JPS5995157A - Head for bubble driven ink jet printer - Google Patents

Abstract

PURPOSE:To obtain a structure for easily preparing a head, by providing a means for generating air bubblers in ink on an orifice plate. CONSTITUTION:A layer 29 to be susceptible to deactivation is grown on a metal orifice plate 27 provided with orifices 23, 25. After deactivation, resistances 13, 15 and conducters 17, 19 are formed on the deactivated layer 29 by usual membrane technique and a second layer 30 to be susceptible to deactivation 30 is applied to the surface so as to cover the resistances and the conductors. A spacer layer 31 with a pattern is applied to said second layer 30 to be susceptible to deactivation while a backing plate 35 provided with a manifold 39 is arranged on the spacer 31 and, by this structure, an ink capillary pipeline 43 for directing ink flow onto the resistances 13, 15 to complete a head. Various elements provided on the orifice plate can be easily arranged by using a usual mask matching apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bubble-driven ink jet printing head (hereinafter simply referred to as a head), and particularly to a head having a structure that is easy to manufacture.

U.S. applications and patents that provide technical background on bubble-driven ink jet printing include, for example, U.S. Patent Application No. 292,841 and U.S. Patent No. 4,240.
No. 3,994, No. 4,296,421, No. 4,251
, No. 824, No. 4,313,124, No. 4,325,
No. 735, No. 4.330, 787, No. 4.33423
No. 4, No. 4,335,389, No. 4.336,548
No. 4.338,611, No. 4,339.762, and No. 4.345,262. According to the basic concept disclosed in these documents, a head includes an ink-containing capillary, an orifice plate with an opening or orifice through which the ink is ejected, and an ink heating mechanism (typically a resistor) proximate to the orifice. ). In this operation, the ink heating mechanism heats up rapidly and transfers a significant amount of energy to the ink, thereby vaporizing a small amount of ink and creating bubbles within the capillary tube. This creates a pressure wave that causes a drop or drops of ink to be ejected from the orifice onto the recording body in its vicinity. By controlling the energy transfer to the ink, the bubble can be rapidly collapsed before the ink vapor exits the orifice.

However, in each of the prior art examples described above, the structure of the device typically consists of a composite component structure. Typically, resistors and conductors are first deposited onto the substrate. The orifice plate, which is separate from the substrate, is then attached to the substrate, and great care must be taken to ensure accurate alignment of the various components.

The present invention solves the problems of the prior art described above and provides a head having a structure that is easy to manufacture.

According to the present invention, a head with an orifice plate having a novel structure is provided. A heating element is provided on the orifice plate used here.

The elements provided on this orifice plate can be easily aligned using standard mask alignment equipment. In manufacturing this head, an orifice plate is first formed, which is typically a flat sheet member with orifices opened therein. Next, passivation layer (
1 ayer) is grown on this sheet. Resistors and conductors to power the resistors are then deposited onto the passivation layer using standard IC techniques. A spacer is then attached to the passivation layer. This spacer creates a capillary path for the ink to flow and increases the hydraulic impedance between the resistors. Thus, the head is completed by attaching a sheet member as a back plate from the spacer side to the orifice plate in which the necessary elements are monolithically formed. This sheet member serves as a lid for the capillary channel defined by the spacer.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a top view of an orifice plate resistance complex used in a head according to an embodiment of the present invention. Is it from Figure 1?
The orifice plate resistor complex has a monolithic
Resistors 13 and 15, conductors 17, 19 and 21, orifices 23 and 25 are provided. Unlike prior art head structures in which an orifice plate is attached to a substrate on which conductors and resistors are formed, in the present invention, resistors and the like are placed on the orifice plate. FIG. 2 illustrates an early stage in the manufacturing process of an orifice plate resistor composite.

This figure is a perspective view showing a cross section corresponding to the AA cross section in FIG. This Oriais resistance structure? ) - begins with a metal orifice plate 27 provided with orifices 23 and 25. Orifice plate 27 is preferably made by electroforming, but sheet material may also be used. Preferred metals for the orifice plate 27 are nickel, copper, beryllium-copper, titanium, molybdenum, the
American Iron 5teel In
3()0 series stainless steel specified by the standards of
1conductor Equipment Mate
(name used by realsIn3jitute).

0.0508 mm to 0.1016+n+++ (
2 mil to 4 mil). Orifices 23 and 25
can also be formed by etching or laser drilling. More preferably, however, the orifice is formed at the same time as the orifice plate is formed in the aforementioned electroforming process by using a non-conductive barrier that defines the shape of the orifice (November 1982).
(Refer to U.S. Application No. 443,980, filed on May 23rd),
A passivation layer 29 is grown on this orifice plate 27. The role of the passivation layer 29 is to provide electrical insulation and protect the orifice plate 27 from chemical attack, such as corrosion by the ink used. Typical materials used for passivation layer 29 include 5i02. SiOxNy, AJ
. 03 and TiO2. The thickness of passivation layer 29 typically ranges from 0.5 to 1.5 microns, although the preferred thickness depends on the thermal conductivity of the material selected.

