1、SSPC-Paint 23November 1, 1982Editorial Revisions November 1, 200469SSPC: The Society for Protective CoatingsPAINT SPECIFICATION NO. 23Latex Primer for Steel Surfaces1. Scope1.1 This specifi cation covers an air drying, ready-mixed, water-borne primer for blast cleaned steel. It is intended for use a
2、s a primer coat of a water-borne coating system consisting of two coats of this primer and one or two coats of a water-borne topcoat.1.2 This primer is suitable for exposures in Environmental Zones 1A (interior, normally dry) and 1B (exterior, normally dry), and is intended for brush, spray, or roll
3、er application over steel surfaces prepared in accordance with SSPC-SP 6, “Commercial Blast Cleaning.” It is suitable as a shop primer, fi eld primer, maintenance primer, or intermediate coat and is to be applied in accordance with SSPC-PA 1, “Shop, Field, and Maintenance Painting of Steel.” It is n
4、ot recommended to expose steel to the weather with less than two coats of water-borne coating; therefore, intermediate and topcoats should be applied as soon as possible.2. Description2.1 This primer is based on a latex vehicle produced by emulsion polymerization and appropriate pigments. Details of
5、 the composition are given in Table 1.2.2 This primer contains approximately 36% by volume of nonvolatile fi lm-forming solids (pigment and binder). The theoretical spreading rate for a 2.0 mil (51 micrometers) dry fi lm thickness is 290 square feet/U.S. gallon (7.1 square meters/liter). Actual spre
6、ading rates can be signifi cantly lower.3. Referenced Standards3.1 The latest issue, revision, or amendment of the refer-enced standards in effect on the date of invitation to bid shall govern, unless otherwise specifi ed. 3.2 If there is a confl ict between the requirements of any of the cited refe
7、renced standards and this specifi cation, the requirements of this specifi cation shall prevail.3.3 SSPC STANDARDS AND JOINT STANDARDS:SSPC Guide 13 Guide for the Identifi cation and Use of Industrial Coating Material in Computerized Product DatabasesPA 1 Shop, Field, and Maintenance Painting of Ste
8、elPaint 24 Latex Semigloss Exterior Top-coatSP 6/NACE No. 3 Commercial Blast CleaningVIS 2 Guide and Reference Photographs for Evaluating the Degree of Rust-ing on Steel Surfaces3.4 ASTM INTERNATIONAL STANDARDS:B 117 Method of Salt Spray (Fog) TestingD 522 Test Methods for Mandrel Bend Test of Attac
9、hed Organic CoatingsD 523 Test Method for Specular GlossD 562 Test Method for Consistency of Paints Measuring Krebs Unit (KU) Viscosity Using a Stormer-type ViscometerD 609 Practice for Preparation of Cold-Rolled Steel Panels for Testing Paint, Varnish,Conversion Coatings, and Related Coating Produc
10、tsD 610 Test Method for Evaluating Degree of Rust-ing on Painted Steel SurfacesD 714 Test Method for Evaluating Degree of Blistering of PaintsD 1210 Test Methods for Fineness of Dispersion of Pigment-Vehicle Systems by Hegman-type GageD 1296 Test Method for Odor of Volatile Solvents and DiluentsD 16
11、40 Test Methods for Drying, Curing, or Film Formation of Organic Coatings at Room TemperatureD 1654 Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environ-mentsD 1737 (Canceled) Elongation of Attached Organic Coatings with Cylindrical Mandrel Apparatus (Replaced with AST
12、M D522)D 1849 Test Method for Package Stability of PaintD 2243 Test Method for Freeze-Thaw Resistance of Water-Borne CoatingsD 2247 Practice for Testing Water Resistance of Coatings in 100% Relative HumidityD 2486 Test Method for Scrub Resistance of Wall PaintsD 2574 Test Method for Resistance of Em
