US1888864A - Art of printing or graining - Google Patents

Description

atented Nov. 22, 192

UNITED STATES PATENT' OFFICE;

LOGAN A. MIZENER, OF WILMETTE, ILLINOIS, ASSTGNOR 'I'O CHICAGO MILL AND LUMBER. CORPORATION, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE ART OF PRINTING OR GRAINING No Drawing. Original application filed January 26, 1931, Serial No. 511,434. Dividedand this application filed November 30, 1931. Serial No. 578,211.

This application is a divisional on an original application filed by me in the Unlted States Patent Oflice under date of January 26, 1931, Serial No. 511,434.

This invention relates to the art of printing and more particularly to the art of printing or graining certain types of wood to simulate other woods having distinctive appearing grains. A particular object of the invention is to provide a composition and process by which hard or soft, plain textured woods which are relatively inexpensive and plentiful may be printed upon, or grained so as to simulate more costly varieties of wood which are in demand because of their definite and characteristic grain. Another object of the invention is to provide a printing ink or composition for the purpose described having qualities of durability and ease of application, and which will quickly set and immediately resist smearing or rubbing off after being applied to the surface for which it is intended. A still further object of the present invention is to provide a printing compound and process 'for use in printing or marking on either a wet or' dry base which may be'wood or other materials but which has particular adaptability in printing upon a wet base. Still another object of the invention is to provide a composition for the purpose described which will be simple andinexpensive to prepare and compound, eflicient in use and which may. be prepared and used by unskilled workmen to results.

Other and further objects of the invention will be apparent from the disclosure in the following specification.

This invention has particular adaptability in the cigar box industry in which wood such as so-called Spanish cedar which has a distinctive aroma and grain has been used extensively for pacln'ng good grades of cigars and tobacco. The tobacco purchasing public has thus through aperiod of years come to the point of associating the aroma and particularly the grain of Spanish cedar with high grade tobacco. A demand has thus been created by producers of tobacco products. for wooden containers which, by their appearproduce effective,

ance, will produce the impression that high grade tobacco is packed therein.

this result has been to glue extremely thin veneer of Spanish cedar or mahogany to plain textured, inexpensive woods which are more plentiful than are Spanish cedar or mahogany at the present time. Paper has also been printed to imitate the grain of the wood and containers ofordinary plain wood have been covered therewith. v

Another suggested method has been to print or grain the surface of this less expensive plain textured wood with marks or lines so as to simulate the grain of the more desirable varieties. However, many dificulties have been encountered in printing directly on the wood itself, because heretofore it has never been deemed practicable to print on wood until after it has been dried'to about the normal moisture content of kiln dry wood. The reason for this has been that the graining compounds in use could not give satisfactory results unless the lumber or wood were dried down to a certain low point of moisture content. If the lumber had an excess of moisture the ink would run and blur and the narrow lines which are most needed absorption capacity collapse in. the drying process more than the portions of lesser absorption capacity regardless of how mechanically true and erfect the surface may have been when out rom-the wet or green logs' or fiitches. Because of this harder character after drying much wear and tear is caused to the printing machinery, especially to the impresslon means such as printing rolls or the like. In addition, it is difficult and nearly impossible to obtain a uniform application of the grainingink to dry,unfinished lumber because of the irre ularities of the surface arising during the drying; and even when the board has been surfaced there yet remains a certain amount of warp or twist, as well as considerable rigidity, in the lumber, which causes damage to the machinery involved in the printing operation. For these reasons the production of printed lumber or boards has always been a more or less slow, uncertain and cumbersome operation, and the cost has therefore been too great to warrant production on a substantial scale.

