Kuraray celebrates its 90th anniversary in 2016. We take the opportunity of this occasion to offer you a glimpse of the history of Kuraray from a new perspective. The name Kuraray represents more than 8,300 employees and an annual turnover of approximately 3.7 billion euros. Kuraray was founded in Kurashiki, Japan, in June 1926, by Magosaburo Ohara. Kuraray began with the domestic production of Rayon, a synthetically produced cellulose fibre referred to as artificial silk, a new and innovative product at the time. 

The name KURARAY is derived from the location: Kurashiki and the product manufactured: Rayon. The development of this branch of production developed very quickly in Japan, with many other major manufacturers establishing themselves during this period. Whereas others recruited their technicians and experts from elsewhere, Kuraray established the Kyoko Research Laboratory, which was managed by the University of Kyoto to generate expertise and support for the development of the required technologies. Ohara also committed himself to cultural and social projects. The building of an art gallery and the financing of an orphanage represent only two of his many projects in Kurashiki. The Ohara Museum of Art was the first private museum of Western art in Japan.

Ohara considered the dreadful conditions in which employees commonly worked and lived at the time to be unacceptable; he was not a profit-driven employer, and attempted to solve such issues. He ensured that decent accommodation, fitness facilities and nursery schools were built to provide young employees, or families who had left their homes to work for Kuraray, with everything they needed for education and a healthy and culturally rich lifestyle.
One of the largest general hospitals in the west of Japan, the Kurashiki Central Hospital, was originally founded by Kuraray to promote the well-being of employees and their families. It is still considered to be one of the most famous hospitals in Japan.

With the production of Kuralon in 1950, developed from the in-house manufactured products PVA and vinyl acetate, Kuraray expanded to become the specialist chemical company it is today. Always intent on making a contribution to the good of society, Kuraray addressed the subject of environmental protection very early on. The visionary Ohara was aware of the seriousness of environmental pollution, and made great efforts to prevent it.

Internationally too, Kuraray has remained aware of its social responsibilities. After the war, a production facility was opened in China which helped to improve the poor post-war living conditions of the Chinese population.
Today, Kuraray is a leading global manufacturer of the specialist chemicals used in many aspects of daily life. Kuraray has always viewed its employees as its most important asset, and continues to do so to this day.

During my presentations I am often asked why clinical research into bonding systems is conducted using class V situations.

The non-carious class V lesion is most suitable for this type of research for a number of reasons. Unquestionably, the main reason is the fact that such lesions present little or no macro retention. It must be remembered that if a cavity presents macro retention, loss of adhesive strength in the bonding interface will not automatically lead to loss of retention.

Other major reasons (in no particular order) are that such lesions occur relatively often, but also that in general they are situated in an easily accessible area and do not demand complex restoration technology. The configuration factor is low (ratio between free and bonded areas) and does not therefore cause much shrinkage stress. In addition, both enamel and dentine are involved in the restoration, although in some studies efforts are made to limit bonding to enamel (for example, in Van Dijken et al., Clinical long-term retention of etch-and-rinse and self-etch adhesive systems in non-carious cervical lesions. A 13 year evaluation. Dent Mat 2007).

The restoration is then re-assessed periodically. Obviously, loss of retention is considered, and sometimes restorations are also assessed on marginal integrity, marginal discolouring and aesthetics.

Whenever a restoration goes wrong, this is noted as a failure. The survival/lifetime of restorations is expressed in an Annual Failure Rate; for example, an AFR of 4.6 means that, on an annual basis, 4.6% of the restorations failed in the course of the study.

Phosphoric acid, sometimes also called orthophosphoric acid, is a substance that is used frequently in the practice of dentistry, mostly in concentrations between 30 and 40%. It is a proven substance for the etching of enamel (Buonocore 1955). It also entails hazards, because contact with the eyes and skin may cause severe irritation, blistering and burns.

The substance should only be applied where its use is intended, and proper control is of the essence. The use of a coloured gel is therefore recommended, preferably of a thixotropic type. The application of a cofferdam is also definitely recommended, and the patient should wear protective glasses ( the practitioners should obviously also wear protective glasses). When removing the etching gel, the main volume should first be sucked away using a saliva ejector without a cap. The area should then be rinsed clean with a spray mist suction device under continued suction.

