepared/Revised: April 24, 2015; Supersedes: January 11, 2013