1、SSPC-Paint 24November 1, 1982Editorial Revisions November 1, 20046-75SSPC: The Society for Protective CoatingsPAINT SPECIFICATION NO. 24Latex Semigloss Exterior Topcoat1. Scope1.1 This specifi cation covers an air drying, ready-mixed, water-borne semigloss latex paint for use on metal surfaces prime
2、d with a primer conforming to SSPC-Paint 23. It is intended for use as a topcoat of a water-borne coating system consisting of two coats of primer and one or two coats of this water-borne topcoat.1.2 This paint is suitable for exposures in Environmental Zones 1A (interior, normally dry) and 1B (exte
3、rior, normally dry), and is intended for brush, spray, or roller application over properly primed steel surfaces and is to be applied in accordance with SSPC-PA 1, “Shop, Field, and Maintenance Painting of Steel.” It is not recommended to expose steel to the weather with less than two coats of water
4、borne coating; therefore, intermediate and topcoats should be applied as soon as possible.2. Description2.1 This paint is based on a latex vehicle produced by emulsion polymerization and appropriate pigments. Details of the composition are given in Table 1.2.2 This paint contains approximately 27% b
5、y 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 215 square feet/U.S. gallon (5.3 square me-ters/liter). Actual spreading rates can be signifi cantly lower.3. Referenced Standards3.1 The latest iss
6、ue, 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 referenced standards and this specifi cation, the requirements of this specifi cation
7、 shall prevail.3.3 SSPC STANDARDS:SSPC Guide 13 Guide for the Identifi cation and Use of Industrial Coating Material in Computerized Product Data-basesPA 1 Shop, Field, and Maintenance Painting of SteelPaint 23 Latex Primer for Steel SurfacesVIS 2 Guide and Reference Photographs for Evaluating the D
8、egree of Rust-ing on Painted Steel Surfaces3.4 ASTM INTERNATIONAL STANDARDS:B 117 Method of Salt Spray (Fog) TestingD 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 Col
9、d-Rolled Steel Panels for Testing Paint, Varnish,Conversion Coatings, and Related Coating ProductsD 610 Test Method for Evaluating Degree of Rusting on Painted Steel SurfacesD 714 Test Method for Evaluating Degree of Blistering of PaintsD 1210 Test Methods for Fineness of Dispersion of Pigment-Vehic
10、le Systems by Hegman-type GageD 1296 Test Method for Odor of Volatile Solvents and DiluentsD 1640 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 (Withdraw
11、n) Elongation of Attached Oranic Coatings with Cylindrical Mandrel Apparatus (Replaced by ASTM D 522)D 1849 Test Method for Package Stability of PaintD 2243 Test Method for Freeze-Thaw Resistance of Water-Borne CoatingsD 2244 Method for Calculation of Color Differences from Instrumentally Measured C
12、olor CoordinatesD 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 Emulsion Paints in the Container to Attack by Micro-organismsD 2801 (Withdrawn) Test Method for Leveling Charac
13、teristics of Paints by Draw-Down MethodSSPC-Paint 24November 1, 1982Editorial Revisions November 1, 20046-76D 3273 Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental ChamberD 3274 Test Method for Evaluating Degree of Surface Disfi gurement of Paint F
14、ilms 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 Related ProductsD 3925 Practice for Sampling Liquid Paints and Related Pigmented CoatingsD 4400 Test Method for Sag Resistance of
15、Paints Using a Multinotch ApplicatorE 11 Specifi cation for Wire-Cloth and Sieves for Testing PurposesE 97 (Withdrawn) Test Method for Directional Reflectance Factor, 45-deg 0-deg, of Opaque Specimens by Broad-Band Fil-ter Refl ectometry (Replaced by ASTM E 1347)E 1347 Test Method for Color and Colo
16、r-Difference Measurement by Tristimulus (Filter) Colo-rimetryG 23 (Withdrawn) Practice for Operating Light-Exposure Apparatus (Carbon-Arc Type) With and Without Water for Exposure of Nonmetallic Materials (Replaced by ASTM G 152 and G 153) G 26 (Withdrawn) Practice for Operating Light-Exposure Appar