13、ulsion Paints in the Container to Attack by Micro-organismsSSPC-Paint 23November 1, 1982Editorial Revisions November 1, 200470D 2801 (Withdrawn) Test Method for Leveling Char-acteristics of Paints by Draw-Down Method (See ASTM D 4400.)D 3273 Test Method for Resistance to Growth of Mold on the Surfac
14、e of Interior Coatings in an Environmental ChamberD 3274 Test Method for Evaluating Degree of Surface Disfi gurement of Paint Films by Microbial (Fungal or Algal) Growth or Soil and Dirt AccumulationD 3891 Standard Practice for Preparation of Glass Panels for Testing Paint, Varnish, Lacquer, and Rel
15、ated ProductsD 3925 Practice for Sampling Liquid Paints and Related Pigmented CoatingsD 4400 Test Method for Sag Resistance of Paints Using a Multinotch Applicator3.5 FEDERAL STANDARDS:TT-E-506 Enamel, Alkyd, Gloss, Tints and White (for Interior Use)FED-STD-141 Paint, Varnish, Lacquer and Related Ma
16、terials: Methods of Inspection, Sampling and Testing Method 2021 (Canceled) Preparation of Glass Panels (Use ASTM D 3891)Method 6141.1 (Canceled) Washability3.6 AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) STANDARD:Z129.1 Hazardous Industrial ChemicalsPrecautionary Labeling4. Composition4.1 The manu
17、facturer is given some latitude in the selec-tion of materials and process of manufacture, provided that the primer meets the requirements of this specifi cation. Materials shall be of the best quality used in good commercial practice and entirely suitable for the purpose intended under normal condi
18、tions of use.4.2 The vehicle shall be a stable dispersion of synthetic resin particles (latex) in water prepared by emulsion polymer-ization, together with the necessary additives such as pigment dispersant, antifoamer, preservatives, and “antifreeze” in order to produce a primer conforming to this
19、specifi cation. A suitable fi lm and package preservative shall be used.4.3 The paint shall conform to the composition (analysis) requirements of Table 1.5. Properties5.1 The paint shall meet the requirements of Table 2 and Sections 5.2 through 5.17.5.2 ODOR: Shall be normal for the materials permit
20、ted (ASTM D 1296). In a freshly opened container, there shall be no offensive, disagreeable, or putrid odor.5.3 COLOR: The color shall be as specifi ed in the procure-ment documents.5.4 RESISTANCE TO MICROORGANISM ATTACK: The paint shall be resistant to attack by microorganisms when tested according
21、 to ASTM D 2574.5.5 APPLICATION PROPERTIES: The paint shall be easily applied to a smooth steel vertical surface at 4 mils (102 micrometers) wet fi lm thickness on 400 square feet/gallon (9.8 square meters/liter) by brush, spray, or roller. Drying shall be done in a well-ventilated room or chamber f
22、ree from drafts and dust in diffused light, not in direct sunlight. The temperature of the air shall be between 21 and 28C. The relative humidity shall be 50% 5%. There shall be no runs, sags, streaks, fl ashes, laps, pinholing, eyeing, or cratering. After four hours of drying, apply a second coat i
23、n the same manner as the fi rst. There shall be no picking-up or rolling-up of the fi rst coat during applications. After 24 hours, the fi lm shall be smooth and uniform.5.6 CONDITION IN CONTAINER: The primer as received shall show no evidence of livering, skinning, or hard settling of the pigment.