When the printing composition of the present invention is used the particular amount of moisture contained in the impression receiving base is not material even when this moisture content reaches its upper levels. This finds particular application in the case of the utilization of rotary cut lumber or socalled veneer stock due to the fact that the logs are always impregnated with considerable moisture before going to the lathe or other device on which the lumber is cut. This moisture contentmay vary considerably depending upon whether a given piece of lumber has been cut from the log near its outer surface or near the center. It'has been found that the weight of the sap wood, that is, the wood adjacent the outside of the log, with the moisture therein, is frequently 7 5% to 100% greater than the bone dry weight of this portion of the log but this percentage may decrease considerably toward the center. For example, one speciesof gum has been found to vary from 118% moisture in the sap wood to 82% moisture near the heart for a sixteen inch diameter log which has been immcrsed for several hours in a bath of hot water. The compound of the present invention finds particularly advantageous use, compared with printing compounds heretofore known, in operating on freshly cut, socalled veneer lumber having a moisture content in excess of 20%. The present invention, however, is not confined in its use to wet lumber but gives very desirable results on lumber of ordinary commercial dryness and kiln dried lumber. By the terms wet wood or wet lumber as used herein any lumber having a moisture content in excess of that present in air dry lumber is to be understood. The pres ent compound is applicable to lumber in any of its forms, although it is usually applied to thinner cut boards which may be produced either by sawing, slicing or rotary cutting.

In preparing th printing compound, it is desirable to employ a carrying vehicle such, for example. as a starchy substance which may be prepared with water to assume a thick consistency as by means of cooking.

Leeasee Corn starch is very well adapted for the purpose since it is comparatively inexpensive and easily available and is simple to prepare for the present purpose. Any other starch such as potato or tapioca flour or the like can be used.

To the desired amount of starch in an aqueous medium any desired coloring matter may be added. Aniline colors have been found Very satisfactory in this respect. being simple to handle and giving desirable results.

To this mixture of starch and coloring matter is added a quantity of glycerine and vinegar, the last mentioned ingredient being preferably cider vinegar having approximately a 4% acetic acid content. Any other suitable acetic acid containing substance may be employed for this purpose. It is of particular note in this connection that apparently the interaction between the glycerine and acetic acid is an important factor in giving to the compound its good adhering properties, particularly when applied to wet lumber, since these ingredients combine to form a water resistant compound which serves to retain the ink upon the wood fibers regardless of the moisture that may be present in the wood.

It has been found in practice, where lumber fresh from the cutter or slicer is grained, that the temperature of the lumber will govern to a great extent the desirable proportion of glycerine to acetic acid. In the usual method of preparing logs for slicing or 1:0- tary cutting, they are first subjected to the ordinary steaming process or to a water bath which is controlled to maintain a temperature ranging from in the neighborhood of 165 to about 200 F., more or less. The steaming process or water bath renders the wood soft and water-soaked to a degree varying with the texture or density of the particular variety of wood subjected to a given length of treatment. This facilitates cutting the sheets or slabs of lumber from the log or fiitch with a minimum of tearing of the fibrous structure. way still retains a temperature of about 150 F., more or'less, upon leaving the lathe or slicer, the temperature varying according to the cooling effects of the pheric' conditions.

In carrying out the process it has been found that when the temperature of the wet material operated upon is at about ordinary room temperature fairly good results can be obtained where the glycerine content of the compound is present in the proportion of about one part of glycerine to about eight parts vinegar. However, if the lumber is to be treated fairly soon after leavingthe cutter and while having a temperature considerably above ordinary room temperature, it has been discovered that more dependable results are obtained with a glycerine content of about Lumber treated in this prevailing atmos one part of glycerine to six or seven parts of vinegar; but if the conditions are such that it is desirable to grain the lumber almost immediately after leaving the cutter and before it has had time to cool and, especially during warm weather, a higher glycerine content should be used to avoid spreading or whiskeringof the grain or other design. In fact, when graining warm wood direct from the cutter, a quantity of glycerine in about the proportion of one to four parts vinegar has been found very satisfactory. It is apparent, therefore, that a glycerine content within a range of one in about four to eight parts vinegar will prove suitable under a variety of particular conditions. However, I do not wish to be limited to these exact proportions since it has been determined that the glycerine content may be somewhat varied above and below the proportions given depending upon various factors such as 'moisture and temperature. It may be noted,

however, that when the glycerine content is raised lmuch above-one part to four parts of vinegar the composition is likely to become gummy and sticky and has a tendency to smear when applied.