17、atus (Xenon-Arc Type) With and Without Water for Exposure of Nonmetallic Materials (Replaced by ASTM G 155.)G 151 Standard Practice for Exposing Non-Metallic Mateials in Accelerated Test Devices that Use Laboratory Light Sources3.6 FEDERAL STANDARDS:TT-E-506 Enamel, Alkyd, Gloss, Tints and White (fo
18、r Interior Use) FED-STD-141 Paint, Varnish, Lacquer and Related Ma-terials: Methods of Inspection, Sampling and Testing Method 2021 (Canceled) Preparation of Glass Panels (Use ASTM D 3891)Method 6141.1 (Canceled) Washability3.7 AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) STANDARD:Z129.1 Hazardous I
19、ndustrial Chemicals Precautionary Labeling4. Composition4.1 The manufacturer is given some latitude in the selec-tion of materials and process of manufacture, provided that the paint meets the requirements of this specifi cation. Materials shall be of the best quality used in good commercial practic
20、e and entirely suitable for the purpose intended under normal conditions 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
21、, and “antifreeze“ in order to produce a paint conforming to this 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
22、.2 through 5.17.5.2 ODOR: Shall be normal for the materials permitted (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 sh
23、all be resistant to attack by microorganisms when tested according to ASTM D 2574.5.5 APPLICATION PROPERTIES: The paint shall be easily applied to a smooth steel vertical surface at 5 mils (127 micrometers) wet fi lm thickness on 320 square feet/gallon (7.9 square meters/liter) by brush, spray, or r
24、oller. Drying shall be done in a well-ventilated room or chamber free from drafts and dust and in diffused light, not in direct sunlight. The temperature of the air shall be between 21 and 28C. The relative humid-ity shall be 50% 5%. There shall be no runs, sags, streaks, fl ashes, laps, pinholes, f
25、i sheyes, or craters. After four hours of drying, apply a second coat in the same manner as the fi rst. There shall be no picking-up or rolling-up of the fi rst coat dur-ing applications. After 24 hours, the fi lm shall be smooth and uniform.5.6 CONDITION IN CONTAINER: The paint as received shall sh
26、ow no evidence of livering, skinning, or hard settling of the pigment. 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 paint shall show a minimum of foaming and be free of grit,
27、seeds, lumps, or livering.SSPC-Paint 24November 1, 1982Editorial Revisions November 1, 20046-775.7 FREEZE-THAW RESISTANCE: The paint shall pass 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 c
28、oarse particles. The maximum allowable increase or decrease in viscosity shall not exceed 10 Kreb units.5.8 WET ADHESION: Prepare 6 x 17 x 1 /4 inch (15 x 43 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 F
29、ederal Specifi cation TT-E-506 drawndown with a suitable applicator obtaining a dry fi lm thickness of 3.0 0.3 mils (76 8 micrometers) and a width of 5-1/2 inch (14 cm). Allow the alkyd enamel to dry in a horizontal position for three days at 74 to 80F (23 to 27C) and 50% 5% relative humidity. Bake
30、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 long axis of the panel 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
31、for 48 hours at 74 to 80F (23 to 27C) and 50% 5% relative humidity.Make a cut (the entire 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 F
32、ED-STD-141, Method 6141) so that the test paint is approximately in the center of the brush stroke and scrub under water with the brush described in ASTM 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 brus
33、h shall travel at a rate of 39 1 cycles (78 2 separate strokes) per minute. There shall be no adhesion failure between the test paint and alkyd undercoat after 800 strokes. The paint may wear through to the alkyd enamel in less than 800 strokes. If this occurs, it shall not be considered as adhesion
34、 failure of the test paint. In the same fashion, this topcoat shall be tested over the manufacturers primer coating complying with SSPC-Paint 23.5.9 PACKAGE STABILITY: Perform the following tests in accordance with ASTM D 1849. When stored for one month at 123 to 127F (51 to 53C), the maximum allowa
