US3223030A - Apparatus for drying printing colors - Google Patents

Description

Dec. 14, 1965 w. RAlNER 3,2

APPARATUS FOR DRYING PRINTING COLbRS Filed Oct. 8, 1962 2 Sheets-Sheet 1 r xxxyxxxxx x x xxxxxxyxxxxxxvx XXXXXAXXXXX HUM F. :t E.

' INVENTOR Mam-6 Emma A 77'OPIYEYS United States Patent Ofifice 3,223,030 Patented Dec. 14, 1965 3,223,030 APPARATUS FOR DRYING PRINTING COLORS Walter Rainer, Dornhirn, Austria, assignor to Heberlein Patent Corporation, New York, N.Y., a corporation of New York Filed Oct. 8, 1962, Ser. No. 228,881 1 Claims priority, application Austria, Oct. 27, 1961,

A 8,111/61 4 Claims. (Cl. 101-115) This invention relates to screen printing machines and tables and more particularly to apparatus for drying printing colors.

. Two primary methods are employed for screen printing colors upon a web of fabric or sheet material. In one method elongated stationary tables are utilized upon which the material to be printed is positioned. One or more screens are movably mounted over the table so that they print in pattern repeats upon the web of fabric. When multi-colored patterns are being produced, the process is repeated with a corresponding number of screens so that one screen is employed for each color to be printed.

Another type of screen printing machine, which is employed frequently, utilizes the principle, whereby, the web of fabric or sheet material is advanced in steps over a printing base member or table while the screens remain stationary thereover. A series of pattern repeats are printed upon the web and each step of advancement of the web over the printing base member corresponds to a single complete pattern.

. Persons skilled in the art will readily realize the importance and the necessity of drying the colors after they have been printed upon the web of material. If the color of one repeat is not completely dry before the next adjacent repeat is printed upon the web, then the colors tend to bleed or contaminate each other in an undesirable manner. Further, when a multi-colored pattern is being produced the color from the first printing must be dry before the second color is printed thereover, or else difficulty will be experienced due to the inter action of the two colors. This is particularly important because, if the first color is not set or dryed, the printed pattern will tend to lose its sharpness of outline or contour when the second or overprint is made. It is to be noted that the solvents in the second color tend to cause the first color to run when the first color has not been allowed suflicient time to dry. As a further problem the wet color that remains upon the web may adhere to the screen and be improperly imprinted at another, undesirable location upon the fabric.

Heretofore, in order to overcome the aforementioned problems, space was provided between the individual pattern printings. This space would correspond to one or two pattern repeats which would be added at a later time after the wet color had been allowed to dry. This, of course, required a considerable amount of waiting time and prompted the necessity of providing large, elongated printing tables or base members. From an economical and commercial viewpoint, faster drying methods became very desirable, instead of relying upon the temperature and humidity prevailing in the printing room.

Heretofore, it has been proposed to inject heated air by means of circulation, either into the chamber or directly onto the web of material. Another method which has been proposed consisted of providing a drying cart which followed along the edge of the printing tables. However, such a cart may only be used Where the rails for printing carts are installed. Among other disadvantages these solutions were not practical from economical considerations.

Further, apparatus for drying printing colors have been known to utilize infra-red radiators which were mounted above the printing table. The disadvantage with this system is that the workers are constantly exposed to heat radiation. Further, certain colors tend to gel when thus irradiated and their quality is thereby impaired. Radiators which heat the printing tables have been employed, but they create uneven drying patterns whereby various locations of the web of fabric dry with varying rates of speed.

In general prior art devices have not been particularly effective. They tend to be uneconomical and inefiicient. Further, such installations generally cause excessively high room temperatures which has a detrimental effect on the performance of the operating personnel.

In order to overcome the foregoing salient problems, I have invented a novel apparatus for drying printing colors which comprises a heating mat interposed between the web of material and the base member. The heating mat is a laminar structure which is both flexible and resilient so that the usual printing felt may be dispensed with, if desired. One of the layers comprises a heating element, preferably of the electrical-resistance type. A protective abrasion-resistant layer is disposed adjacent the web of fabric in order to increase the longevity of the heating element and to aid in dispensing the heat in a uniform and even manner. A heat insulating layer is provided underlying the heat-ing element in order to reduce extraneous heat losses. Further, an aluminium foil may be positioned underlying the heat insulating layer for reducing heat radiation losses.

There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of the invention.

Specific embodiments of the invention have been chosen for purposes of illustration and description, and are shown in the accompanying drawings, forming a part of the specification, wherein:

FIG. 1 is a side elevation showing an apparatus for drying printing colors constructed in accordance with my inventive concept;

FIG. 2 is a perspective view showing a printing table having a blanket, heating mat, and printing felt thereon;

FIG. 3 is a vertical sectional view showing the printing table and heating mat thereon;

FIG. 4 is an enlarged vertical sectional view showing the details of the heating mat constructed in accordance with one embodiment of my invention;

FIG. 5 is an enlarged vertical section showing another embodiment of the heating mat;

FIG. 6 is a plan view showing one embodiment of a heating element;

FIG. 7 is a plan view showing another embodiment of a heating element;

FIG. 8 is an enlarged sectional view taken along line 88 of FIG. 7.

