Numbering and Direct Part Marking Using Data Matrix Section 2.8: Numbering and Direct Part Marking Using Data Matrix (ECC 200) Table of Contents 2.8.1 Introduction...3 2.8.1.1 Criteria for Direct Part Marking...3 2.8.1.2 Guidance for Symbology Selection with Direct Part Marking Process..3 2.8.2 References...4 2.8.3 Definitions...4 2.8.3.1 Terms and Definitions...4 2.8.3.2 Abbreviations...5 2.8.4 Data Requirements...5 2.8.4.1 Mandatory Data Elements...5 2.8.4.2 Optional Data Elements...5 2.8.5 Marking Methods...6 2.8.5.1 Intrusive (Subtractive Methods)...7 2.8.5.2 Non-Intrusive (Additive Methods)...7 2.8.5.3 Host (Substrate) Surface...7 2.8.5.4 Substrate Surface Thickness...8 2.8.6 Symbol Metrics...9 2.8.6.1 X and Y Dimensions...9 2.8.6.2 Human Readable Interpretation...9 2.8.6.2.1 Location...9 2.8.6.2.2 Font...9 January 2006 Version 7.0 Section 2.8 - Page 1
Numbering and Direct Part Marking Using Data Matrix 2.8.6.2.3 Format...9 2.8.6.3 Symbol Quality...10 2.8.6.4 Location...10 2.8.7 Scanning Requirements...10 January 2006 Version 7.0 Section 2.8 - Page 2
2.8.1 Introduction These guidelines provide the generic requirements for applying Data Matrix symbols to items using direct part marking (DPM). Direct part marking refers to the process of marking a symbol on an item using an intrusive or non-intrusive method. Guidelines for specific application guidelines that may have additional requirements are listed in the reference section. In lieu of specific industrial or retail applications, these guidelines will provide the minimum requirements. The use of Data Matrix in direct part marking applications is endorsed by GS1 for those applications that require permanent marking for cradle-to-grave history of the part s lifecycle. 2.8.1.1 Criteria for Direct Part Marking Traceability at the component level is required to ensure product integrity. The component identification number is required to be tracked through the manufacturing process and throughout the lifecycle of the product. The component or product is in harsh operational and overhaul environments. Adherent materials (e. g., labels) are prohibited on the component or product. The area allotted for the bar code symbol is limited and poses a problem for other methods. Permanent marking is required. 2.8.1.2 Guidance for Symbology Selection with Direct Part Marking Process Use Data Matrix if: The use of Data Matrix is allowed in the application specification. The marking method will not produce an acceptable linear symbol but will produce an acceptable Data Matrix, e.g., dot peen marking and high-speed ink jet. A GS1 Identification key plus attribute element string are to be encoded Data Matrix is the only symbology that will fit on the item at the application specified X- dimension. Low contrast signal is expected from the application. The use of 2D (two-dimensional) array scanners and/or vision systems are specified exclusively for the application and can read Data Matrix. January 2006 Version 7.0 Section 2.8 - Page 3
2.8.2 References The standards listed below are referenced in these guidelines. The relevant provisions contained in the referenced specifications constitute provisions of these guidelines. ISO/IEC 16022 Information Technology- International Symbology Specification Data Matrix ISO/IEC 15415 Information technology Automatic identification and data capture techniques Bar code print quality test specification 2D symbols ISO/IEC 15416 Information technology Automatic identification and data capture techniques Bar code print quality test specification linear symbols ISO 1073-2 Alphanumeric character sets for optical recognition Part 2: Character set OCR-B Shapes and dimensions of the printed image 2.8.3 Definitions 2.8.3.1 Terms and Definitions The terms and definitions provided here and those from the glossary (see Section 8) apply to these guidelines: Dot Cell Intrusive marking Non-Intrusive marking Peen A localized region with a reflectance, which differs from that of the surrounding surface. The area within a Data Matrix symbol where a mark may be placed to indicate a binary value Marking by removing or altering substrate material Does not alter the substrate material, and usually adds to that surface. Hemispherical or wedged shaped instrument that is mechanically driven to produce a dot on the surface January 2006 Version 7.0 Section 2.8 - Page 4
