Hoechst Aktiengesellschaft

Clariant Corporation

Karl Gaa

Gerhard Pfahler

Matthias Z Ah

Mathias Mehrer

Alexander Lichtblau

Georg Schmailzl

Josef Wiedemann

Matthias Z&auml;h

Thomas St&auml;hrfeldt

Thomas Stahrfeldt

Klaus Keck-Antoine

G&uuml;nter Nowy

G Unter Nowy

Storage-stable plastics additives

Oligomeric stabilizer mixture

The present invention relates to novel UV stabilizers of the formula (I) ##STR1## where the substituents are as defined in the description. These compounds are highly suitable for stabilizing organic material, such as plastics, surface coatings, paints and oils, against the action of light, radiation, oxygen and heat.

Light stabilizers based on sterically hindered amines

The present invention relates to plastics comprising a high molecular weight, sterically hindered amine, wherein the sterically hindered amine is at least one amine from the group consisting of I: oligomerized 2,2,4,4-tetramethyl-20(oxiranylmethyl)-7-oxa-3,20-diazadispiro�5.1.11.2!he neicosan-21-one, II: condensation product of 2-chloro-4,6-di(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triaz ine and 1,2-bis(3-aminopropylamino)ethane, and III: condensation product of 1-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid. These plastics exhibit a reduced rate of uptake of sulfur compounds. The invention further relates to shaped articles made from these plastics.

Plastic with reduced sulfur uptake rate

Polyalkylpiperidine compounds of the formula I ##STR1## in which Y is the group ##STR2## are very effective stabilizers for organic materials.

Polyalkylpiperidine compounds

The invention relates to a process for the preparation of polyalkyl-1-oxa-diazaspirodecane compounds, which can be used as highly active light stabilizers for polymers. The reaction is carried out in a solvent mixture of at least one alcohol and if appropriate an inert organic solvent in the presence of solid alkali metal hydroxide or a corresponding amount of a mixture of solid alkali metal hydroxide and water as the sole catalyst. The process offers the advantage that, by using a solvent mixture and dispensing with a phase transfer catalyst, a higher rate of reaction and therefore higher product quality with the same yield are achieved. By dispensing with a phase transfer catalyst, which remains in the waste water and must be disposed of expensively, and by the reusability of the solvent mixture, the process is more environment-friendly and more economical than processes known to date.

Process for the preparation of polyalkyl-1-oxa-diazaspirodecane compounds

Polyalkylpiperidine compounds of the formula I ##STR1## in which Y is one of the groups ##STR2## are distinguished by very low volatility at elevated temperature and are very effective stabilizers for organic substances.

The invention relates to a process for the preparation of polyalkyl-1-oxa-diazaspirodecane compounds, which can be used as highly active light stabilizers for polymers. The reaction is carried out in an inert organic solvent in the presence of solid alkali metal hydroxide or of the corresponding amount of a mixture of solid alkali metal hydroxide and water as the sole catalyst. The process offers the advantage that, by changing the reaction procedure in a multiphase system and avoiding the use of a phase transfer catalyst, equally good results are achieved with regard to product quality and yield. Additionally, it is possible to reduce the reaction time from over 6 hours to 30 minutes. This results in a considerable rise in the space-time yield and consequently contributes, in addition, to an increase in the economy of the process of the invention.

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Burtenbach, Germany

Karl Gaa