Silver Solder Paste Safety Data Sheet

The following safety data information is provided by the manufacturer of this product. Please read thoroughly and do not hesitate to contact us if you need further information. The information provided in this Safety Data Sheet is correct to the best of our knowledge, information and belief at the date of its publication.

1. Product Name: STL-1267E-XXX (A30 Easy Solder Paste), STL-1274M-XXX (A30 Medium Solder Paste) & 1274M Filler Metal: 720-765oC [1328-1409oF] (A30 Hard Solder Paste).

Product Description & Use: A braze paste consisting of powdered filler metal and flux suspended in a binder and used for joining metals by heating the parts to be joined and this product to or above the melting temperature of the filler metal.

2. Hazard Identification
"T" - Toxic
R20/22: Harmful by inhalation and if swallowed.
R36/38: Irritating to eyes and skin.
R60: May impair fertility.
R61: May cause harm to the unborn child.

Emergency Overview: IMMEDIATE CONCERNS: Warning! Product contains fluorides: In use above 500oC [930oF] in the presence of water vapor, hydrogen fluoride gas is evolved. Hydrogen fluoride gas can cause irritation to the respiratory tract, and delayed burns to the eyes and skin. It can also cause fluid in the lungs [pulmonary edema], and death. Avoid contact with skin, eyes, and inhalation of vapors. 
Fumes from the soldering/brazing process are irritating to the eyes and respiratory system. Hot metal can cause eye and skin burns. Avoid breathing fumes from the soldering/brazing process. Use only with adequate ventilation.

Potential Health Effects: 

Eyes: Can cause severe irritation and abrasion. [Contains metal powder and fluoride salts].
Skin: Flux ingredients: Skin contact may cause: severe irritation, burns. Prolonged skin contact may lead to symptoms similar to ingestion. May cause skin irritation. Hot molten metal may cause burns to the skin. Wear protective equipment when working with molten metal.
Ingestion: Flux ingredient(s): Fluorides: Can severely irritate and burn the mouth, throat and stomach. Toxic and possibly
fatal if swallowed. Symptoms include: salivation, nausea, vomiting, diarrhea, abdominal pain, and coma. Ingestion may cause systemic poisoning. Solvent: Harmful if swallowed. Silver: Prolonged ingestion of silver compounds may cause a permanent bluish discoloration of the skin, eyes, and mucous membranes. Copper: Ingestion may cause nausea, vomiting, diarrhea. Zinc: Ingestion of soluble salts of this material may cause abdominal irritation resulting in nausea and vomiting.
Inhalation: Flux ingredient(s): Fluoride fume can cause respiratory irritation and pulmonary edema. Solvent: Excessive
vapor inhalation will lead to central nervous system depression. Silver: Prolonged inhalation of silver compounds may cause a permanent bluish discoloration of the skin, eyes, and mucous membranes. Copper: If inhaled, may cause sneezing, nausea, weakness, fever. Fumes from heating may cause metal fume fever. Zinc: This material is relatively non-toxic to humans by inhalation. However, acute overexposure to zinc oxide fume may cause metal fume fever, characterized by flulike symptoms such as chills, fever, nausea and vomiting..

Signs & Symptoms of Overexposure:

