Interview Questions for Ceramic Screen Printing

Ceramic screen printing is a stencil printing technique where ink is forced through a mesh screen onto a ceramic substrate. Think of it like using a finely woven sieve to apply a design. The process involves creating a stencil on the screen, aligning it with the ceramic piece, and then pressing ink through the open areas of the stencil to create your image or design. This process is repeated for each color in a multi-color design.

The steps typically include:

• Screen Preparation: Stretching and preparing the mesh screen, coating it with emulsion to create a stencil.
• Image Exposure: Exposing the coated screen to a light source (UV or other) through a film positive of the design. This hardens the emulsion in the unexposed areas, creating the stencil.
• Screen Development: Washing away the unexposed, soft emulsion, revealing the open areas of the stencil.
• Ink Application: Using a squeegee to push ink across the screen and onto the ceramic substrate.
• Drying and Firing: Allowing the ink to dry and then firing the ceramic piece in a kiln to fuse the ink to the substrate, making the design permanent.

For example, imagine printing a custom design on a ceramic mug. Each color (the handle, the image, the text) would require its own screen and printing step, carefully aligned to create the final product.

Ceramic inks are categorized based on their chemical composition and firing requirements. The choice of ink depends heavily on the desired aesthetic effect and the type of ceramic substrate. Some common types include:

• Low-fire inks: These require lower firing temperatures (around 1000°C), making them suitable for certain types of clay and less energy-intensive. They are often used for decals and detailed work where high-temperature stability isn’t crucial.
• High-fire inks: These are designed to withstand much higher firing temperatures (upwards of 1200°C) and offer greater durability and color vibrancy. They’re essential for applications where the ceramic item will experience high heat or frequent washing, such as dinnerware.
• Underglaze inks: Applied under a glaze layer, these inks provide a subtle, matte finish, offering a softer, less glossy look.
• Overglaze inks: Applied over a glaze layer, these inks create a glossy, vibrant finish. They’re often used for striking color effects and bold designs.
• Metallic inks: These provide a lustrous, metallic sheen. They can be low-fire or high-fire, depending on their composition and intended use. Gold, silver, and platinum are common examples.

For instance, a high-fire ink is necessary for creating a durable design on a ceramic tile that will be exposed to the elements, while a low-fire ink might be sufficient for a decorative plate that won’t experience harsh conditions.

Plastisol and water-based inks represent two distinct approaches in ceramic screen printing, each with its own advantages and disadvantages.

• Plastisol inks: These are PVC-based inks that require a curing process at high temperatures after printing. They offer excellent opacity, vibrant colors, and a thick, durable finish. They tend to be easier to clean up as they remain sticky before curing, allowing for easier removal of excess ink from the screen. However, they require specialized equipment for curing and have environmental concerns due to their PVC base.
• Water-based inks: As the name suggests, these inks are water-based and less harmful to the environment. They’re generally easier to handle and require simpler cleanup. However, they might not offer the same vibrancy or opacity as plastisol inks, and may require multiple layers to achieve the desired color intensity. They are typically cured via a drying and lower temperature firing.

Choosing between them often depends on budget, environmental concerns, and the desired final aesthetic. For high-volume production with vibrant, durable prints, plastisol might be preferred. For smaller-scale projects or environmentally conscious production, water-based inks might be a better choice. The type of ceramic substrate can also influence the decision, as some substrates may better accept water-based inks while others may require the durability of a plastisol.

Mesh count and tension are critical factors influencing the quality and precision of the printed design. The mesh count refers to the number of threads per inch (or cm) in the screen. Higher mesh counts (e.g., 156 threads/inch) result in finer detail and sharper lines, but require more pressure and thinner ink layers. Lower mesh counts (e.g., 43 threads/inch) are better suited for larger, less detailed prints and allow for thicker ink layers. Think of a fine sieve for delicate work versus a coarser sieve for large particles.

Tension refers to how tightly the mesh is stretched on the screen frame. Proper tension ensures even ink distribution and prevents the screen from sagging, which could lead to blurry prints or inconsistencies. Too little tension can result in a distorted image, while excessive tension might damage the mesh. A properly tensioned screen is essential for consistent results.

