Covestro certifies that the product meets its specifications until the expiry date stated on the Certificate of Analysis, provided it has been stored and handled in accordance with Covestro’s specified conditions. Unless otherwise indicated, the expiry date is 6 months after quality control release. After expiry, product performance is not assured; customers are responsible for retesting material before use. Covestro makes no representations and assumes no liability for the product after the expiry date.
Product description
Desmodur® Z 4470 SN/BA is an aliphatic polyisocyanate based on isophorone diisocyanate (IPDI) and dissolved Aromatic 100 and n-butyl acetate (2:1).
Applications
Desmodur® Z 4470 SN/BA differs from conventional types of aliphatic polyisocyanates by having better solubility/dilutability in mild solvents (aromatics, aliphatics) as well as better compatibility with air-drying alkyd resins. Desmodur® Z 4470 SN/BA polyisocyanate is mainly used as an “additive resin” in existing, ready-for-use coating formulations to accelerate their drying, curing, and chemical crosslinking to obtain shorter dry, tape, and recoat times, and improved hardness and gasoline resistance in cured films.
When Desmodur® Z 4470 SN/BA is used as an additional drying and curing component in air-drying alkyd coatings, NCO/OH ratios of less than 0.5/1.0 are usually sufficient. With some types of alkyd resins, higher additions of Desmodur® Z 4470 SN/BA polyisocyanate will cause embrittlement. The best level of addition should be determined in each case.
Weathering of films containing Desmodur® Z 4470 SN/BA polyisocyanate is mostly dependent on the type of alkyd resin used. The slight yellowing of alkyd resins modified with unsaturated fatty acids is slightly increased by the polyisocyanate addition. This tendency to yellow is more pronounced at drying temperatures above 176°F (80°C). It is recommended that forced drying be carried out below 176°F (80°C).
Combining Desmodur® Z 4470 SN/BA polyisocyanate with flexible polyesters and acrylics or properly formulated polyester/acrylic blends yields two-component polyurethane coatings with outstanding weather resistance. Adding Desmodur® Z 4470 SN/BA polyisocyanate limits the potlife of the coating material. The potlife is approximately 8 hours for coating materials adjusted to spray viscosity. The potlife is influenced by the ingredients used in the formulation of the coating.
As with any product, use of Desmodur® Z 4470 SN/BA polyisocyanate in a given application must be tested (including but not limited to field testing) in advance by the user to determine suitability.
Specification
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Non-volatile content | 68.0 - 72.0 | % | M001 | |
| NCO content | 11.5 - 12.3 | % | M105 - ISO 11909 | |
| Monomer content | < 0.35 | % | M106 - ISO 10283 | |
| Dynamic viscosity | 25 °C | 700 - 1,300 | mPa·s | M014 - ISO 3219/A.3 |
| Color | Hazen | ≤ 60 | M017 - EN 1557 |
Typical Values
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Color | colourless to yellowish | |||
| Flash point | 46 | °C | DIN 53213 |
Solubility / thinnability
Desmodur® Z 4470 SN/BA polyisocyanate is completely soluble in, or reducible with, aromatic solvents, even in the absence of polar solvents such as esters, ketones, or ether esters. It is possible to formulate solutions with a minimum solids content of 20% that have good storage stability using aromatic solvents. Stability must be checked in the particular solvent mixture used. Aliphatic solvents should not be used for dilutions. However, Desmodur® Z 4470 SN/BA polyisocyanate has enough compatibility with aliphatic solvents that it can be added to most aliphatic solvent-based coatings. Water-containing solvents and solvents such as alcohols should not be used. Desmodur® Z 4470 SN/BA reacts with these materials, causing undesirable side effects.
Compatibility
Desmodur® Z 4470 SN/BA polyisocyanate has good compatibility with Desmodur N and Desmodur L polyisocyanates. It can be combined with many alkyd resins, as well many Desmophen® polyesters and acrylics. Desmodur® Z 4470 SN/BA is also compatible with vinyl copolymer resins and with some nitrocellulose and low molecular weight epoxy resins. Compatibility with cellulose acetate butyrate resins is limited.
Storage
Desmodur® Z 4470 SN/BA stored in tightly sealed original containers and protected from heat, moisture, and foreign materials.
Storage time
Health and Safety Information
Before working with this product, you must read and become familiar with the available information regarding its risks, proper use, and safe handling. This information is provided in various formats, including the current Safety Data Sheet (SDS) and product label. SDS can be accessed via the following link:
Safety Data Sheets (SDS) for Covestro products | Covestro
For further questions, please use the contact information provided on this technical data sheet.
Important
Desmodur® and Desmophen® are registered trademarks of the Covestro Group.
Disclaimer
Responsibility and Liability
The use of Covestro products, technical assistance, and information (regardless of how provided) is outside Covestro’s control and is solely the responsibility of the customer. The customer must conduct adequate testing to determine the suitability of products for its intended use, including but not limited to technical, health, safety, and environmental aspects. Unless otherwise agreed in writing, all products are sold exclusively under Covestro’s standard conditions of sale, which prevail in case of conflict and are available upon request.
The terms and conditions of sale and delivery are available via the following link:
https://order.covestro.com/covestrostorefront/saleConditions
All information is provided “as is” without warranties, express or implied, including merchantability or fitness for a particular purpose, and is subject to change without notice. To the maximum extent permitted by law, Covestro disclaims, and the customer assumes all liability for losses, damages, or claims arising out of use of Covestro products, technical assistance, or information. Any statement or recommendation not expressly contained in Covestro documentation is unauthorized and shall not bind Covestro. Nothing herein shall be construed as encouraging or recommending the use of any product in conflict with any claim of any patent. No license is implied or in fact granted under the claims of any patent.
Restrictions on Regulated Applications
This product is not intended for use in regulated applications such as agriculture, cosmetics, drinking water contact, food contact, medical products (e.g., medical devices), toys, or similar uses subject to specific regulatory requirements. Prior written approval from Covestro is required before this product may be used in any regulated application. The customer is solely responsible for ensuring compliance with all applicable laws and determining product suitability. Covestro disclaims all liability and warranties for unauthorized regulated uses.
Typical Value
The values provided are typical only and do not represent binding specifications. Unless expressly confirmed in a written contract, these values are not part of the contractual quality agreement and must not be relied upon as a warranty or guarantee of product performance.
Sample
Samples provided by Covestro are intended solely for evaluation and testing purposes by the customer and may not be used in commercial applications, resold, transferred to third parties (except qualified testing service providers acting on behalf of the customer), reverse engineered, modified, or used in any manner not explicitly authorized in writing by Covestro. Samples are provided ‘as-is’ without any warranties, express or implied, including fitness for a particular purpose. Customers are solely responsible for ensuring safe handling, regulatory compliance, and suitability of the material for their intended evaluations. Covestro disclaims all liability for damages or losses arising from the use of samples.
Contact Information
Please use our contact form or contact us directly by sending an e-mail to technical-datasheets@cx.covestro.com .
