永和工芸 Product Lineup

Filling holes is a defect where bolt holes, positioning holes, drainage holes, etc., are blocked by paint. This issue is discovered at the customer site when bolts cannot pass through, parts do not fit into jigs, or water cannot drain. Particularly, if just one drainage hole is blocked, moisture can remain inside, leading to rust reoccurrence or blistering. The causes include excessive film thickness, spray direction, part orientation, jig setup, and paint pooling before drying. Initially, we check the position of functional holes, the extent of blockage, surrounding drips, and reproducibility with the same parts. The countermeasures involve identifying functional holes on the drawings and confirming them at three stages: before painting, after painting, and before shipping. Since drips and thick films are likely to occur around the holes, we confirm the passage not only visually but also using pins or gauges as necessary. It is important to make functional holes a dedicated focus for verification. Please utilize painting management documents for confirmation. Holes are parts that are directly related to functionality rather than appearance. Creating an important hole list and making it an independent inspection item will help prevent recurrence.

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Masking defects are failures where paint adheres to areas that should not be painted. Areas such as screw parts, contact points, fitting parts, grounding parts, and drainage holes can cause the customer's assembly process to stop even with just one instance of adhesion. Even if it appears as a small overflow visually, it directly leads to functional defects such as screws not fitting, lack of electrical conductivity, or parts not fitting together. Initially, we check the drawing instructions for unpainted areas, the position of masking materials, any lifting, and the number of times they can be reused. The countermeasures involve standardizing four points: masking range, materials used, application procedures, and inspection methods. Additionally, separating pre-work checks from post-painting checks makes it easier to identify forgotten areas, lifting, and misalignment. When reusing masking materials, it is also necessary to check for deterioration and loss of adhesive strength. Please utilize check materials for managing unpainted areas. Since issues with unpainted areas often arise in later processes, having a system to verify them as functional parts before shipment is effective.

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Poor film thickness is a complaint factor that is often overlooked in visual inspections. A coating that is too thin reduces corrosion resistance, while a coating that is too thick can lead to assembly issues at screw parts, fitting parts, and around holes. In other words, film thickness is a management item that affects rust, appearance, and dimensions. Particularly in automotive parts, even a slight difference in thickness after painting can impact assembly and operation. Initially, we check for deviations from the standard values, measurement locations, production lots, and part shapes. The countermeasures involve determining measurement locations, frequency, standard values, and recording methods, as well as understanding where paint adheres easily for each part shape. If the measurement locations change every time within a lot, trends become difficult to see. By fixing the measurement points and comparing them with the production lot, it becomes easier to identify the causes. Managing film thickness also helps prevent dripping, color unevenness, and hole filling. Please utilize check materials for film thickness verification. It is more important to consistently measure the same location than to measure itself. Comparable records will serve as materials for cause investigation.

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Dripping defects are visual defects where the paint flows and leaves streaks. At customer sites, this can become an issue not only in terms of appearance but also as dimensional defects around holes and fitting areas. The cause is not solely the way the operator applies the paint. When three conditions—film thickness, viscosity, and component orientation—overlap, the paint tends to accumulate in one spot. Areas such as corners, downward surfaces, and around holes are particularly prone to dripping. Initially, we check the location of the drips, the direction of painting, how the jig is applied, and the drying time. Countermeasures include determining the discharge amount, gun distance, viscosity, jig orientation, and holding time before drying for each component. By documenting the locations of occurrence with photos or records, we can reflect on which shapes are prone to dripping in future productions. Reducing drips also helps prevent issues like hole filling and film thickness defects. Please utilize verification materials for reviewing painting conditions. Instead of stopping at operator training, reflecting the prone positions for dripping in standard documents for each component will make it easier to prevent recurrence in the next lot.

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Color variations and differences between lots can easily lead to complaints when compared by customers. The cause is not only the color of the paint. Slight deviations in four factors—paint stirring, dilution ratio, film thickness, and curing conditions—can change the appearance even with the same color number. Areas with thinner film thickness have reduced rust resistance, while thicker areas can lead to runs or poor drying, making color variations a sign of quality inconsistency. Initially, we check the differences from the standard sample, the lot in question, the orientation of the painted surface, and the film thickness measurements. The countermeasures involve standardizing stirring time, dilution conditions, measurement locations, and curing temperature, as well as keeping records for each lot. Additionally, using standard samples can reduce judgment discrepancies among workers. Addressing color variations not only improves appearance but also helps prevent film thickness issues and runs. Please utilize process verification materials for reviewing condition management. Relying on sensory judgment for color can lead to recurrence. It is important to use numerical records alongside standard samples and share the criteria for pass/fail on-site.

