Painting PVC profiles for plastic windows

Sometimes the white color of PVC window frames is no longer suitable. PVC profiles are installed for many decades, their durability is beyond doubt, but their appearance may deteriorate when exposed to an aggressive atmosphere. Therefore, the question arises: is it possible to paint plastic windows yourself at home? The answer to this question is unequivocally - yes, it is possible. Let's figure out what and how.

Painting PVC profiles for plastic windows

The surface of the PVC profile or plastic windows to be painted must be clean and dry, and there must be no glue or silicone residues on it.
Immediately before painting PVC, it is necessary to clean the profile from dust and residual plastic chips and shavings with compressed air, remove the protective film, and protect parts of the profile that are not to be painted with adhesive masking tape. Using a rag soaked in a special cleaner for PVC, degrease and clean the PVC profile from dirt and glue residues, which also removes static tension. Before you start painting PVC windows with water-based paint for PVC, you need to wait for the time (1–2 minutes) necessary for the cleaner to evaporate from the surface of the profile.

At least one hour before the start of painting plastic windows, the paint is tinted to the required shade. Check the viscosity using a VZ-6 viscometer and, if necessary, adjust it by adding purified water - recommended values: 25-30 seconds. Before use, the paint should be filtered (filter 100-200 microns).

Reasons for repainting windows

Windows made of polyvinyl chloride profiles are rarely touched upon during cosmetic renovations of buildings. But in some cases it is necessary to paint them too. This happens in the following situations:

• the coating turned gray;
• the plastic has turned yellow;
• scratches and other defects have appeared that cannot be washed off or cleaned out;
• the interior changes, and the snow-white color of the frames becomes inappropriate;
• I had a desire to make my windows original, not like everyone else’s.

Manufacturers of PVC windows do not prohibit painting their products. Professional painting of plastic windows in various colors is often done using the lamination method - when a special laminating film is applied to the plastic. This can only be done by specialists with professional equipment. After this treatment, the windows receive, in addition to the new color, additional protection from ultraviolet radiation, high and low temperatures, aggressive chemicals, and precipitation. Another technology for processing window frames is spraying a layer of polyurethane enamel. Recently, window manufacturers, at the request of the client, paint polyvinyl chloride not in white, but with brown wood-like paint. But even the structure of this PVC is different. If the windows are already standing, then you will have to paint them yourself. In this case, you can get any color. This is interesting: painting wooden windows.

Yellowed plastic is one of the reasons for painting

Advantages and disadvantages

The films produced by acrylic varnish are easy to clean; any detergents other than solvents can be used on them. Acrylic varnishes show high wear resistance; no defects form on them over time. An important plus is that this material is harmless to people. On a smooth PVC surface, one coat is enough for most paints; double coating is required only when applying compositions with a metallic effect, or in case of significant defects. This cost-effectiveness is one of the advantages of PVC painting.

Pay attention to: Painting a wooden frame

Primary requirements

The main requirement that such paint must meet is high adhesion. Unlike wood, plastic has a smooth, slippery surface and a very hard, dense structure that does not provide a high level of adhesion between materials.

Also, the coloring composition must have the following characteristics:

• water resistance;
• strength;
• resistance to mechanical stress;
• resistance to UV rays;
• color preservation throughout the entire service life;
• the absence of toxic and poisonous substances that can be released when heated;
• resistance to temperature changes;
• long service life;
• wide range of colors;
• the ability to give an object a certain texture.

The ease of application of the composition also plays an important role, since plastic windows are often painted with your own hands.

Polyurethane-acrylic paints

These dyes fully comply with all the necessary characteristics, these compositions are made on a water basis, they are often used to paint PVC, for example, plastic windows or other structures. Polyurethane-acrylic mixtures create a uniform coating that is resistant to scratches and other defects. The dye dries quickly enough on the PVC surface; if desired, you can tint the composition yourself. Thanks to these dyes, you can easily and quickly paint PVC, and it is possible to create any textured effects if you add special ingredients to the base paint.