When the ingredient mentioned have been mixed together, it has been found desirable to cook the mass until it has reached a suitable thickness or viscosity, After the composition has cooled, preferably to about atmospheric temperature, it is ready for use.

The following examplewill illustrate a preferred form of the present embodiment of the invention:

h A graining compound or ink prepared as above described and in the proportions given has proved very elfetcive in practice and particularly' when woods of softer texture are grained, either dry or wet.

In the above example the starch may be varied between 95 and 100 parts with relation to the rest of the mixture or in certain cases other suitable fillers may replace part of the starch. .The amount of coloring mat- Jter used depends more or less upon the ininvention.

desired to be obtained. The variation of the glycerine and vinegar with relation to each other has previously been dlscusse'd in some detail. The amount of water may be varied sary, but if a vinegar having an acetic acid content of less than about 4% is used and consequently more of this ingredient is necessary, then a proportionally smaller amount of water will be needed. Atmospheric conditions also affect the amount of-water required. In any event, the amount of water should be such as to give the mass a jelly-like consistency after it has been prepared by cooking as above stated and allowed to cool.

After it has been prepared by cooking as above stated, the mixture is preferably al lowed to stand in a comparatively large vessel so that it will cool slowly. This tends to cure the mass and gives it theproper consistency for eflicient application. The preferred time for cooling has generally been found to be about 15 hours where the ink is applied by the roller type of printing mechanism.

It is apparent from the foregoing that the composition may be varied within certain limits to be effective under a varying range of conditions both of the moisture and temperature of the lumber and the general conditions and temperature of the atmosphere. The composition is one that can be readily made up without requiring a large amount of skill on the 'part of the operative.

While the composition of the above described formula gives entirely satisfactory results for moderate speeds and when the lumber is of substantially uniform and comparatively soft texture, nevertheless it has been found that where a considerable range of extreme conditions is present in the lumber or other impression receiving material the inclusion of additional ingredients, with the composition heretofore-described, insures obtaining satisfactory results under these extreme conditions. This is true where any one or more of a combination of conditions prevails, for example, where the atmosphere is warm and humid and the lumber comes to the printing mechanism at a temperature not much reduced from the temperature at which it leaves the severing mechanism, or the wood is of comparatively hard texture or the printing mechanism is running at a comparatively high speed with the wood of relatively high moisture content. To this end it has been developed that if certain albuminous substances such. for example, as blood albumin in its various forms or other proteids or .albumins are mixed with the above described product and properly controlled so as to time the setting qualities of the resulting composition at the proper point of application of the ink, it is rendered still more eflicient and certain without danger of blurring or whiskering in spite of relatively high temperatures and speeds, or moisture content of the material operated upon. Furthermore, by the addition of such albuminous substances the setting of the ink is accelerated and the color tone and durability of the finish are improved. 4

It is a well-known fact that blood albumin has the properfy of coagulating and forming a water-insoluble substance when subjected to heat. It is also a known fact that certain chemicals such as paraformaldehyde will act upon blood albumin in a cold liquid medium to cause it to congeal and set, without the application of heat, to form a fairly water-resistant compound.

While paraformaldehyde is capable of reacting with the blood albumin to cause it to coagulate and form a tough, water resistant coating, it has been found necessary to employ an alkaline substance which will retard the action of the paraformaldehyde as long as the mixture is maintained in relatively large masses and which will lose its effect upon the paraformaldehyde, either by evaporation or by combination, when the composition has been applied as a relatively thin film upon the surface being imprinted. Ammonium hydroxide has been found well suited for this purpose.