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The defects on the painted surface are easily found during the customer's visual inspection and can lead to sorting and repainting issues. If the cause is narrowed down solely to the painting booth, it may not be possible to prevent recurrence. The sources that need to be checked are the booth, jigs, work clothing, and transportation routes. Even a single particle of dust can enter under the paint film and create a bump, leading to unstable film thickness in the surrounding area. Additionally, moisture can enter from around the foreign object, potentially leading to rust or peeling. Initially, we check the size of the bump, the surface where it occurred, the location of occurrence, and the reproducibility with the same jig. Countermeasures include determining the cleaning frequency, the cleaning cycle for jigs, management of work clothing, and the arrangement of parts. By recording the production lot, occurrence location, and number of occurrences, it becomes easier to narrow down which process the contamination occurred in. Measures against foreign objects not only depend on equipment but also show differences in daily site management. Please utilize the painting process confirmation materials for inspections. By not only strengthening cleaning but also categorizing where contamination occurred into the four sources, unnecessary measures can be reduced.

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Blisters are troublesome because defects that were not visible at the time of shipment can appear later. A few weeks or a month after delivery, the paint film may swell, leading to complaints from customers. The main causes are three factors: moisture, oil, and rust particles remaining in the substrate. When moisture or foreign substances remain under the paint film, they expand over time, pushing up the paint film. Particularly, edges, welds, and bag-shaped parts tend to retain moisture, making it difficult to detect initial abnormalities through visual inspection alone. In the initial response, we check the diameter of the swelling, the number of occurrences, and the condition of the substrate after removing the paint film. Countermeasures include confirming drying after pretreatment, managing storage time before painting, checking curing conditions, and verifying the film thickness at the edges. Since blisters are also related to rust recurrence and peeling, not viewing swelling in isolation contributes to preventing recurrence. Please utilize pretreatment confirmation materials for investigation. By not just crushing the blisters but also checking the condition beneath the paint film, we can achieve permanent measures rather than mere cosmetic fixes.

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A pinhole may appear to be a small hole, but it is a significant defect that can lead to appearance issues, repainting, and sorting work for our clients. The factors to check are three: oil, moisture, and air. If oil remains on the surface of the material, if moisture does not fully dry after cleaning, or if air is trapped during spraying, any of these can cause gas to escape during curing, appearing as holes on the surface of the coating. Even a single hole can serve as an entry point for moisture and oxygen, potentially leading to rust or blisters. Initially, it is important to check the number of holes, the surfaces where they occur, and the incidence rate within the same lot to distinguish whether they are due to voids in the material or residues from the process. The countermeasures involve recording the temperature and concentration of the degreasing solution, drying time, spraying conditions, and the condition of the material for each process. It is crucial to manage pinholes not just as an appearance issue but as a weakness in corrosion resistance. Please utilize the painting defect check materials for organizing the causes. The countermeasures will differ depending on whether the holes are material-related or process-related. It is important to examine the actual items alongside the process records.

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Claims of rust reoccurrence may be discovered not immediately after delivery, but during storage or before assembly checks. The areas that require particular attention are the ends, around holes, and weld joints. Even if the surface is covered with paint, if red rust, scale, or moisture remains in the substrate, corrosion will progress beneath the paint film. Even a single thin film area can become an entry point for moisture, leading to red rust, blistering, and peeling. Initially, it is important to check the location of rust occurrence, the number of days in storage, the packaging condition, and the variation in film thickness. For permanent measures, it is crucial to connect the five processes of rust removal, degreasing, drying, film thickness confirmation, and pre-packaging checks as one rust prevention management system, rather than viewing them separately. By not attributing the cause solely to the customer's storage conditions and documenting the substrate condition before painting and key area checks before shipment, it becomes easier to reduce recurrence claims. Please utilize confirmation materials for reviewing rust prevention management. Keeping photos of red rust, storage duration, and packaging conditions will make it easier to determine whether to focus on the painting process or the storage environment.

