JPS5936787A - Polyethylene material for coating - Google Patents

Abstract

Coating, esp. by printing with a powder or paste, is carried out with polyethylene powder (I) having a different polymer (II) adhering to the surface of the particles. Pref. (I) is LDPE powder. (II) is a polyamide, polyurethane, polyester, polyacrylate, polyvinyl halide, polyvinyl acetate, polyether and/or polyalcohol. A plasticiser (bisphenol A) may be added. The amt. of (II) is 0.5-25 (1-10) wt.% w.r.t. (I). (II) is applied as a soln. or dispersion and dried. A double dot coating may be used, the coated (I) providing a barrier layer preventing the top layer flowing into the interfacing. This barrier layer consists of (I) contg. 0.5-10% (II), whilst the top coat consists of a hot melt adhesive powder of copolyamide (m.pt. 80-130 deg.C) or copolyester (m.pt. 115-140 deg.C). (I) has a particle size distribution of 0-200 (9-80) microns. The breaking load of the (II)-coated (I) at room temp. is (min. 25, pref. min. 50%) lower than that of uncoated (I). The technique is esp. useful for coating woven, knitted and nonwoven textile, real and artificial leather and foams. The surface properties of (II)-coated (I) are about the same as those of (II) powder, allowing (I) to be applied in the same way as other more costly hot melt adhesive powders, e.g. (co)polyamides and (co)polyesters.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the use of polyethylene powder as a coating (applied by powder printing or paste printing) for lining flat products, in particular upper fabrics. , concerns a polyethylene powder having a small and at least partially heterogeneous polymer layer. As a flat product, on woven fabric,
Among others, polyethylene has been used as a material for forming coatings of powdered hot-melt adhesives. This is because they are inexpensive and have the necessary strength when washed or cleaned. Polyethylene was previously used for powder coating of washer lining materials. For this purpose, the application of polyethylene powder to the lining phase has usually been carried out using the powder spot method. In this method, finely powdered polyethylene (prepared by grinding bulk particles obtained from low-pressure polymerization of ethylene) is pressed into the recesses of an engraved roller, and then the fabric strip is formed.
Moved to second place. In addition to this application method, a paste coating method using premixed pasty low-pressure polyethylene powder can be used. However, in coating lining materials for outerwear, polyethylene is used, since extremely strict conditions are required when ironing the outerwear (otherwise it will damage the upper fabric). Hardly used. Polyethylene is currently used for outerwear applications as a base layer in two-layer screen-type coatings with two laminated layers (onto which is placed a copolyamide, polyester, etc. that readily adheres to the upper fabric). It just has the potential to be used. Such a method itself is described as the Powder Spot Duo method in German Patent No. 2,536,911.

Due to the low primary cost of low-pressure polyethylene powder, the overall cost of the coating is cut by approximately an order of magnitude without having to use harsh conditions during ironing. Additionally, other advantages of duocoating are expected since commercially available low pressure polyethylene powders meet the desirable ranges of conventional duonealing for both melt viscosity and melting point. But West Germany! If polyethylene were to be used in the method according to Patent No. 2,536,911, the coating would be disturbed at the operating temperature, making it impossible to transfer spots cleanly. It is clear that commercially available copolyamide powders and low pressure polyethylene have very different tendencies to cake (set). So far, it has not been possible in practice to perform satisfactory powder spot duo coatings using low pressure polyethylene as a base layer.

The object of the present invention was to find a solution which, when using polyethylene, makes it possible to coat flat products without exhibiting uneven behavior in the engraved recesses.

This objective is achieved by the use of polyethylene in the manner described above. In this case, the polyethylene powder particles used include
It is characterized by having a part made of a foreign polymer attached to its surface.

That is, the particles are characterized in that their surfaces are partially or completely covered with a heterogeneous layer containing a polymer.

According to the invention, among the polyethylenes, preferably powders from low-pressure polyethylene synthesis are used. Within the spirit of the invention, preferred low pressure polyethylenes include 19
Melt index (DIN 53735) at 0°C and 21.6 N (load) 2 to 35F/”
It has S. The melting point of polyethylene such as is 122℃
The temperature is between 0.95 and 137℃, the density is between 0.95 and 137℃, and the density is between 0.95 and 137℃.
It is 6s9/i.

The foreign polymer deposited on the exterior surface of the polyethylene can be either natural or synthetic. The heterogeneous polymer-containing layer may be made of only a heterogeneous polymer, or may be made of a mixture of this polymer and a softener.

