Covestro Bayhydrol U 2757 polycarbonate-based polyurethane dispersion

Products Features
Aliphatic hydroxyl-functional polycarbonate polyurethane dispersion (without co-solvent), which can be used as a binder for the preparation of waterborne two-component polyurethane coatings, especially soft-touch coatings
Supply Form
About 52% in aqueous solution/dimethylethanolamine

Specifications
Property             Value           Unit           Test Method
Viscosity@23°C 300-1500 mPa·s DIN EN ISO 3219/A.3
(D=40s-1)
Non-volatile content 50.0-54.0 % % EN ISO 3251
(1g/1h/125°C)
pH 7.2-8.2                                                                                 (1:4 diluted in deionized water)

special Performance
• No co-solvent
• Excellent flexibility
• Good chemical resistance
• Good scratch resistance
• Suitable for making flexible coatings with excellent tactile feel

Other Data*
Property             Value           Unit           Test Method
Acid Value Approx. 9 mg KOH/g DIN EN ISO 2114
Density@20°C Approx. 1.07 g/ml DIN EN ISO 2811
OH content about 1.0 % %
Minimum Film Forming Temperature <0       °C         DIN ISO 2115
(MFT)
*This data is general information and is not part of the product specification.

Features /app
Bayhydrol® U XP 2757 can be combined with flexible polyurethane dispersions (e.g. Bayhydrol® UH 340/1, UH 650, UH 2305 and UH XP 2660) to produce soft-touch coating. Can be combined with polyacrylates such as Bayhydrol® A2058 to produce coatings with excellent chemical resistance. Suitable polyisocyanate components include: Bayhydur® 3100, 304, XP2655 and Desmodur® N3600 and N3900.

Cleaning
Clean or soak coating and dispensing equipment in water immediately after use. Cleaning can be done with warm water, alkaline cleaners or alkaline isopropyl alcohol etc.

Processing
A sand mill has proven to be a suitable grinding device. During the grinding process, the temperature of the grinder base should not exceed 40°C. The pH range of coating systems made with Bayhydrol® U XP 2757 is approximately 6.0 to 8.0. Can be applied by conventional spraying method. The drying condition is 30-45 minutes at 80°C, depending on the specific construction conditions.

Save
- Store in original Covestro airtight container.
- Recommended storage temperature: 5-30℃
- Avoid frost, heat andforeign matter.
General Information: Freeze should be avoided.

Save Time
The manufacturer declares that, under the condition that the product is stored in full compliance with the requirements of the above "storage" clause and handled properly, the product will be transported within 6 days from the date of transportation stated on the transportation document Compliance with the specifications or characteristic values ​​described in the "Specification or characteristic values" clause above, as applicable, during the month. If the product exceeds the above-mentioned 6-month period, it does not mean that it no longer meets the set values ​​in the specifications or characteristic values. However, the manufacturer recommends that products older than 6 months from the date of shipment be tested before use to confirm that they still comply with the values ​​set forth in the specification or characteristic values. The manufacturer does not make any promises for products that have been shipped more than 6 months from the date of shipment, and does not assume any responsibility and liability for non-compliance with specifications or set values ​​​​in the characteristic values.

Security
This product data sheet applies only to the latest version of the corresponding safety document. Any updates to safety-related information consistent with legal requirements will only be reflected in the Safety Data Sheet, which will be updated and published. Information on current classification and labelling, application and process methods, and further safety data can be found on the latest valid safety data sheet.