2.8.3.2 Abbreviations 2D DPM GALE LISI LIVD Two-dimensional Direct Part Marking Gas Assisted Laser Etching Laser Inductive Surface Improvement Laser Induced Vapor Deposition 2.8.4 Data Requirements In general, all participants in the supply chain shall be able to read and process all of variants of symbols based on ECC 200 that include mandatory and agreed to optional data elements. 2.8.4.1 Mandatory Data Elements Data Matrix must minimally encode a Function Code One (FNC1) and a GS1 Identification Key with its associated Application Identifier (AI). Some common examples for GS1 Identification keys that can be directly marked with Data Matrix include: (01) GTIN (Global Trade Item Number) (8003) GRAI (Global Returnable Asset Identifier (8004) GIAI (Global Individual Asset Identifier) 2.8.4.2 Optional Data Elements Using Application Identifiers, additional elements that refer to the particular key can be encoded using similar rules to concatenate AI s as documented in section 4.0. Refer to Section 7 of these for a complete description of Element Strings. For Example: Healthcare: Using AI s (17) and (10) with GTIN Parts Identification: Using AI (21) with GTIN January 2006 Version 7.0 Section 2.8 - Page 5
Figure 2.8.4.2-1 Example of Data Matrix Symbol Encoded with GTIN and AI s (17) and (10) per Section 2.7 Figure 2.8.4.2-2 Example of Data Matrix Symbol Encoded with GTIN and Serial Number AI (21) 2.8.5 Marking Methods It is important to analyse the selected method of marking in relation to several considerations: Finishes that cause an excess of shadowing or glare Surfaces that do not provide sufficient contrast - less than 20% difference in surface reflectance. Safety critical parts that can not be marked with intrusive methods Marking method must comply with the users requirements Location of the symbol should not be: o o o In direct air/water etc. streams On sealing surfaces On surfaces subject to wear or exposure to heavy contact January 2006 Version 7.0 Section 2.8 - Page 6
2.8.5.1 Intrusive (Subtractive Methods) Intrusive marking refers to methods that remove or alter the material of the host. Abrasive blast Dot peen Electro-chemical marking, colouring or etching Engraving/milling Fabric embroidery/weaving Direct laser marking Laser shot peening Laser Inducted Surface Improvement (LISI) Gas Assisted Laser Etch (GALE) Laser Induced Vapor Deposition (LIVD) 2.8.5.2 Non-Intrusive (Additive Methods) Non-Intrusive marking does not affect the host material; it usually involves the addition of material. Cast, forge, mold Inkjet Laser bonding Liquid metal jet Silk screen Stencil 2.8.5.3 Host (Substrate) Surface Direct part marking of Data Matrix should be reserved for surfaces no rougher than 250 micro-inches (millionths of an inch) and for surfaces that are no smoother than 8 micro-inches. Surfaces that fall outside these parameters need to be re-surfaced or marked using an alternative method. Consideration of the surface colour must be taken. A minimum 20% difference in contrast between the host and the symbol is required. January 2006 Version 7.0 Section 2.8 - Page 7
Altering the cell size in relation to the surface roughness should provide adequate contrast on cast surfaces. (Cell size = (0.00006 X Roughness) + 0.0067) (See Table 2.8.5.3-1) Table 2.8.5.3-1 Average Roughness Cell Size Minimum.508 micrometers (20 micro inches).1905mm (.0075 ) 1.524 micrometers (60 micro inches).2286mm (.009 ) 3.048 micrometers (120 micro inches).381mm (.015 ) 5.08 micrometers (200 micro inches).508mm (.020 ) 7.62 micrometers (300 micro inches).635mm (.025 ) 10.668 micrometers (420 Micro inches).762mm (.030 ) 2.8.5.4 Substrate Surface Thickness A minimum host surface thickness is recommended as is a maximum marking depth. Both are outlined in the table below. Table 2.8.5.4-1 Method Min. Thickness Max Marking Depth Dot Peen 1.016 mm (.04 ).102 mm (.004 ) Laser Shot peening.508mm (.020 ).051 mm (.002 ) Laser Bonding.025 mm (.001 ) Surface Mark Abrasive Blast.076 mm (.003 ).008 mm (.0003 ) Electro-Chemical Colouring.508 mm (.02 ).051 mm (.002 ) Laser Etch.762 mm (.03 ).076 mm (.003 ) LISI 1.016 mm (.04 ).102 mm (.004 ) Laser Engraving 1.27 mm (.05 ).127 mm (.005 ) Electro-Chemical Etch 2.54 mm (.100 ).254 mm (.01 ) Micro-Milling 31.75 mm (1.250 ) 3.175 mm (.125 ) January 2006 Version 7.0 Section 2.8 - Page 8
