US1990474A - Oil acid varnish and product coated therewith - Google Patents

Description

Patented Feb.

This invention on. new vaamsn AND momma coa'rnn 'rnsaswrrn Alfonso M. Alvarado, Wilmington, Del, assignor I. du Pont de Nemours & Company, Wilmington, DeL, a corporation of Delaware No Drawing. Application March 7, 1931, Serial No. 520,998

11 Claims. relates to the production of coating compositions and products coated therewith, and more pa rticularly it relates to artificial leather finished with an improved top coat. Still more specifically positions suitable the invention relates to comfor finishing rubber coated fabrics such as are used for automobile tops,

rubber upholstery, etc., products resulting from and to the improved finishing. such fabrics with the coating compositions described herein.

This invention has as of coating compositions finishes or top coats for ture of artificial leather.

an object the production particularly suitable as fabrics in the manufac- A further object is the production of fabrics, particularly rubber coated fabrics, provided with a gloss, a deep black color,

excellent durabilit top coat having a high freedom from blueness, y, and

even after prolonged exposure to the Weather.

These objects, in their broader aspects, are accomplished by the manufacture of varnishes from asphalt and fatty acids and application of these varnishes, with subsequent baking or dry-- ing,to the article to be varnishes, which for the finishing of rubber finished. These asphaltic are particularly advantageous coated fabrics in the manufacture of automobile top material and artificial leather in general, are conveniently made by blending a solution of asphalt with a free fatty acid derived from drying, semi-drying, or non-drying oils, with or without the addition of the usual varnish driers. however, to add organic compounds of metals,

which compounds also as blending agents between It is preferable,

function not only as driers but the oil acids and the asphalt. Organic compounds of iron are particularly valuable as blending agents. If desired,

the oil acids may be heat-treated or blown (either in the presence or absence of organic salts of metals) prior to blending with the asphalt. In general, I prefer to heat-treat in the presence of an organic'salt organic compound V ing free fatty acids and asphalt, and the method of a metal, especially an iron Suitable varnishes comprisfor their preparation, are indicated in the following fourteen examples:

Petroleum residue Solvent naphtha Turpentine subshliiiIIIIIIIIIIIIIIII China wood oil acids Total The asphalt is cool to 425 R, an

Example I Parts by weight asphalt 100.00

heated to 500 F., allowed to equal weight of solvent naphtha is added; and the mixture is stirred until the asphalt is complet ely dissolved. To this solution good retention of gloss is added 80 parts by weight of a 50% or China wood oil acids in turpentine substitute.

Example 11 Parts by weight Petroleum residue asphalt 100.00 Solvent naphtha ..1 100.48 China wood oil acids 20.00 Turpentine 20,00 Cobalt linoleate (containing 5.80% Co.) 0.17

Total 240.65

The asphalt is heated to 500 F., allowed to cool to 425 F., an equal weight of solvent naphtha is added, and the mixture is stirred until the asphalt is completely dissolved. To this solution is added 40 parts by weight of a 50% solution of China wood oil acids in turpentine and 0.65 parts by weight of a cobalt linoleate solution in solvent naphtha, said solution containing 1.45% cobalt.

Example III Parts by weight Petroleum residue asphalt 100.00 Solvent naphtha 110.80 Linseed oil acids 160.00 Turpentine 160.00 Lead resinate (10% Pb.) 2.40 Manganese resinate (6.63% Mn.) 1.20

Tot l "534.40 The :phalt is heated to 500 F., allowed to cool to 425 R, an equal weight of solvent naphtha is added, and the mixture is stirred until the asphalt is completely dissolved. To this solution is added 320 parts by weight of a 50% solution of linseed oil acids in turpentine, 9.6 parts by weight of a lead resinate drier solution, and 4.8 parts by weight of a manganese resinate drier solution, said solutions containing 2.50%

.lead and 1.66% manganese, respectively.

The gilsonite is heated to 500 F., allowed to cool to 425 R; an equal weight of solvent naphtha is added, and the mixture is stirred until the asphalt is completely dissolved. To this solution is added 80 parts by weight of a 50% solution of castor oil acids in turpentine, 2.4 parts by weight of a lead resinate solution in solvent naphtha, and. 1.2 parts by weight of a manganese resinate drier solution in solventnaphtha, said solutions containing 2.50% lead and 1.66% manganese, respectively.

