EP2678218A1

EP2678218A1 - Method for protecting surfaces from fouling

Info

Publication number: EP2678218A1
Application number: EP12706197.6A
Authority: EP
Inventors: Serge Sirlereaux; Thierry AGARD
Original assignee: Renolit SE; Uniflockage Sas; UNIFLOCKAGE S SA
Current assignee: Renolit SE; Uniflockage Sas; UNIFLOCKAGE S SA
Priority date: 2011-02-25
Filing date: 2012-02-22
Publication date: 2014-01-01
Also published as: KR20140005173A; DE102011012517A1; US20130048211A1; WO2012113562A1; CA2827149A1; CN103402866A

Abstract

The present invention relates to a method for protecting surfaces that are normally underwater from fouling, wherein the invention provides that a deformable, self-adhesive film is flocked with fibres and applied to the surface.

Description

Method of protecting surfaces from fouling

The present invention relates to a method for the protection of normally under water, especially under seawater, surfaces from fouling.

The fouling of ship hulls and other normally submerged surfaces with stuck plant and animal organisms such as algae, shells, barnacles represents a major problem. There are already many different proposals to protect against fouling. An overview is e.g. "Antifouling Product List 2010", Growing Atlas e.V., 1st edition edition 2010.

Of particular interest are those protective measures that require no or at least little chemical agents. These include

Coatings with fibers, as described on page 31/32 of the above publication and in EP 643,657 and EP 1 964 620. The application of fibers to hulls, however, is expensive.

There is therefore a further object to provide an effective protection against fouling, which is easy and inexpensive to apply, acts for a sufficiently long time and requires as little active ingredients that reach the environment and can be harmful there.

Surprisingly, it has now been found that it is possible to solve this task with deformable, self-adhesive films with flocking.

The invention thus achieves the above objects with a method of protecting normally submerged surfaces from fouling, wherein a deformable, self-adhering film is provided, flocked and adhered to the surface. Since the film is deformable, it can also be glued accurately on curved surfaces such as ship hulls. A coating of

Interstices with adhesive and subsequent flocking on the ship's hull, as in EP 1 964 620, can be dispensed with. In contrast to EP 643 657 only one operation is necessary, in which the film is connected by means of the pressure-sensitive adhesive to the surface.

Deformable, self-adhesive films for protection against fouling are known per se. However, these are equipped according to the prior art with the smoothest possible surface in order to reduce the adhesion of fouling organisms and to ensure a low flow resistance. Suitable materials are all sufficiently abrasion-resistant, salt water-resistant and UV-stable plastics. Preferred materials for the films according to the invention are polyvinyl chloride (PVC), polyurethanes (PU), butadiene and isoprene-based polymers, polyolefins such as polyethylene (PE) and polypropylene (PP). Particularly preferred are polymers based on vinyl monomers, in particular polyvinyl chloride (PVC). Also suitable are films based on PVC and or ethylene vinyl acetate (EVA).

The film may in known manner have additives and additives which are used in the usual amounts. In the case of PVC films, plasticizers, stabilizers and, if desired, pigments and / or dyes are preferably included. For a suspension PVC

(S-PVC) are e.g. 60-70% by weight PVC; 5 - 10 wt.% EVA; 15-25% by weight polymer plasticizer, 2.0-3.0% by weight barium / zinc stabilizer; 5 - 10 wt .-% modifier and 0.5 - 1, 0 wt .-% light stabilizer typical. The amount of pigments / dyes depends on the color desired. It is possible to provide biocidal agents in the sheet material.

Deformable means in the context of the present invention that the film has an elongation at break of at least 200%. The 2% module is from 15 to 25 N / 15mm. The stretching force is in the range of 25 to 40 N / 15mm. Elongation at break, 2% modulus and yield strength are measured in accordance with DIN EN 527 3/2/200.

The production of the films according to the invention is carried out in a conventional manner, e.g. on calanders. Multilayer films, which may have two, three or more layers, are obtained by coextrusion, direct extrusion or lamination. These methods are known to the person skilled in the art.

The film is coated with a pressure-sensitive adhesive so that it can be glued directly to the surface to be protected. Suitable in principle are all adhesives that show sufficient resistance to seawater and good adhesion both with the film and with surfaces of metal, wood, paint, etc. Preference is given to using a pressure-sensitive adhesive based on acrylates. In a preferred embodiment, the pressure-sensitive adhesive becomes a biocidal

Active ingredient added, for example CU2O, an isothiazolinone and / or a pyrithione.