Acute Toxicity: Boric Acid: Symptoms of over-exposure include nausea, vomiting and diarrhea. Acute overexposure to zinc
oxide fume evolved from heating this product may cause metal fume fever, characterized by flu-like symptoms such as chills, fever, nausea and vomiting.
Chronic Effects: Flux ingredients: Repeated exposure to fluoride containing dust can result in embrittlement and
decalcification of bones and increased calcification of ligaments and vertebrae [fluorosis], stiffness and limitation of motion can result. Symptoms of fluorosis include brittle bones, weight loss, anemia, calcified ligaments, general ill health, joint stiffness, mottling of teeth, and bone damage [osteosclerosis]. Solvent: Material may defat the skin on repeated exposure leading to dermatitis. Silver: Chronic exposure may produce argyria, a permanent blue-gray discoloration of the skin, eyes, mucous membranes and respiratory tract. Skin contact with silver powder produces localized irritation and/or argyria. Copper: Prolonged or repeated exposure to the metal may cause: skin and hair discoloration, skin irritation, dermatitis, runny nose, irritation of the mucous membranes. Repeated ingestion may cause: damage to liver, kidneys. Repeated inhalation may cause chronic respiratory disease.
Carcinogenicity: The materials used to formulate this product are not listed as a carcinogen by NTP, IARC, OSHA or the UK HSC.
Reproductive Toxicity: Reproductive Effects: Animal ingestion studies in several species, at high doses, indicate that borates cause reproductive and developmental effects. A human study of occupational exposure to borate dust showed no adverse effect on reproduction.
Medical Conditions Aggrivated: Persons with pre-existing disorders of the liver, kidney, pulmonary function or having
Wilson's disease may be more susceptible to the effects of this material.
Routes Of Entry: Potential routes of entry include: eye contact, skin contact, inhalation of metallic fume and decomposition
products from heating this material during the soldering/brazing process.
Target Organ Statement: Affected target organs: eyes, skin, central nervous system, respiratory system, reproductive
system, bones (fluorosis), calcification of ligaments and vertebrae, teeth, liver, kidneys, mucous membranes, conjunctiva.
Health Hazards: Fluorides can cause eye, skin, and respiratory tract irritation. Overexposure to fluoride dust over prolonged
periods can result in fluoride deposition in bones and cartilage as evidenced by X-ray changes [fluorosis] which may be
accompanied by stiffness of joints.

In use above 500°C [930°F] in the presence of water vapor, hydrogen fluoride gas is evolved. Hydrogen fluoride gas can cause irritation to the respiratory tract, and delayed burns to the eyes and skin. It can also cause fluid in the lungs [pulmonary edema], and death.

3. Composition / Information on Hazardous Ingredients for Easy Solder Paste

Chemical Name CAS EINECS Classification Content
C520 - - T,C; R25,R34 -
Boric Acid 10043-35-3 233-139-2 T; Repr Cat.
2, R60, R61
0.1 - 15
C039 - - - -
Silver 7440-22-4 231-131-3 - 40.02 - 63.37
Copper 7440-50-8 231-159-6 - 13.98 - 22.14
Zinc 7440-66-6 231-175-3 - 6 - 9.5

Comments: 1267E Alloy: Filler Metal Composition [nominal]:

Element Weight %
Silver 66.7
Copper 23.3
Zinc 10


Composition / Information on Hazardous Ingredients for Medium Solder Paste

Chemical Name CAS EINECS Classification Content
C520 - - T,C; R25,R34 -
Boric Acid 10043-35-3 233-139-2 T; Repr Cat.
2, R60, R61
0.1 - 15
C039 - - - -
Silver 7440-22-4 231-131-3 - 44.4 - 70.3
Copper 7440-50-8 231-159-6 - 11.52 - 18.24
Zinc 7440-66-6 231-175-3 - 4.08 - 6.46

Comments: 1274M Alloy: Filler Metal Composition [nominal]:

Element Weight %
Silver 74
Copper 19.2
Zinc 6.8


Composition / Information on Hazardous Ingredients for Hard Solder Paste

Chemical Name CAS EINECS Classification Content
C520 - - T,C; R25,R34 -
Boric Acid 10043-35-3 233-139-2 T; Repr Cat.
2, R60, R61
0.1 - 15
C039 - - - -
Silver 7440-22-4 231-131-3 - 40.02 - 63.37
Copper 7440-50-8 231-159-6 - 17.58 - 27.84
Zinc 7440-66-6 231-175-3 - 2.4 - 3.8

Comments: 1267H Alloy: Filler Metal Composition [nominal]:

