ABOUT US

About KUROIWA

ABOUT US

The philosophy embodied in “Yajirobe”

Kuroiwa’s logo is derived from the “Yajirobe” traditional balance toy,
symbolizing our belief that “balance is everything” in die creation.
True value arises not from merely selecting high-performance parts,
but from each element functioning in optimal balance.

The philosophy embodied in “Yajirobe”

Kuroiwa’s logo is derived from the “Yajirobe” traditional balance toy,
symbolizing our belief that “balance is everything” in die creation.
True value arises not from merely selecting high-performance parts,
but from each element functioning in optimal balance.

One - Stop

The combinations are endless.
There is a vast array of choices in die cutting.

We propose custom dies optimized for material
and processing needs, balancing the entire structure for each customer.

High - Quality

Kuroiwa’s Strength

Kuroiwa’s strength lies in its “three pillars.”
Though they may appear distinct fields, the technologies can be widely applied across them.

Flexible Packaging Dies

Styrene Tray Dies

Paper and Cardboard Packaging Dies

These pillars resonate together,
forming one strong foundation that drives technical strength, quality, and efficiency.
This has become the basis of Kuroiwa’s unique position in the industry.

Total - Balance

Leveraging Kuroiwa’s solid foundation,
we handle every process in-house — from die fabrication to actual application
including the processing of all necessary materials and auxiliary components.
We achieve cost reduction, shorter lead times,
and strict quality control by eliminating the need for outsourcing.
We also place great emphasis on after-sales support,
introducing inspection measurement equipment to replace conventional visual checks,
enabling more accurate and highly precise inspections.

Leveraging Kuroiwa’s solid foundation,
we handle every process in-house — from die fabrication to actual application
including the processing of all necessary materials and auxiliary components.
We achieve cost reduction, shorter lead times,
and strict quality control by eliminating the need for outsourcing.
We also place great emphasis on after-sales support,
introducing inspection measurement equipment to replace conventional visual checks,
enabling more accurate and highly precise inspections.

Evolution of Die Cutting

Traditionally, bending the rule to a radius smaller than roughly R0.7 was the limit, but introducing broaching now lets us process down to R0.3.
Areas that once required mitered joints (sumikiri) at the blade tip can now be formed with bending alone.
Even when a joint is unavoidable, we can handle it without performing corner trimming.

Complex die shapes once suffered from uneven cutting pressure and limited durability.
Joints were also unreliable, causing frequent issues during Thompson die cutting and making these shapes unpopular.
Today, advances in technology and machine performance have dramatically increased bending accuracy,
significantly reducing trouble while greatly improving durability.

Board stock containing recycled fiber (such as Hansol paper) or specialty sheets coated with phosphorescent materials used to cause blades to wear rapidly.
We have since developed blades that can handle these specialty papers, dramatically improving durability.

We previously used magnesium intaglio plates with nylon relief plates for embossing.
By adopting a method that leverages creasing rules and CAD-generated relief surfaces,
we can now emboss across crease lines, perform multi-step embossing,
and deliver significant cost reductions even for large-format embossing.

By forming stainless-steel hooks on the female stripping plate and ejecting waste with the male die,
this stripping die eliminates the need for bottom pins.
Benefits include:
- Eliminates setup time for top and bottom pins on press lines
- Enables stripping even in areas or shapes where inserting bottom pins is difficult
- Provides greater strength and durability than creating hooks in plywood stripping plates
- In-house stainless-steel machining keeps costs low while maintaining short lead times and high precision

Since introducing YAG welding machines, we have been incorporating YAG welding into each process.
For example, we replaced the conventional screw-fastening method on blanking female dies with YAG welding.
This change optimizes designs, reduces part counts, shortens assembly work,
improves product functionality, and prevents the blade edges from opening.

Sculpted blades allow us to build one-piece structures even in areas that once required joints,
without worrying about the blade opening up.

As part of our SDGs initiatives toward a sustainable society, we actively work to reduce plywood waste.
When customers specify plywood dimensions for a die, we choose the most efficient layout from our standard material sizes
and combine offcuts wherever possible so the material is used to its fullest.
This minimizes plywood loss, conserving resources and lowering environmental impact.
We also redesigned the joints between plywood sections to resemble the dovetail scarf joints used in timber construction,
delivering weight reductions and cost savings at the same time.

Production Flow

CONTACT US

Please feel free to contact us anytime.

Head Office

TEL: +8179-266-3628
FAX: 079-266-6810
3-28-33 Aoyamakita Himeji Hyogo JPN

Yumesaki Branch

TEL: +8179-280-3701
FAX: 079-280-3702
1082 Kochinosho Yumesakicho Himeji Hyogo JPN