Polyurethane-acrylic paints are made in a huge range of colors; the catalog contains more than two thousand different shades. In addition to traditional colors, manufacturers offer:

• pearlescent paints;
• with sparkles;
• metallic

Subtleties when painting surfaces

Choosing paint for PVC

It is better to paint plastic in one layer at room temperature. Pre-application of primers is not required here.

If you have the opportunity to use a spray bottle for work, this way the coating will be done better. Also, paints and varnishes can be applied using brushes or a roller.

Materials for painting take about 8-10 hours to dry, it all depends on the temperature. But, you can use painted plastic only after 3 days. If you need, the coating can be repeated, but only after the first layer has completely dried.

It is also worth paying attention to the fact that in any room there are many objects that can cause a fire or be damaged in a fire. To avoid this situation, it is better to buy fire-retardant paint for painting, the thinner of which is ordinary water.

Preparing the surface for painting

We paint PVC with our own hands

Painting a plastic profile with water-based acrylic paints has certain advantages, including:

• preparatory work is carried out quickly;
• the surface dries quickly at room temperatures;
• within 8-10 hours the finish gains strength at a temperature of only 20o;
• painting can be done either manually or with automatic sprayers;
• the paint has great decorative features (imitation wood, mother-of-pearl, metallic, etc.).

An important point before applying paint to a product is its preliminary preparation.

First of all, you must be sure that there is no dirt, silicone or polyurethane foam residues, greasy marks or other debris on the surface that will prevent strong adhesion of the plastic to the paints.

To properly prepare the surface, you can follow the following instructions:

1. using a cloth or compressed air, remove crumbs and debris from the surface of the product;
2. soak with specialized cleaning agents that are made specifically for polystyrene;
3. remove grease and other lubricant mixtures from the surface, thereby removing static tension;
4. Allow the surface 10-15 minutes for the cleaner to evaporate.

Following the advice of experts, it is better to purchase a specialized cleaner-activator for PVC, which, when applied, forms micropores on the surface that improve the adhesion of materials to each other.

Another known method for increasing adhesion is sanding the plastic and then priming it. But, this process is much more complicated and requires certain skills and experience from the master.

Related article: Which wallpaper to choose for uneven walls

Dyeing process

First of all, you need to prepare the tools and everything you need. PVC windows are painted using a regular paint brush or a construction gun. Equipment for painting PVC profiles can be purchased at a hardware store. If a gun has been selected for painting, it must be clean and dry.

Water-based paint is applied to the profile in one layer. If you want to get a metallic color, you will need two layers. When painting plastic windows, you can use different spraying technologies. Updating the appearance of plastic windows by painting gives the profile some protection and a qualitatively new look. Once window structures are painted, they are much easier to maintain.

Applying paint to the profile, painting plastic windows

The paint, profile and gun must be the same and match the work area - at least 18 ° C, relative humidity no more than 80%. The air gun must be clean and dry. Recommended application parameters: operating pressure 2–3 atm., nozzle size 1.6–2.2 mm.

Water-based paint on PVC is applied in one layer, with a wet film thickness of at least 80 microns; a smaller thickness may affect the adhesion strength to the plastic profile being painted. Painting PVC with a wet layer thickness of more than 120 microns will lead to a significant increase in drying time and may affect the decorative appearance of the coating.

Painting plastic windows in colors with a metallic effect can be done in two layers to enhance decorativeness. The first layer of metallic effect paint is applied to the plastic with a wet film thickness of 80–100 microns. After intermediate drying (10–12 hours), a second, finishing layer of colorless water-based varnish for PVC is applied with a wet film thickness of 80–100 microns.

To paint PVC windows, you can use various air spray technologies, for example: RP - “reduced pressure”, HVLP - “high volume, low pressure” or AirMix / AirCoat - “a combination of airless and air application”.

Types of profile painting

After mixing special additives and stabilizers into the PVC composition, polyvinyl chloride changes its grayish tint to snow-white. This is the base color of the plastic profile. Depending on the further technological cycle, it may remain unchanged or change completely during the production process. Today, several methods for coloring profiles are actively used:

• coextrusion method;
• spraying method;
• mass coloring.

In addition, manufacturers offer a service for applying varnish to the surface of polyvinyl chloride products. Thanks to this treatment, the profiles acquire a noble matte shade and become velvety to the touch. The varnished coating is cured at high temperatures in special ovens, so it has a sufficient margin of safety.