Example V Parts by weight Petroleum residue asphalt 100.00 Solvent naphtha 153. 63 Oleic a 200.00 Turpentine 200.00 Iron resina 1 23.35

Total 681.98

The asphalt is heated to 500 F., allowed to cool to 425 F., an equal weight of solvent naphtha is added, and the mixture is stirred until the asphalt is completely dissolved. To this solution is added 400 parts by weight .of a 50% solution of oleic acid in turpentine and 82 parts by weight of a solution of iron resinate in solvent naphtha, said solution containing 2.44% iron.

Example VI Parts by weight Petroleum residue asphalt 100.00 Solvent naphtha 130.00 China wood oil acids 240. 00 Turpentine- 240. 00 Iron oleate- 30.00

TotaL 740.00

The asphalt is heated to 500 F., allowed to cool to 425 F., an equal weight of solvent naphtha is added, and the mixture is stirred until the asphalt is completely dissolved. To this solution is added 480 parts by weight of a 50% solution of China wood oil acids in turpentine and parts by weight of a solution of iron oleate in solvent naphtha, said solution containing 4% iron.

Example VII Parts by weight Petroleum residue asphalt"; 100. 00 Solvent naphtha"; 110.93 Soya'bean oil acids 40.00 Turpentine 40.00 Iron resina 5.47

Tota 296.40

by weight Petroleum residue asphalt 100. 00 Solvent naphtha 129.40 Cottonseed oil acids 160.00 Turpentine 160. 00 Iron linoleate 29. 40

Total 578.

The asphalt is heated to 500 F., allowed to cool to 425 F., an equal weight of solvent naphtha is added, and the mixture is stirred until the asphalt is completely dissolved. To this solution is added 320 parts by weight of a 50% solution of cottonseed oil acids in turpentine and 58.8

parts by weight of a solution of iron linoleate in isolvent naphtha, said solution containing 2.73% iron.

Example IX Parts by weight Gilsonite c 100.00 Solvent naphtha 102. 50 Coconut oil acids 20.00 Turpentine 20.00 Iron oleate 2.50

Total 245.00

The gilsonite is heated to 500 F., allowed to cool to 425 F., an equal weight of solvent naphtha is added, and the mixture is stirred until the gilsonite is completely dissolved. To this solution is added 40 parts by weight of a 50% solution of coconut oil acids in turpentine and 5 parts by weight of a solution of iron oleate in solvent naphtha, said solution containing 4% iron.

Example X Parts by weight Petroleum residue asphalt 100. 00 Solvent naphtha 100. 00 Bodied China wood oil acids 55. 1'7 Turpentine 60. 00 Iron laurate 4. 83

Total 320.00

The asphalt is heated to 500 F., allowed to cool to 425 F., an equal weight of solvent naphtha is added, and the mixture is stirred-until the asphalt is completely dissolved. To this solution is added parts by weight of a 50% turpentine solution of China wood oil acids bodied with iron laurate. (By iron laurate is meant the reaction product of iron salts with coconut oil acids). The mixture of China wood oil acids with iron laurate is prepared from the following ingredients as indicated below:

Parts by weight China wood oil acids 91.95 Iron laurate (containing 11.43% iron) 8. 05

Total--. 100.00

The China wood oil acids are heated to 385 F. and the iron laurate is added slowly and with constant stirring. The mixture is then heated to 425 F. in the course of one hour and kept at this temperature for two hours.

Example XI t Parts by weight Petroleum residue asphalt 100.00 Solvent naphtha 100.00 Turpentine 160.00 1 Bodied linseed oil acids 140.72 Iron resinate 19.28

Total 520.00

The asphalt is heated to 500 F., allowed to cool to 425 F., an equal weight oi. solvent naphtha is Parts by weight Linseed oil acids 87.95 Iron resinate (containing 7.3% iron) 12.05

Total 100.00

The linseed oil acids are mean to 450 F. and the iron resinate isadded slowly and with constant stirring. 4 The oil acids are then heated to 525 F. in the course of one hour and kept at this temperature for two hours.

Example XII Parts by weight Petroleum residue asphalt 100.00 Solvent naphtha 121.90 China wood oil acids 40.00 Linseed oil acids 40.00 Iron resinate 10.90

Total 312.80

The following are examples of formulae con taining pigments. The ingredients are compounded in accordance with the method set forth in the previous examples.

Example XIII Parts i by weight Petroleum residue asphalt 100.00 China woodoil acids 160.00 Carbon black 26.00 Solvent naphtha.. 364.00 Iron resinate 21.84 Total- ;-:1571.34.