Determining the appropriate mesh count and tension involves considering the design complexity, the ink viscosity, and the desired print quality. Experience and testing are crucial to optimize these parameters for specific projects. For instance, detailed line work needs a higher mesh count and appropriate tension. For a large area fill, lower mesh count may be suitable. Tension is generally checked using a tension meter to ensure uniform tautness across the screen.

Emulsion selection significantly impacts the screen’s performance and the quality of the final print. Emulsion acts as the light-sensitive layer that forms the stencil on the screen. The type of emulsion chosen will affect the stencil’s durability, sensitivity to light, and ease of use. There are several factors to consider:

• Sensitivity to light: High-sensitivity emulsions require shorter exposure times, saving time and energy. Low-sensitivity emulsions need longer exposure times, but often offer improved durability.
• Hardness and toughness: A tough emulsion is less prone to damage during the printing process and can withstand more prints. A softer emulsion is easier to wash out during development but might not withstand many passes.
• Compatibility with inks and cleaning solutions: The chosen emulsion should be compatible with the inks and cleaning agents used, ensuring it won’t dissolve during the printing process or make cleaning difficult.

Choosing the wrong emulsion could lead to issues such as pinholes (tiny holes in the stencil), incomplete stencil development, or short screen lifespan. For example, a high-sensitivity emulsion is ideal for intricate, fine-line designs where precise detail is critical and multiple screens might not be needed. A more durable emulsion is preferred when high print volumes are anticipated to extend the screen’s usability.

The exposure and development stages are pivotal in creating a precise stencil on the screen. These steps translate the digital design into a physical mask that will define which areas are printed.

Exposure: This involves placing a film positive (a transparent film with the reversed design) onto the emulsion-coated screen and exposing it to a UV light source. This hardens the emulsion in the areas not covered by the film positive. The exposure time is crucial; insufficient exposure will lead to a weak stencil, while overexposure might harden the emulsion unevenly. Exposure times vary depending on the emulsion’s sensitivity and the UV light source’s intensity. This is calibrated based on tests and manufacturer’s recommendations.

Development: After exposure, the screen is washed with a water-based solution to remove the unexposed, soft emulsion. This reveals the open areas of the stencil that will allow ink to pass through during printing. This process requires careful attention to detail to ensure that the stencil is clean and free of any residual unexposed emulsion. The washing process might be done by hand or using a pressure washer for quicker and more efficient rinsing. The goal is to expose only the desired areas, and this process is perfected through repeated experimentation and refinement.

Proper exposure and development are paramount for crisp, sharp prints. Incorrect exposure can lead to blurry images, while inadequate development can result in clogged stencils or loss of detail.

Achieving accurate registration in multi-color ceramic screen printing is essential for creating designs with precise color alignment. Misaligned prints can lead to blurred images or entirely ruin the artwork. There are several strategies to ensure accurate registration:

• Micron-accurate registration system: This is vital for multi-color print jobs where consistent alignment is critical. These systems use precise mechanical guides and clamps to maintain the screen’s position during each printing pass. The system accurately adjusts for minute misalignments, helping in the achievement of perfect color registration across multiple screens.
• Multiple registration marks: Creating registration marks (small, precise marks) on the screens and the ceramic substrate is vital. These marks act as guides for aligning the screens during successive printing steps. A minimum of three registration marks are recommended—more for complex designs. For example, a simple ‘+’ mark is usually sufficient for smaller designs. They are usually placed in easily accessible areas on the ceramic piece. The position of the screen is adjusted using these marks during the print process.
• Precise screen clamping: Ensure the screens are securely clamped to the printing frame to prevent movement during the printing process.
• Careful setup and planning: Thorough planning and precise setup before beginning the printing process are crucial. This includes verifying alignment using the registration marks and ensuring adequate lighting for optimal visibility.

Maintaining accurate registration requires practice and attention to detail. Testing and making minor adjustments before starting a large production run are recommended to prevent costly errors.

Ceramic screen printing, while rewarding, presents several common challenges. These often stem from the interplay of ink properties, substrate characteristics, and the printing process itself. Think of it like baking a cake – if you don’t get the ingredients or temperature right, the result won’t be ideal.

