Preparing to Paint or Bond? Choosing the Right IPA Wipe Concentration
Successful surface preparation starts well before the paint is sprayed or the adhesive is applied. The condition of the surface, the contamination present and the cleaning method all influence the next stage of the process.
Isopropyl alcohol—commonly known as IPA—is widely used in industrial surface preparation. But specifying an “IPA wipe” is only part of the picture. The concentration, wiping material and amount of liquid delivered all need to suit the application.
At Speciality Wipes, we supply standard IPA concentrations of 30%, 60%, 70%, 85%, 90%, 96% and 100%. Our customers use this range across different processes, particularly when preparing surfaces for spraying and adhesive application.
So, how do you choose?
Start with the process specification
The first question should be: what does the paint, adhesive or component manufacturer recommend?
An established process may specify a particular cleaner, IPA concentration, wiping method or drying interval. These requirements should guide product selection.
A higher IPA percentage should not automatically be treated as an upgrade. Changing the cleaning formulation can change how the preparation stage behaves, so any proposed alternative should be evaluated before it is introduced into production.
Where no cleaning specification exists, the starting point is to understand the surface, the contamination and the finish or bond required.
Higher concentration does not automatically mean better preparation
It is easy to assume that 100% IPA must provide the best result because it contains the most alcohol. Surface preparation is more specific than that.
IPA and water blends are established cleaning options in some adhesive processes. For example, 3M’s guidance for many VHB™ tape applications recommends an IPA and water mixture, with additional preparation needed for certain substrates and contaminants. That recommendation applies to those applications; it is not a universal formula for every adhesive or coating. [1]
The practical lesson is straightforward: choose the formulation that suits the validated process, rather than selecting by percentage alone.
Our standard range gives customers options when developing a new preparation method or sourcing wipes to an existing specification.
Identify what needs to be removed
A surface can look clean while still carrying contamination that matters to the next operation.
Handling marks, light oils, machining residues, dust and release agents present different cleaning challenges. Before selecting a wipe, it helps to establish where the contamination comes from and what the cleaning stage must remove.
IPA should not be assumed to remove every contaminant effectively. Heavy oils or grease, for example, may require a separate, suitable cleaning stage before a final IPA wipe in an approved bonding process. [1]
Increasing the IPA concentration is therefore not a substitute for understanding the contamination.
Consider the surface as well as the cleaner
The preparation method must also be suitable for the material being cleaned.
Metals, plastics, composites and existing painted finishes can have different compatibility requirements. A cleaning process approved for one component should not automatically be transferred to another.
For spraying applications, follow the coating supplier’s preparation instructions, including any requirements for degreasing, abrasion and final cleaning. For adhesive applications, check whether a primer, activator or other treatment is required.
An IPA cleaning wipe should only perform the role assigned to it within that process.
The wiping material matters too
The liquid is only one part of a presaturated wipe. The cloth must be appropriate for the surface and task, with consideration given to:
- Low-lint performance
- Strength during use
- Absorbency and liquid delivery
- Wipe size and coverage
- Compatibility with the cleaning formulation
Liquid loading also matters. The wipe needs to deliver an appropriate amount of cleaner for the intended operation, supported by a defined wiping method and any required drying stage.
Selecting the concentration, fabric and saturation together creates a more useful specification than requesting an IPA percentage alone.
Make the preparation stage repeatable
Once a suitable process has been established, consistency becomes the priority.
Presaturated wipes allow the specified cleaning formulation and wiping material to be supplied together in a ready-to-use format. Packaging can then be selected around how the product will be used—from individual sachets for defined tasks to tubs, pouches or buckets for repeated operations.
Operators should follow the approved procedure, replace contaminated wipes as required and keep packs correctly closed between uses.
A wipe specified around your application
At Speciality Wipes, we help customers select IPA wipes around their surface preparation requirements.
With standard concentrations of 30%, 60%, 70%, 85%, 90%, 96% and 100%, alongside a choice of wiping materials and packaging formats, we can support both existing specifications and new product evaluations.