JP2003513794A - Method for producing adhesive-coated foil-like support material - Google Patents

Abstract

(57) Abstract: A method is disclosed for coating a support material with a coating substance on a conventional coating apparatus using a so-called rotating doctor process. The method is such that the coating parameters of the coating apparatus and the composition of the coating substance are selected to match the surface properties, so that layers with randomly distributed drops of various sizes are formed on the support material. It is characterized by doing.

Description

Detailed Description of the Invention

The present invention attaches an adhesive substance to a separation foil or a separation support in a separable manner, and
The field of adhesive foils is such that pressure is applied to transfer its adhesive substance to a substrate. The invention thus relates to a method for producing a road-like carrier material with an adhesive coating on one side, as well as a coating substance in the form of an intermediate product for application to the carrier material. The support material can be, for example, paper, plastic foil, or metal foil, and can be further coated with silicone.

It is known that common support materials can be provided on one side with an adhesive substance, such that the adhesive substance is coated on the entire surface. Similar types of coated foils have been utilized in coating rolls such as those described in EP 0267396. In this case, first
The track carrier material is coated on one side over the entire surface and then cut into thin strips and wound into spools. This spool is then incorporated into the coating roll as a supply spool. The adhesive coating can then be applied or applied using a roll to a smooth substrate, such as paper. At the same time, the adhesive coating is removed from the support material by a pulling action and applied or applied to the substrate with the adhesive substance with a coating roll,
Transferred to the substrate. The used support strip is independently wound on a coating roll.

When the adhesive coating is transferred to the substrate by the coating roll,
It has been found that the adhesive substance coating cannot be smoothly peeled from the support material because the adhesive substance sticks so that the adhesive substance becomes fibrous at the location where it is peeled off.

In order to prevent this detrimental effect, a support material has been devised which, instead of using adhesive substances on all surfaces, is provided with a coating of individual points, according to West German Utility Model DE 9407704U. It is known. The advantage of similar point-shaped coatings is that when the adhesive coating is applied or applied to a substrate, there is no "fibrous detachment" in the areas not coated with the adhesive substance that are located between the points of the adhesive substance. In addition, it is possible to obtain a smooth peeling line.

The point-shaped coating of the support material is usually carried out by a printing process, for example the so-called “hot melt”, especially flexographic printing process (utilization of printing block rolls). This process is very complicated and expensive.

The object of the present invention is therefore to provide a rapid coating method which makes it possible to coat a support material in spots with an adhesive substance, at the same time being cheap and easy to carry out. Another object of the invention is to provide an adhesive material that can be used to implement the method according to the invention.

According to the invention, a dot-shaped coating is applied to the support material using known coating equipment. By using a homogeneous coating over the surface area, the coating equipment is applied to the coating in the conventional manner of use. Unexpectedly, it has been found that the same coating device can also be used to apply a dot-shaped coating to a support material. However, in contrast to the conventional type of use of coating equipment for homogeneous coatings, the properties of the adhesive material are such that instead of a homogeneous layer, a coating containing a substantially irregular dot pattern is obtained. And in combination with the properties of the support material and, where applicable, certain process parameters.

In order to obtain a dot-shaped coating pattern, the optional operating parameters of the coating device are simultaneously adjusted to the materials used as adhesive substance and carrier material.

In general, it can be said that full surface adhesion provides the highest adhesion. The foil-like support material can be coated with the adhesive provided by the method of the invention, and according to the method of the invention, intaglio printing (printing with a plate with deep edges) or flexographic printing. Adhesive materials with high point densities close to 100% to ideal full surface coatings can be obtained in a simpler way than with conventional mechanical printing methods. Nevertheless, the above-mentioned detrimental behavior of the whole surface coating such as "fibrous detachment" was not observed.

The following is a detailed description of embodiments of the invention with reference to the accompanying drawings. As can be seen from FIG. 1, the coating device comprises a tank 1 in which a liquid coating substance 2 is arranged. A cylindrical application roll 3 is placed in the coating substance 2. At this time, the axis of the coating roll is arranged slightly above the surface of the coating substance 2 and extends perpendicularly to the paper surface of FIG. The coating roll 3 is driven by a motor to rotate about an axis. As shown in FIG. 1, this rotational movement takes place in the counterclockwise direction.

