US 2352810 A
Description (OCR text may contain errors)
Patented 4, 1944 GRAININ'G INK VEHICLE I Raymond A. Swain, Bellevnc, Ky., assignor to In,
terchemical corporation of Ohio Corporation, New York, N. Y., a
[No Drawing. Application May 17, 1941, v Serial No. 393,927
3 Claims. (01. gem-'22) v This invention relatesto the art of artificial woodgraining, and it is particularly directed to new vehicles useful in the preparation of graining inks, and to graining inks containing these vehicles. a
The usual method of ternsof fine woods on either cheap wood or metal is, first, to apply a base coat, or ground coat, to the surface to be grained which hides the true appearance of the surface and provides a background color for the grain design. This is printed with the grain pattern by means of a resilient roll bearing the graining ink in the desired pattern from contact with an intaglio cylinder. After the graining ink has dried, a covering of a clear varnish or resinous composition; tinted with a transparent color if desired, is applied to protect the printed graining and to provide a finish resembling genuine wood finishes. Sometimes, when applying an artificial grain to wood, the ground coat may be omitted and the graining ink applied directly to the bare wood.
reproducing grain patn Graining inks must have certain physicalcharacteristics which distinguish them fromthe ordinary intaglio printing inks. In the case of i wood graining inks where no ground coat is employed, the ink 'must not bleed or run noticeably along the fibers and pores of the wood, and yet it is desirable that the ink be completely absorbed. by the wood and feather out slightly on coming in contact therewith in order to obtain a clear but pleasingly soft appearing grain. Where the graining ink is-applied over a ground coat, especially in coating metal, it is essential that the ink should bond wellto the ground coat, which means that the solvents in the ink should not deleteriously afl'ect the ground coat, That is, the graining ink should not cause either embossing or shelving (i. e'. separation of the various films or coats). Likewise, the ink should be capable of bonding well with the top coats of clear lacquer or resina This invention provides new'vehicles for graining inks more nearly embodying the desired physical properties enumerated above than grainm ink vehicles lmown in the prior art. Graining inks formulated with these vehicles will bond tightly to all of the usual ground'and top coatings without shelving or embossing and they may be retouched. The invention also includes the graining inks formulated with these vehicles.
' The vehicles of this invention may be broadly defined as condensation products of phthalic anhydride or acid), glycerol, benzoic acid and drying or semi-drying oil fatty acids, containing a plasticizer (and solvent if necess ry) intimately admixed therewith. The solvent or plasticizer preferably should have a fairly high boiling point in order that it may not evaporate from the graining inkbut remaininthe dried or hardened ink after it has been applied to the surface to be decorated. Generally, this requires that the plasticizer have a boiling point of at least 350 F., and where the graining ink is to be baked on the decorated surfacethe plasticizer should have an .even higher boiling point. Some of the most suitable plasticizers are the dialkyl esters of phthalic acid, and of these dimethyl phthalate is preferred. I
Since such heavy plasticizers often increase the viscosity of the graining ink or paste undesirably, it is often preferable to dilute theplasticizer with a lower, boiling solvent which will evaporate to a large extent, on application of the graining ink to decorated surfaces. Very volatile solvents are to be avoided as they will evaporate from" the ink during eizposure on the intaglio printing rolls with the result that the ink becomes nonuniform in composition. Solvents which are generally quite satisfactory are those whose boiling points are above that of water, but not greatly beyond, and it has been found that methyl ether of ethyl-. ene glycol (methyl cellosolve) is particularly suitable as a solvent. in connection with dimethyl phthalate as a plasticizer.
Although an of the commercially available drying and/or semi-drying oil fatty acids may be used in preparing these vehicles, soya bean, tung and perilla fatty acids 'give products having the desired physical properties to a greater degree than do the products of.other drying-oil acids. It is obvious, of course, that the drying oils themselves may be substituted in part for the equiva-. lent amounts of glycerin and drying oil fatty acids, and such choice is within the discretion of those skilled in the art.
