ナイカイ企業 List of Products and Services

There are occasional reports of "sudden clogging during filling of the container bag, resulting in overflow." This occurs when the filling material comes into contact with the inner bag, causing it to be dragged down, leading to a shortage of the upper inner bag and preventing the contents from spreading evenly to the top corners. As a countermeasure, it is important to fully inflate the inner bag with air, ensure that it properly conforms to the container bag, and maintain this state. This allows the contents to fill the inner bag completely. Additionally, there is a solution by securing (sewing) the outer bag of the container bag to the inner bag. 【Countermeasures】 ■ Fully inflate the inner bag with air, ensure that it properly conforms to the container bag, and maintain this state. ■ Secure (sew) the outer bag of the container bag to the inner bag. *For more details, please refer to the PDF document or feel free to contact us.

When discharging the product, the inner bag shifts and comes out from the discharge port. We are adjusting it using a hoist crane, but it has exceeded the limit, causing the inner bag to bend and get stuck above the receiving hopper opening. As a countermeasure, we can sew tape in the center of the belt to prevent the tied part of the inner bag in the charging tube from falling down, and connect it below the knot of the inner bag in the charging tube, which will stop the inner bag from dropping. However, if there are height restrictions for lifting, it may get stuck at the receiving hopper opening. In that case, by attaching a flap to the "Smart Liner" produced by our company, it becomes possible to integrate the outer bag of the container back with the inner bag, preventing the inner bag from shifting while significantly improving the filling performance. 【Countermeasures】 - Sew tape in the center of the belt to prevent the tied part of the inner bag in the charging tube from falling down, and connect it below the knot of the inner bag in the charging tube. - Attach a flap to the "Smart Liner" produced by our company. *For more details, please refer to the PDF document or feel free to contact us.

The flexible cross container is made by sewing the raw material with sewing thread to create a bag, making it a common source of foreign substances. The raw material used for the container bag itself is made of polypropylene or polyethylene, which can generate static electricity. Therefore, even if you think you have disposed of the cut sewing thread, it can still stick to your fingers or adhere to the raw material, which is troublesome. As a countermeasure, it is effective to place a trash can near the sewing machine and cover it with a wet towel or similar item to dissipate static electricity. At Naikai Corporation, we have established a specialized inspection process to remove foreign substances and produce clean products. [Countermeasures] - Create a trash can near the sewing machine - Cover the trash can with a wet towel or similar item to dissipate static electricity - Daily education is important to ensure that items are properly disposed of in the trash can *For more details, please refer to the PDF document or feel free to contact us.

The base material comes in both laminated and non-laminated versions. Laminated base materials are already laminated on one side, which reduces the risk of frayed yarns falling off, leading to many cases where flash cutting is deemed acceptable. However, if there are issues with temperature management during lamination, it becomes difficult to completely prevent detachment from the cut edge, regardless of whether it is laminated. Countermeasures include "performing heat cutting or thermal treatment on the cut edge as needed, even for laminated base materials" and "folding back the base material to sew it in a way that the cut edge does not appear." At Naikai Corporation, thermal treatment is implemented for all products regarding no-contamination products from a risk avoidance perspective. 【Countermeasures】 ■ Perform heat cutting or thermal treatment on the cut edge as needed, even for laminated base materials. ■ Inspect and cut away any foreign substances that have occurred or are likely to occur. ■ Fold back the base material to sew it in a way that the cut edge does not appear. *For more details, please refer to the PDF document or feel free to contact us.

When cutting the original material, it is particularly likely to occur in areas such as the top and bottom surfaces where the input and output tubes are sewn, as well as in the cross-cut (kiku-wari) sections. There are cases where automatic heat press cutting is performed with cutting equipment or where a dedicated iron is used manually, but in either case, if not managed properly, there may be occurrences of burnt spots. If this detaches during the manufacturing process of container bags or during filling and discharging at the customer's site, it can lead to foreign matter contamination. Countermeasures include "managing the cutting heater temperature and cutting speed, and education" or "covering the surface with an over-tape and sewing it." At our overseas factories, we suppress occurrences through technical guidance at the cutting site and foreign matter inspections. Please feel free to consult us. *For more details, please refer to the PDF materials or feel free to contact us.