• Ink-related issues: Poor ink viscosity (too thick or thin), improper mixing, or using an ink incompatible with the substrate can lead to inconsistent print quality. Imagine trying to spread frosting that’s too thick or too runny – the result will be uneven.
• Screen issues: A damaged screen, clogged mesh, or incorrect tension can cause blurry prints, pinholes, or incomplete image transfer. Think of the screen as a stencil – if it’s damaged, your stencil will be compromised.
• Substrate problems: An improperly prepared substrate (e.g., insufficient cleaning, uneven surface) can result in poor ink adhesion and uneven printing. It’s like trying to paint on a dirty wall; the paint won’t adhere properly.
• Environmental factors: Humidity and temperature fluctuations can significantly impact ink drying and curing, potentially leading to defects. Similar to how humidity affects the drying time of paint.
• Firing issues: Incorrect firing temperature or cycle can cause cracking, crazing (fine cracks on the glaze surface), or color changes in the fired prints. This is analogous to baking a cake at the wrong temperature; it will either burn or remain uncooked.

Troubleshooting ceramic screen printing defects requires a systematic approach. We need to examine each stage of the process to identify the root cause.

• Pinholes: These tiny holes are often caused by air bubbles trapped in the ink, improper screen preparation (e.g., clogged mesh), or too-thin ink. Solutions include degassing the ink, ensuring proper screen cleaning and stretching, and adjusting the ink viscosity.
• Smearing: Smearing happens when the ink is too wet, the squeegee pressure is too low, or the substrate is too absorbent. Adjusting the squeegee pressure, using a suitable ink for the substrate, or adding a suitable undercoat can help resolve smearing.
• Cracking: Cracking in the fired print often indicates either the ink is not compatible with the substrate, the firing temperature is too high, or the firing cycle is too rapid. Checking the ink manufacturer’s specifications, using a slower firing cycle, and controlling the firing temperature is important.

In all cases, meticulously documenting the process parameters – ink type, viscosity, squeegee pressure, firing schedule – helps in identifying patterns and preventing future defects. It’s like keeping a detailed baking recipe; you know what went wrong and can adjust it next time.

Proper drying and curing are paramount in ceramic screen printing, impacting the final print’s durability, adhesion, and aesthetic quality. Think of it as setting the foundation for a strong and beautiful building.

Drying removes the solvent from the ink, allowing the ceramic particles to bond properly. Inadequate drying can lead to cracking, peeling, or smearing during handling or firing. This initial stage ensures the print is stable before it enters the intense heat of the kiln.

Curing, the high-temperature process in the kiln, fuses the ink to the substrate. Incorrect curing causes the ink to not adhere, affects color, or leads to defects. It is crucial for achieving the desired color, gloss, and durability of the print. This final stage transforms the print into a permanent part of the ceramic piece.

Controlling both drying and curing conditions is crucial; this includes maintaining consistent humidity and temperature throughout the process.

Several kiln types are used for firing ceramic screen-printed pieces, each with its own strengths and limitations. The choice depends on factors like budget, production volume, and desired firing profile.

• Electric Kilns: Precise temperature control, energy efficiency, and suitability for smaller studios. They are user-friendly and safer for smaller-scale applications.
• Gas Kilns: Faster firing rates, higher temperatures achievable, and suitable for large-scale production runs. Requires proper ventilation and safety protocols.
• Rapid-fire Kilns: Very fast firing cycles, ideal for quick turnaround times, but requiring specific ink formulations designed for rapid firing to prevent cracking.

Choosing the correct kiln depends entirely on your budget and production needs; a small studio will likely opt for an electric kiln, while a larger manufacturer would likely invest in a gas kiln or potentially a rapid-fire kiln for high throughput.

Firing temperatures and cycles vary significantly depending on the type of ceramic ink used. Always refer to the manufacturer’s guidelines; they are not interchangeable! Think of it like following a recipe carefully – each ingredient requires specific cooking times and temperatures.

Generally, low-fire inks require lower temperatures (around 700-1000°C), while high-fire inks necessitate higher temperatures (1100-1300°C or even higher). The firing cycle (heating, soaking, cooling rates) is also crucial and affects the final color and durability. A too-rapid heating or cooling can cause thermal shock and cracking.

For instance, a low-fire decal may only require a brief firing to fuse the decal onto the ceramic; high-fire inks need significantly longer firing cycles to allow proper vitrification and development of the ink.

Incorrect temperature and cycle parameters can seriously impact the final product – everything from dull colors to cracking and peeling is possible.