The polymer and/or softener preferably has an acid amide group, a urethane group, a carbonate group, a carbonate ester group, an ether group,
Contains polar groups such as nitrile groups, rogen groups, sulfone groups, amide groups, etc. Examples of polymers having such polar groups include natural or synthetic acid amide resins, polyurethane', natural or synthetic polyalcohols, polyacrylic acid, polyvinyl acetate, polyethers, polyacrylonitrile, Polyvinyl chloride can be used. Although it is described as a "polymer"2 here, it may also be a copolymer with another polymer. Any mixtures of the above polymers can be used depending on the purpose, and these mixtures also function to modify the surface of the polyethylene powder particles. Examples of softeners having polar groups include cyclohexyl phthalate, doluol, sulfonic acid amide, bisphenol A, and the like.

The proportion of foreign polymers can vary within a wide range, and generally the proportion of foreign polymers ranges from 0.5 to 2 by weight of the polyethylene.
It is 5chi. However, in many embodiments of the invention, especially when the percentage of foreign polymer is between about 1 and 10% by weight (
It has been proven that satisfactory results can be obtained.

This foreign polymer is attached to the surface of the polyethylene powder particles by various methods. For example, within the spirit of the invention, the foreign polymer can be applied as a solution or dispersion onto the polyethylene powder 1-1 and then dried. Also, a relatively simple method is mixing, and in this case, care must be taken to ensure sufficient and homogeneous mixing.

For mixing, a high-speed rotating duff mixer, for example, is suitable. To check the homogeneity of the mixing process, it is sufficient to add a small amount of pigment that is dispersed in water. If the mixture no longer shows pigment bleed, it is sufficiently homogeneous. As a general rule, the polyethylene particles are first placed in a mixing vessel, the previously mixed ingredients are added thereto, and mixing is carried out. The drying process is carried out at, for example, 100°C until water no longer evaporates.
Let's do it. For example, on a conventional tray, drying can be accomplished in about 1 to 2 hours. Mixing time with a high speed Da7 mixer is approximately 5 to 10 minutes.

Polyethylene powder particles partially or completely coated with a foreign polymer are applied in a variety of ways as coatings for flat articles, particularly upper textile linings. Although powder printing is the preferred application method,
Preference is given to using the paste printing method. The modified polyethylene powder modified according to the invention by adhering to its surface a foreign polymer can be used as such or in combination with other polymers in the so-called double spot coating method. In the latter method, the polyethylene can, on the contrary, partially or completely form a layer with a foreign resin.

When the modified polyethylene powder particles according to the invention are applied in double spot coatings, they constitute a blocking layer and/or a lower layer of the double spot coating and prevent the upper layer from flowing into the lining.

In this case, the lower layer which is placed directly on the lining "2" contains modified polyethylene powder particles with 0.5 to 25% of heteropolymerization (A"S1 content, based on the weight of the polyethylene) or The weight-modified polyethylene powder particles can also be placed directly on a lower screen placed on the surface of the polarized IL coating or lining, and a second layer of other polymers can be placed on this lower screen. However, within the spirit of the invention it is possible for the lower layer of the double coating to contain modified polyethylene powder particles according to the invention only in part. For this purpose, the modified polyethylene powder particles can be admixed with conventional polymers.

If, according to the invention, modified polyethylene powder particles are used as the lower layer of the double coating, special advantages are obtained with Mikichi using copolyamides or copolyesters as the upper layer. Among the commercially available copolyamides, melting points range from 8° to 130°C, 160°C, 21°C,
．． Melt index (DI) at 6 N (load)
N 53735 ) 5 to 757710 minutes are preferred. When a copolyester is used instead of a polyamide or a copolyamide, the melting point range is 5 to 140°C, 160°C, 2
Melt index (DIN) at 1.6N (load)
53735) with 10 to 25 g/10 min are particularly advantageous.

A particularly preferred use according to the invention is a copolyamide meltable adhesive bed or melting point in which the lower layer consists of modified polyethylene powder particles with a heteropolymer proportion of 0.5 to 10% by weight and the upper layer has a melting point range of 80 to 130°C. This is the case for a double coating consisting of a copolyester meltable adhesive bed with a temperature in the range 115 to 140°C. However, the modified polyethylene powder particles can also be used with a screen-type single coating (no second screen layer laminated) and is still within the spirit of the invention.