Example XIV Parts by weight Petroleum residue asphalt 100.00 China wood oil acids 320.00 Carbon black 69.32 Solvent naphtha -L 537.23 Iron resinate 43.67

Total 1070.22

Certain oil acids, such as China wood oil acids, are remarkable in their compatibility characteristics with asphaltic materials, especially with petroleum residue asphalts. which are generally which are satisfactorily compatible.

In spite of this exceptional compatibility, I usually do not prefer to use asphalt varnishes above 20 gallons in oil acid length when no pigments are used. When pigments are used, however, forty gallon varnishes can be employed with excellent results. To a certain extent, of course, the preferred gallon lengths depend upon the kind of oil acids used Thus, castor oil acid varnishes of longer gallon length than5 gallons cannot be satisfactorily prepared, whereas with China wood oil acids gallon varnishes can be prepared A gallon oil length, as used inthe varnish trade, designates a gallon of oil per 100 pounds of gum. By weight, this is generally about 8 pounds of oil to 100 pounds of gum. The terms gallon or gallon length or gallon oil acid length, as used herein, designates 8 pounds of oil acids per 100 pounds of 'asphalt or mixture of asphalt with resin, such as ester gum, limed rosin,

glycerol-phthalate resin containingrosin in com-- bined form, and oil soluble phenol-formaldehyde resin. For example, a 5 gallon asphalt-oil acid varnish contains approximately 40 pounds of oil acids to 100 pounds of asphalt.

Instead of blending solutions of asphalt and free fatty acids, as in the examples, the asphalts may be blended with the oil acids at elevated temperatures, the blend diluted with the required amount of solvent, and the drier or iron organic compound added to the mixture. 7

It is desirable, in some instances, to use combinations of asphalts with mixtures of oil acids. When mixtures of oil acids are used, it is sometimes desirable to heat-treat or toblow one of the oil acids or the mixture of oil acids prior to blending with the asphalts. Substantial improvements may sometimes be obtained by using mixture of oils with oil acids in the preparation of these varnishes. In order to increase the durability and to improve the drying qualities of these varnishes, pigments maybe incorporated therewith. When pigments are used, however, it is preferred to use pigments which will not react with the oil acids. In varnishes designed for use under severe conditions of weathering, I prefer to use a steam refined asphalt in preferonce to asphalts refined by other methods, such as by blowing with air. The term steam refined petroleum residue asphalt varnish, as used herein, is intended to designate coating compositions in which the principal film-forming constituents are steam refined petroleum residue asphalts and drying oil acids. However, in some cases it is advantageous to use air blown asphalts,

gilsom'te, or other bitumens in place of steam refined petroleum residue asphalts. When other asphalts or bitumens are used; however, a lower order of durability is generally obtained than when steam refined petroleum residue asphalts are used. Whereas I have mentioned ordinary varnish driers and iron organic compounds as desirable ingredients of these varnishes, it will be apparent that inorganic salts of cobalt, lead, manganese, iron, or other metals, not ordinarily used as varnish driers, may be added and caused to react with the oil acid components of the varnish, thus forming compounds efiective as driers or blending agents.

The process of the present invention finds wide application in the manufacture of rubber coated fabric for automobile top material. In the. onecoat system, which is the simplest form of my invention, the coat of asphalt-oil acid varnishjected to heating at'a suitable temperature and for a suflicient time to vulcanize the rubber and to thoroughly fuse the varnish film. By this of cure depend on the rubber compound, and' especially on the kind and quantity of vulcaniz-' ing agent used. As a rule, the temperature will lie between 240 F. and 275 F., and the time of cure'will be from 30 minutes to 3 hours.

When using my two-coatsystem, I first apply to the uncured rubber an intermediate coat. of varnish which is preferably more flexible than the asphalt-oil acid varnish used as the final coat. Excellent results are obtained, however, through application of two coats of the asphaltoil acid varnish. The intermediate coat may be air-dried, if desired, that is, dried at room temperature, but it is more advantageous from the cost standpoint to use a force-dry, that is, dry at an elevated temperature but below the vulcanizing temperature of the rubber. Thus, I usually dry the first coat varnish by heating it up to 250 F. to 270 F. in one hour, after which I apply the final varnish coat and finish by baking at a temperature of about 240 F. to 275 F. for such time as is required to complete the vulcanization of the rubber.

