PRINTING A FIBROUS MATERIAL
20220314641 · 2022-10-06
Inventors
Cpc classification
B41J11/0015
PERFORMING OPERATIONS; TRANSPORTING
B41J11/00216
PERFORMING OPERATIONS; TRANSPORTING
D06B1/16
TEXTILES; PAPER
B41J15/06
PERFORMING OPERATIONS; TRANSPORTING
D06B1/148
TEXTILES; PAPER
B41J11/42
PERFORMING OPERATIONS; TRANSPORTING
B41M5/0011
PERFORMING OPERATIONS; TRANSPORTING
B41J2/2114
PERFORMING OPERATIONS; TRANSPORTING
B41J15/048
PERFORMING OPERATIONS; TRANSPORTING
B41J15/165
PERFORMING OPERATIONS; TRANSPORTING
D06B21/00
TEXTILES; PAPER
B41J11/0095
PERFORMING OPERATIONS; TRANSPORTING
B41M5/0064
PERFORMING OPERATIONS; TRANSPORTING
International classification
B41J3/407
PERFORMING OPERATIONS; TRANSPORTING
B41J11/00
PERFORMING OPERATIONS; TRANSPORTING
B41J11/42
PERFORMING OPERATIONS; TRANSPORTING
B41J15/04
PERFORMING OPERATIONS; TRANSPORTING
B41J15/06
PERFORMING OPERATIONS; TRANSPORTING
B41J15/16
PERFORMING OPERATIONS; TRANSPORTING
Abstract
The present invention refers to a plant (1) for printing a fibrous material (T). The printing plant (1) comprises: a station (14) for supplying a fibrous material configured for supplying the fibrous material along a predetermined operative path, a treating station (10) configured for treating the fibrous material with a treatment composition by applying the composition itself on a first side (T1) of the fibrous material (T) ; and a printing station (6) configured for ink-printing at least part of a second side (T2) of the fibrous material (T) opposite to the first side (T1). Moreover, the present invention refers to a process of printing a fibrous material.
Claims
1.-59. (canceled)
60. A method of digital ink-jet printing a fabric, the method comprising: supplying a fabric to be printed along a predetermined operative path, treating supplied fabric with a treatment composition by depositing the treatment composition to the fabric at a first side of the fabric as a foam and then pressing the foam into the fabric such that the treatment composition is forced into the fabric from the first side, and then digitally ink-jet printing at least part of a second side of the treated fabric, opposite to the first side.
61. The method of claim 60, wherein applying the treatment composition comprises depositing the treatment composition as a foam directly and only on the first side of the fibrous material.
62. (canceled)
63. The method of claim 60, wherein the fabric is supplied on a conveyor belt that receives the fabric from a supplying station and guides the received fabric through a printing station in which the at least part of the second side of the treated fabric is digitally ink-jet printed.
64. The method of claim 63, wherein the treatment composition is deposited as a foam, the method further comprising sensing a quantity of the deposited foam.
65. The method of claim 64, wherein sensing comprises detecting foam quantity present immediately upstream of an initial contact between the first side of the fabric and the conveyor belt.
66. The method of claim 63, wherein the conveyor belt directly receives the treatment composition upstream of receiving the fabric.
67. The method of claim 66, wherein the treatment composition deposited on the conveyor belt exposed surface has an initial thickness of between 0.5 and 3 mm.
68. The method of claim 63, wherein the printing station comprises at least one printing module extending across the conveyor belt and defining a printing width, measured normal to the advancement direction, of at least 80 percent of an overall width of the conveyor belt.
69. The method of claim 63, wherein the conveyor belt moves continuously during simultaneous printing of the printing station.