The coating apparatus further includes two idle rolls 4 and 5 and a feed roll 6. The axes of the idle rolls 4 and 5 and the feed roll 6 extend parallel to the axis of the coating roll 3. Both the idle roll 5 and the feed roll 6 are movable in the vertical direction perpendicular to the axis thereof.

The track-shaped carrier material 7 used for the coating is guided by both idle rolls 4, 5. The carrier material 7 is thus at its end a supply spool (not shown in FIG. 1) located in front of the first idle roll 4.
Is rolled out from. After passing through the second idle roll 5, the carrier material 7 at the other end is wound by a winding device into a cylindrical cartridge (FIG.
(Not shown). Winding up of the coating is done by a rotatable chill roll with extensive pulling means and drive. Thus, the drive moves the chill roll into a rotational movement about its axis, which unwinds the carrier material 7 from the supply spool, which is guided by the idle rolls 4 and 5 and wound onto the take-up spool.

A rotating doctor blade 8 is provided between the feed roller 6 and the second idle roll 5.
Is attached. The rotating doctor blade 8 comprises a thin rod with a particular type of external thread. The axis of the bar extends parallel to the axis of the coating roll 3. Alternatively, the rotating doctor blade can be formed from a thin rod with a thin wire wrapped around it. In addition to the rotating doctor blade method,
It is also possible to employ a comma-shaped doctor blade as shown in FIG. 2 and blades of other configurations as shown in FIGS. 3 to 5. The rotating doctor blade 8 is arranged such that its vertical position lies approximately on an imaginary connecting line connecting between the bottom ends of both idle rolls 4 and 5. The feed roll 6 is vertically movable so as to press the support material 7, the upper side of the doctor blade 8 and the upper side of the coating roll 3 in the lower position.

The coating substance 2 is applied to the support material 7 as follows. During the rotational movement of the coating roll 3, a part of the coating substance 2 remains attached to the outer peripheral surface of the coating roll 3. When the support material 7 is pressed against the application roll 3 by the feed roll 6, the coating substance 2 adhering to the outer peripheral surface of the application roll 3 can be applied to the entire bottom surface of the support material 7. In this way, a flat coating of the carrier material 7 is obtained, the carrier material 7 being pulled in the winding direction and over the idle rollers 4, 5. Between the coating roll 3 and the rotating doctor blade 8 a more or less homogeneous layer of coating substance is formed on the bottom side of the carrier material 7. In this position, the thickness of this homogeneous layer largely depends on the properties of the coating substance and of the surface of the support material.

Furthermore, the bottom side of the carrier material 7 is pulled along the top of the rotating doctor blade 8. The rotating doctor blade 8 is moved in the direction of rotational movement about the axis by a motor. Alternatively, the rotating doctor blade 8 can also remain stationary.

The rotating doctor blade 8 contacts a part of the entire surface layer of the carrier material 7 and strips it off. The stripped coating material 2 then flows back into the tank 1. The residual coating material remaining on the support material 7 usually forms a homogeneous layer on this support material.

Surprisingly, as will be explained in more detail below, by appropriately adjusting the composition of the coating substance 2 to the surface properties of the support material 7, the support material 7
It was found that droplets were formed on the surface of the. At this time, the size of the drops formed on the bottom side of the support material 7 and the distance between them depend on the characteristics of the doctor blade 8, in particular the depth of the thread or the thickness of the wire wound on the doctor blade 8. Roughly depends on.

A drying stage is arranged between the idle roll 5 and the winding device.
After the support material has been pulled past the idle roll 5, it passes through this retractable drying stage.

As mentioned above, whether the homogeneous layer is formed on the support material 7 or the irregularly arranged individual drops are formed after coating is dependent on the properties of the coating substance 2 and the support. It substantially depends on the surface properties of the material 7. If drops form,
The size of the drops and the distance between the drops depends in particular on the surface properties of the coating substance 2 and the support material 7.