Referring now to the drawings in more detail and particularly to FIG. 1, there is shown an apparatus for drying printing colors in which a web 10 of fabric or sheet material is fed into the machine from a convenient outside source (not shown). The completed or finished web of fabric is discharged from the opposite end of the apparatus after the printing and drying processes have been completed.

A plurality of printing base members 12, 14, 16 and 18 are mounted in spaced relationship one to the other. Directly overlying the printing bases and firmly adhered thereto are a corresponding plurality of plates 20, 22, 24 and 26, respectively. Disposed above the plates is a heating mat 28. Generally, one heating mat is of sufiic ient length to overlay or cover a plurality of plates, as shown. Interposed between the heating mat 28 and the web of fabric 10 is a movable endless belt or blanket 30. The belt is adapted to pass over rolls 32 and 34 which are positioned in fixed space relationship one to the other. Rolls 32 and 34 are suitably mounted upon shafts 36 and 38, respectively, for rotation, and one of the shafts is driven by outside motive means (not shown). Positioned above each printing base 12, 14, 16 and 18 are a plurality of stationary screens 40, 42, 44 and 46', respectively. Each stationary screen is supplied with color which is to be printed upon the web of fabric as it passes thereunder. The belt 30 is adapted to carry the web of fabric 10 between the screens and their respective printing bases. Usually, the web 1 is advanced in steps corresponding to the linear length of each complete pattern, and as the web passes beneath each screen it is imprinted with a portion of the pattern. Several different arrangements may be employed with the various screens, for example, if a simple one-color pattern is desired the screen 40 may print the first complete pattern, screen 42 prints the third complete pattern spaced apart from the first pattern, screen 44 prints the fifth pattern spaced apart from the third pattern and screen 46 prints the second pattern between the first and third pattern, and so forth. Thus, suflicient time is allowed to elapse between the printing of two adjacent patterns for the colors to dry. As another example, screen 40 may print one color while screens 42, 44 and 46 print additional colors upon the same pattern and, thus, produce a multi-colored design.

Referring now in particular to FIG. 2, the web of material 10 to be printed overlays the blanket or belt 30. It is to be noted that the belting material and caliper thereof are such that heat may be transferred therethrough. Rubber or the like material may be employed. The heating mat 28 is disposed adjacent the belt in an underlying position, the details of which will be more fully described hereinafter. Interposed between plate 20 and the heating mat 28 is a printing felt layer 48. This layer is intended to absorb the shock forces when the screens print upon the web of fabric. Under some circumstances, especially when the heating mat is sufficiently resilient, the felt layer may be dispensed with. A printing table or firm printing base 12 is employed to support the plate 20 as shown.

FIG. 3 is a vertical sectional view showing the printing table 12 and the heating mat 28 disposed thereon. Electrical terminal connection 50 is provided for energizing the electrical heating mat 28 from standard commercially available power sources. FIGS. 4 and illustrate the heating mat itself which comprises a plurality of layers. The heating element 52 is interposed between an abrasion resistant layer 54 and a heat insulating layer 56. The abrasion resistant layer 54 may .comprise a thin plastic film which is applied by means of spraying. The choice of the type of plastic depends upon the required temperature stability due to the fact that it is in contact with the heating element 52 which has a temperature range in the order of 390 to 575 degrees Fahrenheit. If desired, finely divided metallic particles may be admixed with the plastic for temperature stability purposes as well as improving the heat conduction. Since the upper surface of this layer is in contact with the moving belt it is desirable that the surface be smooth and abrasion resistant. Preferably, the thickness of this layer is in the order of .019 to .024 inch. The heat insulating layer 56 may be manufactured from a glass fiber netting. The twill binding found in such material provides good pliability and the fiber glass material has a low heat conduction rate. This layer, also, acts as a heat reservoir and improves the uniform dispersion of the heat from the heating element to the web of fabric. Further, glass fiber provides adequate mechanical strength. Preferably, the thickness of this layer is .007 to .008 inch. In order to prevent heat radiation downwardly, a reflecting layer 58 may be provided underlying the heat insulating layer- A um num f i v n a th k ess n he rder of .004 inch may be employed for this purpose.

According to the concept of my invention, the heating element 52 may assume various forms as illustrated in FIGS. 6, 7 and 8. FIG. 6 shows three longitudinally extending adjacent metallic strips 60, 62 and 64, each of which is connected to one phase of a three phase alternating current supply as shown at 66, 68 and 70 respectively. The opposite ends of the strips are each connected to a common ground connection 72, thus, forming an electrical resistance heater. FIG. 7 illustrates a heating element comprising a plurality of metal and fiber Wires or threads making a netting or screenlike pattern. Various weaving patterns may be employed, for example, the warp threads may consist of groups of metallic conducting Wires and the weft threads may consist of nonmetallic or inorganic fibrous material. The fibrous materials act as electrical insulation as Well as providing a heat insulating layer. Strips or groupings of Wires 74, 76 and 78 are each made up from a plurality of individual wires 80. Each grouping of wires are connected to one phase of a three phase electrical supply source 82, 84 and 86, respectively. The opposite ends of the groups of wires are interconnected to a common ground connection 88. Within the concept of my invention, there are many methods by which the conducting and non-conducting threads or wires may be interrelated. FIG. 8 illustrates a Weave showing conductive wires 80 intermingled with non-conductive threads 90. With this type of heating apparatus, it is possible under certain circumstances to omit the separate heat insulating layer 56 mentioned heretofore. Preferably, the thickness of the heating element is in the order of .007 to .008 inch.