Element Weight %
Silver 66.7
Copper 29.3
Zinc 4

The specific chemical identity of the flux/binder formulation ingredients are being withheld as a trade secret. Disclosure will be provided to medical personnel in the event of an emergency. See Section 8 for exposure limits of hazardous ingredients [where applicable]. *** See Paste Spec Sheet for nominal alloy percentages.
( Full text of R-Phrases can be found under heading 16 )

4. First Aid Treatment

Eyes: Immediately flush eyes with plenty of low-pressure water for at least 15 minutes. Get medical attention if irritation persists.
Skin: Immediately remove contaminated clothing. Do not attempt to remove any material bonded to the skin. Flush area of skin contact immediately with large amounts of water for at least 15 minutes. If irritation persists after flushing, get medical attention promptly. Launder contaminated clothing before reuse.
Ingestion: If swallowed: Do not induce vomiting unless instructed to do so by medical personnel. Never give anything by mouth to an unconscious person. Get medical attention immediately.
Inhalation: Remove victim to fresh air. If not breathing, trained personnel may give artificial respiration. If breathing is difficult, give oxygen by trained personnel. Seek medical attention.
Notes To Physician: Fluorides can reduce serum calcium levels resulting in potentially fatal hypocalcemia. Potassium can
reduce blood pressure and cause coma. Boric Acid: Observation only is required for adult ingestion in the range of 4-8 grams of this material. For ingestion of larger amounts, maintain adequate kidney function and force fluids. Gastric lavage is recommended for symptomatic patients only. Hemodialysis should be reserved for massive acute ingestion or patients with renal failure. Boron analyses of urine or blood are useful only for documenting exposure and should not be used to evaluate severity of poisoning or to guide treatment..

5. Fire Fighting Measures

Flammable Class: Non-flammable solid
Extinguishing Media: For fires involving this product, use dry chemical, carbon dioxide, foam, water spray. Do not use water if metal is molten.
Explosion Hazards: Emits toxic and corrosive fumes under fire conditions.
Fire Fighting Procedures: Move container from fire area if it can be done without risk. Avoid inhalation of vapors or mists.
Fire Fighting Equipment: Exposure to decomposition products may be a hazard to health. Do not breathe smoke, gases or vapors generated. Wear goggles if eye protection is not provided. Wash away any material that comes into contact with the body, clothing or equipment. When fighting fires involving this product, wear full protective gear. For fires in enclosed areas, fire fighters must use selfcontained breathing apparatus.
Hazardous Decomposition Products: Decomposition products may include: carbon monoxide, carbon dioxide, smoke.
When heated to decomposition temperatures [>225°C / 437°F], highly corrosive and toxic hydrofluoric acid fumes may be
generated. Metallic decomposition products may include: metal oxide fumes, copper fume, zinc oxide fumes.

6. Accidental Release Measures

General Procedures: Waste disposal method: Scoop up excess material and wash affected areas with soap and water. Avoid contact with skin and eyes.
Special Protective Equipment: Avoid inhaling vapor and/or mists. Do not get spilled material on skin, clothing, or in eyes. Wear full protective clothing. See Section 8. Remove all contaminated clothing.

7. Handling & Storage

Handling: Keep away from sources of ignition. 
Storage: Keep lid tightly closed except when removing product and store at ambient temperatures of 5-25°C [41-77°F] [to maximise shelf life of product]. 

8. Exposure Controls / Personal Protection

Ingredients with Occupational Exposure Limits To Be Monitored At The Workplace:

CAS Chemical Name   UK WEL
- C520 LTEL (TWA) 2.5 mg/m³
fluorides, as F)
10043-35-3 Boric Acid LTEL (TWA) Respirable
Dust -
- C039 LTEL (TWA) 5 mg/m³ [OSHA
7440-22-4 Silver LTEL (TWA) 0.1 mg/m³
7440-50-8 Copper





0.2 mg/m³ [fume,
as Cu]
Respirable Dust -
1mg/m³[dusts &
mists, as Cu]