70. The method of claim 63, wherein treating the supplied fabric is performed at a treating station comprising a treatment composition applicator including at least one of the group consisting of: a coating blade extending transverse to the motion of the conveyor belt and movable with respect to the conveyor belt, a spray dispenser movable with respect to the conveyor belt, an applicator roll with an associated respective blade for adjusting a thickness of treatment composition deposited on a lateral surface of the applicator roll, the applicator roll having a rotation axis extending across the conveyor belt and movable with respect to the conveyor belt, a drum having a rotation axis extending across the conveyor belt and movable with respect to the conveyor belt, the drum defining a hollow interior configured to contain a quantity of treatment composition and having a number of nozzles or slits through which the treatment composition is supplied, and a treatment composition distributor comprising a reservoir configured to receive the treatment composition, the reservoir having at least one supplying nozzle defining an outlet of the reservoir and extending across the conveyor belt, the distributor containing one or more toothed wheels configured to push the treatment composition from the nozzle.
71. The method of claim 63, comprising: controlling movement of the conveyor belt, applying the treatment composition at a treating station as a function of a desired value of an operative parameter representative of a quantity of treatment composition to be applied on the fabric, and the movement of said conveyor belt.
72. The method of claim 71, wherein said operative parameter comprises at least one of the group consisting of: a difference in weight per area of the fabric immediately before the treating station and immediately downstream of the treating station, a difference in weight per area of the fabric immediately upstream of the treating station and immediately upstream of the printing station, a volume flow rate of the treatment composition being applied at the treating station, a mass flow rate of the treatment composition being applied at the treating station, and a thickness of the applied treatment composition.
73. The method of claim 60, wherein the treatment composition is deposited by a foam applicator operating below the fabric supplied along said operative path.
74. The method of claim 60, wherein digitally ink-jet printing comprises printing by a single pass ink-jet printer with printing heads fixed during printing.
75. A method of digital ink-jet printing comprising: supplying a fibrous material to be printed along a predetermined operative path to an exposed surface of a conveyor belt that receives and guides the fibrous material along an advancement direction; treating the fibrous material with a treatment composition by depositing the treatment composition to the fibrous material fabric at a first side of the fibrous material as a foam; sensing an accumulation of the treatment composition caused by an initial contact between the treated fibrous material and the conveyor belt; and digitally ink-jet printing, at a printing station, at least part of a second side of the treated fibrous material opposite to the first side, with the fibrous material disposed on the conveyor belt.
76. The method of claim 75, wherein the treatment composition is deposited other than directly to the second side of the fibrous material.
77. The method of claim 75, wherein treating the fibrous material with a treatment composition comprises depositing the treatment composition to the fibrous material at the first side of the fibrous material as a foam and then pressing the foam into the fibrous material such that the treatment composition is forced into the fibrous material from the first side.
78. The method of claim 75, further comprising detecting a foam quantity present immediately upstream of the initial contact between the fibrous material and the conveyor belt.
79. A method of digital ink-jet printing, the method comprising: supplying a fabric to be printed along a predetermined operative path; treating the supplied fabric with a treatment composition by depositing the treatment composition to the fabric at a first side of the fabric as a foam, wherein the foam is deposited other than directly to a second side of the fibrous material opposite the first side; and digitally ink-jet printing at least part of the second side of the treated fabric.
80. The method of claim 79, wherein treating the supplied fabric with the treatment composition comprises depositing the treatment composition to the fabric at the first side of the fabric as a foam and then pressing the foam into the fabric such that the treatment composition is forced into the fabric from the first side.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0162] Some embodiments and some aspects of the invention will be described in the following with reference to the attached drawings, given only in an indicative and therefore non-limiting way, wherein:
[0163]
[0164]
[0165]
[0166]
[0167] Figures from 3 to 7 are lateral schematic view of an applicator of the treating station of the printing plant according to the present invention;
[0168]
[0169]
DEFINITIONS AND MATERIALS
[0170] The figures could illustrate the object of the invention by not-to-scale representations; therefore, parts and components illustrated in the figures regarding the object of the invention, could only indicate schematic representations.
[0171] In the following description and in the attached claims, the terms listed in the following take the meanings specified in the following. [0172] Ink: a mixture formed by a dispersion of pigments or by a solution of dyes in an aqueous or organic medium destined to be transferred on surfaces of different materials for obtaining one or more prints, for example by digital printing; transparent inks and paints are also comprised. For example, the term ink can be understood as an ink comprising at least one of: a water-based acid ink, a reactive ink, a dispersed ink, a pigment ink, a solvent-based dispersed ink, and a dispersed reactive ink.
