US1946363A - Typewriter ribbon and the line - Google Patents

Description

1934. H. L. SHALLCROSS TYPEWRITER RIBBON AND THE LIKE Filed Aug. 26, 1951 j .5. An emphasized were can be typed.

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meme Feb. 6, 1934 senses This invention to typewriter end the like zibbons, more nurtieulerly to ribbons having pluiel longitudinal ships 0:. difierent inking thereon.

Present de-y printing ribbons for typewriters and. like machines usually become tmsemriceoble by perforation of the tape or by the drying or printing'typs end have s, ribbon holding device for maintaining the upper edge of the ribbon below the types". line when the mec'nine is at rest, and for rais ng the ribbon prior to the impact of type. The machines normally have s ribbon shift which the ribbon holding device to be fitted slightly at type impact, whereby to present it portion oi the ribbon adjacent upper edge, or for raising theribbon holder to a greater extent so that typing occurs near the lower edge oi the ribbon. These are respectively known es the block position of the color shift key and the red position thereof, es in the first corresponding position of the shiit key the upper or black nortion e two-color ribbon is e ployed, while in the red position of color shift key the lower or red portion oi the ribbon is employed. Since the ribbon holder must move upwardly for e greater distence when the color shift key is in the red position, the time required for this movement and the return therefrom is greater, and more energy is needed then in the block position. Hence, in employing a. singly colored ribbon in such a typewriter, the work is normally less speedy when the color shift key is in the red position than when it is in the block position. Therefore, it is advantageous to reverse the normal single-color ribbon after substantial exhaustion of its upper portion by removing it from the ribbon holder and rotating its plane through 180. Such a. procedure, however, means a curling of the ribbon between the ribbon holder and the ribbon spools by a. half turn at each side of the ribbon holder. As the ribbon is fed from a spool, by traction from the other spool, ultimately a pull is exerted by reason of the operation of the ribbon iced ieversing dewoes of the typewriter so that the formerly driven spool is disconnected, end its supply of ribbon is now drawn back through the m'bbon holder by positive rotation of the spool which has just been emptied of ribbon. The trections or pulls on the ribbon often lead to the dragging oi the curl forward onto the spool or through the ribbon holder so that in efiect the ribbon is creased and no longer is it feel in the desired manner, since the H edges have again been reversed into the former 69 position and now the exhausted edge is again presented for the type impact.

In my co-pending application, Serial No. 383; 883, filed August 14, 1929, I have set forth a. ribbon inking machine by which e predetermined 7Q layer of ink material is prepared on a. roller and then delivered to the tape. No squeezing is em-= ployed to wipe off any excess deposit from the tape, and hence the fibers oi the tops are not crushed and yet a. predetermined deposit of great uniformity is attained. It is now pronosed to em= ploy a, machine oi this type tor depositing two lengthwise strips of materiel upon 9, tone, one of these strips providing a. light ink deposit for the upper edge of the ribbon in its normal employment, while the other deposit is heavier and preferably includes on oil retaining substance such as carbon black for propelling e, thick costing upon the lower portion of the ribbon. These coatings may be of any desired relative quantity. it is preferred, however, to lie-ye ing below the saturation point oi the tops, while the lower inking is normally this saturation In employing the ribbon, the normal typing on the lightly inked strip causes a tentative exhaustion of this portion of the ribbon, and this exheustion causes a. capillary delivery of liquid from the more heavily coated lower edge of the ribbon. it will be understood that e. normally light inking is such as to substantially fill the pores of the tape, and thus prevent the capillary travel oi the ink material from the lower portion.

Owing to this constant replacement of the ink material, the upper portion of the ribbon may be employed for much longer periods of time than with the standard singly inked ribbon. Fur thermore, when the lower edge is coated with e colored material or ink, the typist may lay em= phasis on certain words or letters by operating the color shift key so that such letters are written by type impact against the more heavily inked or lower portion of the ribbon. In such a case, the two strips are inked with pigments of the some color, but with difierent quantities of ink,

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and preferably with the employment of an oil retaining pigment such as carbon black for the heavier deposit.

As a modification, it is also possible to include in the ink material for the lower strip a moisture absorbent material such as glycerine for absorbing moisture from the air to maintain the softness of the lower coating, and hence, by capillary transfer, the upper strip coating as needed.

An illustrative form of the ribbon is set forth in the accompanying drawing, in which:

Figure 1 shows a spool having a portion of ribbon extending therefrom.

Figure 2 shows on a larger scale a fragment of the ribbon.

Figure 3 is a specimen of the typewriting, showing the emphasis imparted by moving the color shift key, when the ribbon has two strips of colored ink material.

In the drawing the spool 10 may be of any type normal for the machine upon which it is to be employed. The ribbon comprises the usual tape having a lightly inked upper portion 11 and a more heavily inked lower portion 12 providing adjacent lengthwise strips on the tape.