24、The inside of the container shall not be corroded. The material shall be easily dispersed in the liquid portion by hand stirring to form a smooth homogeneous paint. The primer shall show a minimum of foaming and be free of grit, seeds, lumps, or livering.5.7 FREEZE-THAW RESISTANCE: The paint shall p
25、ass three cycles when tested according to the procedure described in ASTM D 2243. There shall be no gelation, or excessive thick-ening, coagulation, lumps, or coarse particles. The maximum allowable increase or decrease in viscosity shall not exceed 10 Kreb units.5.8 WET ADHESION: Prepare 6“ x 17“x
26、1/4“(15 cm x 43 cm x 0.63 cm) glass panels with a ground surface which has been cleaned according to FED-STD-141, Method 2021. Apply alkyd enamel conforming to Federal Specifi cation TT-E-506 by drawndown with a suitable applicator to obtain a dry fi lm thickness of 3.0 0.3 mils (76 8 micrometers) a
27、nd a width of 5-1/2“ (14 cm). Allow the alkyd enamel to dry in a horizontal position for three days at 74-80F (23-27C) and 50% 5% relative humidity. Bake two hours at 200F (93C) prior to the application of the test paint. Apply the test paint by drawdown as above in a direction perpendicular to the
28、long axis of the SSPC-Paint 23November 1, 1982Editorial Revisions November 1, 200471panel to obtain a dry fi lm of 2.0 0.2 mils (51 5 micrometers) and a width of approximately 2 inches (5 cm). Allow the test paint to dry for 48 hours at 74-80F (23-27C) and 50% 5% relative humidity.Make a cut (the en
29、tire width of the test panel) perpendicular to the long axis of the glass panel through the center of the test fi lm with a razor blade held at a 45-degree angle. Place the panel on a Gardner Machine (described in FED-STD-141, Method 6141) so that the test paint is approximately in the center of the
30、 brush stroke and scrub underwater with the brush described in ASTM D 2486. A brush shall move in a direction parallel to the long axis of the glass panel and perpendicular to the cut made in the test fi lm. The brush shall travel at a rate of 39 1 cycles (78 2 separate strokes) per minute. There sh
31、all be no adhesion failure between the test paint and the alkyd undercoat after 1,500 strokes. The paint may wear through to the alkyd enamel in less than 1,500 strokes. If this occurs, it shall not be considered as adhesion failure of the test paint.5.9 PACKAGE STABILITY: Perform the following test
32、s in accordance with ASTM D 1849. When stored for one month at 123 to127F (51 to 53C), the maximum allowable increase or decrease in viscosity shall not exceed 10 Kreb units. After brushing, the fi lm shall be free from grains, lumps, or streaks.5.10 MECHANICAL STABILITY: Fill a one quart (one liter
33、) friction top can three-quarters full with the primer and close the can tightly. Rotate on a jar roller for 168 hours at 120 to 170 rpm. At the end of 168 hours, there shall be no indication of separation, coagulation, excessive thickening or loss in mechanical stability. The maximum allowable incr
34、ease or decrease in viscosity shall not exceed 10 Krebs units.5.11 COALESCENCE TEST: Apply the primer to two 4“ x 8“ (10 cm x 20 cm) cold-rolled steel panels to produce a dry fi lm thickness of 2.0 0.5 mils (50 13 micrometers).(a) Allow one panel to dry for four hours at 50% 5% relative humidity and
35、 at 47 to 53F (8 to 12C).(b) Allow the other panel to dry four hours at the same relative humidity as the fi rst and at 74 to 80F (23 to 27C).At the end of the four-hour drying period, allow both panels to remain at condition (b) above for 24 hours. At the end of 24 hours, brush one coat of alkyd en
36、amel conforming to Federal Specifi cation TT-E-506 to one-half of each panel. The enamel shall be tinted with lampblack to 45% to 55% apparent daylight Pigment Volume Concentration 22 35 Nonvolatile Vehicle 20 Total Solids by Volume 36 Oil or Resin Modifi ers inNonvolatile Vehicle, wt. 40 1Theoretic
37、al as calculated.TABLE 1ANALYSISCHARACTERISTICS1Min. % Max. % ASTM FED-STD-141 REQUIREMENTSViscosity1shear rate 200 rpmGrams 150 240 D 562 Kreb units 72 88 D 562 Fineness of grind, Hegman units 3.0 D 1210 Drying time, hoursDry to touch 4 D 1640 Dry hard 24 D 1640 60 degrees Specular Gloss 25 D 523 S
38、ag Resistance, mils 6 D 280121 Viscosity 48 hours or more after manufacture.2 ASTM D 2801 has been replaced by ASTM D 4400.REQUIREMENTSCHARACTERISTICS1Min. % Max. % ASTM FED-STD-141 TABLE 2PROPERTIESINGREDIENT STANDARDSSSPC-Paint 23November 1, 1982Editorial Revisions November 1, 200472refl ectance.