When purchasing any painted windows for installation on the sunny side, you need to be extremely careful. It is necessary to ensure the quality of PVC, which should withstand operation at elevated temperatures. This is due to the fact that with prolonged exposure to sunlight, frames and sashes can become deformed if the quality of the polyvinyl chloride is not high enough. In addition, in such cases it is recommended to choose lighter shades.

Methods for painting PVC products

In industry and subsequent processing of plastic profiles, the following types of coloring are used: bulk dyeing, co-extrusion (co-extrusion) painting, film lamination, spraying, varnishing. Let's look at these methods in more detail.

1. The method of imparting color to a PVC composition in bulk has already been touched upon earlier. Its essence is to add powdered dye (pigment) directly when mixing polyvinyl chloride resin with additives. There is an opinion that when dyeing plastic in bulk, only white and brown colors can be obtained, however, in the production of, for example, gutters, green, red and some other colors are successfully obtained in bulk.
2. The co-extrusion painting method involves adding an additional extruder (extruders) to the extrusion line. This additional extruder is designed to add a thin layer of well-colored polymer to the front surface of the product. This polymer can also be polyvinyl chloride or compatible polymers, such as PMMA (polymethyl methacrylate, acrylic) or ASA (acrylonitrile styrene acrylate).
3. The process of lamination with film, most often also acrylic, occurs after direct extrusion of the plastic, however, the laminator can be installed as part of the extrusion line closer to its end. Using this method, both a single-color pattern and a complex image can be applied to the product.
4. When painting by spraying, two-component colored acrylic varnishes are usually used. This method allows you to paint plastic in different solid colors.
5. Varnishing the surface allows you to obtain a pleasant matte structure of the product. First, the varnish is applied to the surface of the product, after which the surface is dried in a special oven. This method can produce a wide variety of surface colors, as well as roughness and non-standard texture.

Co-extrusion painting method

Let us dwell in more detail on this important method for polymer processing. The co-extrusion method for producing colored profiles is the most durable and one of the most cost-effective. It allows you to use a PVC composition with reduced aesthetic characteristics, secondary somewhat contaminated raw materials, etc. as the main raw material. With co-extrusion, the coloring layer will never separate from the main product, will not be washed off, etc. Also, when using the right types of plastics for the coextrusion layer, such as ASA styrene copolymer, this layer protects the material from fading and degradation from natural elements for decades.

Fig.2. Gutter painted by co-extrusion

The disadvantage of the co-extrusion coloring method is the greater complexity of the equipment used (an additional extruder is needed), the greater complexity of the extrusion tool (due to the additional flow of the polymer melt) and, as a consequence, the higher cost of the equipment. In addition, a coextrusion line is more demanding in terms of personnel and is not so easy to set up.

Aerosol paints

Acrylic spray paint for PVC is especially suitable for painting plastic products. The container protects the paint from air penetration and the formation of a film on the surface. On the labels of such paints you can find the words: “Plastic” or “Multi-Surface”.

Advantages

• high level of adhesion;
• ideal for painting small parts and hard-to-reach places;
• does not require additional tools;
• creates an even and smooth coating;
• dries quickly;
• economical to use.

Flaws

• If cleaning is not done in a timely manner, the nozzle may dry out;
• spray painting requires certain skills.

Coloring plastic at home

You can handle painting plastic materials yourself; this will greatly save your budget. Turning to professionals is very expensive. To carry out the work at home yourself, you will need to take care of your own safety by preparing protective equipment, also prepare all the necessary tools (listed above), and perform all stages of the work. They will be discussed in detail further.

Painting methods

The paint coating is available either in cans or in aerosols. Which option to choose depends on the size of the product and the experience of the person who will carry out the painting work.

Spray cans are more appropriate for a small painting object; they are not difficult to work with, but before you start, you should try it out by spraying a little paint on an unnecessary surface, this will help you understand how best to spray to get the desired result. In general, the aerosol method will give a good, even coating. This method does not allow you to mix tones, and thus it will not be possible to apply clear color boundaries.