In preparing a preferred form of the albuminous addition to the composition, a desired quantity of light or dark blood albumin is soaked in a liquid medium until it can be stirred to an even consistency. Thereupon the retarding agent and coagulant are stirred into the albumin mixture. The addition of a small amount of salt is often desirable in the composition as a preservative, particularly where the climate is such that there is danger of the organic matter putrifying on account of its standing for some time prior to use. However, the salt is most beneficial when aniline colors are employed because it enhances both the brightness and setting of the colors. The use of this latter ingredient is optional, of course, and may be omitted without deleterious effects if desired.

The blood albumin portion is preferably made up of the following ingredients in about the following proportions by weight:

, P t Blood albumin (light or dark) about 3d 5 Ammonium hydroxide (Sp. G

0.90) about 1 Paraformaldehyde about 4% Water about 37 Sodium chloride about 8 As has been previously brought out, the blood albumin containing composition will, due to the coagulant, set without the application of heat; however, since the wet lumber is generally put through some sort of heated drier to expedite removal of the excess moisture, there will, as a rule, be a further setmesses ting action upon the blood albumin by reason of the heat. Heat is not, however, essential to form a satisfactory grained surface.

The blood albumin portion of the printing composition is separately prepared and then added by agitation to a batch of the color carrying compound which may be made up as previously outlined. Ihe resultant mixture takes on a jelly-like form when fully prepared and may be kept for many hours prior to use by keeping the exposed surface of the mass damp as by laying dampened cloth thereon.

After numerous experiments and tests l have concluded that the various reactions taking place in the compound as a result of adding the albumin composition may be described as follows. The two batches of ingredients, after being prepared separately,

are mixed together after the first mixture described herein has been allowed to cool and become properly "cured. The first batch retains substantially the acid characteristics imparted to it by the acetic acid and color and the albumin batch retains the alkalinity characteristic of its components On mixing the two batches together there is no doubt a reaction initiated between the acetic acid and the ammonium hydroxide but this interaction is apparently retarded to a large extent by the viscosity of the agglomerate due largely to the starch. In any event, it appears that sufficient alkalinity is retained in those parts of the mixture containing the paraformalde- I hyde so as to leave suflicient ammonium hydroxide to effectively retard or inhibit any action by the paraformaldehyde on the blood albumin for eighteen or more hours after the two batches have been mixed together. However, when the prepared ink is spread in a thin film on the impression receiving base, which is generally somewhat acid, the ammonium hydroxide is dissipated, either due to the acidity of the base or because the additional moisture with which the film comes in contact on the impression receiving surface enables a more intimate contact of this alkaline substance and the acid of the composition; or the ammonia which is volatile may be almost instantly evaporated because of the thinness of the film and the heat of the base. Nevertheless, upon application of the ink there appears to be an immediate action of the paraformaldehyde upon the blood albumin to set it and, together with the other ingredients causing the formation of a clear, permanent impression of the desired design.

A graining composition produced in accordance with thepresent disclosure lends itself admirably to rapid quantity production of artificially grained lumber to simulate Spanish cedar, mahogany or the like. This composition may also be used to reproduce advertising designs or wording upon wooden panels used for various purposes such as shiploo . ping cases or boxes and the like in a similar manner to that described for the graining operation. The desired design, whether a grain, advertising matter or other markings, may be printed or impressed upon the receiving surface by means of impression mechanism of any suitable character and having suitable impression means such as the recessed cylindrical printing roll or other more or less conventional means. In operation this impression applying mechanism may be operated as close to the point at which the lumber is cut from the log as is practical; and the graining may be carried on as rapidly as it is physically possible to handle the output. The ink sets so rapidly after application that there is no staining of the superimposed unprinted surface of the lumber as it is stacked in coming 05 the press prior to removal to the rier.

It has been found in practice that the use of lumber having a considerable moisture content when applying thegraining composition of the present inventlonha's many advantages. Outstanding among these advantages is the fact that the surface presented to the printing rolls or other impression means is as true and smooth as when the material leaves the cutting mechanism because the plane of the surface has not been varied by reason of collapsing of the less dense portions of the wood which ordinarily occurs as a result of-drying, as has been heretofore explained. Furthermore, since the wood fibers are more resilient and pliable due to their water-soaked condition, the wet lumber will cause a minimum of wear and tear to the printing rolls or machinery. Another great advantage of this process lies in the fact that one drying operation sufiices both for drying out the veneer as well as for completing the drying and setting of the graining ink.