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When contacted by a client regarding "peeling of the paint film during assembly," it is important to confirm the three processes of degreasing, cleaning, and drying before hastily changing the paint. If even a small amount of press oil or cutting oil remains, the oil will volatilize during curing, creating a layer that does not adhere between the substrate and the paint film. Even if the appearance at the time of shipment is good, peeling may become apparent due to the loads from fastening, transportation, and vibration. In the initial response, it is essential to check the production lot, the location of the peeling, and whether the substrate is exposed, and to verify the condition of the pretreatment solution, water drainage after cleaning, drying time, film thickness, and curing conditions against records. Furthermore, to prevent recurrence, it is effective to narrow down the verification items to about five and incorporate them into daily inspections, rather than relying on the operator's intuition. Peeling, rust, and blisters are linked to the same abnormalities in the preceding processes, so it is crucial to check the entire process. Please utilize check materials for confirming measures against painting defects. In physical inspections, documenting the differences with good products through photographs and recording the occurrence location on drawings will make it easier to prioritize countermeasures.

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Hole filling is a defect where bolt holes, drainage holes, positioning holes, etc., are blocked by paint. This issue becomes apparent to customers as problems such as bolts not passing through, not fitting into jigs, or water not draining. Causes include excessive film thickness, painting direction, component posture, jig setup, and paint pooling before drying. It is important to clearly define critical holes on the drawings and manage jig posture, spraying direction, film thickness, and post-paint inspection.

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Masking defects are failures where paint adheres to areas that should not be painted. In automotive parts, issues are likely to occur at screw areas, contact points, fitting parts, grounding areas, and drainage holes, and they may be discovered during the assembly process at the customer's site. To prevent misalignment of the masking position, peeling, deterioration of the masking material, and differences in judgment among workers, it is necessary to standardize the range of non-painted areas, the application procedure, and the inspection methods.

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Poor film thickness can lead to complaints in both cases of the coating being too thin or too thick. A thin film lacks corrosion resistance and durability, while a thick film can cause issues such as filling holes, dripping, poor fitting, and problems with threaded areas. In automotive parts, the coating also affects dimensions, so it is important to clarify the measurement locations, measurement frequency, and recording methods, as well as to manage how the paint adheres for each part shape.

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The defect is an appearance issue where the paint flows on the coated surface, creating streaks. At the customer’s site, not only the appearance but also the dimensions and assembly can be problematic. The causes include excessive spraying, reduced viscosity, gun distance, posture before drying, and paint pooling due to the shape of the parts. Preventing recurrence can be achieved not only by the skill of the operator but also by standardizing the film thickness criteria, discharge amount, jig posture, and holding time.

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Complaints about color differences between lots, even with the same color number, or partial color unevenness are directly related to the appearance quality of automotive parts. The causes include insufficient mixing of the paint, variations in dilution rates, differences in film thickness, painting distance, curing temperature, and drying time. Color unevenness can also be a sign of unstable film thickness or poor curing, so it is important to standardize paint conditions, film thickness measurements, and curing conditions.

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If there are blemishes or dirt on the painted surface, it may result in a defective judgment during the customer's visual inspection. The causes of foreign matter contamination are varied, including dust in the painting booth, fibers from work clothes, dirt on jigs, adhesion during transport, and foreign matter in the paint. The areas with foreign matter may have thinner paint layers, which can lead to rust or peeling. Cleaning, air management, jig cleaning, and checking the transport route are fundamental measures to address this issue.

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Blistering is a defect where the coating film swells, which may not be visible at the time of shipment but can be discovered by customers weeks or months later. The causes include residual moisture, oil, corrosion products in the substrate, instability of chemical treatment, and insufficient adhesion. Since corrosion and expansion progress beneath the coating film, it cannot be completely prevented by visual inspection alone. It is important to review the drying confirmation after pretreatment, rust removal, curing conditions, and storage time management.

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A pinhole is a surface defect characterized by the occurrence of small holes in the paint film. If discovered during the customer's visual inspection, sorting and repainting may be necessary. Causes include oil and moisture on the material surface, air entrapment, voids, paint viscosity, and unstable drying conditions. Even small holes can lead to reduced rust resistance, blistering, and the recurrence of rust, so it is important to check the degreasing, drying, and spraying conditions.

