DURACLEAN LPH

Description:

DURACLEAN LPH is a non-etching type acid cleaner concentrate designed to clean oxides, tarnish, light oils and finger prints from copper substrates without attacking the base metal.

DURACLEAN LPH Acid Cleaner has wide operating latitude, operates near room temperatures, does not attack solvent, aqueous, or semi-aqueous dry film or screen resists, and rinses easily and cleanly.

DURACLEAN LPH when used as part of the DURATECH PROCESS, cleans developed dry film residues from the traces of ANTIOX treated, low speed, thin deposition electroless copper, helping to prepare the board for pattern plate without compromising hole integrity.

Benefits:

• Rapid and complete wetting
• Removes oxides as well as light oils and resist residue
• Leaves a clean, bright surface
• Will not attack solvent or aqueous developed resists
• Will not compromise hole wall integrity of thin dep electroless copper

Properties:

Form:                                                Reddish-yellow liquid
pH (as supplied):                            .8 to 1.2
Specific gravity:                              1.03
Weight/Gallon                                 8.6 lbs
Solubility, water:                             Infinite
Max copper loading:                      .65 gms/liter (650 ppm)
Odor:                                                 None

Applications:

DURACLEAN LPH was designed to perform the difficult function of cleaning photo resist residues from the developed traces of aqueous dry films which have been laminated directly over ANTIOX treated, thin deposition electroless copper, without compromising the copper deposit on the surface or in the holes. DURACLEAN LPH is an excellent low temperature acid cleaner and is ideal for cleaning any copper surface of light oils, tarnish and oxides, where minimal attack on the base metal is desired.

Directions For Use:

MAKE-UP:  50% by volume in water

TIME: 3 - 5 minutes. Do not exceed 5 minutes.

TEMPERATURE: 85°F ± 5°F. Do not operate below 80°F.

AGITATION: None required

OPERATION: Immersion only. Do not spray.

OPTIONAL MAKE-UP: 30% by volume @ 110°F ± 5°F. 20% by volume @ 130° ± 5°F. NOTE: Some aqueous dry film resists are subject to interface attack at elevated temperatures.

Equipment:

TANKS: polypropylene, PVC, PVDC, polyethylene or fiberglass

RACKS: 316 s/s - plastisol coated preferred.

HEATERS: Titanium, quartz, Teflon coated.

Maintenance:

Replace dragout with fresh solution make-up; replace evaporation with water. When oxides are no longer removed within the maximum 5 minute immersion time, and the bath becomes hazy with a strong greenish cast from dissolved copper, it is time to replace the bath (See procedure for analyzing for copper concentration).

Control:

Bath Make-up can be checked by acidity. Bath Life is controlled by copper content.

Analytical procedure for acidity:

1. Equipment:
   1. 150 ml beaker
   2. 5 ml pipet
   3. 50 ml buret
2. Reagents
   1. Sodium Hydroxide, 0.1 Normal (0.1 N NaOH)
   2. pH 7-8 Phenol Red acid-base indicator mixture. (Mallincrodt IndicatAR 7-8).
3. Procedure
   1. Pipe 5 ml of fresh 50% working bath into 150 ml beaker.
   2. Add 100 to 120 ml D.I. water
   3. Add 3 measures of Phenol Red Indicator (.3 to .4 grams)
   4. Titrate with 0.1 N NaOH from a clear yellow to a reddish pink end-point. Change is abrupt. Approach cautiously.
4. Calculations
   1. ml of titrate X Normality X 222 / ml of sample = gms/liter acid
   2. Acidity of a fresh 50% working bath is 23 gms/liter.

Analytical Procedure for Copper Content:

1. Equipment
   1. 250 ml Erlenmyer flask
   2. 10 ml pipet
   3. 50 ml buret
   4. 100 ml measuring cylinder
2. Reagents
   1. 0.01 N Sodium Thiosulfate (Na₂S₂O₂)
   2. Potassium Iodide, AR grade (K1)
   3. Thyodene indicator
3. Procedure
   1. Pipet 10 ml of working bath into 250 ml flask
   2. Add 100 ml of D.I. water
   3. Add 3 grams of KI
   4. Add 0.5 grams Thyodene indicator
   5. Titrate with 0.01 Normal Na₂S₂O₂ from dark brownish-purple color to a pale tan, light colored end-point.
4. Calculations
5. ml of titrate X Normality X 63.5 / ml of sample = gms/liter copper.
6. Grams/liter copper X 1000 = ppm
7. Maximum copper loading = 650 ppm

Special Process Notes:

Do not attempt to clean tin/lead plated boards, or use racks with tin/lead plating on them. The result will be to turn the cleaner into an immersion tin bath, plating tin on copper circuitry. Do not operate bath below 80°F (26.67°C)

Safety:

DURACLEAN LPH is acidic. In case of skin contact flush with copious quantities of cool, fresh water. At the first sign of irritation consult a physician. Wear eye protection at all times. In case of eye contact, flush immediately with cool, fresh water for at least 15 minutes. Consult a physician. In case of ingestion consult a physician immediately.

Disposal:

1. Pump spent solution to a separate treatment tank.
2. Neutralize with Sodium or Potassium hydroxide to a pH of 8 or 9.
3. Add approximately 1/2 lb of Sodium Sulfide or Thiocarbamate to treat 100 gallons of spent solution for removal of metals such as copper, tin, and lead. NOTE: If solution is allowed to become acidic, poisonous hydrogen sulfide gas will form. Do Not let pH drop below 7
4. Filter the treated solution to remove heavy metals. Check solution after filtration by adding Sodium Sulfide to a sample. If no black precipitate forms the solution may be disposed. Heavy metals should be below one ppm after filtration.
5. Check with local city or country sanitation district on disposal to sewer. Generally the only requirements are neutralization to the pH ranch between 6 and 12 and removal of heavy metals. All materials in DURACLEAN LPH are biodegradable and have no effect on waste water treatment systems.

Storage:

Keep containers sealed until needed. Keep partial containers closed at all times. Store product between 40°F and 100°F. Keep away from sources of direct heat. Keep away from alkaline materials and strong oxidizing agents.

Shelf Life:

DURACLEAN LPH is guaranteed for (1) year from date of receipt in unopened containers.

Containers:

Five gallon pails and 55 gallon nonreturnable plastic drums.

Classification:

National Motor Freight Classification NO. 48580, Sub 3
DOT Hazardous Material Description: Compound, cleaning, liquid
Hazard Class: Corrosive Material
I.D. Number: NA 1760

The information contained herein is based on our experience and is believed to be reliable. However, since methods and conditions of use of our products as described are beyond our control, both the product and instructions for its use are offered without warranty, expressed or implied. No information on this data should be construed as a recommendation by DURATECH INDUSTRIES, INC., To use any product in contravention of any patent right.