It is not uncommon for hair and body hair to adhere to the outer and inner surfaces of container bags. This is due to the fact that the fabric used for container bags is made of polypropylene or polyethylene, which generates static electricity, similar to the principle where hair is attracted to a desk mat used in elementary school. As a countermeasure, it is important to use anti-static materials, select the best work clothing, and analyze and identify hazardous areas and causes based on past cases. Naikai Corporation is capable of producing container bags with zero foreign matter for pharmaceutical, optical, and semiconductor applications. If you need container bags for such applications, please feel free to contact us. [Countermeasures] - Use anti-static materials and select the best work clothing - Analyze and identify hazardous areas and causes based on past cases *For more details, please refer to the PDF document or feel free to contact us.

In this document, we will introduce potential issues that may arise when using flexible container bags, as well as examples of solutions to problems that our customers have consulted us about. If you are struggling with any issues that you cannot resolve, please do not hesitate to reach out to us. Based on our half-century of experience, we will answer any small questions you may have. Feel free to contact us anytime. [Contents] ■ Overflow issues during filling ■ Inner bag misalignment issues during discharge ■ Foreign matter adhesion issues inside the container bag *For more details, please refer to the PDF document or feel free to contact us.

Flexible containers and craft paper bags are essential items in the powder handling field. We have compiled the issues raised by customers during use and proposed solutions for them. 【Content (partial)】 ■ Overflow during filling ■ Inner bag misalignment during discharge ■ Foreign matter adhesion inside the container bag ■ Sewing thread of the sewn paper bag fraying ■ Desire to separate the outer layer bag from the inner layer bag *The materials can be viewed via PDF download.

The lifting belt that supports the load, which can be considered the lifeline of a container bag, excels in tensile strength but also has its weaknesses. Let's discuss the causes of accidents where the belt breaks. I believe that cases of lifting container bags with forklifts are overwhelming, but since belts and ropes are made of resin, if the belt is rubbed against the edge of a metal claw during sudden braking, it can melt or degrade due to heat, leading to easy breakage. Design countermeasures include "folding the belt in two," "making the belt double-layered," "covering with raw materials," and "adding further coverage when folded." Our company prevents accidents with reliable designs based on extensive experience. Please feel free to consult us. 【Examples of design countermeasures】 ■ Folding the belt in two ■ Making the belt double-layered ■ Covering with raw materials ■ Adding further coverage when folded *For more details, please refer to the PDF materials or feel free to contact us.

The lifting belt, which can be considered the lifeline of the container bag, supports the load and excels in tensile strength, but it also has weaknesses. Let's discuss the causes of accidents where the belt breaks. If the strength is reduced to lower the product price or if weather-resistant agents are not added, the risk of accidents increases. Container bags have safety strength requirements for use defined by the JIS standard JIS-Z1651. It is required to clear load tests based on the total strength of the lifting points, not just the strength of the lifting belt alone, which determines the tensile load required for the belt's intended use. At Naikai Corporation, we confirm the strength data of the yarn during production and regularly conduct official testing at Japanese industrial testing laboratories to ensure safety. [Naikai Corporation's Safety Confirmation] ■ Confirmation of yarn strength data during production ■ Regularly conducting official testing at Japanese industrial testing laboratories to ensure safety ■ Typically results exceeding 20,000N *For more details, please refer to the PDF document or feel free to contact us.

The suspension belt that supports the load, which can be considered the lifeline of a container bag, excels in tensile strength but also has its weaknesses. Let's discuss the causes of accidents where the belt breaks. The material of the belt is primarily made of PP resin. PP resin is prone to degradation from ultraviolet rays in sunlight, and when exposed to UV light, the electronic chains can break, leading to a decrease in strength and, in severe cases, powdering. If weathering agents are not properly added, even indoor storage can cause significant damage over time from light entering through warehouse windows. However, it is possible to take measures depending on the amount of UV weathering agents added and the color of the material. Our company manufactures products with a 3-year or 5-year warranty for weather resistance by incorporating specific weathering agents and using black pigments that are less permeable to light. [Measures] ■ Add specific weathering agents ■ Use black pigments that are less permeable to light → Our company also manufactures products intended for outdoor use, such as sandbags, with 3-year or 5-year warranties. *For more details, please refer to the PDF document or feel free to contact us.