Ensuring durable and long-lasting ceramic prints requires attention to detail at every stage of the process. It’s a holistic approach that ensures your print lasts a lifetime.

• Proper substrate preparation: A clean, smooth surface ensures optimal ink adhesion. Think of it as a well-prepared canvas for your artwork.
• Choosing appropriate inks: Selecting inks specifically designed for the substrate and intended use is critical. Using the wrong ink will severely limit durability.
• Precise screen printing technique: Accurate ink application prevents defects and enhances longevity. A good print is half the battle won.
• Optimal drying and curing: Following the manufacturer’s recommended drying and curing parameters ensures proper bonding between the ink and the substrate.
• Post-firing handling: Protecting the fired prints from damage during handling and storage is essential. Careful handling prevents scratching and chipping.

Durability should be top of mind from the selection of the inks and substrate right through to final packaging and handling; this ensures the print will last through the years.

Pre-press preparation is the foundation upon which a successful ceramic screen print is built. It’s like preparing your canvas before starting a painting; if the canvas is not prepared properly, the result will not be as good.

This crucial step involves several key aspects:

• Artwork preparation: Creating high-resolution artwork that’s properly sized and formatted for screen printing is paramount. A blurry image will result in a blurry print.
• Film production: Generating high-quality films from the artwork ensures accurate image reproduction onto the screen. This involves selecting the proper resolution and film material.
• Screen preparation: This includes coating the screen with emulsion, exposing it to light to create the image, and washing away the unexposed emulsion to create the stencil. This is a critical step, and a damaged screen will create a poor print.
• Ink preparation: Mixing inks to the correct viscosity, degassing to remove air bubbles, and ensuring proper color consistency are crucial for achieving consistent print results. Incorrect ink preparation leads to defects.
• Substrate preparation: Cleaning and preparing the ceramic substrate (bisque) ensures the ink adheres properly. Any residual material may prevent ink from adhering or create unsightly marks.

Thorough pre-press preparation prevents costly mistakes and ensures the efficiency of the printing process, resulting in consistently high-quality prints.

My experience encompasses both manual and automatic ceramic screen printing techniques. Manual screen printing, while slower, offers greater control and is ideal for smaller runs or intricate designs. I’ve worked extensively with hand-held squeegees, carefully controlling pressure and speed for precise ink deposition. This is particularly useful for achieving unique effects or working with delicate substrates. Automatic screen printing, on the other hand, utilizes machinery to automate the process, significantly increasing production speed and efficiency. I’m proficient in operating automatic presses, including setting up screens, adjusting print parameters like squeegee pressure and speed, and maintaining consistent print quality across large production runs. I’ve used both carousel and flatbed automatic presses, adapting my techniques to the specific machine’s capabilities.

For example, when working on a limited-edition ceramic tile collection with a complex design, the precision of manual screen printing was essential to capture the intricate details. In contrast, producing hundreds of identical mugs for a large corporate order required the speed and efficiency of an automatic press.

Maintaining and cleaning screen printing equipment is crucial for consistent print quality and the longevity of the equipment. My cleaning routine begins immediately after printing. This involves removing excess ink from the screens using a suitable solvent, specific to the ink type used (e.g., water-based inks require water and detergent, while solvent-based inks need a designated solvent). Screens are then thoroughly rinsed and stored properly to prevent them from drying out and damaging the emulsion. The printing press itself is cleaned regularly, focusing on areas where ink build-up is common, like the squeegee blade and the print head. I regularly inspect and lubricate moving parts according to the manufacturer’s instructions to ensure smooth operation and prevent mechanical failures. For example, I meticulously clean the squeegee blade after each print run to avoid ink build-up which could affect print consistency and lead to smearing. Preventing clogs is critical in maintaining the efficiency of the press and reducing downtime.

Safety is paramount in ceramic screen printing. I always wear appropriate personal protective equipment (PPE), including gloves to protect against skin irritation from inks and solvents, eye protection to shield against splashes, and a respirator to prevent inhalation of ink fumes or dust. The workspace is well-ventilated to minimize the risk of inhaling hazardous materials. I handle solvents and other chemicals with care, following the manufacturer’s safety data sheets (SDS) and storing them in properly labeled containers. Furthermore, I am trained to handle any potential emergencies like ink spills or equipment malfunctions. Regular safety training and adherence to strict safety protocols are essential parts of my workflow. For instance, during solvent cleaning, I ensure the area is well-ventilated and wear appropriate gloves and eye protection to prevent accidental exposure.