2.8.6 Symbol Metrics 2.8.6.1 X and Y Dimensions Some sources express the height of the 2D cell in terms of a Y dimension. For Data Matrix the cells are considered the same size under optimal print conditions so that X = Y. Consult System Symbol Specification Table 7: 2D Symbols Using Data Matrix, Figure 5.4.2.8-8, for minimum and maximum printing densities and other sizing requirements. Symbol size is determined by the amount of data and the number of rows and columns required to encode the data for the printing density selected. Consult Section 5.6 and Tables 5.6.3.2-1 and 5.6.3.2-2 2.8.6.2 Human Readable Interpretation 2.8.6.2.1 Location If printed, the GTIN shall be printed in human-readable form underneath the symbol. If there is sufficient space to print the human readable interpretation of the optional attribute data, it shall be printed above the symbol in proper sequence of the Application Identifiers. The data shall be printed from top to bottom and left to right. A single Application Identifier with accompanying data shall be displayed on one line and not broken into two lines. 2.8.6.2.2 Font A clearly legible font shall be used for the human-readable digits, e.g. OCR-B as defined in ISO 1073-2. Reasonable alternative type fonts and character sizes are acceptable provided the interpretation is clearly legible. The font should be one that is considered suitable and compatible with other printed materials. When necessary, the font used shall be in accordance with applicable government laws and regulations. 2.8.6.2.3 Format The GTIN shall be printed as a single 14-digit number proceeded by the corresponding Application Identifier (01) enclosed in a parenthesis. (01)04012345678901 AI GTIN The data should be printed with the proceeding AI s enclosed in parenthesis. The order of the data should be the same as encoded in the Data Matrix symbol according to the rules in these GS1General Specifications. The parentheses are not part of the data and are not encoded in the bar code symbol, though the AI s are. (17)050103(10)ABC123 AI Expiry AI Lot January 2006 Version 7.0 Section 2.8 - Page 9
2.8.6.3 Symbol Quality The minimum Symbol quality grade for Data Matrix Symbols shall be specified by the application specification. The measurement of the quality parameters shall be made by a verifier conforming to ISO/IEC 15415. According to this standard an overall grade is shown in the form: Where: Grade/Aperture/Light/Angle "grade" is the overall symbol grade as defined in ISO/IEC 15415 Information technology - Automatic identification and data capture techniques - Bar code symbol print quality test specification - Two-dimensional symbols (e.g., the arithmetic mean to one decimal place of the Scan Reflectance Profile or scan grades). For Data Matrix, the grade number may be followed by an asterisk, *, which indicates that the surroundings of the symbol contain extremes of reflectance that may interfere with reading. For most applications, this should be specified as causing the symbol to fail. "aperture" is the diameter in thousandths of an inch (to the nearest thousandth) of the synthetic aperture defined in ISO/IEC 15415 Information technology - Automatic identification and data capture techniques - Bar code symbol print quality test specification - Two-dimensional symbols. "Light" defines the illumination: a numeric value indicates the peak light wavelength in nanometers (for narrow band illumination); the alphabetic character W indicates that the symbol has been measured with broadband illumination ("white light") the spectral response characteristics of which must imperatively be defined or have their source specification clearly referenced. "Angle" is an additional parameter defining the angle of incidence (relative to the plane of the symbol) of the illumination. It shall be included in the reporting of the overall symbol grade when the angle of incidence is other than 45. Its absence indicates that the angle of incidence is 45. Note: This international standard provides for 30 degrees and 90 degrees illumination in addition to the default 45 degrees. The aperture is normally specified as being 80% of the minimum X-dimension allowed for the application. The printing method must produce the Data Matrix "L" pattern with gaps between the dots less than 25% of the specified aperture. If symbols with greater than the minimum X dimension are allowed by the application, the same absolute maximum gap dimension must be maintained. 2.8.6.4 Location General principles on placement of bar codes are described in Section 6 and apply to the location of Data Matrix Symbols. The majority of uses for these symbols will be on very small items with curved surfaces such as vials, ampoules, and very small bottles. For guidance in locating these symbols on curved surfaces, refer to Section 6.2.3.2. 2.8.7 Scanning Requirements Data Matrix requires a two-dimensional imaging scanner or vision system to read the Data Matrix symbol. Data Matrix is not omni-directionally scannable using a retail style slot scanner. Handheld laser scanners or linear array imagers cannot scan Data Matrix. January 2006 Version 7.0 Section 2.8 - Page 10