Abstract:
This invention is related to a printer and printing method that prints on recording media with water soluble ink by using an ink jet printer. It is related to the printing method that can create printed images with supreme durability especially on recording media or stiff panels of different thickness with water absorbent surfaces, like wood boards, porous plastic boards, and the like, and on a recording media with water resistant surfaces, like plastic boards, glass or metal plates and the like, to which an emulsion adhesive layer is applied for a printing layer. The printer of the invention has features enabling movement past the print head of media of different thickness and formed as panels while the image surfaces of the panels are vertically properly spaced from the print head for printing.

Description:
BACKGROUND OF THE INVENTION 
     Various objects such as compact disc surface, and the like, besides general recording papers can be used as printing objects of an ink jet printer. The owner of the present application previously proposed a printer that placed recording media like CD, or the like, on a medium transporting tray and transported the medium transporting tray through the printing position of an ink jet head in order to print on the surfaces of the CD by using an ink jet printer. 
     Since ink jet printers generally use water soluble ink, they cannot use the materials that do not accept water soluble ink as recording media. For example, if the ink jet printer prints on the surfaces of highly water absorbent surface like wood, and the like, ink solution will be absorbed by wood and the printed image cannot be preserved on the wood surface. On the other hand, if the ink jet printer prints on a recording medium with a water resistant surface such as plastic boards, glass or the like, ink solution cannot be absorbed at all because of surface tension. Therefore, the printed image will be printed weakly on the surface of such recording medium and will be peeled off easily. 
     SUMMARY OF THE INVENTION 
     An object of this invention is to provide an ink jet printer and a printing method using an ink jet printer that can create highly permanent and durable printed images on highly water absorbent wood and other absorbent panels. 
     Another object of this invention is to provide a printer and printing method using an ink jet printer that can create highly permanent and durable printed images on highly water resistant recording media like plastic boards, glass panels and other water resistant panels. 
     In order to solve the above objects, this invention involves a printer and a printing method using an ink jet printer with features of creating an image receiving layer on the printing surface by applying emulsion adhesive on the printing surface of a recording medium and then creating printed images with water soluble ink on the surface of the image receiving layer by using an ink jet head or other equivalent ink type printers. 
     The image receiving layer created by emulsion adhesive is most adequate for the printing surface for water soluble ink and can obtain extremely permanent printed images. Therefore, it enables the printing on highly water absorbent recording media wood panels, and the like, as well as water resistant media such as plastic panels, and the like. 
     For printing panels for objects such as outdoor billboards, and the like, it is desirable to create a ultraviolet resistant layer by applying UV blocking agent such as xylene solution, or other agent, on the surface of the said image receiving surface after printed images are created in order to improve weather resistance of printed images. 
     Also, in order to improve durability of printed images, after the printed images are created, it is desirable to create a protection layer of resin paint on the surfaces of the printed images or on the surface of the ultraviolet resistant layer. 
     This invention has a feature of creating the said image receiving surface by using emulsion adhesive with water resistant water paint. It also has a feature of creating the said image receiving surface by using emulsion adhesive with surfactant. 
     Such an image receiving layer has supreme adherence or stability for water resistant surfaces like plastic boards and metal plates, and the like. Therefore, highly permanent printed images can be created on the surface of highly water resistant materials by creating the printed images on this image receiving layer with water soluble ink. 
     Also, this invention has a feature of creating the said image receiving layer by using emulsion adhesive with coloring components like cosmetics, dyes, and golden or silver powder, and the like. Also, the invention has a feature of creating the said image receiving layer by using emulsion adhesive with fragrance. 
     An ink jet printer for the printing method of this invention transports a medium of different thickness by transporting means, which include in one form a transporting tray carrying a recording medium through the printing position of a printing head which prints on the surface of the said recording medium. It is desirable to use ink jet printers that have a transporting connection part to transport this medium transporting medium through the said printing position by rubbing against or biting into the said medium or a transporting tray and an interval adjustment mechanism to move the medium relative to the printing head in a direction closer to or further from the said printing head. With such a printer, the printing can be done on panels of wood and plastic or metal panels of different thicknesses, as well as printing on general recording papers. 