Consistent color matching is crucial for maintaining product quality and brand consistency. I use color charts and spectrophotometers to accurately measure and match colors. Before starting a large-scale print run, I create test prints to fine-tune the ink mixture and ensure it meets the required color specifications. I also account for variations in substrate absorption, as different ceramic types may affect the final color appearance. For instance, porcelain might absorb ink differently than stoneware, requiring slight adjustments to the ink formula for a consistent result. Maintaining detailed records of ink mixes, including the ratios of different pigments and additives, is crucial for ensuring future color reproducibility. This detailed documentation helps in achieving consistent color matching across different production batches.

My experience encompasses a wide range of ceramic substrates, including porcelain, stoneware, earthenware, and bone china. Each material presents unique challenges and requires specific adjustments to the screen printing process. Porcelain, for example, is known for its smooth, non-porous surface, which can require a different type of ink and a specific screen mesh count for optimal results. Stoneware, being more porous, may require a higher viscosity ink to avoid excessive absorption. Earthenware has its own absorptive qualities, and bone china requires a specialized ink to avoid damaging its delicate structure. I adapt my screen printing techniques and ink choices based on the substrate’s properties, ensuring consistent and high-quality results across different materials. Knowledge of the bisque firing temperature is critical to the ink selection to ensure the color is not damaged or altered during the firing process.

Managing ink viscosity is essential for achieving consistent print quality. Ink that is too thick will result in poor detail and uneven coverage, while ink that is too thin can lead to bleeding and loss of definition. I use viscometers to measure and control the viscosity of the inks, adjusting it as needed by adding appropriate thinners or thickeners. The specific method of viscosity control depends on the type of ink used and the printing requirements. For instance, water-based inks might require the addition of a water-based thinner, whereas solvent-based inks may need specialized thinners for proper viscosity adjustments. Maintaining consistent ink viscosity is essential for maintaining uniform print quality across all prints and ensuring consistent color.

Color separation techniques are critical for reproducing complex, multi-colored designs in ceramic screen printing. I utilize software like Adobe Illustrator or Photoshop to create color separations, breaking down a full-color image into individual color channels (typically CMYK or spot colors). Each color channel is then used to create a separate screen, which is printed onto the substrate in the correct sequence. Accurate color separation is crucial to ensuring the final printed image faithfully reproduces the original design. The accuracy of color separation also dictates the final print quality, which can be affected by overlapping colors and potentially the absorption of the inks into the substrates. Experience and expertise are needed to ensure that the color separations are accurate and appropriate for the chosen inks and firing temperature. I’ve successfully used this technique for a number of projects that require intricate and colorful designs. This method allows for precision and control over each individual color layer, ensuring a vibrant and high-fidelity final product.

Halftone screens are crucial in ceramic screen printing for reproducing images with continuous tones, like photographs, as opposed to just solid colors. They achieve this by using dots of varying sizes to create the illusion of shading. A finer halftone screen (measured in lines per inch, or LPI) will result in a smoother, more detailed image, while a coarser screen will produce a more pixelated or grainy look. My experience includes working with screens ranging from 55 LPI for bold, graphic designs to 150 LPI or higher for very fine detail, depending on the desired aesthetic and the quality of the artwork. The choice of LPI greatly impacts print quality: too low, and the image lacks detail; too high, and the printed image may look muddy or lose sharpness due to limitations in the ink and printing process. For instance, I once worked on a project requiring a high-resolution image of a delicate floral pattern. Using a 133 LPI screen was essential to capturing the subtle variations in the petals and leaves. A lower LPI screen would have resulted in a far less appealing, coarser print.

Maintaining a clean and efficient workspace is paramount in ceramic screen printing for both safety and quality. Waste management involves proper disposal of spent inks, solvents, and cleaning materials, adhering strictly to all local environmental regulations. We utilize designated containers for each type of waste, color-coded for easy identification. Screen cleaning is a crucial aspect, involving a multi-step process using appropriate solvents and cleaning agents to remove residual ink thoroughly and extend the screen’s lifespan. We avoid cross-contamination by utilizing separate cleaning solutions and brushes for different inks. Furthermore, regular sweeping and mopping ensure a clean workspace, reducing the risk of accidents and improving overall efficiency. Our team adheres to a strict cleaning schedule at the end of each day, leaving the area organized and ready for the next project. Think of it like a painter cleaning brushes after each session – it’s crucial for the longevity of your tools and the quality of your work.