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If red rust occurs after delivery or during storage, it can lead to concerns about rust prevention quality for customers. Rust reoccurrence can be caused by remaining rust, scale, oil, moisture, and thin film on the material. Particularly, edges, areas around holes, and welds are places where corrosion factors are likely to remain. Reviewing the entire process, including substrate confirmation before painting, rust removal, degreasing, chemical treatment, film thickness management, and packaging conditions, is effective in preventing reoccurrence.

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When paint peeling occurs during the assembly of automotive parts, it leads to significant complaints from customers due to poor adhesion. The causes can lie not only in the paint itself but also in insufficient degreasing, residual oil, instability of the chemical conversion coating, and inadequate surface roughness, which may be hidden in the pretreatment process. Even if the parts appear to be good during visual inspection, they can delaminate under the stress of fastening and transportation, so it is important to review degreasing, cleaning, drying, and film thickness verification at each stage of the process.

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In blister prevention, it is important to check not only the paint and curing conditions but also the chemical treatment process. If the chemical film is not sufficiently formed, the adhesion between the coating and the material decreases, making it easier for moisture and oxygen to penetrate. As a result, corrosion progresses inside the coating, leading to blistering and peeling. Since the chemical film is difficult to see, managing the concentration of the treatment solution and the treatment time is key to ensuring quality stability.

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Blisters may not appear immediately after painting, but can occur months later. If there is slight moisture or foreign matter left inside the paint film, and if there is insufficient chemical treatment or degreasing, adhesion can decrease, allowing moisture and oxygen to penetrate and cause corrosion. As a result, this manifests over time as blisters on the surface. This is not a sudden defect, but rather a manifestation of issues that began before painting, indicating that a review of the entire pretreatment process is necessary.

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Blistering is a defect where the surface of the coating swells, which can lead to peeling or the recurrence of rust over time. The main causes are moisture or foreign substances remaining inside the coating. If moisture is left due to insufficient drying or inadequate chemical treatment, it can combine with moisture that has entered from the outside, creating pressure within the coating. Since the cause is not easily identifiable by just looking at the surface, it is important to check the pretreatment process and drying conditions.

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Insufficient drying after cleaning is a commonly overlooked cause of pinhole defects. In parts with complex shapes or bag holes, moisture tends to remain, and at baking temperatures around 180 degrees, it can rapidly evaporate and break through the coating. Residual moisture can lead not only to pinholes but also to blisters, adhesion failures, and the recurrence of rust. In environments where humidity exceeds 70 percent, managing drying time and air blow conditions is crucial.

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If pinholes do not decrease, the cause may lie in the degreasing process rather than the paint or film thickness. Cutting oils and press oils are difficult to confirm visually and can volatilize during the baking process, creating bubbles within the paint film. Residual oil not only leads to pinholes but also serves as an entry point for complex defects such as poor adhesion, blisters, and paint peeling. Managing the temperature, concentration, and replacement timing of the degreasing solution contributes to quality stability.

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A pinhole is a defect that occurs when small holes appear on the surface of a coating. In die casting and casting, it occurs when gas trapped inside the material expands during baking and breaks through the coating. When residual gas loses its escape route at around 180 degrees Celsius, it can lead not only to appearance defects but also to a decrease in rust prevention performance. The presence of oil and moisture can also cause similar issues, so reviewing preheating and drying conditions is effective.

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Aluminum products are lightweight and have excellent corrosion resistance, but they are made of a material that has a smooth surface, making it difficult for coatings to adhere. If the surface roughness is insufficient, adhesion strength may decrease, leading to peeling or chipping after a few months. It is important to create an appropriate roughness through blasting or chemical treatment to increase the contact area with the coating. Before changing the paint, it is necessary to confirm the pre-processes, including degreasing, chemical treatment, and roughness management.

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If paint peeling recurs, simply reviewing the baking temperature may not lead to improvement. Even if conditions such as 180 degrees for 20 minutes are followed, insufficient degreasing or poor chemical treatment can reduce adhesion. Abnormalities in previous processes may surface months later as peeling, blistering, or rust reoccurrence. It is necessary to confirm the entire process, including degreasing, drying, and chemical treatment, rather than just raising the temperature as a countermeasure.

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Paint peeling is a typical defect caused by issues in the pre-painting process, such as insufficient degreasing or inadequate chemical treatment. If press oil or cutting oil remains during curing, the oil will volatilize at around 180 degrees, creating tiny spaces between the paint film and the substrate. As a result, peeling occurs due to vibrations or impacts. Even if the surface looks clean, there may still be residual oil or oxidation films, making it important to manage the numerical values of pre-treatment conditions.