Excellent results have been obtained by using such plain woods as red gum, tupelo, cottonwood, magnolia, black gum, poplar, basswood and lynn for the base upon which to apply the graining effect. However, there are other woods which may be used with equally favorable results.

While the invention is particularly applicable to printing on wood it is not to be considered as entirely limited thereto as it can be applied to advantage for printing on other substances, especially when they have a moisture content substantially above normal.

While the present description, sets forth apreferred embodiment of the invention, numerous changes may be made in the process and compound without departing from the spirit of the inventiom'and it is, therefore, desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

I claim: I 1. The method of graining which consists in printing directly upon the surface of wet wood with a water-resistant compound comprising a starch, coloring matter, glycerine and acetic acid, in which said last mentioned ingredients are present in the proportions of at least three times as much glycerine. as acetic acid.

'2. The process of graining wet lumber comprising cutting slabs from moisture laden logs or fiitches and before removal-of the moisture content therefrom applying a graining compound formed of suitable quantities of color carried in a vehicle of starch, vinegar and glycerine.

3. The process of imprinting markings upon wet lumber which comprises cutting sheets or slabs from green or water-soaked logs or flitches and before removal of the moisture content therefrom applying a graining compound which will not spread or smear on a wet surface and which comprises color carried in a vehicle of starch, vinegar and glycerine, said last mentioned ingredients being present in the proportion of about 4: to 8 parts vinegar to one part glycerine.

4. The method of graining wood which comprises severing a layer of wood of the desired thickness from a flitch having a moisture content of 20% or more and mechanically applying to said wood layer a .graining compound comprising starch, coloring matter, glycerine and vinegar in which the glycerine and vinegar are present in amounts of about 4: to 8 parts of vinegar to each one part of glycerine.

5. The method of imprinting which comprises preparing a water-resistant compound or ink including starch, coloring matter, vinegar and glycerine, in which the two last mention-ed ingredients are present in the proportion of 4 to 8 parts vinegar to each one part glycerine, and thereafter applying said compound to a wet base by means of printing, mechanism.

6. The method of graining which consists in printing directly upon the surface of wet lumber with a water-resistent compound comprising starch, glycerine, acetic acid, blood and paraforglycerine, blood albumin, ammonium hydroxide and paraformaldehyde.

8. The method of graining lumber directly 53 messes as it comes from the severing mechanism and in which the graining compound comprises starch, coloring matter, glycerine, vinegar, blood albumin, and coagulating means for the blood albumin.

9. The method of printing on wet wood which comprises introducing into the log or flitch an excess of moisture over normal moisture content, cutting a slab of wood from m said log or flitch and before removing suflicient moisture from said slab to cause collapsing of any of the surface of the wood, whereby it will lack uniformity of caliper, printing thereon with a compound unaffected by the m moisture and in which glycerine and acetic acid are combined to form the water-resistant element,

10. The method of printing on wet wood which comprises cutting the wood into slabs my while the wood has a moisture content above 20% of its bone-dry weightand printing thereon with suitable pigments carried in an agglomerate base of cooked starch or the like to which suitable water-resistant means has been added to prevent spreading of the ink when it is applied to the wet surface.

11. The method of printing on wet wood which comprises cutting the wood into slabs while the wood has a moisture content about 30 20% of its bone-dry weight and before removing sufficient moisture to cause collapsing of the surface of the lumber, whereby it will lack uniformity of caliper, printing markings thereon with an ink comprising suitable 35 pigments intermixed with an agglomerate, viscous base and blood albumin in which the blood albumin is set by a congealing agent whose action prior to the application of the ink to the wood is inhibited by a retarding w agent,

Signed at Chicago, Illinois, this 24th day of November, 1931.

LOGAN A. MIZENER.