[0173] The ink for this type of printing can exhibit a viscosity comprised in the range from 1 to 10 mPa.Math.s, preferably from 4 to 8 mPa.Math.s, more preferably about 6 mPa.Math.s measured according to the ASTM D7867-13 method.
[0174] Moreover, the ink can exhibit a surface tension comprised in the range from 25 to 45 mN/m, preferably from 30 to 40 mN/m, more preferably about 35 mN/m, measured according to the ASTM D1331-14 method. The viscosity and surface tension were measured at a temperature of 20° C. and at the atmospheric pressure. Further, the operative temperature is comprised in the range between 15° C. and 45° C., preferably between 30° C. and 40° C.; the operative temperature is understood as the temperature of the ink inside a printing head.
[0175] A person skilled in the art is capable of selecting the type of ink and also the application conditions and the additives suitable for this type of printing and as a function of the type of fibrous material to be printed. [0176] Fibrous material: a material made of fibers of different type—for example fabric, non-woven fabric, knitted fabric, paper or combinations of one or more of the cited supports. Specifically, the fiber of said fibrous material can be derived from a natural, vegetal or animal, artificial or synthetic source, for example can be a fiber of cotton, flax, manila hemp, jute, wool, viscose or artificial silk, acrylic, polyamide (nylon), polyester, polypropylene, polyethylene, chlorovinyl, polyurethane (Elastam), Teflon (Gore-tex), aramid fibers (Kevlar) or mixtures thereof.
[0177] Sheet fibrous material: a fibrous material as hereinbefore defined formed by a structure having two dimensions (length and width) having dimensions substantially prevailing with respect to a third dimension (thickness). The term sheet fibrous material means both a fibrous material consisting of discrete sheets having a limited length (for example the formats A0, A1, A2, A3, A4, etc.) and continuous webs exhibiting a significant length, which can be supplied by a roll on which the sheet material is wound, or can come from an in-line printing step. In any case, the sheet fibrous material, herein described, exhibits two sides or main surfaces, on at least one of which it is provided a print. [0178] Digital printing: printing using one or more nozzle printing heads for applying inks defining motives, patterns, colorations, etc., on sheet materials. The printing heads can be movable transversally to the sheet material advancement direction in order to cover the overall width to be printed, or can be transversally stationary, when the heads width is equal to the printing width, in other words the fabric. [0179] Treatment composition: a composition in the form of a treatment liquid or a treatment foam. The treatment composition comprises one or more liquid compounds, or one or more solid compounds dissolved or dispersed in a suitable liquid phase, having the function of preparing and/or treating at least the surface or surfaces of the sheet fibrous material destined to receive one or more prints. The compound/s can be derived from a natural and/or synthetic (polymers and/or copolymers) sources and can act as one or more of the following: anti-migration agent, thickener, surface tension modifier, acidity modifier, hydrophilicity modifier, hydrophobicity modifier, drying accelerator, fixation improver. The liquid phase can be aqueous, organic, polymeric or mixed. [0180] Treatment liquid: comprises: [0181] at least one anti-migration agent configured for limiting the diffusion of the ink in the fiber of the sheet fibrous material. Such anti-migration agent can for example comprise water-soluble polymers, in other words polymers having a solubility greater than 1%, preferably equal to or greater than 10% of the mass in an aqueous or alkaline solution at 25° C. Particularly, the anti-migration agent can comprise: (sodium, potassium or calcium, preferably sodium) alginates, derivatives of the cellulose, (carboxymethylcellulose, hydroxyethylcellulose), acrylic (co)polymers, xanthan gum, Arabic gum, guar gam and similar; or: [0182] at least one pH control agent (buffering agents). Specifically, the buffering agent can comprise NaHCO.sub.3 (adapted in case of materials of cotton printed with reactive colorant ink for maintaining the alkalinity, for example), a weak acid (for example tartaric acid ammonium for controlling the pH, advantageously but in a non-limiting way used in case of silk and similar materials printed with acid colorant ink), and inert organic acid (for example, citric acid, for controlling the pH in case of polyester-based materials and similar printed with a dispersed colorant ink); and [0183] at least one hydrotropic agent configured for increasing the moisture contents of the fiber or for increasing the solubility of the colorant. Hydrotropic agents are known to the person skilled in the art and are: urea, thiourea and similar.
