Aliphatic, hydroxyfunctional polycarbonate ester-polyurethane dispersion.Binder for water-reducible 2K-PUR coatings, especially soft-touch and comfort coatings.
Product description
Applications
Bayhydrol® U 2757 can be used in combination with flexible polyurethane dispersions, e.g. Bayhydrol® UH 340/1, UH 650, UH 2305 and UH XP 2660 to formulate soft-touch coatings. In combination with polyacrylates, e.g. Bayhydrol® A 2058 highly chemical resistant comfort coatings can be formulated. Suitable polyisocyanate components are e.g. Bayhydur® 3100, 304, XP 2655 and also Desmodur® N 3600 and N 3900.
Form supplied
approx. 52 % in water / DMEA
Specification
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Viscosity | at 23 °C,(D = approx. 40 s^(-1) | 300 - 1,500 | mPa*s | DIN EN ISO 3219/A.3 |
| Non-volatile content | (1 g / 1 h / 125 °C) | 50,0 - 54,0 | % | DIN EN ISO 3251 |
| pH-value | 7,0 - 8,0 | DIN ISO 976 |
Typical Values
| Property | Test Condition | Value | Unit | Standard |
|---|---|---|---|---|
| Acid number | approx. 9 | mg KOH/g | DIN EN ISO 2114 | |
| Density | at 20 °C | approx. 1,07 | g/ml | DIN EN ISO 2811 |
| OH content (solid resin) | approx. 1,9 | % | ||
| Minimum film forming temperature (MFT) | < 0 | °C | DIN ISO 2115 |
Storage
- Storage in original sealed Covestro container. - Recommended storage temperature: 5 - 30 °C. - Protect from frost , heat and foreign material. General information: The product should be protected against frost.
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.
Processing
Sand and bead mills have proved suitable as grinding equipment. During grinding, the temperature of the mill base should not exceed 40 °C. The pH of coating systems based on Bayhydrol® U 2757 is between approx. 6.0 and 8.0 after formulation. The coatings can be applied using conventional spraying techniques. Depending on the application, drying conditions are 30 - 45 min at 80 °C.
After use, formulation and application equipment should be cleaned immediately or left to soak in water. Warm water, alkaline cleaning agents or alkaline isopropyl alcohol are suitable for cleaning.
Health and Safety Information
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.
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 .