If the etching gel should unintentionally get onto the skin or, even worse, into the eyes, the affected area should be rinsed with plenty of water until the patient no longer feels any pain in the affected area. In such a case, it is recommended that medical assistance be sought.

This article is based on a publication in the British Dental Journal Vol 217 No.2 Jul 25 2014
Link to the publication. 

I would like to refer to a recently conducted study by Garcia et al. to reply to this question, which derives from practice. The study examines the effect of three desensitisers on the bonding strength to dentine of a composite cement.

The study concluded that the effect is dependent on the material. Gluma Desensitizer (Heraeus Kulzer) and Super Seal (Phoenix Dental) decreased the bonding strength, whereas TeethmateTM Desensitizer (Kuraray Noritake) improved the bonding strength. The researchers obviously consider it necessary to conduct further research into the workings of TeethmateTM Desensitizer, a cement that contains calcium phosphate.

Clinical significance:

TeethmateTM Desensitizer, a material containing calcium phosphate, may serve as a useful new generation of desensitisers for use prior to the cementing of indirect restorations.

Click here for the research abstract.

Clinically proven

13 years of clinical evaluation show exceptional results for SE Bond.

The clinical effect of CSE in non-carious class V lesions remained excellent after 13 years. Selective etching on the enamel margins had only a limited positive effect on marginal integrity and absence of marginal colouring.

This is the conclusion of the study that was published last year:

A thirteen-year randomised, controlled clinical trial of a two-step self-etch adhesive in non-carious cervical lesions, by M. Peumans and colleagues from KU Leuven BIOMAT. Dental Materials 31 (2015) 308-314

This publication comprises the evaluation of the study after 13 years; the evaluations after 3, 5 and 8 years have already been published. NCCL’s (non-carious cervical lesions) are the most suitable treatments for the clinical testing of bond effectiveness. Only a limited number of studies with long-term results are available, and 13 years is the longest evaluation period to date.

So far, CSE is the only bonding to perform so well over such a long period of time.

Loss of retention is the most objective parameter in establishing the effectiveness of bonding in such a clinical test. The 13 year retention rate of CSE was high in this clinical test: no less than 96%!

In the course of this study, half the cavities were treated with CSE without the etching of the enamel margins with phosphoric acid; the other half were treated with selective etching of the enamel. Etching or non-etching of the enamel margins had no effect on the retention rate.

Interview med Dr. Matthias Gutweiler, administrerende direktør for Kuraray Europe GmbH

Små komponenter eller bestanddele kan have stor indflydelse på produkternes kvalitet. Ofte er der mindre kendte virksomheder skjult bag succesfulde mærker, og disse virksomheder sørger for produkternes præstationer takket være deres løsninger. Kuraray Europe GmbH med hovedsæde i Hattersheim am Main i Tyskland er en sådan producent, der skaber reel værdi for sine kunder med sine kemiske komponenter. Uanset om det drejer sig om maling, kondisko, glasruder eller tandplejeprodukter, bidrager de med materialer og komponenter, der fremstilles af datterselskabet til Kuraray Group fra Japan til at optimere mange af vores hverdagsting gennem deres innovative fysiske og kemiske egenskaber.

Fabrikanter af maling og lak, beklædning, køretøjer og tandlægeprodukter samt store papirkoncerner, arkitekter og mange andre er blevet afhængige af specialkemikalieproducentens kompetencer. ”Vi har en innovativ produktportefølje, er førende på mange områder og indtager attraktive nicher”, udtaler administrerende direktør Dr. Matthias Gutweiler om succesfaktorerne for Kuraray Europe. "Vi arbejder meget tæt sammen med vores kunder, og denne nærhed giver os en stor markedsfordel. "Vi har konstant fingeren på pulsen, hvad angår markedet, og vi er ekstremt hurtige og fleksible."