     The invention, including the printer and the method of printing will be hereinafter described in relation to the drawings forming a part of this application. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top plan of the ink jet printer of this invention; 
     FIG. 2 is a side view on the line II—II of the ink jet printer in FIG. 1; 
     FIG. 3 is a cross section in the line III—III of the ink jet printer in FIG. 1; 
     FIG. 4 is a perspective of the medium transporting tray of the ink jet printer in FIG. 1; 
     FIG. 5 is a perspective view showing the medium transporting tray of the ink jet printer in FIG. 1; 
     FIG. 6 is a view showing the side construction of the medium transporting tray of the ink jet printer in FIG. 1; and 
     FIG. 7 is a view showing the printing method of this invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     An example of ink jet printers that are adequate for the printing method described below will be explained. 
     As seen in the drawings, referring first to FIGS. 1 through 3, the ink jet printer  1  of this example has a raised frame  2  of suitable height, an ink jet head unit  3  located almost at the center of the top of this frame, a paper feeding side tray guide  4  located on the paper feeding side of this head unit  3 , a paper ejecting side tray guide  5  located on the paper ejecting side of the head unit  3 , and a tray transporting means or unit  6  located between the head unit  3  and the paper feeding side tray guide  5 . Also, it has a medium transporting tray  7  that moves back and forth along the transporting path through the font position  31  of the head unit  3  by this transporting unit  6 . If desired or preferred, the transport may be of another type using feed rollers and means for aligning the media while permitting vertical adjustment of the space between the print head and the transported media. 
     FIG. 4 is a perspective that shows a medium transporting tray. As indicated in FIG. 4, the medium transporting tray  7  has a square board  71  with specific thickness and sprocket holes  72  and  73  that are placed in lines toward a transporting direction along both sides of this square board. The area surrounded by a dotted line on the flat surface of the square board  71  is a receiving surface  74  for a recording medium. A recording medium  8  such as a thick wood board or a thick plastic panel, and the like, is placed on this receiving surface  74 . 
     FIGS. 5 and 6 are a perspective and a side elevation that indicate outlined construction of a tray transporting unit  6 . By referring to these Figs., it will be seen that the tray transporting unit  6  has a pair of sprockets  61  and  62  that can engage in the sprocket holes  72  and  73  on both sides of a medium transporting unit  7  and an interval adjustment mechanism  10  that moves these sprockets  61  and  62  to a position closer to or away from the nozzle surface  33  (see FIG. 2) of an ink jet head  32  of a head unit  3  and a driving power transmitting mechanism  9  that rotates the pair of sprockets  61  and  62 . 
     The sprocket  61  of this example is composed of a pair of gears  63  and  64 , a belt with gears  65  that is placed over these gears, and protruding pins  66  created at a certain interval on the outer circumference of this belt with gears  65 . The belt with gears  65  is hung toward the transporting direction of the medium transporting tray as it draws along an oval loop. The sprocket  62  also has the same structure and has a pair of gears  67  and  68  and a protruding pin  70  on the outer circumference of this belt with gears  69 . A flat outer run on the top of these pairs of belts with gears  65  and  69  regulates the height of the transporting surface of the medium tray and, therefore, the position of a medium relative to the print head. 
     An interval adjustment mechanism  10  has a common rotating shaft  11  that is for the gears  63  and  67  of each sprocket  61  and  62  and a common rotating shaft  12  for other gears  64  and  68  of each sprocket  61  and  62 . These rotating shafts  11  and  12  are supported to rotate freely by a supporting means  13 . The supporting means  13  has a bottom plate  131  and side plates  132  and  133  that stand perpendicularly at both sides of this bottom plate  131 . Rotating shafts  11  and  12  are placed horizontally and parallel to a perpendicular direction of the transporting direction between both side plates  132  and  133 . 
     The center of the bottom plate  131  is supported by an elevating means  14 . The elevating means  14  has side plates  143  and  144  with horizontal notches  141  and  142  into which the bottom plate  131  of support  13  can be inserted from the horizontal direction and a flat bottom board plate that connects bottom sides of these side plates  143  and  144 . 
     Also, one rotating shaft  145  is placed on the top of the horizontal notches  141  and  142  between the side plates  143  and  144 . Top supporting rollers  146  and  147  are placed on both sides of this rotating shaft  145  to rotate freely. Two rotating shafts  148  and  149  are placed horizontally on the bottom of the notches  141  and  142  between the side plates  143  and  144  and bottom supporting rollers  151 ,  152  and  153 ,  154  are placed on both sides of each rotating shaft  148  and  149  to rotate freely. 