Quality control is an integral part of every ceramic screen printing project. Our procedures begin with a meticulous review of the artwork and halftone screen selection to ensure they match the client’s expectations. Before printing, we conduct test prints on scrap ceramic pieces to adjust ink consistency, screen tension, and pressure. During the printing process, regular inspection of each printed piece is crucial to detect any defects, including pinholes, misregistrations, or uneven ink deposits. We use calibrated measuring tools to ensure precise alignment and color consistency. We maintain detailed records of each batch, including ink formulations and printing parameters. If any defects are found, the process is halted, the issue is diagnosed, and corrections are made before resuming. Post-printing inspection involves examining the fired pieces for any imperfections and ensuring the final product meets our stringent quality standards. This rigorous approach ensures client satisfaction and maintains our reputation for high-quality work. Failing to do this could mean delivering sub-standard products and wasting time and materials rectifying them later.

Squeegees are essential tools in screen printing, impacting ink transfer and print quality. The choice of squeegee depends on the ink viscosity and desired print effect. We use a variety of squeegees with different blade materials (rubber, polyurethane) and durometers (hardness). For instance, a harder squeegee with a sharper edge is better suited for high-viscosity inks and fine-detail printing, producing crisp lines and consistent ink coverage. Softer squeegees are preferred for lower-viscosity inks to avoid smearing and creating a smoother, softer print. The squeegee angle and pressure are also important factors; a steeper angle with more pressure yields a thicker ink deposit while a shallower angle with less pressure leads to a thinner, more delicate print. I’ve found that polyurethane squeegees are versatile and long-lasting, especially for ceramic inks which can be abrasive. Selecting the right squeegee is like choosing the right brush for painting – the wrong tool can significantly impact the final result.

Determining the appropriate pressure and speed during printing is a critical skill acquired through experience and experimentation. Excessive pressure can cause ink to seep under the stencil, resulting in blurry images or bleeding. Insufficient pressure, on the other hand, leads to uneven ink deposits and incomplete image transfer. Similarly, the speed of the squeegee affects ink distribution. Too fast, and the ink might not deposit evenly; too slow, and the ink could dry prematurely, leading to inconsistencies. The optimal pressure and speed depend on several factors including ink viscosity, screen mesh count, and the desired ink thickness. We often begin with trial prints, adjusting the pressure and speed until we achieve the desired result. Think of it like controlling the flow of water from a hose – too much pressure, and it splashes; too little, and the flow is weak. Finding the right balance guarantees a consistent, high-quality print each time.

Digital screen printing techniques have revolutionized the industry by offering precise control and automation. While traditional screen printing relies on hand-cut stencils, digital methods utilize computer-generated images to create screens directly using direct-to-screen or inkjet printing techniques. This allows for high-resolution images, complex designs, and faster turnaround times. My experience with digital techniques includes using direct-to-garment (DTG) printers and utilizing digital imaging software to create halftone screens. These technologies allow for greater precision and efficiency, particularly when dealing with high-volume production or intricate designs that are difficult or time-consuming to create manually. One recent project involved a client requiring a highly detailed, multi-colored design on a large batch of ceramic tiles. The speed and precision of digital screen printing made this project feasible and delivered superior results compared to traditional techniques.

One memorable challenge involved a client’s intricate design which was producing inconsistent results – specifically, the fine lines were blurry and the colors were not blending smoothly in certain areas. Initially, we suspected the screen mesh count was too low for the detail level, but changing the screen didn’t fully resolve the problem. After carefully reviewing the process, we identified the culprit: the ink was too thick and the squeegee was too hard, causing the ink to deposit unevenly and bleed into the fine lines. We systematically addressed the issue by: 1) thinning the ink using the appropriate solvent. 2) switching to a softer squeegee with a slightly more rounded edge. 3) adjusting the pressure and squeegee angle for a more consistent ink lay down. Finally, we conducted thorough test prints until we achieved a high-quality print conforming to the client’s specifications. It reinforced the importance of methodical troubleshooting and the collaborative nature of problem-solving in our field.