Lesson Notes By Weeks and Term v3 - Senior Secondary 2
Image Production
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Image Production
Download the Lessonotes Mobile Nigeria 2025 app for faster lesson access on Android and iPhone.
Subject: Printing Craft Practice
Class: Senior Secondary 2
Term: 1st Term
Week: 5
Theme: Screen Printing
This page supports the lesson note with a companion video and a short classroom-ready summary.
For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.
Move the squeegee on ce on the screen with the right amount of dye/ink. Make reproduction of the design using the screen.
Execute the stroke at a moderate, consistent speed. Too slow, and the ink may dry in the screen; too fast, and the ink may not fully penetrate the substrate or leave voids.
4. Single Pass: Critically, the squeegee should be moved once in a decisive, continuous motion across the entire design area. Multiple passes are generally discouraged as they can blur the image, cause ink bleed, or deposit too much ink.
5. Direction: The stroke should cover the entire image area. A common technique is to pull the squeegee towards the printer, though pushing can also be used.
Step 4: Screen Lift and Inspection
1. Lift Screen: Once the print stroke is complete, lift the screen carefully and smoothly from the substrate. Avoid smudging the fresh print.
2. Inspect Print: Examine the printed image for completeness, sharpness, and consistency. Check for voids, smudges, or uneven ink deposit.
Step 5: Reproduction (Objective 2)
1. Repeat: To make reproductions, remove the printed substrate and replace it with a new, unprinted one on the printing board.
2. Re-ink/Flood (if necessary): If significant time passes or many prints are made, re-flood the screen with ink before the next print stroke. For continuous reproduction, the ink already on the screen from the previous flood/print stroke might suffice for several subsequent prints, requiring only occasional re-flooding.
3. Consistency: Maintain the same squeegee angle, pressure, and speed for each print to ensure all reproductions are identical in quality. 2.
3. Common Challenges and Solutions: Incomplete Print (Voids): Insufficient ink, uneven pressure, squeegee too hard for ink, clogged mesh.
Solution: Add more ink, apply even pressure, use softer squeegee, clean screen.
Smudging/Bleed: Too much ink, inconsistent squeegee angle, substrate moving, screen not lifting cleanly.
Solution: Reduce ink, maintain consistent angle, secure substrate, lift screen smoothly.
Blurred Edges: Lack of "off-contact" (screen touching substrate before print stroke), worn squeegee blade, too much ink.
Solution: Ensure proper off-contact (a small gap between screen and substrate), replace squeegee, use less ink.
Ink Drying in Screen: Slow printing speed, high room temperature, using fast-drying ink without retarder.
Solution: Increase printing speed, work in a cooler environment, use ink retarder. This section details the practical steps and considerations for effectively producing an image using the screen printing method. The focus is on the direct act of printing. 2.
1. Essential Components for Image Production: Prepared Screen: A screen frame with mesh stretched over it, bearing the stencilled design (image areas open, non-image areas blocked).
Squeegee: A tool with a rubber blade used to force ink through the open areas of the screen mesh.
Function: Distributes ink evenly across the screen and pushes it through the mesh onto the substrate.
Types: Different blade profiles (square, rounded, bevelled) exist, but a general-purpose square-edge squeegee is common for most applications.
Hardness (Durometer): Measured in Shore A, typically ranging from 60A (softer for textiles, heavy ink deposit) to 80A (harder for fine details, thinner ink deposit). A medium hardness (70A) is versatile.
Ink/Dye: The colour medium.
Types: Vary based on substrate (e.g., textile inks for fabric, solvent-based inks for plastics, water-based inks for paper/cardboard).
Consistency: Should be smooth and free-flowing but not too thin to bleed or too thick to pass through the mesh easily. Viscosity can be adjusted with retarders or thinners as recommended by the manufacturer.
Quantity: An adequate amount is crucial – enough to cover the top edge of the design, typically a 'bead' of ink spanning the width of the image area. Too little ink leads to incomplete prints; too much leads to mess and wasted material.
Substrate: The material onto which the image is printed (e.g., t-shirt, paper, cardboard, plastic sheet). * Printing Board/Platen: A flat, stable surface on which the substrate is placed. Often, it's covered with an adhesive spray or tape to hold the substrate in place during printing. 2.
2. The Printing Process: Step-by-Step Image Production Step 1: Workspace and Material Preparation
1. Cleanliness: Ensure the printing area, screen, squeegee, and substrate are free of dust, lint, or debris.
2. Substrate Placement: Position the substrate (e.g., a t-shirt or paper) flat on the printing board/platen. If necessary, use a temporary adhesive to prevent movement during printing.
3. Screen Registration (if required): For single-colour prints, align the screen precisely over the substrate to ensure the image is positioned correctly. For multiple colours, registration marks are used to align subsequent screens.
Step 2: Ink Application
1. Ink Loading: Place a bead of screen printing ink along one end of the screen, just above the design area. The ink bead should span the full width of the design.
2. Flooding the Screen (Optional but Recommended): Using the squeegee, perform a light, angled stroke to spread the ink evenly over the entire stencil area. This fills the mesh openings with ink without forcing it onto the substrate, ensuring the screen is "loaded" for the print stroke. This is done with less pressure, typically at a higher angle (e.g., 60-75 degrees).
Step 3: The Print Stroke (Objective 1) This is the core action for image transfer.
1. Squeegee Angle: Hold the squeegee at a consistent angle, typically between 45 to 70 degrees to the screen. A lower angle (closer to horizontal) forces more ink through, suitable for textiles. A steeper angle (closer to vertical) forces less ink through, good for fine details on paper.