39、At the end of 24 hours, examine the enameled portion of the two panels for a difference in gloss. Differences in enamel hold-out will indicate unsatisfactory coalescence.5.12 FILM IRREGULARITY: Apply one coat of the latex primer by the drawdown method to a 4 x 8 inch (10 x 20 cm) cold-rolled steel p
40、anel to produce a dry fi lm thickness of 4.0 0.5 mils (102 13 micrometers). Allow to dry at 74 to 80F (23 to 27C) and 50% 5% relative humidity for 24 hours. Examine the fi lm for mud-cracking, alligatoring, or other fi lm irregularity; there shall be none.5.13 SALT SPRAY AND BLISTER RESISTANCE: Prep
41、are quadruplicate 4 x 8 inch (10 x 20 cm) by 24 gauge panels according to ASTM D 609, Type 2 steel. Spray-apply two coats (allow 48 hours drying time between coats) to produce a total dry fi lm thickness of 4.0 to 4.5 mils (102 to 114 micrometers). Allow to dry at 74 to 80F (23 to 27C) and at 50% 5%
42、 relative humidity for 14 days. Coat and seal all edges and the backside of each panel with a suitable protective coating.Scribe a 3 inch (8 cm) “X” through the middle portion of the painted panels so as to expose the underlying metal before testing. The conditions of making the scratch shall be as
43、described in ASTM D 1654.Expose duplicate panels in the salt fog box at an angle of 15 degrees from the vertical for 300 hours according to ASTM B 117. Examine the panels at 72-hour intervals for rusting and blistering. At the end of 300 hours, immediately examine for rusting and blistering. The rus
44、ting shall not exceed “8A” according to SSPC-VIS 2 or ASTM D 610, and the blistering shall not exceed “8F” according to ASTM D 714. After exam-ining the panels for blistering, immediately remove the paint fi lm with a suitable organic solvent. If scraping of the paint fi lm is necessary to remove it
45、, do not use a metal spatula or razor blade; use a piece of soft wood. Examine the steel substrate. The rusting shall not exceed “9” as judged by SSPC-VIS 2 or ASTM D 610. The rust creep, as judged by the bare panel, shall not exceed 1/8 inch (3 mm) from the center of the scribe.Expose the other pai
46、r of duplicate panels on a Cleveland Condensing Cabinet according to ASTM D 2247 for 300 hours at 100F (38C). Examine the panels at 72-hour intervals for rusting and blistering. At the end of 300 hours, immediately examine for rusting and blistering. The rusting shall no exceed “8“ according to SSPC
47、-VIS 2 or ASTM D 610 and the blistering shall not exceed “8F” according to ASTM D 714. After exam-ining the panels for blistering, immediately remove the paint fi lm with a suitable organic solvent. If scraping of the paint fi lm is necessary to remove it, do not use a metal spatula or razor blade;
48、use a piece of soft wood. Examine the steel substrate. The rusting shall not exceed “9” as judged by SSPC-VIS 2 or ASTM D 610. The rust creep, as judged by the bare panel, shall not exceed 1/8 inch ( 3 mm) from the center of the scribe.5.14 FLASH RUST RESISTANCE TEST: Apply one coat of the primer at
49、 1.5 mils (38 micrometers) dry fi lm thickness to a panel prepared according to ASTM D 609, Type 2 steel. Allow the panel to dry in a horizontal position for 48 hours at 74 to 80F (23 to 27C) and 50% 5% relative humidity. At the end of the drying period, examine for fl ash rusting or rust bleeding. The primer shall show no rust bleed and the steel shall not show any corrosion when the latex fi lm is removed.5.15 WET