The formation of drops of the coating substance 2 on the support material 7 is generally the result of a proper selection of the properties of the coating substance 2 and the surface properties of the support material 7. In this case, the surface stress of the coating material 2 and the surface stress of the support material are mutually related so that drops are formed on the support material 7 with the coating material 2 being at least below a predetermined surface density. It is important to be adjusted to.

The coating material 2 according to the invention comprises the following components: a) water plus the following components: 2% to 12% polyacrylic acid butyl ester, 1% to 5% acrylonitrile. Copolymer of acrylic acid alkyl ester, acrylic ester containing 40% to 95% of carboxyl groups,
0% to 50% polyvinyl acetate, 0% to 2% defoamer, 0% to 5% pH
An adhesive mixture consisting of a value adjusting means, and b) 20 to 50% by weight of water added to the mixture consisting of a) and b),
It is an adhesive dispersion containing. In particular, the adhesive dispersion according to the invention contains 4 to 10% by weight of polyacrylic acid butyl ester, 2 to 4% by weight of acrylonitrile and acrylic acid alkyl ester copolymer, 50 to 90% by weight of carboxyl groups. Includes an acrylic ester copolymer. The antifoaming agent is 0 to 2% by weight, particularly 0.5 to 1.
It may be contained in an amount of 8% by weight. The pH value adjusting means is usually required in an amount of 0 to 5%. As the defoaming agent, a polyether derivative of fatty acid can be used. pH
A so-called "dispersion" is used as the value adjusting means. These dispersions are usually treated with a nitrogen-containing compound characterized by an alkaline reaction, such as an aminoalcohol, especially 2-amino-2-methylpropanol (+ 10% water), or an organic amine, such as an alkylamine or ammonia solution. is there.

Conventional additives such as colorants, oxidation stabilizers, binders, fillers (fillers) and the like can be added to the adhesive mixture. The water content of the coating substance 2, ie the adhesive substance dispersion, is in the range of 20 to 50% by weight, preferably 25 to 50%.
It is 45% by weight, particularly 30 to 43% by weight, but 35 to 40% is preferable.
Therefore, the corresponding content of solids is 50-80%, preferably 55-75%.
, In particular 57 to 70%, but preferably 60 to 65%, which in each case applies to the total adhesive dispersion.

Examples of the support material 7 include polyethylene terephthalate, polybutylene terephthalate, triacetate, polyamide, polyimide, polycarbonate, PV.
A plastic foil formed of C (polyvinyl chloride), polypropylene, polyethylene, cellulose acetate, polyacrylate can be used, but it is also possible to use a metal formed of, for example, aluminum or copper, and this metal can be used. Is
If necessary, silicon treatment can be performed. The support material 7 has proven to be advantageous on both sides siliconized coated paper. Thus, siliconized paper is preferred because siliconized paper is widely used for general purposes. Although support materials of any strength can be used, it is preferred to utilize stable support materials having a weight per unit surface area of 10 g / m ² or greater. An important property of the support material is that it is essentially water repellent and the cohesive force in the applied adhesive substance dispersion is greater than the adhesive force between the applied liquid adhesive substance and the support material. It has become. This is presumed to distribute the adhesive substance dispersion in the form of drops on the foil.

The following composition of coating material 2 listed in Examples 1 to 5 below was applied to this coating material 2 in order to produce a spot coating created in drop form after being coated on a support material. It is suitable. Several embodiments are described below. Percentage and ratio data are based on weight unless otherwise stated.

The raw products or extracts used in the following examples have different properties and thus different effects. Differences in product properties may be due to the manufacturer's specifications, especially solids content, viscosity, velocity gradient, pH value, thickness, median particle size, minimum film formation temperature, dispersion type, plasticizer content. Amount, tolerance to other ingredients and dispersions, surface area properties, mechanical properties such as mechanical resistance, tear resistance and elongation at tear, and
Depends on glass transition temperature, stability to light, optical effects.