2. Pressure: Apply firm, even pressure along the entire length of the squeegee blade. The goal is to force the ink through the open mesh areas while "wiping" the top of the screen clean of excess ink. Inadequate pressure leads to incomplete prints; excessive pressure can distort the screen or push too much ink, leading to bleed.
3. Speed: Execute the stroke at a moderate, consistent speed. Too slow, and the ink may dry in the screen; too fast, and the ink may not fully penetrate the substrate or leave voids.
4. Single Pass: Critically, the squeegee should be moved once in a decisive, continuous motion across the entire design area. Multiple passes are generally discouraged as they can blur the image, cause ink bleed, or deposit too much ink.
5. Direction: The stroke should cover the entire image area. A common technique is to pull the squeegee towards the printer, 3.
1. Teacher Activities: Introduction & Recap: Begin by reviewing the previous lesson on stencil preparation. Briefly introduce the concept of image production as the next crucial step in screen printing, highlighting its commercial relevance.
Material Introduction: Present and explain the function of each printing component: prepared screen, squeegee (demonstrate different holding techniques), various inks suitable for different Nigerian contexts (e.g., fabric ink for 'aso ebi', poster ink for placards).
Detailed Demonstration (Objective 1): Set up a complete screen printing station (screen, printing board, substrate, ink, squeegee). Demonstrate the proper technique for loading ink onto the screen. Perform a slow-motion, step-by-step demonstration of the single, controlled squeegee stroke: Show correct squeegee angle (e.g., 45-60 degrees). Emphasize even pressure application from start to finish. Demonstrate moderate, consistent speed. Highlight the importance of a single pass. Print one clear image, allowing students to observe the result. Demonstration of Reproduction (Objective 2): Demonstrate the process of removing the printed substrate, placing a new one, and repeating the print stroke to create a second, identical reproduction. Emphasize the need for consistency in technique for uniform results.
Guided Practice Setup: Divide students into small groups and assign each group a printing station (or have them share stations sequentially). Ensure each station has a prepared screen (with a simple design), appropriate ink, squeegee, and enough practice substrates (e.g., waste fabric pieces, old newspapers, cardboard).
Circulation and Supervision: Move among groups, observing student attempts. Provide immediate, constructive feedback on squeegee angle, pressure, speed, and overall technique. Address common errors as they occur.
Troubleshooting Session: Facilitate a brief discussion on challenges encountered by students and guide them towards solutions based on the explained key concepts. 3.
2. Student Activities: Active Observation: Students will closely observe the teacher's demonstrations, paying attention to details of squeegee handling, ink application, and stroke execution.
Hands-on Practice (Objective 1): In groups, students will practice holding the squeegee at the correct angle and mimicking the print stroke without ink on a blank screen. Under teacher supervision, students will attempt to perform the single, controlled squeegee stroke using ink, aiming for a clean, complete image. They will experiment with slight variations in pressure and angle to understand their effects.
Reproduction Practice (Objective 2): Students will practice producing multiple identical prints of the same design, focusing on maintaining consistency in their squeegee technique. They will aim to achieve uniform quality across several reproductions.
Peer Feedback: Students will observe and provide constructive feedback to their group members on their printing technique.
Problem-Solving: Students will identify issues with their prints (e.g., incomplete prints, smudges) and, with teacher guidance, try to deduce the cause and implement corrective measures.
Material Handling: Students will participate in setting up their workstations and ensuring responsible handling of inks and equipment. or registration guides) to ensure consistent logo placement.
3. Ink Readiness: Check the ink on the screen. If it appears dry or too low, perform a quick, light 'flood stroke' to spread a fresh, even layer of ink over the stencil area. This ensures the mesh openings are fully charged with ink for the next print.
4. Consistent Squeegee Technique: Replicate the exact squeegee angle, firm and even pressure, and moderate, consistent speed that yielded the first successful print. Every subsequent print stroke must be a single, decisive pass.
5. Repeat and Monitor: Repeat steps 2-4 for each of the remaining 49 cardboard packages. Periodically inspect prints for consistency in quality (sharpness, ink coverage, placement) and adjust technique or ink as needed.
6. Drying: Ensure each printed package is moved to a drying rack or designated area immediately after printing to prevent smudging and allow for proper ink curing before stacking.
Small and Medium-sized Enterprises (SMEs)
Support: Screen printing is a highly accessible and cost-effective method for SMEs across Nigeria to brand their products and services. For instance, a small bakery can screen print its logo onto paper bags for pastries, or a local tailor can print custom designs on fabric for clients. This lesson directly teaches the skill of consistent reproduction, crucial for producing a batch of identical branded items, thereby empowering entrepreneurship and local manufacturing.
Community Development and Awareness: Non-governmental organisations (NGOs) and community groups often use screen-printed materials for awareness campaigns, educational posters, and uniforms for volunteers. Students can apply their knowledge of image production to create informative posters on topics like hygiene, environmental protection (e.g., "Keep Lagos Clean"), or voter education, contributing directly to community well-being and civic engagement.
Cultural Preservation and Expression: Screen printing can be used to reproduce traditional Nigerian patterns, cultural symbols, and artworks on various substrates like fabrics, paper, and wood. This provides a means for local artists and craftspeople to create contemporary pieces that reflect Nigerian heritage, making cultural artifacts more accessible and marketable while also preserving visual traditions. For example, reproducing Yoruba adire patterns or Igbo uli designs through screen printing for modern fashion or home decor.