For flocking adhesives and fibers are used, which are suitable for prolonged contact with water. As fibers, for example, polyamide and polyester fibers are well suited. But also copper fibers, silver fibers or fibers with biocidal active ingredients in and / or on the fiber are advantageous. Fibers with biocidal active ingredient are known per se and have hitherto been used in medicine. According to the invention, fibers having a content and / or a coating with copper (I) oxide, isothiazolinones, pyrithiones and other biocidal, in particular algicidal, active compounds known per se are suitable. The incorporation of the active substance or substances in the fiber provides for an extension of the duration of action, since superficially lost by washing out lost drug from the fiber interior can diffuse. It is also possible to incorporate a first active ingredient in the fiber and another as a coating

applied. In a preferred variant, fiber blends are used to obtain a batt with both hydrophobic and hydrophilic fibers. Here, the surface tension (measured according to DIN 53364) should be> 50 dyn, preferably> 60 dyn for the hydrophilic fibers and <30 dyn, preferably <20 dyn for the hydrophobic fibers.

Typical fiber lengths are from 0.1 to 8 mm, preferably from 0.3 to 5 mm and more preferably from 0.5 to 3 mm. The fiber thickness should be in the range of 1, 5 to 100 dtex, preferably 2 to 50 dtex for polymer fibers and 5 to 100 dtex for metal fibers. Preferred diameters are from 10 to 100 .mu.m, preferably from 30 to 70 .mu.m.

The flocking takes place with fiber densities in the range of 100 to 500 fibers / mm ² , preferably from 150 to 250 fibers / mm ² .

As an adhesive for anchoring the fibers seawater resistant adhesives are selected, which are matched to the film. For PVC films, for example, plastisols, which are customary for the production of flocked T-shirts, are suitable. A typical recipe includes PVC, plasticizer, filler and

Tackifiers.

In a preferred variant, a biocide is added to the adhesive in which the fibers are anchored, e.g. Copper 1-oxide or an isothiazolinone such as 4,5-dichloro-2-N-octylisothiazolin-3-one. Also mixtures of biocides are possible.

For the production of the films used according to the invention for the protection of the deformable film is first equipped with the pressure-sensitive adhesive self-adhesive. The pressure-sensitive adhesive is / is preferably covered with a release liner, eg siliconized paper. The self-adhesive film is then coated with the adhesive to anchor the fibers and then flocked in a conventional manner. The film is then usually wound on rolls and stored. For attachment to the surface to be protected, the surface is, if necessary, cleaned to remove adhering fouling and / or dirt. The surface should be clean, free of grease and dry. The film is, optionally after cutting and / or peeling off the Releaseliner, placed on the surface and pressed.

The film is preferably glued to shock. Gaps between adjacent film webs can be easily and quickly closed by appropriately cut pieces of film. A coating with adhesive is not necessary, so that there is no danger with the adhesive to glue the fibers in the already attached flocked films. It is also possible to form one edge of the film in a narrow strip without fibers and to glue the film with an overlap. In a further variant, it is conceivable that the fibers are removed after sticking in a strip bridging the shock and the shock is covered with a strip of flocked film. The strip may have the same structure as the film or else e.g. have a higher concentration of biocide or biocide at all.

The film of the invention is particularly suitable for

Protection of seawater contacting parts such as ships, off-shore equipment, buoys, etc. It is easy to install by means of the pressure-sensitive adhesive and the deformability. Another advantage is that, if necessary, the film can be much easier separated from the surface, as about the usual

Paints. The film can be peeled off, if necessary under the action of heat.

The invention will be explained with reference to the following examples, but without being limited to the specifically described embodiments. Unless otherwise stated or necessarily different from the context, percentages are based on weight, in case of doubt on the total weight of the mixture. The invention also relates to all combinations of preferred embodiments, insofar as they are not mutually exclusive. The information "about" or "approx." in conjunction with a numerical indication, means that at least 10% higher or lower values or 5% higher or lower values and in any case 1% higher or lower values are included.

Example 1

A film was made on a calender. The film formulation comprised: 54.7 wt.% PVC with a K value of 80; 8.5% by weight of ethylene-vinyl acetate copolymer; 1.8% by weight of acrylate modifier; 21, 5 wt .-% polymer plasticizer;

2.5% by weight of stabilizer; 1.7% by weight of costabilizer; 8.5% by weight of titanium dioxide;

0.7% by weight of light stabilizer and 0.1% by weight of lubricant. This film was first coated with a pressure-sensitive adhesive based on acrylates and the pressure-sensitive adhesive was covered with a siliconized paper. Then, to anchor the fibers, a plastisol of 100 parts PVC (Solvin NA), 52 parts DIDP and 40 parts CaC0 ₃ containing 7% isocyanate-containing tackifier was applied. In the plastisol partially 20 parts of the filler CaC0 _{3 were} replaced by copper (I) oxide, mixed with about 1% of the Cu ₂ 0 amount of isothiazolinone or pyrithione. The film was flocked in a manner known per se with the fibers specified in Table 1.