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In the telecommunications equipment industry, particularly for components like antenna bases, the adhesion of paint is crucial for maintaining product reliability. Residual release agents and processing oils on the material surface can hinder paint adhesion and lead to coating delamination. Even trace amounts of oil, which are difficult to detect visually, can result in reduced adhesion after painting and potential peeling weeks later. Additionally, insufficient degreasing can also lead to the occurrence of blisters and pinholes. When the degreasing process is shortened to improve productivity, it is not uncommon for the costs of re-coating or handling complaints to increase as a result. The first step in addressing poor adhesion issues is to standardize the degreasing process and review management conditions. Our technology addresses these challenges and provides stable painting quality. 【Application Scenarios】 - Painting of telecommunications equipment and antenna bases - Painting of components that are prone to adhesion of release agents and processing oils - Products requiring long-term coating reliability 【Benefits of Implementation】 - Reduction in complaints due to poor paint adhesion - Decrease in re-coating costs - Improvement in product reliability

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In the painting of OA equipment enclosures, the adhesion of the paint film is emphasized to ensure the product's appearance quality and durability. Particularly in the case of aluminum die-cast materials, poor adhesion of the paint can easily occur due to the adhesion of release agents or processing oils, which can lead to peeling or deterioration of appearance. Even trace amounts of oil, which are difficult to detect visually, can cause issues such as peeling of the paint film, blisters during the curing process, and pinholes. When the degreasing process is shortened to improve productivity, it is not uncommon for the costs of re-coating or handling complaints to increase as a result. As the first step in addressing adhesion issues, standardizing the degreasing process and reviewing management conditions are essential. 【Usage Scenarios】 - Painting of aluminum die-cast OA equipment enclosures - Products requiring appearance quality and durability - Cases facing challenges in managing the degreasing process 【Benefits of Implementation】 - Reduced risk of peeling due to improved paint film adhesion - Suppression of painting defects such as blisters and pinholes - Reduction in costs for re-coating and handling complaints - Enhanced appearance quality and reliability of the product

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In the painting of home appliance housings, the adhesion of the paint film is extremely important to ensure product quality and durability. Particularly in the case of aluminum die-cast materials, poor adhesion due to the presence of release agents or machining oils can easily lead to paint film peeling, which can not only result in poor product appearance but also potentially lead to functional degradation. Even trace amounts of oil that cannot be visually confirmed can affect adhesion after painting and may manifest as defects over time. Additionally, insufficient degreasing can lead to the occurrence of blisters and pinholes, potentially causing defects during the curing process. When the degreasing process is shortened to improve productivity, it is not uncommon for the costs of re-coating or handling complaints to increase as a result. As the first step in addressing poor adhesion, standardization of the degreasing process and a review of management conditions are required. 【Application Scenarios】 - Painting of aluminum die-cast home appliance housings - Products where appearance quality is emphasized - Products requiring long-term durability 【Benefits of Implementation】 - Reduction of peeling defects due to improved paint film adhesion - Suppression of blister and pinhole occurrence - Reduction of re-coating and complaint handling costs - Stabilization of product quality and improvement of reliability

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In the automotive parts industry, particularly in the painting of critical components like engine blocks, high adhesion and durability are required. Poor painting can directly lead to a decline in product performance and early deterioration, potentially compromising reliability. Specifically, release agents and machining oils that adhere to aluminum die-cast products are difficult to detect visually but can cause poor paint adhesion, blisters, and pinholes. These defects may not be apparent in the initial stages but can later lead to peeling and performance degradation. If the degreasing process is shortened to improve productivity, it is also necessary to consider the risk of increased costs for repainting or handling complaints. As the first step in addressing poor adhesion, standardizing the degreasing process and reviewing management conditions are essential. 【Application Scenarios】 - Painting of automotive parts like engine blocks that require high adhesion - Painting of aluminum die-cast products that are prone to adhering release agents and machining oils - Aiming to reduce repainting and complaint handling costs due to poor painting 【Benefits of Implementation】 - Improved product quality through reduced paint adhesion issues - Suppression of blister and pinhole occurrences - Reduction of repainting and complaint handling costs - Stabilization of the entire painting process and enhancement of reliability