In view of the foregoing, it is seen that the heating mat is resistant to pressure, resilient and flexible, thus undesirable bulges or folds are not encountered therein.

Although particular embodiments of the invention are herein disclosed for purposes of explanation, further modifications thereof,'after study of this specification, will be apparent to those skilled in the art to which the invention pertains. Reference should accordingly be had to the appended claims in determining the scope of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. A screen printing device comprising a base means extending along a given path and adapted to support an elongated web of material to be printed, a plurality of screen printing members spaced .along said path and each of which is positioned to print upon the web of material passing over said base means, motive means arranged to move the web of material along said base means and said screen members, and a flexible resilient mat coextensive with said base means and lying on the surface of said base means for supporting said web, the resiliency of said mat being such that it absorbs the shock forces which occur when the screen member prints upon the web, said flexible resilient mat including, as a lamination thereof, an electrical resistance heater of fabric-like material.

2. A screen printing device comprising a base means extending along a given path and adapted to support an elongated Web of material to be printed, a plurality of screen printing members spaced along said path and each of which is'positioned to print upon the web of material passing over said base means, motive means arranged to move the web of material along said base means and said screen members, and a flexible resilient mat coextensive with said base means and lying on the surface of said base means for supporting said web, the resiliency of said mat being such that it absorbs the shock forces which occur when the screen member prints upon the web, said flexible resilient mat including, as a lamination thereof, an electrical resistance heater of fabriclike material and further including, as another lamination thereof, a heat insulating layer between said electrical resistance heater and said base means.

3. A screen printing device comprising a base means extending along a given path and adapted to support an elongated web of material to be printed, a plurality of screen printing members spaced along said path and each of which is positioned to print upon the web of material passing over said base means, motive means arranged to move the web of material along said base means and said screen members, and a flexible resilient mat coextensive with said base means and lying on the surface of said base means for supporting said web, the resiliency of said mat being such that it absorbs the shock forces which occur when the screen member prints upon the web, said flexible resilient mat including, as a lamination thereof, an electrical resistance heater of fabric-like material and further including as another lamination thereof, a. heat reflecting layer interposed between said electrical resistance heater and said base means.

4. A screen printing device comprising a base means extending along a given path and adapted to support an elongated web of material to be printed, a plurality of screen printing members spaced along said path and each of which is positioned to print upon the web of material passing over said base means, motive means arranged to move the web of material along said base means and said screen members, and a flexible resilient mat coextensive with said base means and lying on the surface of said base means for supporting said web, the resiliency of said mat being such that it absorbs the shock forces which occur when the screen member prints upon the Web, said flexible resilient mat including, as a lamination thereof, an electrical resistance heater of fabriclike material having conductive wires interposed between non-conductive threads and further including as another lamination thereof, a flexible resilient layer between said electrical resistance heater and said base means.

References Cited by the Examiner UNITED STATES PATENTS 2,412,843 12/1946 Spraragen 219S 2,623,464- 12/1952 Rodenburg et a1. 10'1126 X 2,634,361 4/ 1953 Reynolds 2l9345 2,758,540 8/1956 Laupman 101-126 EUGENE R. CAPOZIO, Primary Examiner.

ROBERT E. PULFREY, Examiner.

Claims (1)

1. A SCREEN PRINTING DEVICE COMPRISING A BASE MEANS EXTENDING ALONG A GIVEN PATH AND ADAPTED TO SUPPORT AN ELONGATED WEB OF MATERIAL TO BE PRINTED, A PLURALITY OF SCREEN PRINTING MEMBERS SPACED ALONG SAID PATH AND EACH OF WHICH IS POSITIONED TO PRINT UPON THE WEB OF MATERIAL PASSING OVER SAID BASE MEANS, MOTIVE MEANS ARRANGED TO MOVE THE WEB OF MATERIAL ALONG SAID BASE MEANS AND SAID SCREEN MEMBERS, AND A FLEXIBLE RESILIENT MAT COEXTENSIVE WITH SAID BASE MEANS AND LYING ON THE SURFACE OF SAID BASE MEANS FOR SUPPORTING SAID WEB, THE RESILIENCY OF SAID MAT BEING SUCH THAT ITS ABSORBS THE SHOCK FORCES WHICH OCCURS WHEN THE SCREEN MEMBER PRINTS UPON THE WEB, SAID FLEXIBLE RESILIENT MAT INCLUDING, AS A LAMINATION THEREOF, AN ELECTRICAL RESISTANCE HEATER OF FABRIC-LIKE MATERIAL.

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