2 mg/m³ [dusts &
mists, as Cu]

7440-66-6 Zinc





10 mg/m³ [zinc
oxide fume]
UK WEL applies]

10 mg/m³ [zinc 
oxide fume]
UK WEL applies]

Engineering Controls: The use of local ventilation is required to maintain the concentration of fumes evolved from the
soldering/brazing process to well below the occupational exposure limits, within the operator's breathing zone and the general vicinity. Use of process enclosures, exhaust systems, and other engineering/administrative controls should be designed in accordance with local conditions. Please refer to the ACGIH document, Industrial Ventilation, A Manual of Recommended Practices [most recent edition], for details.

Eyes and Face: Wear safety glasses with side shields as a minimum level of protection. Consult ANSI Z87.1 for more information.
Skin: Wear chemical resistant gloves. When material is heated, wear thermal-insulated gloves to protect against burns.
Respiratory: When exposure limits (listed above) are exceeded or ventilation is inadequate, wear a NIOSH or European
Standard approved respirator, in accordance with OSHA respirator regulations [29 CFR 1910.134] or European Standards
[EN149]. Consult ANSI Z88.2 American National Standard for Respiratory Protection for guidance on proper selection, use
and care of respirators.
Protective Clothing: Avoid skin contact. Wear chemical resistant clothing ( long-sleeved shirt buttoned at the wrist) as necessary to prevent contact. For soldering/brazing operations where hot metallic parts are handled and molten metal may be present, wear heatresistant gloves and clothing to protect from burns.
Work Hygienic Practices: Minimize exposure in accordance with good hygiene practice. Good general hygienic practices include: Eating, drinking, and smoking should not be permitted in work areas. Wash thoroughly after handling, and before eating, drinking, using tobacco, applying cosmetics, or using the toilet. Keep area clean. Remove contaminated clothing promptly. Launder contaminated clothing before reuse. Avoid contact with eyes, skin, and clothing. Avoid breathing dust, vapor or mist.
Other Precautions: Educate and train employees in the safe use and handling of this product.

9. Physical and Chemical Properties

Flashpoint and Method: Not Applicable
Odor: Characteristic odor
Appearance: Viscous paste
Colour: Gold
Vapor Pressure: 0.093 mm Hg at 68°F/20°C [for C039]
Vapor Density: >1 [air=1] [for C039]
Boiling Point: 530-623°F [277-328°C] [for C039]
Solubility In Water: Negligible
Evaporation Rate: No data available
Specific Gravity: > 2.000 (water=1)

Easy Melting Point: 1267E Filler Metal: 705-723°C [1301-1333°F]
Medium Melting Point: 1274M Filler Metal: 720-765°C [1328-1409°F]
Hard Melting Point: 1267H Filler Metal: 745-778°C [1373-1432°F]

10. Stability and Reactivity

Stability: Stable under normal conditions of use.
Polymerization: Will not occur.
Conditions To Avoid: Avoid contact with incompatible materials. Avoid extreme heat. Avoid prolonged exposure to air and moisture.
Incompatible Materials: Materials to avoid: strong oxidizers, acids [produces HF gas], reaction with strong reducing
agents [metal hydrides or alkali metals] will generate hydrogen gas, halogens, strong alkalies, chlorine, peroxides, strong acids, strong bases, acetylene, ammonia, halogenated hydrocarbons, magnesium, bromates, chlorates, iodates.

11. Toxicological Information


Chemical Name Oral LD50
Dermal LD50
LC50 (rat)
Boric Acid 3500 to 4100
mg/kg [rat]
> 2000 mg/kg
> 2.0 mg/L/4 hr.
Copper 152 mg/kg [rat] - -

Notes: If excessive quantities of zinc oxide fume are inhaled, it can result in the condition called metal fume fever. The
symptoms of metal fume fever will occur within 3 to 10 hours, and include immediate dryness and irritation of the throat,
tightness of the chest, and coughing which may later be followed by flu-like symptoms of fever, malaise, perspiration, frontal headache, muscle cramps, low back pain, occasionally blurred vision, nausea, and vomiting. There are no recognized complications, after effects, or chronic effects that result from this condition.