Table 1

The films can be well mounted on a ship's hull.

Example 2

Sheets Nos. 1, 4, 5, 9, 10 and 11 were stuck on metal sheets and the antifouling effect was examined. The panels were attached to the circumference of rotatable discs, which were arranged in Southeast India in the sea. The discs are either rotated continuously for the examination or rotated alternately for one month and not rotated for one month. During the rotation, the speed of rotation and the circumference of the slices for the panels results in a speed of passing water of 20 knots (about 38 / hour). Once a month, the slices with the slices are taken out of the water and the surface examined for growth. A photo is taken, the number of barnacles counted and a flock of algae and other marine animals

Living organisms logged. Then the slices are placed back in the sea until the next examination. The results are also given in Table 2. Table 2

Bewuc is after

Surface fibers: 1 month 2 months 3 months 4 months 5 months 6 months

PET / PA, dynamic no algae no no no no

3.3 dtex, 1mm long alternating no no no no no no no

PA, 6.7 dtex, 1mm long little bit little bit

alternately ./. ./. with silver algae algae seaweed algae

PA, 6,7 dtex, 1mm long alternating no no no no no ./. ./.

PA, 22 dtex, 2mm long, with

little

30% Cu ₂ O and no no algae algae

seaweed

3% CuPT in the adhesive

PA, 22 dtex, 2mm long, with little

dynamic no no no no algae 30% Cu ₂ O algae

and 3% ZnPT in the adhesive

alternately no no no no no no no

PET with biocide, 4.6 dtex,

alternately no no no no no no ./. 0.5 and 1 mm long (1: 1)

In some cases (slide 4, 9 and 10) a few algae were found, in four cases (slide 9 and 10) a somewhat stronger fouling with algae.

Barnacles had never attached themselves, although on the edges of the boards which were not protected by the film according to the invention, barnacles were in each case found in a short time, usually after 3 months, but sometimes even after one month.

For the films 9 (dynamic) and 10 (alternately), the photos are shown in Figures 1 and 2.

Claims

Patent claims

1. Methods for protecting those normally submerged

Surfaces from fouling, characterized in that

a deformable, self-adhesive film is flocked with fibers and applied to the surface.

2. The method according to claim 1, characterized in that the surface is a ship's hull.

3. Method according to claim 1 or 2, characterized in that the fibers are treated with one or more biocides.

4. Method according to at least one of claims 1 to 3, thereby

characterized in that an adhesive used for flocking is equipped with one or more biocides.

5. The method according to at least one of claims 1 to 4, characterized

characterized in that a pressure-sensitive adhesive that makes the film self-adhesive is equipped with one or more biocides.

6. The method according to at least one of claims 1 to 5, characterized

characterized in that the film is equipped with one or more biocides.

7. Method according to at least one of claims 3 to 6, thereby

characterized in that the biocide is selected from copper (l) oxide,

Isothiazolinones, pyrithiones and mixtures thereof.

8. The method according to at least one of claims 1 to 7, characterized

characterized in that the fibers are polyamide fibers, polyester fibers,

Silver fibers or copper fibers or mixtures thereof can be used.

9. The method according to at least one of claims 1 to 8, characterized in that fiber mixtures are used to obtain a fiber web with both hydrophobic and hydrophilic fibers, the surface tension (measured according to DIN 53364) > 50 dyn for the hydrophilic fibers and <30 dyn for the hydrophobic fibers.

10. The method according to at least one of claims 1 to 9, characterized

characterized in that fibers with lengths of 0.1 to 8 mm, preferably from 0.3 to 5 mm and particularly preferably from 0.5 to 3 mm are selected.

1 . Method according to at least one of claims 1 to 10, characterized

characterized in that fibers with diameters of 10 to 100 μm, preferably 30 to 70 m, are selected.

12. The method according to at least one of claims 1 to 11, thereby

characterized in that the flocking takes place with fiber densities in the range of 100 to 500 fibers/mm ² .

13. The method according to at least one of claims 1 to 12, characterized

marked that the film is glued together.

14. The method according to claim 13, characterized in that in the area of the joint the fibers are removed or not applied and the joint is taped off with a strip.

15. The method according to at least one of claims 1 to 12, characterized

characterized in that the film is formed with a fiber-free edge area and is glued in an overlapping manner.