The exact selection of polymers or their combination with softeners is determined through coating tests.

This test is also possible in a manner known per se by a skilled person, in addition to determining measured data on the caking behavior of the powder to be treated. In order to quantitatively determine the caking behavior, the height is 5ctn and the base area is 10cr! A measuring means can be used consisting of two semi-cylindrical cups (for example made of iron) forming a hollow cylinder with . For accurate measurements, the powder is loosely filled into this hollow cylinder, then stirred with a needle and loaded IF with a metal ring weighing o, sK (its base area is 10i).

Then, a further load is applied (4.5 Kz). The load is applied for 5 minutes at the respective selected temperature (powder and device are layered already at this temperature).

After removing all loads, open the semi-cylindrical cup. The formed compressed cylindrical fracture was detected in a storage container (weight 14 g, base area 10 crt!) superimposed on it for gradual loading. Using commercially available copolyamide powders with particle sizes 0 to 200 microns and 0 to 80 microns, the measurement data shown in the table below were obtained at 25°C and 50°C, when measured under the above conditions. 50℃ (this temperature is room temperature, l
: In the measurement data shown for 25℃ higher)
1. It must be taken into consideration that the destroyer is also affected by temperature data during heating. In order to be able to detect this influence, two measurement data have been cited in each table below. High measurement data fa) is heating time 2 minutes, compression time 5
The low measurement data (bl is the preheating time at 50°C; 3 hours, and the compression time is 5 minutes).

Corresponding to the data in the table, the fracture factor is such that at 25° C. it is the value of the copolyamide (copolyester value) and increases sharply with increasing temperature like the copolyamide (copolyester). The alteration of the particle surface of low pressure polyethylene due to the heterogeneous adhesion layer is clearly important.

Some examples are given below, which describe some of the low pressure polyethylenes treated according to the present invention. Note that the measurement data shown in each example was obtained using samples that were heat-dried so that the water content became zero.

Example 1 10% polyamide aqueous sol 150 parts (i parts) The above components were thoroughly mixed and heated at 100° on a tray.
Dry at C.

Destroyer 25°C132p 50°C1101) Example 2 Abifor 1300/6
1000 parts by weight water
60 parts by weight of the above ingredients were thoroughly mixed and dried on a tray at 100'C.

Destroyer 25°C2451) 50'. 13゜、゛Example; 3 Bisphenol A 2.5
heavy division water
Thoroughly mix 25 parts by weight of the above ingredients and place on a tray at 1'0.
Dry at 0'C.

Destroyer 25℃ 113p 50℃ 184 \Example 4 Abifor 1300 / 6 (θ ~ 80 min) 1oo
1 part of the above ingredients were thoroughly mixed and heated on a tray at 10o'C.

Destroyer 25℃ 243p 50℃135p Implementation ν115 (BASF) 60
Part by weight water
60 parts by weight The above ingredients were thoroughly mixed, and 100 parts by weight was placed on a tray.
'C.

Destroyer 25°C 384p 50°C 453p Example 6 Lutofan 300 D
40 parts by weight Lateco D
10 @Habu water
30 parts by weight of the above ingredients were thoroughly mixed and dried on a tray at 100'.

Destroyer 25°C 270p 50°C 265p Example 7 (R'6hm Gmb 11 companies)
60 parts by weight water
20 parts by weight dicyclohexyl phthalate
10 parts by weight] The components listed above were thoroughly mixed and dried on a tray at 100°C.

Breaker 25°C 274p 50°C 165p Example 8 8 bifor 1300/6 (0-80 microns) 100 parts by weight 5 Chigelatin aqueous solution 8Q heavy weight The above components were thoroughly mixed and dried on a tray at too much °C.

Destroyer 25 't: 2 184 p50℃
124p Example 9 10% polyamide aqueous sol 1
50 parts by weight Bisphenol A
5' parts The above ingredients were thoroughly mixed and dried on a tray at 1.00'C.

Destroyer 25°C 170p 50°C 750p Example 10 Latecol D
25 heavy tail and suphenol A
3 parts), ] parts] lyolsulfonic acid amide 2 parts by weight water
The above ingredients were thoroughly mixed using a 25M meter, and dried on a tray at 100'G.

