Before working with this product, you must read and become familiar with the available information on its risks, proper use, and handling. Information is available in several forms, e.g., in particular in the currently valid safety data sheets and product labels. For further information contact your Covestro representative.
Product description
Hydrophilic aliphatic polyisocyanate based on hexamethylene diisocyanate (HDI).Hardener for waterborne two-component polyurethane systems.
Applications
Bayhydur® ultra 307 is a crosslinking agent for waterborne systems from which reliable incorporation and high chemical resistances are required. Despite its relatively low hydrophilia, this hardener can be easily dispersed in the aqueous phase, even at low shear forces such as are typically found in trade applications. Coatings formulated with the product yield films with high gloss and very low haze. The increase in viscosity during mixing that is typical for hydrophilized hardeners, in particular with ionically hydrophilized polyol dispersions, can be controlled by prethinning with water or slight amounts of organic cosolvent.The dispersibility of the product in water is influenced by organic cosolvents, but in different ways. The use of highly hydrophobic or highly hydrophilic cosolvents such as butyl acetate, xylene, butyl glycol acetate, dimethyl formamide or N-methylpyrrolidone generally leads to a coarser dispersion, which may cause turbidity in the coating film depending on the entire system. On the other hand, the use of, for example, methyl ethyl ketone, methoxypropyl acetate, dipropylene glycol dimethyl ether, propylene glycol diacetate or dicarboxylic acid diester mixtures leads to fine-particle dispersions.Because of the balance between moderate hydrophilization and high functionality, waterborne two-component polyurethane coatings formulated with Bayhydur® ultra 307 exhibit fast drying, rapid hardening with high ultimate hardness and excellent chemical resistance of the resultant films. Bayhydur® ultra 307 can be used as the crosslinking partner for waterborne polyol binders (Bayhydrol®) and as a crosslinker for largely pH-neutral waterborne polymer dispersions such as polyurethane, polyvinyl acetate, polyacrylate and synthetic rubber dispersions.After addition of Bayhydur® ultra 307, the ready-to-use two-component formulation must be used within the pot life. This is not only governed by the polymer content but also by its other constituents (resin, thickener, plasticizer, etc.). With many dispersions, the end of this pot life – usually several hours – is not marked by gelling.
Specification
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Viscosity | at 23 °C | approx. 6,000 | mPa*s | M014-ISO 3219/A.3 |
| NCO content | approx. 20,3 | % | M105-ISO 11909 | |
| Hazen color value | ≤ 60 | M017-EN 1557 | ||
| Monomeric HDI | < 0,10 | % | M106-ISO 10283 |
Typical Values
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Flash point | approx. 211 | °C | DIN EN ISO 2719 | |
| Density | at 20 °C | approx. 1,16 | g/cm3 | DIN EN 2811 |
Solubility / thinnability
The product is generally compatible with organic solvents such as esters or ethers. However, solubility and compatibility should be tested in each case.Regarding the influence of the solvent (cosolvent) on the emulsibility of the polyisocyanate, please refer to the information in the section "Properties/applications". Only PU grade solvents should be used (< 0.05 % water).
Storage
- Storage in original sealed Covestro container. - Recommended storage temperature: 0 - 30 °C. - Protect from moisture, heat and foreign material. General information: Hydrophilic isocyanates are very moisture-sensitive and react with water to form carbon dioxide and insoluble ureas. The containers must always be kept tightly closed. The access of water in all forms (moist air, solvents, moist containers) must be prevented, because the generation of carbon dioxide can lead to dangerous increases in pressure. Storage at higher temperatures will result in increase of color and viscosity.
Storage time
Covestro represents that, for a period of six months following the day of shipment as stated in the respective transport documents, the product will meet the specifications or values set forth in section "specifications or characteristic data" above, what ever is applicable, provided that the product is stored in full compliance with the storage conditions set forth in and referenced under section "storage" above and is otherwise handled appropriately.The lapse of the six months period does not necessarily mean that the product no longer meets specifications or the set values. However, prior to using said product, Covestro recommends to test such a product if it still meets the specifications or the set values. Covestro does not make any representation regarding the product after the lapse of the six months period and Covestro shall not be responsible or liable in any way for the product failing to meet specifications or the set values after the lapse of the six months period.
Health and Safety Information
Disclaimer
General
The manner in which you use our products, technical assistance and information (whether verbal, written or by way of production evaluations), including any suggested formulations and recommendations, are beyond our control. Therefore, it is imperative that you test our products to determine suitability for your processing and intended uses. Your analysis must at least include testing to determine suitability from a technical, health, safety, and environmental and regulatory standpoint. Such testing has not necessarily been done by Covestro, and Covestro has not obtained any approvals or licenses for a particular use or application of the product.
Unless we otherwise agree in writing, all products are sold strictly pursuant to the terms of our standard conditions of sale which are available upon request.
All information and including technical assistance is given without warranty or guarantee and is subject to change without notice. It is expressly understood and agreed by you that you assume and hereby expressly release indemnify us and hold us harmless from all liability, in tort, contract or otherwise, incurred in connection with the use of our products, technical assistance, and information. Any statement or recommendation not contained herein is unauthorized and shall not bind us. Nothing herein shall be construed as a recommendation to use any product in conflict with any claim of any patent relative to any material or its use. No license is implied or in fact granted under the claims of any patent.
Non Medical and non Food Contact
This product is not designated for the manufacture of a medical device or of intermediate products for medical devices (1). This product is also not designated for other specifically regulated applications (e.g. including cosmetics, plant protection, fertilisers, plant strengtheners, food processing, food contact and others). If the intended use of the product is for the manufacture of a medical device or of intermediate products for medical devices or for other specifically regulated applications Covestro must be contacted in advance to provide its agreement to sell such product for such purpose. Nonetheless, any determination as to whether a product is appropriate for use in a medical device or intermediate products for medical devices, for Food Contact products or cosmetic applications must be made solely by the purchaser of the product without relying upon any representations by Covestro.
1) Please see the Guidance on Use of Covestro Products in a Medical Application document.
Sample
Any samples provided by Covestro are for testing purposes only and not for commercial use.
Typical value
These values are typical values only. Unless explicitly agreed in written form, they do not constitute a binding material specification or warranted values
Contact
Please use our contact form or contact us directly by sending an e-mail to technical-datasheets@cx.covestro.com .
