MIL-STD-202H.pdf - 第213页

MI L - S TD - 202 -2 1 5 4. GENERAL REQUI RE M E N T S 4.1. Material s 4.1.1 Solvent solut io n s . T he s ol v ent s o l ut i ons us ed i n t h i s t es t s ha l l c on s i s t of t he f ol l ow i n g (see tab le I for …

MIL-STD-202-215

METHOD 215

RESISTANCE TO SOLVENTS

1. SCOPE

1.1 Purpose. The purpose of this test is as follows:

a. To verify that markings or color coding will not become illegible or discolored on the parts (including printed

wiring boards) when subjected to solvents and processes normally used to clean solder flux, fingerprints,

and other contaminants from printed-wiring and terminal-board assemblies, etc.

b. To verify that component protective coatings and encapsulant materials are not degraded to the point

where electrical or mechanical integrity is disturbed when subjected to solvents and processes normally

used to clean solder flux, fingerprints, and other contaminants from printed wiring and terminal board

assemblies, etc.

1.2 Formulation of solvents. The formulation of solvents is considered typical and representative of the solvents

used in printed wiring assembly processing of electronic components. Processing conditions are representative of

processes used for printed wiring assembly.

1.3 Checks for conflicts. When this test is referenced, care should be exercised to assure that conflicting

requirements, as far as the properties of the specified finishes and markings are concerned, are not invoked.

2. APPLICABLE DOCUMENTS

2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part

of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those

cited in the solicitation or contract.

FEDERAL SPECIFICATIONS

TT-I-735 - Isopropyl Alcohol

DEPARTMENT OF DEFENSE SPECIFICATIONS

MIL-PRF-680 - Degreasing Solvent

(Copies of these documents are available online at http://quicksearch.dla.mil)

3. DEFINTIONS

This section not applicable to this standard.

北测（上海）电子科技有限公司

联系方式：xuyj@beice-sh.com 13917165676

MIL-STD-202-215

4. GENERAL REQUIREMENTS

4.1. Materials

4.1.1 Solvent solutions. The solvent solutions used in this test shall consist of the following (see table I for

summary).

a. A mixture consisting of the following:

1. One part by volume of isopropyl alcohol, American Chemical Society (ACS) reagent grade, or isopropyl

alcohol in accordance with TT-I-735, grade A or B, and

2. Three parts by volume of mineral spirits in accordance with MIL-PRF-680, type I, or three parts by volume of

a mixture of 80 percent by volume of kerosene and 20 percent by volume ethylbenzene.

b. This solvent has been deleted. When a suitable replacement solvent has been determined, it will be added as

solution b.

c. A terpene defluxer consisting of a minimum of 90 percent d-limonene and 10 percent surfactant. 1/

d. A mixture consisting of the following:

1. Forty-two parts by volume water, 1 megohm-cm minimum resistivity.

2. One part by volume of propylene glycol monomethyl ether (glycol ether PM, 1-methoxy-2-propanol).

3. One part by volume of monoethanolamine. 2/

4.1.1.1 Solvent solutions, safety aspects. Solvent solutions listed in 4.1.1a through 4.1.1d exhibit some potential

for health and safety hazards. Safety precautions as listed in the appropriate manufacturers material safety data

sheet shall be observed.

4.1.2 Vessel. The vessel for solvent immersion shall be a container made of non-reactive material and of sufficient

size to permit complete immersion of the specimens in the solvent solutions specified in 4.1.1.

4.1.3 Brush. The brush shall be a toothbrush with a handle made of a non-reactive material. The brush shall have

three or four long rows, 1 and 1/8 ±1/8 inch in length, of hard bristles. Each row shall contain eight to twelve tufts, the

free ends of which shall lie substantially in the same plane. The brush shall be used with a single solvent and when

there is any evidence of softening, bending, wear, or loss of bristles, it shall be discarded.

1/ A commonly used terpene defluxer is BIOACT EC-7R. "BIOACT" is a registered Trademark of Petroferm INC;

"EC-7 and EC-7R" are trademarks of Petroferm INC.

2/ Normal safety precaution for handling this solution (e.g., same as those for diluted ammonium hydroxide)

based on O.S.H.A. rules for monoethanolamine.

北测（上海）电子科技有限公司

联系方式：xuyj@beice-sh.com 13917165676

MIL-STD-202-215

4.2. Procedure

4.2.1 Groups. The specimens subjected to this test shall be divided into three groups of approximately equal size.

a. The first group shall be exposed to the solution specified in 4.1.1a.

The solution shall be maintained at a temperature of 25°C ±5°C. The specimens shall be completely

immersed for 3 minutes +0.5, -0 minutes in the specified solution contained in the vessel specified in 4.1.2.

Immediately following immersion, each specimen shall be tested as follows: The bristle portion of the brush,

specified in 4.1.3, shall be dipped in the solution until wetted and the specimen shall be brushed with normal

hand pressure (approximately 2 to 3 ounce force applied normal to the surface) for ten strokes on the portion of

the specimen where marking has been applied. The brush stroke shall be directed in a forward direction across

the surface of the specimen being tested. Immediately after brushing, the procedure shall be repeated two more

times, for a total of three immersions, followed by brushing. After completion of the third immersion and

brushing, the specimens shall be air-blown dry. The specimens shall be inspected in accordance with 5.2.1 and

5.2.2 to determine the extent, if any, of deterioration that has occurred.

b. This solvent solution has been deleted.

c. The second group shall be exposed to the solution specified in 4.1.1c.