     The bottom plate  131  of the supporting means that is inserted horizontally into the flat notches  141  and  142  on the side plates  143  and  144  is held by the top supporting rollers  146  and  147  and the bottom supporting rollers  151 ,  152  and  153 ,  154 . Therefore, it can elevate the supporting board  13  to slide horizontally. 
     One of the side plates  143  of the elevating means  14  has a part  156  that is extended to the bottom. A perpendicular rack  16  is formed on this part. This rack  16  engages a pinion  17  and this pinion  17  is mounted to the output shaft  181  of an elevating stepping motor  18 . 
     Therefore, when the stepping motor  18  is activated, the elevating means  14  is elevated or lowered, the supporting means  13  is also elevated or lowered and the sprockets  61  and  62  of the rotating shafts  11  and  12  on this supporting means  13  will also be elevated. As a result of the above described means, the distance between the transporting surface of the medium transporting tray that is regulated by these sprockets  61  and  62  and the ink jet head  32  of the head unit  3  will be increased or decreased. Equivalently, the head may be moved vertically toward and away from the transporting means. 
     A drive transmitting mechanism rotates the sprockets  61  and  62  and includes one side of the rotating shaft  11  of the sprockets  61  and  62 , a drive gear  19  fixed on the same shaft. This drive gear  19  engages a driving gear  20  that is placed on the side of a raised frame  2 . The driving gear  20  is connected to a motor (not indicated in the figure) through a decelerating gear row  21 . Therefore, when the driving motor is activated, the rotating shaft  11  rotates through the driving gear  20  and the following gear  19  and the sprockets  61  and  62  also rotate as one unit to transport the medium transporting tray  7  on these sprockets  61  and  62 . 
     Now, both sides of two rotating shafts  11  and  12  extend outward horizontally through the side plates  132  and  133  on both sides of the supporting means  13 . A guide  22  that has arched slots  221  and  222  and a guide  23  that arched slots  231  and  232  are placed on the outside of the side plates  132  and  133 . Both sides of the rotating shafts  11  and  12  extend through  221 ,  231 , and  222 ,  232  of each guide  22  and  23 . 
     As explained well in FIG. 6, the elevating gear  19  engages the driving gear  20  that is located in a fixed position. In order to always engage the gear  19  with the driving gear  20 , the gear  19  needs to be elevated along a circle trace  19   a  that surrounds the center of the rotation  20   a  of the driving gear  20 . In this example, the rotating shafts  11  and  12  slide along the arched slots  221 ,  231 , and  222 ,  232  along this arc  20   b.    
     Now, in order to elevate the rotating shafts  11  and  12  along the arched notches, they need to move horizontally as they move through arc  20   b . In this example, as mentioned earlier, the rotating shafts  11  and  12  support the supporting means  13  to slide horizontally by the elevating means  14  with the top supporting rollers  146  and  147  and the bottom supporting rollers  151 ,  152 , and  153 ,  154 . Therefore, the gear  19  can be elevated while engaging with the driving gear  20 . 
     Next, the ink jet printer  1  of this example elevates flat beds  4  and  5  along with the elevation of the sprockets  61  and  62 . As a result, the transporting side that is regulated by the sprockets  61  and  62  and the transporting side of the medium transporting tray  7  by the flat beds  4  and  5  are placed on the same side. 
     By referring to FIG. 1 or  3 , each flat bed  4  and  5  has tray guides  41 ,  42 , and  51 ,  52  that guide the side of the medium transporting tray  7  on both sides. Also, the flat beds have multiple numbers of rollers  43  and  53  that regulate the transporting side of the medium transporting tray  7 . The horizontal support frames  45  and  55  for the rotating shafts  44  and  54  that support rollers  43  and  53  to rotate freely are supported by perpendicular linear guides  46  and  56  to be elevated. The horizontal support frames  45  and  55  have brackets  47  and  57  that are extended to the bottom. The racks  48  and  58  are perpendicularly placed on these brackets  47  and  57 . The pinions  50  and  60  that are placed on the output shaft of each bed elevating motor  49  and  59  engage each rack  48  and  58 . 
     When the motors  49  and  59  are activated, the horizontal support frames  45  and  55  can be elevated. In this example, by activating the elevating motor  18  along with the driving of the motors  49  and  59  of the tray transporting unit  6 , the tray transporting side that is always regulated by the sprockets  61  and  62  and the tray transporting side that is regulated by each flat bed  4  and  5  are placed at the same height. 