The preparation of a typical graining ink vehicle according to this invention is described in the following example, in which the materials are given in parts by weight.
Example 1 Parts by weight Phthalic anhydride 351 Glycerol 236 Benzoic acid 134 soya bean fatty acids 269 Dirnethyl phthalate 606 The phthalic anhydride, glycerol, benzoic acid and soya bean fatty acids wereheated together in -described in Example 4.
2 akettleto4501'.andmaintainedatthattemperaturiefortwoandonehalfhoursinanatmosphereoi'carbondioxide. mthenddnnmbel' 'ofthemixturehaddroppedtoii cooled down and the dimethyl phthalate slowly added with constant mixing. This vehicle showed compatibility with nitrocellulose,alkydresin's,maleieg\nnsandthelike..
Generally,graininginksmadewiththisvehicle aremoresuitablei'oruseoverthebakedtyneof around coats because the dimethyl phthalate .may have a deleterious eifect on theair dried .type, due to penetration into the ground coat.
inks employing thevehicle described in Examplel are as follows, in-which the materials aresiven in parts by weight:-
Samuel-Transparent mining ink Parts by weight Blane fixe 30.00 Vehicle of Example 1 22.50 Dimethyl phthalate 7.50
The above materials were mixed and ground onarollmilltoauniformpaste. Thenanadtional 30.00 parts of the vehicle and 10.00 parts of dimethyl phthalate we're added and the mixture ground until a completely unirorm and smooth paste or obtained.
Example 3-White mining ink Parts by weight Titanium dioxide 00.10 Vehicle of Example 1 32.00 Dimethyl phth'alate .'-11.00
. The materials were ground one rollrnill until a uniform paste was obtained.
Example 4-liahouany graining ink The materials were ground together on a roll mill until the resulting paste was of uniform consistency.
Thematerialsweregroimdonarollmillas Parts by weight bladder lake 0.10 Carbon black 5.50 Bone black 8.80 .Burnt sienna 3.00 Vehicle of Example 1 54.70 Dimethyl phthalate 18.25
(Similarly, any of the standard suchasalkydandurearesinaandgmundenats containing an alkyd resin' inder are. suitable.
compositions may be applied over the ink, and the clearnitrocelluloselacquersorclear finishes made from maleic gums, urea resins and. thelike, are suitable.
It is understood that wherever phthalic ahydride is referred to in the specification and claims its obvious equivalent, phthalic acid, may
be substituted, and it is included within the m of the claims. Likewise, mixtures of fatty acids or drying and semi-drying oils may be used in place or the fatty acids derived from a single drying oil.
- -l. A graining ink having correct body for intaglio offset application, comprising coloring matter dispersed in a vehicle consisting essentially of an alkyd resin and a solvent therefor having a boiling point above that of water, and
a substantial portion thereof being a plasticiaer for the resin boiling above 350 F., whereby substantial change of ink body during application is avoided. in such quantity that correct body is attained, the resin being' a reaction product 'of phthalic anhydride and glycerol modified with .both benzoic acid, and fatty acids derived from oils selected from the group consisting of drying and semi-drying oils.
2. A mining ink having a body designed i0! intaglio oii'set application, comprising coloring matter dispersed in a vehicle consisting essentially of the reaction product of glycerol,
phthalic anhydride, benzoic acid and ma oil fatty acids, reduced to graining ink consistency with dimethyl phthalate.
3. A graining ink having a body designed for intaglio offset application, comprising coloring matterdispersed in a vehicle consisting essentially of the reaction product of approximately 24 parts by weight of glycerol, approximately 80 parts by weight of phthalic anhydride, amroximately 13 parts by weight or bennoic acid, and
Alloithese'graining'inkswiliairdry.usually ap roximately 2'! parts by weisht of soya oil fatty acids. reduced to mining ink consisten y with dimethyl phthalate. v
' nsmom) A. swam.