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In the hull of marine parts, durability and reliability under harsh environments are required. In particular, the painting of aluminum die-cast parts poses a significant challenge, as poor adhesion of the paint film can directly affect product lifespan and safety. Paint peeling can be caused by various factors such as salt damage, water pressure, and physical impacts, but one of the root causes is inadequate degreasing processes. Residual release agents and processing oils on the material surface hinder direct adhesion between the paint and the material, and even trace amounts of oil that are not visible can compromise long-term durability. While there may be no issues immediately after painting, peeling can occur over time, often leading to additional costs such as re-coating or handling complaints. The first step in addressing poor adhesion is to standardize the degreasing process and review management conditions. 【Application Scenarios】 - Painting of hull parts for ships - Use in harsh marine environments - Ensuring long-term durability of the paint film 【Benefits of Implementation】 - Reduction of paint peeling risks - Improvement of product reliability - Reduction of re-coating costs

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Paint peeling is a defect where the paint film lifts from the material and gradually comes off during use. This not only reduces the appearance quality but also affects the entire manufacturing site, as the peeled paint film can adhere to other products. Importance of the degreasing process: Insufficient degreasing is the main cause of paint peeling. By maintaining the degreasing solution temperature above 50 degrees, the oil removal efficiency improves by 60 percent. Regularly replacing the degreasing solution (every 7 days) can keep the degreasing efficiency consistently above 95 percent. Optimization of chemical treatment: By managing the chemical treatment film thickness within plus or minus 1 micron and maintaining a thickness of 8-10 microns, adhesion is maximized. Keeping the crystal diameter between 5-15 microns enhances long-term adhesion. Impact of humidity management: If the humidity just before painting is above 70 percent, moisture adheres to the material surface, leading to poor adhesion. It is essential to ensure a drying time of one hour before painting and to manage humidity below 50 percent. Our company optimizes degreasing, chemical treatment, and drying, achieving a 10-year warranty against paint peeling. We also guarantee quality even for small lot short delivery requests.

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Chipping is a defect where the coating film chips off due to mechanical impact. It is particularly prone to occur in automotive parts, with cases of customer complaints arising from impacts in the usage environment after delivery accounting for 30-40 percent. Relationship between film thickness and chipping resistance: At a thickness of 20 microns, the film easily peels off under impact (damaged at an impact value of 30J), while at 30 microns, it withstands 60J, and at over 40 microns, it achieves impact resistance of over 150J. Designing the film thickness according to the application of the parts is essential. Quantifying adhesion: In cases of poor adhesion, even at a thickness of 40 microns, the impact value drops to 60J. By optimizing degreasing and chemical treatment to ensure adhesion, the impact resistance can be improved by more than double at the same film thickness. Influence of surface treatment: Maintaining a surface roughness Sa of 2-3 microns strengthens the mechanical interlocking with the coating film, improving chipping resistance by 30 percent. Optimizing shot blasting conditions is key. Our company combines film thickness management (40 plus or minus 5 microns), ensuring adhesion, and proper surface treatment to achieve a chipping occurrence rate of less than 0.5 percent. This has also been adopted in automotive parts.

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Poor curing refers to a state where the coating film does not cure sufficiently, resulting in a dent when pressed with a finger. It can crack in a pattern resembling a spider web or peel off due to friction, significantly reducing durability. It accounts for 10-15 percent of all defects on average in the industry. Precision in curing temperature: Raising the curing temperature from 150 degrees to 160 degrees improves hardness (pencil hardness) from H to 2H. Furthermore, increasing it to 170 degrees to 180 degrees can achieve up to 3H. However, a management precision of plus or minus 10 degrees is essential. Measured data on curing time: At 180 degrees, a curing time of 20 minutes reaches a hardness of 2H, 30 minutes reaches 3H, and 60 minutes reaches 4H. The required curing time varies depending on the size and thickness of the parts. Differences in conditions based on resin type: Alkyd resin is sufficient at 160 degrees, but melamine resin requires 180 degrees. Polyester resin is recommended at 190 degrees. Understanding the chemical properties of the resin is essential for setting conditions. Our company has established a curing condition matrix based on part size, material, and resin type, ensuring a stable supply of hardness above 4H. We can also guarantee wear resistance.