[0184] Optionally, the treatment liquid can comprise one or more of the following agents: [0185] a surfactant agent configured for increasing the colorant permeability in the fiber. Some surfactants have also the function of anti-migration agents. Such surfactants can comprise non-ionic, anionic surfactants and similar; [0186] an anti-diffusion agent configured for stopping the ink on the sheet fibrous material and/or increasing the color development properties. The anti-diffusion agent can for example comprise silica, alumina, cationic agents and similar. The silica can be used in a silica sol form, in other words as a dispersion. [0187] Other conditioners, such as for example neutral salts, anti-reducing agents, humectants, anti-fermentation agents, and similar.
[0188] The neutral salts have the function of accelerating the depletion of the colorant and are mainly applied to the cotton fibers. Such suitable neutral salts are known to the person skilled in the art and include, for example, sodium chloride, sodium sulfate, and similar.
[0189] The anti-reducing agent is a substance which prevents the reduction of the colorant and therefore prevents a decrease of the colorant concentration. Suitable anti-reducing agents are known to the person skilled in the art and include, for example, meta-nitro benzene sulfonic acid and similar.
[0190] The humectants have the function of moisturizing the fibrous material so that it can be adapted to the ink jet head, and further have the function of controlling the viscosity. Suitable humectants comprise, for example: ethylene glycole, propylene glycole, and similar.
[0191] The anti-fermentation agents instead can comprise 2′-dihydroxy-5,5′-dichlorodiphenylmethane.
[0192] The treatment liquid can be prepared by mixing one or more of the components by conventional methods. As an alternative, individual liquid compositions such as for example: a liquid composition containing an anti-migration agent, a liquid composition containing an anti-diffusion agent, a liquid composition containing a pH control agent for an acid colourant ink, a liquid composition containing a pH control agent for a dispersed colourant ink, a liquid composition containing a pH control agent for a reactive colourant ink, a liquid composition containing a hydrotropic agent, a liquid composition containing a surfactant, or a liquid composition containing a neutral salt, and/or an anti-reducing agent and similar can be prepared. As an alternative, each individual composition can be applied alone to such fibrous material. Both the individual liquid compositions and the treatment liquid are filtered by a membrane, for example an acetate or cellulose nitrate membrane. As an alternative, the treatment liquid can be prepared by suitably diluting a concentrated treatment composition, comprising at least one anti-migration agent, a pH control agent, a hydrotropic agent and, optionally, one or more of the other components as hereinbefore defined. The concentrated composition can be in the form of a paste, preferably having a viscosity of about 300-500 cP measured according to the Brookfield method.
[0193] The treatment liquid, according to the invention, generally has a viscosity greater than 2.0 cP, preferably greater than 5 cP, particularly comprised between 10 and 20 cP. Such viscosity is measured by a DV-II+Viscometer instrument (Brookfield Inc.). Generally, the treatment liquid has a surface tension greater than 20 N/cm.sup.2, preferably greater than 25 N/cm.sup.2, greater than 30 N/cm.sup.2; and/or less than 70 N/cm.sup.2, less than 65 N/cm.sup.2, less than 60 N/cm.sup.2. Generally, such treatment liquid has a surface tension comprised in the range from 20 to 70 N/cm.sup.2. Such surface tension is measured by a Surface Tensiomat 21 instrument (Fisher Scientific Inc.).
[0194] The viscosity and surface tension were measured at a temperature of 20° C. and at the atmospheric pressure.
