Pigmented Isocyanate Formulations With Stable Storage Viscosity

Solution Overview

Problem

Existing formulations containing isocyanate groups are not storage-stable and exhibit significant viscosity increase over time, which affects their usability in applications like digital printing.

Innovation Solution

A formulation comprising pigments, isocyanate group-containing components, wetting agents, dispersants, and grinding resins, with a controlled molar ratio of isocyanate groups, maintains a viscosity rise of less than 500% after storage at 50°C for at least 3 days, ensuring stability and redispersibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If isocyanate group-containing formulations are prepared with pigments and reactive components, then reactivity and processing capability are improved, but storage stability deteriorates due to significant viscosity increase over time

Engineering Contradiction:

ImprovereactivityVSAvoidstorage stability

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent applies preliminary action by pre-modifying the pigment surface with isocyanate groups before formulating the final composition. This preliminary modification creates a stable pigment core that prevents unwanted reactions during storage, while still maintaining reactivity for subsequent processing steps. The pigment is pre-treated with isocyanate-containing compounds to create a stable intermediate state.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses an intermediary approach by introducing a coupling agent or surface-modified pigment as a mediator between the isocyanate groups and the pigment particles. This intermediary structure allows the formulation to remain stable during storage while enabling controlled reactivity during processing. The coupling agent acts as a buffer that prevents direct unwanted reactions.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If isocyanate groups are present in the formulation during processing, then reaction capability is improved, but pigment flocculation and sedimentation occur during storage

Engineering Contradiction:

Improvereaction capabilityVSAvoidformulation uniformity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by pre-modifying the pigment surface with isocyanate groups before formulating the final composition. This preliminary modification creates a stable pigment core that prevents unwanted reactions during storage, while still maintaining reactivity for subsequent processing steps. The pigment is pre-treated with isocyanate-containing compounds to create a stable intermediate state.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses parameter changes by carefully controlling the ratio of isocyanate groups to hydroxyl groups, adjusting the concentration of reactive components, and optimizing the formulation composition to maintain a balance between reactivity and stability. By adjusting these parameters, the formulation remains stable during storage while retaining sufficient reactivity for processing.

Inventive Principle:

Principle #35Parameter changes

3Ease of operation

If the formulation contains reactive isocyanate groups, then processing flexibility is improved, but viscosity increases significantly over storage time

Engineering Contradiction:

Improveprocessing flexibilityVSAvoidshelf life

Core Design Contradiction:

Ease of operationVSDuration of action of stationary object

Solution Approach 1:

The patent applies preliminary action by pre-modifying the pigment surface with isocyanate groups before formulating the final composition. This preliminary modification creates a stable pigment core that prevents unwanted reactions during storage, while still maintaining reactivity for subsequent processing steps. The pigment is pre-treated with isocyanate-containing compounds to create a stable intermediate state.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses parameter changes by carefully controlling the ratio of isocyanate groups to hydroxyl groups, adjusting the concentration of reactive components, and optimizing the formulation composition to maintain a balance between reactivity and stability. By adjusting these parameters, the formulation remains stable during storage while retaining sufficient reactivity for processing.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12570864B2Storage-stable pigmented formulations containing isocyanate groups and use thereof

Publication Date: 2026.03.10 COVESTRO DEUTSCHLAND AG

AI summary

The invention relates to storage-stable pigmented formulations containing isocyanate groups, comprising at least one pigment a., at least one component b. containing isocyanate groups, at least one wetting agent and/or dispersant c., at least one grind resin d. and optionally solvents, wherein the formulation has a viscosity increase of less than 500% after storage at 50° C. over a period of at least 3 days. The invention also relates to the production of such formulations and to the use thereof.