Containers filled with contents are being stored in the warehouse, right? However, does that storage method comply with the specifications of the containers? Let's avoid storing beyond the designed stacking height. When the initial filling has air trapped in it, it is unstable, and there is a possibility that the contents may shift inside, which can lead to a greater tilt. As a general rule, stacking should be limited to two layers, and instead of stacking on poles, please use a staggered stacking method (tiered stacking). If stacking more than three layers, please utilize racks or similar equipment to prevent collapse. [Measures] ■ Do not store beyond the designed stacking height ■ Limit stacking to two layers ■ Use staggered stacking instead of pole stacking ■ Utilize racks or similar equipment when stacking more than three layers *For more details, please refer to the PDF document or feel free to contact us.

In Japan, traditionally, round containers have been common, but there seem to be many cases where they are being replaced by the rectangular shapes that are mainstream overseas. On the other hand, while the rectangular shape has its advantages, it also requires careful handling during filling, and there are both merits and demerits. The shape of the bottom is more advantageous for stacking with rectangular shapes than with round ones. However, simple rectangular shapes tend to become round after filling, leading to the flow of contents, and there is a tendency for the shape to gradually change. If using a rectangular container with partitions, it becomes possible to maintain the rectangular shape further, improving stability during storage. Of course, this maximizes loading efficiency, allowing for effective use of warehouse space. Additionally, the double-partition type is a revolutionary container with a new design that is effective for long-term storage in refrigerated warehouses for highly flowable materials such as grains. 【Solution】 <Rectangular container with partitions> ■ It is possible to maintain the rectangular shape ■ Stability during storage is improved 　→ Maximizes loading efficiency, allowing for effective use of the warehouse *For more details, please refer to the PDF materials or feel free to contact us.

"The contents were filled into the bag, and just after stacking, the bag slipped and fell." "While transporting on a pallet with a truck, the bag slipped and fell." This is a common case reported by customers, and falls can lead to bag ruptures and potentially serious accidents. The cause of the bag slipping is that the paper fibers on the surface of the bag become flattened and smooth, resulting in a reduced coefficient of friction. Our company can apply anti-slip processing to both the front and back surfaces. By coating the base paper with an anti-slip agent, we can increase the coefficient of friction and make it less slippery. [Countermeasures] ■ Apply anti-slip agent to the base paper ■ Increase the coefficient of friction to reduce slipperiness *For more details, please refer to the PDF document or feel free to contact us.

"When we stacked the pallets, the bags were damaged." "After filling, when transported to the customer, they were torn." As we manufacture packaging containers, we cannot overlook this issue. The cause of the bags tearing is insufficient strength. The bags cannot withstand the weight of the contents. This problem can be resolved simply by changing the kraft paper. Increasing the basis weight of the kraft paper or switching to processed paper (cross kraft) will enhance its strength. [Countermeasures] ■ Increase the basis weight of the kraft paper to enhance strength Example: K75g/m2 → K78g/m2 ■ Changing the kraft paper to processed paper (cross kraft) will increase strength (Cross woven with PE or PP yarn laminated onto kraft paper) *For more details, please refer to the PDF document or feel free to contact us.

When wearing gloves, it can be difficult to even pinch the sewing thread... Taking off the gloves just to open something is a hassle, and wearing gloves is essential for the task. However, it’s also frustrating when it takes a long time to open something. Our company offers the "Easy Open Bag" that can solve this problem. It has a cut tape on the opening, allowing you to simply pull the tape to open it. No scissors are needed, and it’s not a problem if you’re wearing gloves. Additionally, it doesn’t produce any thread debris from the sewing thread, which helps prevent foreign matter contamination. 【Countermeasures】 ■ Use the Easy Open Bag - Easy to open with cut tape, no problem even when wearing gloves - Just pull the cut tape, no scissors needed, increases efficiency - No thread debris from sewing thread, also helps prevent foreign matter contamination *For more details, please refer to the PDF document or feel free to contact us.