Fracture strain 25°G 250 p50°C750
p Only in the case of Examples 9 and 1o (containing bisphenol A as softener) the failure strain of the copolyamide was approached. In any of the other examples, the fracture strain was 25°C.
However, the strong increase in fracture strain when the temperature was raised disappeared. Many of the above examples showed a reduction in fracture strain. Despite this decline, these fruits //1'! The powder according to the invention in example i is suitable for producing good powder spot duo coatings. However, in practice, as in Examples 9 and 10, it is preferable to treat the powder with bisphenol A as a softening agent. In tests, such mixtures were particularly amenable to high speed coating.

For example, the modified low pressure polyethylene powder according to Example 10 has a particle size of 0 according to Powder Spora i Duo loss.
to 80 microns, melting point +10 to 120°C1 and 160°C and 21. ．． Melt index (DIN 53735) at 6 N (load) 1.4
Commercially available copolyamides with q/10 min
, engraving roller temperature 45°C, hot roller temperature 250°C
.

When used in coating operations at screen placement densities of 11 to 23 mm/in and total coating weight of two layers of polyamide and polyethylene of 10 to 20 F/m2, it can be coated without any disturbance at high coating speeds. coated. Coating speed is largely controlled by the dimensions of the hot roller and engraved roller and the type of equipment used.

Due to the adhesion of a heterogeneous layer containing polymers, the surface properties of low-pressure polyethylene powders are similar to those of copolyamides, especially if the former contains certain softeners, such as bisphenols. .

It becomes something. Therefore, both single and duo coatings can utilize the same engraving and hot roller temperatures as traditional polyamide coatings as well as polyester coatings. In this way, it can be added to other ordinary hot melt adhesive powders.
(Low L1:) to take advantage of the cost advantages of polyethylene.

Since polyester powder is almost the same as polyamide powder, it can be said that the price comparison is the same as above.

Based on the above tests and examples, according to the invention it is preferred to deposit a layer of a heterogeneous polymer on the surface of the polyethylene particles, so that the compacted cylinders of this polyethylene powder are ruptured at room temperature. It is clear that the strain is lower than the initial value without the inclusion of foreign polymeric additives. A particularly favorable result is that the strain to failure of the compacted cylinder of polyethylene powder (measured, for example, by the method described above) is 25%, preferably at least 50%, above the initial value at room temperature in the absence of foreign polymeric additives. % is obtained. According to the invention, the fracture strain (measured at room temperature) of polyethylene powder is adjusted to 0. Advantageous values are achieved when the values are approximately within the range of those of the copolyamide or copolyester powders used for conventional two-inning double spot coatings. Such copolyamide hot melt adhesive powder has a melting point of 80
Preferably, the copolyester hot melt powder has a melting point of 115 to 140°C.
Preferably. According to the present invention, it is possible to control the fracture strain of polyethylene powder coated with a heterogeneous resin, which is not necessarily theoretically elucidated, but despite current knowledge. Optimally, it should approximately correspond to the value of the copolyamide or polyester and should rise as strongly with increasing temperature as in the case of the copolyamide or copolyester powder described above. it is obvious.

Claims (1)

[Claims] 1. A material for coating applied to a flat product by a powder printing method or a paste printing method, wherein the coating material is made of polyethylene powder, and the surface of the polyethylene powder is It is characterized by having a layer of a different polymer adhered to at least a portion thereof. Polyethylene material for coating. 2. The polyethylene material for coating according to claim 1, wherein the polyethylene is low-pressure polyethylene. 3. The foreign polymer is polyamide, polyurethane,
Claim 1 which is polyvinyl acetate, polyester, polyacrylic ester, polyvinyl logenide, polyether, polyalcohol or a mixture thereof.
Polyethylene material for coating as described in Section. 4. The polyethylene material for coating according to claim 1, wherein the layer of different polymer also contains a softening agent. 5. The softening agent is bisphenol A. The polyethylene material for coating according to claim 4. 6. The amount of the foreign polymer is 0.0% by weight of the polyethylene.
The polyethylene material for coating according to claim 1, wherein the polyethylene material is from 5 to 25 inches. 7. The polyethylene coating material according to claim 6, wherein the amount of the foreign polymer is 1 to 10% by weight of the polyethylene. °8. 2. The polyethylene material for coating according to claim 1, wherein the layer of the different polymer is formed by applying the different polymer as a solution or dispersion to polyethylene powder (1-1) and drying. 9. The polyethylene powder has a particle size distribution of 0 to 2.
Polyethylene material for coating according to claim 1, having a diameter of 0.00 microns, preferably from 0 to 80 microns.