Example 1 The following ingredients were used as a mixture as listed below: a) Polyether derivative of fatty acid (foaming inhibitor) in 20 ml of water of 0.06 part b) Dispersion of 0.05 part (pH (hydrogen ion index) = 8 to 9.5) c) 0.35 part Polyacrylic acid butyl ester aqueous dispersion of d) 0.22 parts of acrylonitrile and acrylic acid ester copolymer aqueous dispersion e) 3.00 parts of an acrylic acid ester copolymer containing a carboxyl group Dispersion f) 2.70 parts of an aqueous dispersion of an acrylic acid ester copolymer containing a carboxyl group g) 0.06 parts of light blue Lanco-Beit (produced by Langer & Co.) where components e) and f). The difference between and is that the constituent e) has a higher solids content,
That is, it has a solid content of 69%, and a pH (hydrogen ion index) value and viscosity different from those of the constituent component f).

Component a) is placed in a reaction vessel and component b) is added at room temperature with gentle stirring. Further stirring is carried out in order to prevent even slight foaming during the sequential addition of the raw products c) to g). After the addition is complete, about 5 minutes, about 5
The mixture is stirred at 0 revolutions / minute. Agitation can be extended up to 30 minutes. This creates an aqueous and viscous dispersion that is less viscous. The mixture thus produced can be treated after 1-2 hours. The mixture can be left aged for 10 to 20 hours. The coating of non-viscous preparations produces irregularly arranged asymmetric sticky points by means of a rotating doctor blade device or a comma-shaped doctor blade.

The improvement of the tackiness of the coating material as explained above increases the amount of components a) and f) and adjusts the foam suppressor (component a) and the pH value correspondingly. Can be achieved by The viscosity of the above composition is
Co. Of the B8-efflux viscometer according to DIN 53211. A median outflow time of 4.1 seconds ± 0.3 seconds was achieved.

Example 2 a) 0.1 parts of a polyether derivative of a fatty acid in 100 ml of water (foaming inhibitor) b) 0.15 parts of dispersion (pH (hydrogen ion index) adjustment) c) 3.00 parts Polyacrylic acid butyl ester aqueous dispersion of d) 1.00 parts of acrylonitrile and acrylic acid ester copolymer aqueous dispersion e) 8.00 parts of acrylic acid ester copolymer aqueous solution containing a carboxyl group Dispersion f) 16.0 parts of an aqueous dispersion of an acrylic acid ester copolymer containing a carboxyl group g) 10.00 parts of an aqueous dispersion of a polyvinyl acetate copolymer h) 0.08 parts of light blue Lanco -Beit (manufactured by Langer & Co.) where the difference between components e) and f) is that the component e) has a higher solids content,
That is, it has a solids content of 69%, a pH value different from that of constituent f) and a higher viscosity than constituent f). This mixture results in increased stickiness.

Component a) is placed in a reaction vessel and component b) is added at room temperature with gentle stirring. Further stirring is applied in order to prevent even slight foaming during the sequential addition of the starting products c) to h). After the addition is complete, the mixture is stirred for a further 10 minutes at about 50 revolutions / minute. Agitation can be extended up to 30 minutes. This creates an aqueous and viscous dispersion that is less viscous. The mixture thus produced can be treated after 1-2 hours. Mixture 10-20
You can leave it lying for hours. In this case, too, the coating of the non-viscous preparation produces irregularly arranged asymmetric sticky points by means of a rotating doctor blade device or a comma-shaped doctor blade.