STOR PORTEFØLJE

Kuraray Europe er den førende producent af polyvinylalkohol i Europa, som bl.a. anvendes til vandopløselige dispersionsmalinger og træprimere og polyvinylbutyral (PVB), som er en plast, der f.eks. anvendes som folie i lamineret sikkerhedsglas. Derudover fremstiller virksomheden et bredt udvalg af andre produkter, lige fra termoplastiske elastomerer og flydende gummi over aktive kulfiltre og syntetiske fibre, til kunstlæder og tandplejeprodukter. SEPTONTMQ-elastomer kombinerer f.eks. gummis elastiske egenskaber med termoplastiske resiner og anvendes af kendte sportsskoproducenter til fremstilling af skosåler.

Med TROSIFOL® Sound Control har Kuraray udviklet en ny PVB-film med fremragende lydisolerende egenskaber. TirreninaTM er et kunstlæder, der fremstilles uden opløsningsmidler, og det er derfor den foretrukne løsning for miljøbevidste virksomheder.

"Ved hjælp af TROSIFOL® Sound Control har vi udviklet en ny PVB-film med fremragende lydisoleringsegenskaber", forklarer Dr. Matthias Gutweiler. "Sammenlignet med en glaskonstruktion med en standard PVB-folie er det muligt i samme struktur at opnå en forbedring af lydisoleringsværdierne på op til 3 dB ved hjælp af TROSIFOL® Sound Control." TROSIFOL®-film anvendes til fremstilling af sammensat laminat-sikkerhedsglas i køretøjer, bygninger eller solenergisystemer. TROSIFOL® findes blandt andet i glaskuplen i Berlins rigsdagsbygning, på YAS Hotel i Abu Dhabi og i glasgondolerne på London Eye, det store pariserhjul i London.

BERØMTE BYGNINGER

Overtagelsen af DuPont har yderligere udvidet vores produktportefølje med endnu flere innovative løsninger. Med SentryGlas® har virksomheden nu en kompositfilm som en del af sit produktsortiment. Denne film er hundrede gange stivere end PVB men har alligevel en forholdsvis tynd udformning, og den opfylder de strenge sikkerhedskrav, som kræves i moderne byggeri. SentryGlas® byder således på mange nye muligheder og designfrihed samt god æstetik og funktionalitet, f.eks. i facader, faldskærme, glasgulve eller trapper. Produktet er f.eks. blevet brugt til renovering af første etage i Eiffeltårnet. SentryGlas® er også blevet anvendt i kombination med silikoner fra Dow Corning til Louis Vuitton-bygningen i Frankrig, hvis buede glasflader strækker sig som skibssejl over trætoppene på Paris Bois de Boulogne.

NYE PROJEKTER

Kurarays afdeling for forskning- og udvikling spiller en stor rolle for vores virksomhed, som konstant arbejder på nye projekter med at udvikle nye løsninger til sine kunder. "I dag er kemikalievirksomheder løsningsleverandører, der hjælper kunderne med at generere værdier", siger den administrerende direktør. "Det handler ikke længere kun om at sælge produkter, men snarere om effektivitetsforbedring og samarbejdsmæssige innovationer. Her fokuserer vi på direkte kundekontakt for at vi gennem dialog med kunden kan finde frem til, hvordan vi kan hjælpe". Kuraray har forpligtet sig til en permanent investering i sin afdeling for forskning og udvikling (R&D) for at udvikle teknologier, der skaber konkurrencefordele, samtidig med at de skaber værdi for kunden. I dag er koncernen blevet en international markedsleder inden for innovative højtydende materialer.

UNIKKE PRODUKTER

Kuraray blev grundlagt i 1926 i Japan med en aktiv verdensomspændende tilstedeværelse, mens Kuraray Europe GmbH har eksisteret siden 1991. "Vi ønsker at vokse yderligere og fremstille produkter, der er så unikke, at de ikke kan kopieres", siger Dr. Matthias Gutweiler. "Vores løsninger skal fortsætte med at bidrage til at gøre hverdagen lidt bedre".

Med TROSIFOL® Sound Control har Kuraray udviklet en ny PVB-film med fremragende lydisolerende egenskaber.

Mowiflex C 30 er et vandopløseligt støttemateriale, f.eks. til 3D-printing