When you try to use it, the contents are damp and clumped together... The issue of the contents inside the bag becoming humid is troubling many customers. Craft paper has high moisture absorption due to its natural fibers, causing the paper bag to absorb moisture, which then permeates into the contents and makes them damp. As a countermeasure, by adding PE, AL, and WS to the inner layer, it is possible to enhance moisture resistance and protect the contents from humidity. Our company specializes in moisture-proof processing for the inner layers of sewing bags, bottom-sealed bags, and easy-open bags, particularly excelling in incorporating aluminum into bottom-sealed bags. [Countermeasures] - Moisture-proof processing for the inner layers of sewing bags, bottom-sealed bags, and easy-open bags - Use of PE (polyethylene) inner bags and sheets in the inner layer of the paper bag - Use of AL (aluminum) sheets in the inner layer of the paper bag - Use of WS (wet-strength paper) in the paper bag *For more details, please refer to the PDF materials or feel free to contact us.

The information printed on the paper bag includes the product name, ingredients, precautions, legal markings, and other important details. If this information is not clearly visible, it could lead to troubles or accidents. Updating the design? That is one solution, but there are limitations to the printable area. As a countermeasure, let's try changing the type of ink used for printing. Each type of ink has its own characteristics, with advantages and disadvantages. If the ink printed on the paper bag is oil-based, how about switching to water-based ink? When changing from oil-based to water-based, there is no need to remake the printing plate. [Countermeasures] - Try changing the type of ink used for printing - Oil-based - Water-based - Organic solvent-based *For more details, please refer to the PDF document or feel free to contact us.

The sewing thread of the sewn paper bag is fraying! Have you ever experienced this when trying to fill the paper bag with contents or when attempting to transport and open the filled paper bag? The cause is that the crepe sewing part of the sewn paper bag can come into contact with or get caught on other objects during transportation or while working. If you continue working or transporting without noticing that the sewing thread is fraying, there is a risk that the contents could leak from that area in the worst-case scenario. By applying an over-tape process, you can solve the problem of fraying sewing threads. [Countermeasures] <Over-Tape Processing> ■ Covers and protects the sewing seams of the sewn paper bag ■ Prevents the sewing thread from coming undone at the ends ■ Since the sewing thread does not protrude externally, it prevents foreign matter from mixing in ■ It is also possible to prevent leakage of the contents *For more details, please refer to the PDF document or feel free to contact us.

There was a request to use a paper bag (outer layer) and a PE film bag (inner layer) separately. At Naikai Corporation, it is possible to manufacture paper bags that can be separated even during simultaneous bag production. The "Polyethylene Inner Layer Bag Insertion Bag" allows for the outer layer bag and inner layer bag to be separated and removed, making it suitable for food raw material applications and pharmaceutical raw material applications where contamination prevention is necessary. When sealing the filled contents, the PE bag, which is the inner layer, is tied with a rubber band or similar to seal it. 【Features of the Polyethylene Inner Layer Bag Insertion Bag】 ■ A paper bag with a longer PE bag inserted as the inner layer than the outer layer bag (kraft paper bag) ■ When sealing the filled contents, the PE bag, which is the inner layer, is tied with a rubber band or similar to seal it ■ The outer layer bag and inner layer bag can be separated and removed ■ Suitable for food raw material applications and pharmaceutical raw material applications where contamination prevention is necessary *For more details, please refer to the PDF document or feel free to contact us.

There was a request to separate and use the paper bag (outer layer) and the PE film bag (inner layer). At Naikai Corporation, it is possible to manufacture paper bags that can be separated even during simultaneous bag production. The "Back-in-Back Bag" uses a special adhesive (release adhesive), allowing for easy separation and removal of the inner layer bag (such as PE film bags). This bag is suitable for applications requiring foreign matter contamination prevention, such as food ingredients, pharmaceutical materials, and even optical resin applications. 【Back-in-Back Bag Features】 ■ Uses a special adhesive (release adhesive) ■ Allows for easy separation and removal of the inner layer bag (such as PE film bags) ■ Adopts an easy-open feature ■ Reduces the introduction of foreign matter into clean rooms, etc. ■ Facilitates easy sorting when disposing of the bag *For more details, please refer to the PDF document or feel free to contact us.