     As explained above, the ink jet printer  1  of this example can print on the recording medium  8  on the medium transporting tray by moving the medium transporting tray  7  back and forth through the font position of the print head. Since the medium transporting tray  7  is transported by the sprockets  61  and  62 , this printer can easily transport heavier recording media than a friction type transporting mechanism using general paper sending rollers can transport, but general paper sending rollers may be adequate for some light weight media of different thickness. 
     Also, according to the thickness of the recording medium  8  to be put on the medium transporting tray  7 , a gap between the recording medium  8  to be transported and the nozzle side  33  of the ink jet head  32  can and should be maintained at constant distance. Therefore, thick recording media of different thicknesses can be printed. 
     Furthermore, in this example, the printer has the flat beds  4  and  5  located in front and back of the transporting direction. These flat beds elevate along with the sprockets  61  and  62  as one unit. Therefore, these flat beds  4  and  5  can support the medium transporting tray  7  to transport a long medium transporting tray  7 . 
     FIG. 7 explains the printing method that creates printed images with water soluble ink on the surfaces of water absorbent recording media such as wood boards, and the like by using ink jet printers. Referring to FIG. 7, first of all, prepare a water absorbent recording medium  8  as indicated in FIG.  7 ( a ) and apply resin such as acetic acid vinyl emulsion, or the like, on this printing surface  81 . This resin contains the same ingredients as commercially-sold adhesive as wood craft bond. It changes into a transparent resin layer when it is dried. The adhesive creates an image receiving layer  82  on the printing surface  81 . Any emulsion adhesive besides acetic acid vinyl emulsion can be used. 
     After the image receiving layer  82  is dried, a desirable printed image  83  can be created with water soluble ink on the surface of this image receiving layer  82  by using an ink jet printer as indicated in FIG.  7 ( c ). 
     After printing, a ultraviolet ray resistant layer  84  is created on the surface of the printed image  83  by applying UV cut ingredient such as xylene solution, and the like as indicated in FIG.  7 ( d ). Furthermore, a protection layer  85  of resin paint is created on the surface of the ultraviolet ray resistant layer  84  as indicated in FIG.  7 ( e ). 
     As explained above, the printing method of this example can achieve durable and weather resistant printing with water soluble ink on the surfaces such as wood, and the like. Therefore, outdoor billboards, and the like can be printed easily and economically. 
     Now, if an image receiving layer  82  is created by using emulsion adhesive with coloring components such as cosmetics, dyes, and golden powder, and the like, base color of the printing surface can be chosen freely. Also, by mixing golden powder and silver powder, a variety of designs can be achieved on the printing surfaces. Furthermore, if the image receiving layer is created by using emulsion adhesive with fragrance, the printed materials that can appeal to both vision and smell can be materialized. 
     On the contrary, in order to adequately print on water resistant surfaces, for example, metal surface, plastic surface, and glass surface, and the like, the said image receiving surface  82  can be created by using emulsion adhesive with water resistant water soluble paint. 
     In addition, or separately, an image receiving surface  82  can be created by using emulsion adhesive with surfactant. 
     Also in this case, if the image receiving layer  82  is created by using emulsion adhesive with coloring components such as cosmetics, dyes, and golden or silver powder, and the like, base color of the printing surface can be chosen freely. Also, by mixing golden powder and silver powder, a variety of designs can be achieved on the printing surfaces. Furthermore, if the image receiving layer is created by using emulsion adhesive with fragrance, the printed materials that can appeal to both vision and smell can be materialized. 
     Of course, general ink type printers other than the said ink jet printers can also be used for the printing method of this invention. 
     As explained above, the printing method using an ink jet printer of this invention creates the image receiving surface that is adequate for the printing with water soluble ink by applying emulsion adhesive on the surface of the water absorbent, recording media. Therefore, an ink jet printer can be used to create permanent and durable printed images with water soluble ink on the surfaces like wood boards, porous plastic boards, and the like, of different thicknesses. 
     Also, the printing method of this invention creates an image receiving surface that is adequate for the printing with water soluble ink by applying emulsion adhesive with water resistant water soluble paint or applying emulsion adhesive with surfactant on the surface of the water resistant recording media. Therefore, durable printed images with water soluble ink that will not be peeled off can be created on the surfaces like plastic, metal, and glass, and the like, of different thicknesses by using ink jet printers.