Optical Brighteners

Blankophor®:
Optical Brighteners

Special polymers used to adjust rheology, optical appearance, viscosity, or electrical conductivity.

Over the last 70 years, optical brighteners (OBAs) have played an indispensable role in increasing whiteness and brightness in papers. The mechanism is based, in very simplified terms, on absorbing UV light that is not visible to humans and re-emitting it in the visible range. This effect is called fluorescence.

The INDULOR optical brighteners can be broadly divided into four product groups:

• Standard Tetrasulfo
• Disulfo
• Hexasulfo
• Advanced Tetrasulfo

Each of these four product groups has been developed for specific application scenarios and has its own strengths and weaknesses. Thus, INDULOR can offer the best solution for each of the typical paper applications (mass, surface, and coating).

The first Blankophor OBAs were developed in the R&D laboratories of Bayer AG in Leverkusen and introduced to the market under the BLANKOPHOR® brand in the 1940s. Since then, BLANKOPHOR products have been distinguished by their high quality in terms of performance and environmental compatibility.

Eco-label: All BLANKOPHOR® brighteners are compliant with the EU Ecolabel and the Nordic Ecolabel ("Nordic Swan"). Some of the BLANKOPHOR® brighteners also meet the criteria of the German Blue Angel eco-label.

Food contact: All BLANKOPHOR® brighteners are approved according to the 36th recommendation of the BfR (Food Contact Germany).

They are also compliant with the EU regulations EC 1935/2004 (food contact materials) and EC 2023/2006 (good manufacturing practice for food contact materials). Some of our brighteners are also FDA approved. (Food Contact USA).

As part of our technical service, we offer the development of cost optimized whitening concepts for our customers. Due to our extensive possibilities in our laboratories as well as years of know-how in the application of our products, we are able to develop successful and efficient solutions for whitening concepts.

In doing so, we do not limit ourselves to the use of our whiteners. A wide variety of fiber and filler qualities as well as different nuance possibilities are taken into account. As a result, we develop models that serve as a reliable basis for machine trials.

On our pilot paper machine, concept papers can be produced that are specially tailored to customer requirements, which can then be further refined in the application technology laboratory. The possibilities are therefore extensive.

Our Application Technology department is also available for internal and external training courses in the field of brighteners.

In addition to the main area of application in the paper industry, some of our products can be used for the following applications:

• Adhesives
• Photo industry
• Textile
• Cleaning Agents or Detergents
• Paints and Lacquers
• Medical Diagnostics
• Leak Testing of Engines and Equipment

Optical brighteners in the paper industry

Our optical brighteners are mainly used in the paper industry, where they are used for paper production or finishing. Typical applications in the paper industry are in paper pulp, film, size press and pigmented coating.

Optical Brighteners in the Adhesives industry

BLANKOPHOR® products are ideally used as fluorescent sizing additives to starch-based sizing formulations. The whitener serves as a fluorescent marker that makes the applied glue visible under UV light. This makes it much easier to assess, monitor, and automatically detect the glue application.

We offer products for both water-based and solvent-based adhesives.
 

Optical Brighteners in the Photo industry

In the photo industry, our optical brightener is used as a special additive (whitener) in color photography.

BLANKOPHOR® FCD liq. is an additive for use in color photography developer solutions with the following effects:

• Improvement of black and white intensities on the developed photo
• Suppression of yellowing
• Stabilization of the black tint

BLANKOPHOR® FCD liq. supports the sustainability of an intense and neutral black and white.

Optical brighteners in the Textile industry

Optical brighteners are used in various textile applications.

Optical brighteners for the Paint and Coatings industry

BLANKOPHOR® products are excellent for water-based interior paints to increase the whiteness and bluish tint of the paint.

This allows for more cost-efficient pigment blends in the formulation and improves cost performance tremendously.

Advantages:

• Savings on titanium dioxide
• Use of anatase instead of rutile
• Use of yellowish chalk types (GCC) instead of marble
• Enhancement of whiteness in standard formulations

A range of specialized BLANKOPHOR® formulations are available for this application.

Printing inks

BLANKOPHOR® products can be used in printing inks for the following purposes:

• as a fluorescent marker (instead of an indicator spray)
• to improve the contrast of the print

Optical brighteners for Cleaning and Washing Agents

• Optical brighteners are commonly used in heavy-duty detergents.

Medical diagnostics

Optical brighteners are widely used in medical diagnostics:

• Staining of native preparations
• Fluorescent staining of fungi
• Detection of fungal mycelium, pseudomycelium and yeast cells
• brightening of dermatomycosis or onychomycosis (skin fungus, nail fungus) as well as
• in the mycological laboratory

Optical brightener for Quality Control

Our optical brighteners are also used as (fluorescent) markers for detecting leaks of engines, machines, and equipment in the automotive, aerospace and aviation industries.