35、ble increase or decrease in viscosity shall not exceed 10 Kreb units. After brush-ing, the fi lm shall be free from grains, lumps, or streaks.5.10 FILM IRREGULARITY: Apply one coat of the latex paint by the drawdown method to a 4 x 8 inch (10 cm x 20 cm) cold-rolled steel panel to produce a dry fi l
36、m 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 48 hours. Examine the fi lm for mud-cracking, alligatoring, or other fi lm irregularity; there shall be none.TABLE 1ANALYSISREQUIREMENTS CHARACTERISTICS1Min. % Max. % ASTM FED-STD
37、-141Nonvolatile vehicle 26 Total Solids by Volume 27 1Theoretical as calculated.TABLE 2PROPERTIESREQUIREMENTS CHARACTERISTICSMin. Max. ASTM FED-STD-141Viscosity1shear rate 200 rpmGrams 150 240 D 562 Kreb units 72 88 D 562 Fineness of grind, Hegman units 6.0 D 1210 Drying time, hoursDry to touch 4 D
38、1640 Dry hard 24 D 1640 Sag Resistance, mils 6 D 28012 1 Viscosity 48 hours or more after manufacture.2 ASTM D 2801 has been replaced by ASTM D 4400.SSPC-Paint 24November 1, 1982Editorial Revisions November 1, 20046-785.11 SALT SPRAY AND BLISTER RESISTANCE: Prepare quadruplicate 4 x 8 inch (10 x 20
39、cm) by 24 gage panels according to ASTM D 609, Type 2 steel. Spray-apply one coat of primer SSPC-Paint 23 to a dry fi lm thickness of 2 to 3 mils (51 to 76 micrometers) and allow to dry for 48 hours at 74 to 80F (23 to 27C) at 50% 5% relative humidity. Then spray apply one coat of this paint to a dr
40、y fi lm thickness of 2 to 3 mils (51 to 76 micrometers). Allow the two-coat system to dry at 74 to 80F (23 to 27C) and at 50% 5% 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 port
41、ion of the painted panels so as to expose the underlying metal before testing. The conditions of making the scratch shall be as described in ASTM D 1654.Expose duplicate panels in the salt fog cabinet at an angle of 15 degrees from the vertical for 300 hours according to ASTM B 117. Examine the pane
42、ls at 72-hour intervals for rusting and blistering. At the end of 300 hours, immediately examine for rusting and blistering. The rusting shall not exceed “8” according to SSPC-VIS 2 or ASTM D 610, and the blistering shall not exceed “8” according to ASTM D 714. After examining the panels for blister
43、ing, 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. 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.
44、 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 pair of duplicate panels in 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 blist
45、ering. At the end of 300 hours, immediately examine for rusting and blistering. The rusting shall not exceed “8” according to SSPC-VIS 2 or ASTM D 610, and the blistering shall not exceed “8F” according to ASTM D 714. After examin-ing the panels for blistering, immediately remove the paint fi lm wit
46、h 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. 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 pane
47、l, shall not exceed 1/8 inch (3 mm) from the center of the scribe.5.12 WET ABRASION RESISTANCE: Test the paint as described in ASTM D 2486. Air dry the panel for seven days in an open room kept at 74 to 80F (23 to 27C) and 50% 5% relative humidity before testing. A minimum of 800 strokes or 400 osci
48、llations shall be required to fully remove the paint fi lm on one continuous line across the width of the 1/2 inch (13 mm) shim.5.13 FLEXIBILITY: Flexibility shall be determined in ac-cordance with ASTM D 1737 using a 1/4 inch (6 mm) mandrel and an unscribed panel as described below. Apply a 2 inch
49、(5 cm) wide fi lm of the paint with a fi lm applicator that will give a dry fi lm thickness of 0.9 to 1.1 mils (23 to 28 micrometers) on a smooth fi nish steel panel, prepared in accordance with ASTM D 609, paragraph 5.3 Method C, using the aliphatic naphtha-ethylene glycolmonoethyl ether mixture. The panel shall be new, cold-rolled, rust-free carbon steel No. 20 gage 0.0375 0.0125 inch (0.95 0.31 mm) thickness with a Rock-well 15T max