Example 3 a) 0.15 parts of a polyether derivative of a fatty acid in 250 ml of water (foaming inhibitor) b) 0.2 parts of dispersion (pH adjustment) c) 8.00 parts of polybutyl acrylate Aqueous Dispersion of Ester d) 1.60 Parts Aqueous Dispersion of Acrylonitrile and Acrylic Ester Copolymer e) 10.00 parts Acrylic Ester Copolymer Aqueous Dispersion Containing Carboxyl Group f) 22 0.0 parts of an aqueous dispersion of an acrylic acid ester copolymer containing a carboxyl group g) 22.00 parts of an aqueous dispersion of a polyvinyl acetate copolymer h) 3.0 parts of a polyvinyl acetate copolymer Aqueous dispersion i) 0.08 parts of light blue Lanco-Beit (produced by Langer & Co.) where the difference between constituents e) and f) is that the constituent e) has a higher solids content,
That is, it has a solids content of 69%, a pH value different from that of constituent f) and a higher viscosity than constituent f). This mixture results in increased stickiness.

Component a) is placed in a reaction vessel and component b) is added at room temperature with gentle stirring. Further stirring is applied in order to prevent even slight foaming during the sequential addition of the starting products c) to i). After the addition is complete, the mixture is stirred for a further 10 minutes at about 50 revolutions / minute. Agitation can be extended up to 30 minutes. This creates an aqueous and viscous dispersion that is less viscous. The mixture thus produced can be treated after 1-2 hours. Mixture 10-20
You can leave it lying for hours. In this case, too, the coating of the non-viscous preparation produces irregularly arranged asymmetric sticky points by means of a rotating doctor blade device or a comma-shaped doctor blade.

The difference between g) and h) is that h) has a higher solids content, showing different pH values and higher viscosities.

The double-sided silicon coated paper had a surface weight per unit surface area equivalent to approximately ^{40~42g / m 2 (1.8g / m} 2) had a particular advantage as the support material for all the cases described above It is known to be a material. Furthermore, it is possible to obtain the same good results using a transparent polyester foil having a thickness of 23 μm and a silicon coating on each side corresponding to 1.3 g / m ² on the front and back sides. It was

In order to obtain a relatively regular point pattern of the tacky coating material 2 on the support material 7, the average speed of the support material is 5 to 15 m / min. Has been found to be preferable when doing. Temperatures of 80-110 EC (conductivity) in a drying stage of length 8 m are suitable for drying the droplets on the support material.

The rotating doctor blade 8 is provided with corresponding properties in order to obtain a coating of support material with the required surface thickness. The surface density of the coating substance 2 on the carrier material 7 is predetermined by choosing a doctor blade 8 with a specific type of surface, i.e. a doctor blade 8 with a particular depth of thread. . In this case, when coating the support material 7 with one of the reference substances, 5-25 g / m ² (doctor blade: 5-2
It has been found that a rotating doctor blade 8 which forms a homogeneous coating over the entire surface by wet application (application in the wet state) in the range of 5Φ) is advantageous.

Example 4 a) Polyether derivative of a fatty acid (foaming inhibitor) in 0.15 parts water 150 ml b) 0.2 parts dispersion (pH control) or AMP c) 4 parts polybutyl acrylate Aqueous Dispersion of Ester d) 0.8 Aqueous Dispersion of Acrylonitrile and Acrylic Ester Copolymer e) 4.00 parts Aqueous Dispersion of Acrylic Ester Copolymer Containing Carboxyl Groups f) 15 0.0 parts of an aqueous dispersion of an acrylic acid ester copolymer containing a carboxyl group g) 6.00 parts of an aqueous dispersion of a polyvinyl acetate copolymer h) of 8.00 parts of a polyvinyl acetate copolymer Aqueous dispersion i) 0.08 parts of light blue Lanco-Beit (produced by Langer & Co.) Here, component a) is placed in a reaction vessel and component b) is added at room temperature with gentle stirring. It is. Further stirring is applied in order to prevent even slight foaming during the sequential addition of the starting products c) to g). 1 more after the addition is complete
The mixture is stirred for 0 minutes at about 50 revolutions / minute. The mixture thus created can then be treated immediately or after 1 hour.