After passivation, resistors 13 and 15 and acid gas conductors 17.19$5 and 21 are formed on passivation layer 29 by standard thin film techniques. Typically, resistors 13 and 15, resistors 13 and 15, can have a crowded range of resistance. However, a preferred resistor line is approximately 60 Ω, and the surface dimensions of the resistor are approximately 0.0635 x O, 1524 mm (2,5
mil x 6 mil).

After depositing the resistors and conductors, a second passivation layer 30 is applied over the resistors and conductors by standard techniques to provide electrical isolation and protection against cavitation. give.

Next, a patterned spacer layer 3 with a thickness in the range of 1.5 to 5 mils (preferably about 2 mils).
is applied to the second passivation layer 30 (see FIGS. 1 and 3). Typical materials for patterned spacers/i'f31 include Vacrel or) Lis
ton (both registered trademarks of DuPont), solder glass
), screened glass grain-filled epoxy
glass bead f-eye led, epoxy L
Polyimide and even electroplated metal can be used.

The purpose of the patterned spacer layer 31I/) is to provide a capillary path for directing the flow of ink onto the resistors 13 and 15 and also to provide a tongue-like separator 33 between the orifices 23 and 25 to The goal is to mechanically separate both orifices to some extent, thereby avoiding cross-talk during operation. The direction of ink flow is illustrated by the numbered arrows in FIG. A suitable back 35, such as that shown in FIG. 4, is then rigidly attached to the patterned spacer layer 31. This accommodates ink and provides an ink supply port 37.

Typically, for optimal operation, backplate 35 is provided with an ink manifold 39 at 5, as shown in FIGS. It's accumulating.

FIG. 5 shows a CC sectional view of the back plate 35.

The material of the back plate 35 is the patterned spacer layer 31.
Almost any material can be used as long as it can be attached and molded to the material. However, since it is better to provide the back plate with a manifold, the material for the back plate is preferably one that has a high degree of freedom in molding, such as metal or plastic. In Figure 5 etc., the back plate 3
Although the thickness of 5 is shown as being uniform, such uniformity of thickness is not necessary. That is, if, for example, the back plate is also used as a reinforcing material or a bottle body, the thickness of each part may vary considerably depending on the mechanical properties required for that purpose.

A sectional view of the head constructed as described above is shown in FIG. 8. This figure is a sectional view of the head viewed from the B-Bll'i plane, not shown in FIGS. 1 and 4.

A back plate 35 with a manifold 39 is placed over the spacer 31 as shown in FIG. 6, thereby forming an ink capillary channel 43. A typical distance between the center point of resistor 13 and the point closest to the resistor on manifold 39 is approximately 0.508 mm (20 mils);
Typical values for the height 'r of 9 are in the range of +1.0635 nm to 0.127 in (2.5 mils to 5 mils). Similarly, the center point of the resistor 13 and the orifice 23
The distance F between the center point of is approximately 0.254 vnm to 1), 508 mm (10 mils to 20 mils). The second passivation layer 30 is also best seen from the orientation of this figure.

FIG. 7 is a drawing of the head of the present invention as viewed from the side from which ink is ejected, and orifices 23 and 25 are shown.

It should be noted that it is obvious that various types of heads other than those described above using the drawings can be constructed without departing from the gist of the present invention.

[Brief explanation of drawings]

FIG. 1 shows a bubble-driven ink jet according to the present invention.
2 and 3 are top views of an orifice plate resistor composite used in a print head, respectively showing semi-finished and completed orifice plate resistor composites of FIG.
FIG. 4 is a perspective view showing a state cut along section A; FIG. Figure 5 is a cross-sectional view taken along line C-C of the back plate shown in Figure 4, and Figure 6 shows the present invention completed by attaching the back plate shown in Figures 4 and 5 to the orifice plate resistance complex shown in Figure 1. FIG. 7 is a cross-sectional view taken along line B-B of the bubble-driven ink-jet print head of the present invention, as viewed from the orifice side. 13.15: Resistance 17. 19, 21: Conductor 23, 25 Niorifice 27: Orifice plate 31 Varnish spacer 35: Back plate Applicant: Yokotsutsu-Heuret-Punkard Co., Ltd. Agent Patent attorney Tsuguo Hasegawa FI6. 6 F1θ7

Claims (1)

[Scope of Claims] A bubble-driven ink jet printing head having an oriswiss plate provided with an aperture for ejecting ink droplets, wherein the oriswiss plate is a means for generating air bubbles in the ink.
Bubble-driven inkjet and print heads featuring a special feature of the invention.