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Reoccurrence of rust is a phenomenon where rust occurs beneath the paint film 3 to 6 months after painting, causing the paint film to swell. This is particularly common in pressed and cast products, and if it leads to a return claim within the quality assurance period, the cost for replacement or repair amounts to 150,000 to 250,000 yen per case. Importance of conversion coating thickness: When managing the conversion coating at 5 microns, 15-20 percent rust reoccurrence occurs within 2 years. If the thickness is increased to 8-10 microns, the rust reoccurrence rate during the same period is reduced to below 2 percent. Crystal structure of phosphate treatment: The larger the crystals in the conversion treatment, the higher the corrosion resistance. By managing the crystal diameter between 5-15 microns, it is possible to clear 1000 hours in the salt spray test (JIS Z 2371). Combination effect with pretreatment: Optimizing the three stages of degreasing, oxide film removal, and conversion treatment improves corrosion resistance by more than three times compared to just conversion treatment alone. Similar measures are necessary even for stainless materials. Our company manages the conversion coating thickness within plus or minus 1 micron and offers a 5-year rust-free guarantee. We have also achieved no rust generation even after 1500 hours in the salt spray test.

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Gloss unevenness is a defect where the gloss of the coating surface varies by location, appearing as a mottled pattern. Particularly in automotive interior components, it diminishes the sense of luxury, with data indicating that customer satisfaction can decrease by 30-40 percent. Variation in gloss due to film thickness: When the film thickness changes by plus or minus 30 microns, the angle of light reflection changes, resulting in a 10-15 percent fluctuation in gloss. Strict control within plus or minus 20 microns can reduce gloss unevenness by 90 percent. Optimization of the drying environment: The optimal drying time is in an environment with a temperature of 25 degrees and humidity of 50 percent (30 minutes). Higher temperatures and lower humidity lead to excessively fast drying, causing uneven solvent evaporation and lower gloss in certain areas. Conversely, lower temperatures and higher humidity result in slower drying and sedimentation. Fine-tuning the baking temperature: Raising the baking temperature from 170 degrees to 180 degrees changes the curing speed of the resin, resulting in more uniform gloss. However, if raised too much, drips can occur, necessitating strict control within plus or minus 5 degrees. With our constant temperature and humidity chamber and temperature management system, we achieve a gloss unevenness occurrence rate of 0.1 percent, guaranteeing a luxurious paint finish.

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Foreign matter contamination is a phenomenon where dust, oil, moisture, and other debris attached to the paint film result in defects. If discovered during the inspection process, it incurs costs of 300,000 to 500,000 yen for re-cleaning and repainting, and if overlooked and delivered, it leads to customer complaints (return rate: 20-30 percent). The main cause is insufficient management of the cleaning solution: when the viscosity of the cleaning solution is high, fine debris settles and adheres to the product surface upon reuse. If the cleaning solution is not changed for more than two weeks, the contamination rate can soar to 70-80 percent. Quantifying filter efficiency: after using a filter for 500 hours, the filtration efficiency decreases by 60 percent compared to the initial value. By replacing the filter every 250 hours, the contamination rate can be maintained below 0.5 percent. Contamination countermeasures from the water supply pipe: fine scale and rust in the water supply can be dispersed by air blow and adhere to the product in 25 percent of cases. Regular replacement of the water supply filter (once a month) can virtually eliminate contamination from this route. Our company replaces the cleaning solution every five days, manages filters for 250 hours, and conducts monthly replacements of the water supply filter. The contamination rate is below 0.2 percent.

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Color variation is the difference in light refraction caused by varying film thickness in different areas. Even with the same color number, if there is variation in film thickness, the color may appear different, leading to a rejection rate of about 35 percent in visual inspections. The numerical target for film thickness management: managing the thickness within plus or minus 20 microns reduces the occurrence of color variation to below 5 percent. If the current management is within plus or minus 50 microns, simply improving to plus or minus 30 microns will reduce color variation by 60 percent. Optimization of spray distance and pressure: By maintaining the spray distance at 20 cm and the pressure within plus or minus 10 percent of 3.0 kg/cm², film thickness variation can be controlled to plus or minus 25 microns. The introduction of automatic spraying equipment improves film thickness accuracy by eight times compared to manual work. The impact of drying speed: If drying is too fast, solvents evaporate unevenly, resulting in thicker areas of the film. Ensuring an appropriate drying time (30 minutes at 25 degrees) achieves a 70 percent prevention rate for color variation. With our automatic spraying system and film thickness management, we achieve zero occurrences of color variation, enabling both quality improvement and production efficiency.