The following is an example of a suitable un dercoat varnish for the above varnishes:

Example XV Parts by v weight Carbon black 2.5 Bodied China wood oil and drier 20.0

Bodied linseed oil and drier 20.0

In some cases it is advantageous, after applying the intermediate varnish coat, to bake at the vulcanizing temperature for a portion of the vulcanizing period and to complete the vulcanization of the rubber by baking at the same'tempcrature after the final coat of varnish has been applied. This procedure somewhat shortens the total time required to. complete the process, but it is important that care should be taken on the one hand to avoid overvulcanization of the rubber, and on the other hand that the final coat should receive not less than about one hours treatment at the full vulcanizing'temperature in order to produce the best results and to properly condition the varnish film. However, I do not wish to limit my invention to a process which involves-baking the final coat of a two-coat system, since the final coat of varnish may be airdried or dried at only slightly elevated temperatures. This method is not, however, so desirable because the luster retention of the finish is somewhat reduced when the air-dry procedure is followed.

The two-coat system is preferred to the onecoat system, especially over a rubber coated fabric, because it has greater flexibility and retains its gloss for a longer time. Without limiting myself thereto, I believe this is due to the elastic coat of intermediate varnish acting as a buffer or bridge between the extremely elastic rubber compound and the comparatively inelastic top coat of varnish.

The varnishes herein disclosed, whether airdried or baked, are useful for finishing fabrics in the production of artificial leather generally and are especially valuable for finishing-rubber coated fabricssuch as are used on automobile tops, rubber upholstery, etc. These asphalt-oil acid varnishes are superior in compatibility and durability to other varnishes used for this purpose with which I amfamiliar. In addition to being more compatible, these varnishes do not wrinkle when baked over rubber coated fabrics even when comparatively large amounts of raw China wood oil acids are used. The excellent compatibility of these varnishes makes for good initial luster, freedom from grit, and absence of blue valleys or haze. An outstanding advantage of these varnishes over, those heretofore used is their exceptional long retention of luster on outdoor exposure.

With respect to the application of my improved varnishes to fabrics for the production of products having the characteristics of artificial leather, my process has-been described in connection with rubber coated fabrics, since these represent the preferred embodiments of the invention, but it is apparent that the finishes disclosed herein may be applied as top coats to flexible sheet material in general, such as cloth and paper fabrics or leather. My improved coating compositionsmay also be used for the production of artificial leather by finishing coated materials other than rubber coated materials such as nitrocellulose coated and linseed oil coated fabrics. The terms fiexible fabric sheeting and fabric sheet material, as used herein refer, therefore, to fabrics such as cloth or paper which may be coated with a layer of material such as rubber or pyroxylin; by spraying, spreading, calendering, or by other known methods of application.

-As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that I do not limit myself to the specific embodiments thereof except as defined in the following claims: r

I claim:

1. A coating composition comprising a mixture of free fatty oil acid and asphalt in the proportion-of from 20 to 320 parts by weight of the free fatty oil acid to parts by weightof asphalt.

3. The coating composition set forth in claim 1 in which the free fatty oil acid is drying oil acid. 4. The coating composition set forth in claim 1 in which the free fatty oil acid is linseed oil acid.

5. The coating composition set forth in claim 1 in which the free fatty oil acid is China wood oil fatty acid.

6. The coating composition set forth in claim 1 in which the free fatty oil acid is oleic acid.

7. -A process for making artificial leather which comprises applying to fabric sheet material a final coating of a varnish comprising asphalt and freefatty oil acid, and drying said coating, said varnish containing from 20 to 320 pounds by weight of the free fatty oil acid to 100 pounds by weight of asphalt.

8. A process for making artificial leather which comprises applyinz to rubber sheet material a final coating of a varnish comprising asphalt and free fatty oil acid, and drying said coating, said varnish containing from 20 to 320 pounds by weight of the free fatty oil acid to 100 pounds by Weight of asphalt.

9. A process for making artificial leather which comprises applying to fabric sheet material a final coating of a varnish comprising asphalt, drier, and free fatty oil acid, and baking the resulting product, said varnish containing from 20 to 320 pounds by weight of the free fatty oil acid to 100 pounds by weight of asphalt.

10. As an article of manufacture, a flexible fabric sheeting having a final coat of dried varnish comprising asphalt and free fatty oil acid, the free fatty oil acid and asphalt being present in said varnish in the pounds by weight of the free' fatty oil acid to 100 pounds by weight of asphalt.

11. As an article of manufacture, a rubber coated flexible fabric sheeting having a final coat of dried varnish comprising asphalt and free fatty oil acid, the free fatty oil acid and asphalt being present in said varnish in the proportion of 20 to 320 pounds by weight of the free fatty oil acid to 100 pounds by weight of asphalt.

ALFONSO M. ALVARADO.

proportion of 20 to 320-