During the course of employment of the ribbon, as the more lightly inked portion 11 delivers its ink to the paper, this tentative exhaustion is made good by the upward capillary travel of ink material from the lower more heavily inked portion 12, as represented by the arrows in Figure 2.

In Figure 3, the upper two lines illustrate the work done by typing with impact against the ink strip 11, while the lower line illustrates the effect by shifting for type impact against the lower portion 12 of the ribbon.

The two strips are of the same color, so that the upward capillary travel of material from the strip 12 into the strip 11 does not change the character of the work done by the machine, and hence the ribbon may be employed for a much longer period while delivering a standard shade of typewriting work.

In an illustrative example of the coatings employed for the adjacent parallel strips, the composition of coloring for the upper or normal typing strip or side of the ribbon may comprise a mixture of one-half base color or aniline dye, as for example, material commercially known as Nigrosine Base, and one-half carbon black. The coloring material for the heavy or lower side of the ribbon may comprise approximately 25% of the base color or aniline dye, about 60% of carbon black, and 15% of a toning blue pigment such as the Prussian blue commercially known as X-712. Both the carbon black and had a high oil absorption value. Similar vehicles were used in both compositions, comprising nondrying oils of animal, vegetable, or mineral origin. The two coatings may contain vehicle and coloring matter in the same proportions, such as 2 lbs. of a non-drying vegetable oil to 1 lb. of coloring matter. The tape employed was the ordinary typewriter cloth of long fiber Egyptian cotton with a thread count of 304 threads to the square inch. A dozen ribbons received a coating comprising about one ounce of ink on the light portion and about two ounces of ink on the heavy portion or a total quantity of three ounces of ink per dozen ribbons. In comparison, with ordinary ribbons having uniform inkings for the entire width, about two ounce-8' wou d be employed.

Further, the compositions for the upper and lower strips may be quite difierent. The above mentioned position maybe employed for the lower or reservoir strip in the proportion of two pounds of oil to one pound of coloring matter: while the upper or normal typing strip may have its coating comprised of as much as six or eight pounds of oil to one pound of a mixture of 45% of the base color, 45% of carbon black, and 10% of the toning pigment. As before, it is preferred to have a much heavier deposit upon the reservoir strip than upon the normal typing strip, as this aifords opportunity for a better action of the lower strip as a reservoir upon exhaustion of the upper strip, and a continuance of the typing with substantially the same degree of blackness for a long period of time.

The quantity of ink employed at the upper or light side may be varied according to the degree of ink (and hence lightness or darkness of the impression desired). The inking of the heavy or lower side remains substantially constant, so that maximum reservoir capacity is obtained. In some instances it is desirable to employ the vehicle without coloring material in the usual sense, but with a substantially colorless absorbent which likewise holds the vehicle and sur renders it as needed by the typing strip.

It is obvious that the invention is not limited to the employment of any particular pigments or ink materials, so long as the deposit upon one strip 11 is lighter than the deposit upon the other strip 12, and the relationship of the coatings is such that the strip 11 in normal storage resists the penetration by capillary transfer of 3% ink material from the strip 12, but upon tenta= tive exhaustion by employment or by the drying of the vehicle in the strip 11, this transfer takes place.

Having thus described the invention, what I thereof and a relatively heavy ink deposit of a 3% pigment of the same color and having a high oil-absorption value along a strip adjacent thereto, said heavy ink deposit serving as a reservoir to maintain the moistness of the light ink deposit as said light deposit becomes exhausted by drying or use.

2. A printing ribbon having two adjacent lengthwise strips of ink deposit thereon, one strip comprising a relatively light deposit and the other a relatively heavy deposit of ink materials of the same color.

3. A spool of typewriter ribbon comprising a spool and a ribbon thereon, said ribbon having two adjacent lengthwise strips of ink deposit thereon providing two individual portions for type impact, the upper strip comprising a lightdeposit and the lower a heavy deposit of ink materials of the same color.

4. A printing ribbon having two adjacent lengthwise strips of ink deposit thereon, one strip comprising a relatively light deposit of ink materials substantially free of moisture absorbent material, and the other strip comprising a relatively heavy deposit of ink materials containing a moisture absorbent materiai.

5. A printing ribbon having adjacent parallel strips with deposits thereon of different vehicle content, the normal typing strip including coloring matter, and the other strip being a reservoir strip including an absorbent for the vehicle and containing more vehicle than the typing strip.

6. A printing ribbon having adjacent parallel strips of ink deposit thereon, one strip being the normal typing strip and comprising ink materials substantially free of moisture absorbent material, and theother strip being a reservoir strip containing ink vehicle and a moisture absorbent material.

'7. A printing ribbon having adjacent parallel

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