Example 5 a) Polyether derivative of a fatty acid (foam suppressor) in 250 ml 0.25 parts water b) 0.25 parts dispersion (pH adjusted) or AMP c) 6.00 parts polyacryl Aqueous Dispersion of Acid Butyl Ester d) 1.0 Part Aqueous Dispersion of Copolymer of Acrylonitrile and Acrylate E) e) Aqueous Dispersion of Acrylate Ester Copolymer Containing 5.00 Parts of Carboxyl Group f ) 15.0 parts of an aqueous dispersion of an acrylic acid ester copolymer containing a carboxyl group g) 8.00 parts of an aqueous dispersion of a polyvinyl acetate copolymer h) 5.00 parts of a polyvinyl acetate copolymer Combined aqueous dispersion i) 12 parts of an aqueous dispersion of polyacrylic acid butyl ester h) 0.1 part of light blue Lanco-Beit (produced by Langer & Co.) where component a) is Placed in the container, while applying mild agitation, component b) is added at room temperature. Further stirring is applied in order to prevent even slight foaming during the sequential addition of the starting products c) to g). 1 more after the addition is complete
The mixture is stirred for 0 minutes at about 50 revolutions / minute. The mixture thus created can then be treated immediately or after 1 hour.

[Brief description of drawings]

[Figure 1]   Figure 3 provides an illustration of the function of a coating device according to the method of the present invention.

FIG. 2 shows a schematic diagram illustrating the configuration of another rotating doctor blade coating apparatus.

[Figure 3]   Figure 9 shows various arrangements of rotating doctor blades in the coating process.

[Figure 4]   Figure 9 shows various arrangements of rotating doctor blades in the coating process.

[Figure 5]   Figure 9 shows various arrangements of rotating doctor blades in the coating process.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09J 133/20 C09J 133/20 (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE, TR), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, G M, KE, LS, MW, MZ, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ) , MD, RU, TJ, TM), AE, AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, BZ, CA, CH, CN, CR, U, CZ, DE, DK, DM, DZ, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR , KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZW F terms (reference) 4D075 AC23 AC53 AC72 AC80 BB24Z CA36 DA04 DB01 DB18 DB31 DB54 DC40 EA06 EA35 EB19 EB22 EB56 EC11 EC35 4J004 AA02 AA09 AA10 BA02 CA03 CA04 CA06 CA08 CB02 CE03 DA04 EA01 GA01 4J040 DE021 DF041 DF061 DF071 GA19 HC01 JA03 JA09 KA38 PB01

Claims (6)

[Claims] 1. A method for coating a support material with a coating substance in a known coating device by means of a so-called rotary doctor blade process, the coating device containing a coating substance (2). (1), a coating roll (3) for coating the support material (7) with the coating material (2), a rotary doctor blade (8) for removing excess coating material (2), and the coating roll ( 3) and a feed roll (6) that presses the support material (7) against the doctor blade (8) for the coating device to apply a homogeneous layer of the coating substance to the support material. Used as usual, the coating parameters of the coating equipment and the coating properties of the coating material composition The support material is characterized in that the coating parameters are chosen such that a coating of irregularly distributed drops is formed on the support material and is adjusted to the surface properties of the support material. A method for coating the with a coating substance. 2. The coating material comprises: a) excluding water, 2 to 12% polyacrylic acid butyl ester, 1 to 5% copolymer of acrylonitrile and acrylic acid alkyl ester, and 40 to 97%. Acrylic ester containing carboxyl group, 0 to 50% polyvinyl acetate, 0 to 2% antifoaming agent, 0 to 5% pH value adjusting means, and if necessary, for coloring An adhesive mixture formed substantially of the required coloring material, and b) 20-50% by weight of water applied to the mixture comprising a) and b). Method. 3. The antifoaming agent is a polyether derivative of a fatty acid.
The method described in. 4. The method according to claim 2, wherein the means for adjusting the pH value is an organic amine, an alkanolamine, or an ammonia rubber. 5. The method according to claim 1, wherein the support material is a silicon-coated paper, or a plastic or metal foil that can be coated with silicon if desired. The method according to paragraph 1. 6. The support material (7), after being coated with the coating material, passes through a drying stage in which the droplets are dried on the support material, whereby A method according to any one of the preceding claims, wherein the method comprises firmly adhering to the support material (7).