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Dripping occurs due to poor coating film, which not only leads to appearance defects but also induces poor curing in thick film areas. On average, it accounts for 8-12 percent of all painting defects in the industry. Relationship between viscosity and curing temperature: The lower the paint viscosity and the higher the curing temperature, the more likely dripping occurs. Even with the same viscosity of paint, simply raising the curing temperature from 160 degrees to 180 degrees can increase the dripping occurrence rate from 20 percent to 60 percent. Response to seasonal variations: The viscosity of paint can change by up to 40 percent between winter (5 degrees) and summer (25 degrees). Without proper viscosity management, the defect patterns will vary with each season, making it difficult to identify the causes. Optimal viscosity by material: Aluminum die casting has an optimal viscosity of 20 seconds (Ford cup), zinc die casting 18 seconds, and stainless steel 22 seconds. It is necessary to address the differences in surface tension by material. Our company has implemented daily management using a viscometer and an automatic adjustment system based on material and season, keeping the dripping occurrence rate below 2 percent.

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Blistering is a defect where the paint film swells during the cooling stage after baking, creating cavities between the paint film and the substrate. Once it occurs, the paint film peels off due to temperature changes in the usage environment, resulting in a high complaint rate after delivery, second only to paint peeling (industry average: 15-20 percent). The risk of double gasification: At a baking temperature of around 150 degrees, residual oil vaporizes, and moisture absorbed by the substrate turns into steam. When these two gases are generated simultaneously, pressure increases under the paint film, and there is data showing that the blistering rate can reach 85 percent. Optimal temperature for degreasing solution: Keeping the degreasing solution above 50 degrees improves oil removal efficiency by 60 percent. Additionally, moisture after chemical treatment can be removed by 95 percent with heating and drying at 80 degrees for 3 minutes. Response to stainless steel materials: Stainless steel absorbs more moisture on its surface than aluminum (1.5 times more), making it incompatible with conventional conditions. It is essential to set pre-treatment conditions specific to each material. Our company has established optimal degreasing and drying conditions for each material, achieving zero blistering.

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Pinhole defects are caused by countless tiny holes forming on the surface of the paint film. In automotive parts, this results in appearance defects that can lead to complaints, with cases where delivery delays and re-manufacturing costs increase by an average of 200,000 to 300,000 yen. The importance of the degassing process: Many sites tend to think that "the quality of the paint is low," but in reality, gases remaining in aluminum die-cast or pressed products expand at a curing temperature of 180 degrees and form holes when released from the surface of the paint film. Humidity management is crucial: In environments with humidity over 60 percent, moisture absorbed by the material vaporizes, increasing the pinhole occurrence rate by 40 to 50 percent. By simply heating at 100 degrees for 5 to 10 minutes in the pre-curing process, the occurrence rate can be reduced by 70 percent. The effect of pre-degreasing: By setting the temperature of the degreasing solution to 55 degrees and ensuring a soaking time of 3 to 5 minutes just before painting, the amount of gas inside the material can be reduced by up to 80 percent. Addressing pinholes is not about changing the paint but optimizing pre-treatment and environmental management. Our company optimizes the degassing conditions for each material in small lots, achieving high-quality painting.

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One of the most common causes of poor adhesion in aluminum die-cast painting is insufficient degreasing. If painting is done while release agents or processing oils remain on the surface of the material, the paint cannot adhere directly to the material, leading to paint film peeling. Particular attention should be paid to oil residues that cannot be confirmed visually. Even if the surface appears clean, just a small amount of oil residue can significantly reduce adhesion. While the painted surface may look fine immediately after painting, there are cases where peeling occurs weeks later. Moreover, insufficient degreasing not only leads to poor adhesion but can also cause blisters and pinholes. This is because oils can volatilize during the curing process at around 180°C, causing defects within the paint film. In practice, there may be attempts to shorten the degreasing process to improve productivity, but this often results in increased costs for re-coating or handling complaints. The first step in addressing poor adhesion is to standardize the degreasing process and review the management conditions. We have prepared materials summarizing examples of defects caused by insufficient degreasing and points for improvement. Please use them as reference materials for process improvement.

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