Eye Effects: Can cause severe irritation and abrasion. [Contains metal powder and fluoride salts.]
Skin Effects: May cause severe irritation. 
Chronic: The fluoride ion can reduce serum calcium levels, possibly causing fatal decalcification of the bones.
Zinc: There is no chronic form of metal fume fever but in rare instances an acute incident may be followed by compliants such as bronchitis or pneumonia. Some workers may develop a short-term immunity [resistance] so that repeated exposure to zinc oxide fumes does not cause metal fume fever. This immunity [resistance] however is quickly lost after short absences from work [weekends or vacations]. Workers exposed to finely divided metallic zinc for up to 35 years revealed no acute or chronic illnesses attributable to zinc.


Chemical Name NTP Status General Toxicity
Boric Acid Not listed
as a carcinogen.
EU Repr Cat 2:
May impair fertility. May
cause harm to the unborn child.

Notes: This product was not formulated with any ingredients that are classified as carcinogenic by IARC, NTP, ACGIH, OSHA or the UK HSC.

12. Ecological Information: Distribution: Ecological information on this product and its ingredients is not known.

13. Disposal Considerations

Disposal Method: Dispose of in accordance with EC, national and local regulations, or sell to a refiner. 
Product Disposal: Disposal of waste material from the use of this product may be subject to federal, state and local regulations. Waste characterizations and compliance with applicable laws are the sole responsibility of the waste generator. Reclaimed scrap metal has monetary value. Contact a commercial reclaimer for information on recycling scrap metals. All recovered material should be packaged, labeled, transported and disposed or reclaimed in conformance with applicable laws and regulations and in conformance with good engineering practices.
Empty Container: Do not reuse empty containers. Dispose of empty container in accordance with EC, national and local regulations.

14. Transport Information: Not restricted for transport. 

15. Regulatory Information 


Chemical Name CAS EINECS
Boric Acid 10043-35-3 233-139-2

EEC CLASSIFICATION [overall preparation]

"T" - Toxic
R20/22: Harmful by inhalation and if swallowed.
R36/38: Irritating to eyes and skin.
R60: May impair fertility.
R61: May cause harm to the unborn child.
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
S36/37: Wear suitable protective clothing and gloves.
S45: In case of accident or if you feel unwell, seek medical advice immediately (show the label where
S51: Use only in well-ventilated areas.
S53: Avoid exposure — obtain special instructions before use.

16. Other Information

Relevant R-Phrases [for Hazardous Ingredients]: 
R25: Toxic if swallowed.
R34: Causes burns.
R60: May impair fertility.
R61: May cause harm to the unborn child.
Approved By: Regulatory Affairs
Prepared By: Jerishia D. Holly
Information Contact: Regulatory Affairs


Manufacturer Disclaimer: This Material Safety Data Sheet is prepared in accordance with U.S. OSHA, Canadian WHMIS,
and European Community Safety Data Sheet directives. This document is offered pursuant to OSHA's Hazard Communication Standard 29 CFR 1910.1200. The information and recommendations contained in this Material Safety Data Sheet have been compiled from sources believed to be reliable and to represent the most reasonable current opinion on the subject when the MSDS was prepared, and are offered in good faith. However, no warranty, guaranty or representation is expressed or implied as to the correctness or sufficiency of the information. The user of this product must decide what safety measures are necessary to safely use this product, either alone or in combination with other products, and determine its environmental regulatory compliance obligations under any applicable EC, national or state laws. Fusion, Incorporated assumes no responsibility for injury to the end user caused by the material even if proper safety procedures are followed. The end user should determine the suitability of the information for their particular usage. The end user assumes the risk in the use of this material. The information in this document may be changed periodically. Contact Fusion to determine if you possess the most current version of the document.

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