[0195] In a general formulation of the treatment liquid, the same comprises at least one of: [0196] at least one anti-migration agent, preferably selected among: alginates, derivatives of the cellulose, particularly carboximethylcellulose, hydroxyethylcellulose, acrylic (co)polymers, xanthan gum, Arabic gum, and guar gum; [0197] at least one pH control agent, preferably selected among sodium bicarbonate, sodium carbonate, ammonium sulfate, ammonium tartrate, and citric acid, [0198] at least one hydrotropic agent, preferably selected between urea and thiourea.
[0199] Optionally, the treatment liquid comprises: [0200] at least one anti-migration agent, preferably selected among: alginates, derivatives of the cellulose, such as carboximethylcellulose, hydroxyethylcellulose, acrylic (co)polymers, xanthan gum, Arabic gum, and guar gum; and/or [0201] at least one pH control agent, preferably selected among: sodium bicarbonate, sodium carbonate, ammonium sulfate, ammonium tartrate, and citric acid, and at least one hydrotropic agent, preferably selected between urea and thiourea.
[0202] Optionally, the treatment liquid can further comprise at least one surfactant and/or a neutral salt and/or an anti-reducing agent and/or one humectant and/or one anti-fermentation agent.
[0203] In a first embodiment, the treatment liquid can comprise: [0204] sodium alginate, preferably in a percentage comprised between 0.1% and 1% wt. with respect to the total weight of the composition, and an acrylic (co)polymer, more preferably, Thermacol MP, preferably in a percentage comprised between 8% and 12% wt. with respect to the total weight of the composition, and [0205] water in a quantity needed to reach 100%.
[0206] In an embodiment variant of the first embodiment of the treatment liquid, this latter can comprise: [0207] an acrylic (co)polymer, preferably in a percentage comprised between 10% and 20% wt., and optionally guar gam, preferably in a percentage comprised between 0.1% and 1% wt. with respect to the total weight of the composition, [0208] water in a quantity needed to reach 100%.
[0209] In an embodiment variant of the first embodiment, the treatment liquid can comprise: [0210] an anti-migration agent, for example hydroxyethylcellulose, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0211] a surfactant, for example FLUORAD FC170, preferably in a percentage comprised between 0.1% and 0.5% wt. with respect to the total weight of the composition, [0212] a humectant, for example glycerine, preferably in a percentage comprised between 1% and 4% wt. with respect to the total weight of the composition, and [0213] water in a quantity needed to reach 100%.
[0214] The above described treatment liquid does not comprise both pH control agents and hydrotropic agents. The treatment liquid, defined in the second embodiment, is suitable for interacting with a dispersed ink which does not require both to use pH control agents and hydrotropic agents; further such treatment liquid enables to apply the anti-migration agent separately from the pH control agent and from the hydrotropic agent when reactive or acid ink is used.
[0215] In a second embodiment, the treatment liquid can comprise: [0216] sodium bicarbonate and/or sodium carbonate, in a percentage comprised between 2.5% and 3% wt. with respect to the total weight of the composition, [0217] urea, preferably in a percentage comprised between 6% and 18% wt. with respect to the total weight of the composition, and [0218] water in a quantity needed to reach 100%. In an embodiment variant of the second embodiment of the treatment liquid, this latter can comprise: [0219] ammonium sulfate (solution 1:2) or ammonium tartrate, preferably in a percentage comprised between 4% and 8% wt. with respect to the total weight of the composition, [0220] urea, preferably in a percentage comprised between 6% and 15% wt. with respect to the total weight of the composition, and [0221] water in a quantity needed to reach 100%.
[0222] The treatment liquid defined in the second embodiment does not comprise anti-migration agents and is adapted to interact with pigment inks, which do not require to use anti-migration agents.
[0223] Moreover, as an individual composition, the above defined treatment liquid enables to apply the pH control and hydrotropic agents separately from the anti-migration agent when a reactive or acid ink is used.
[0224] In a third embodiment, the treatment liquid can comprise: [0225] at least one anti-migration agent, preferably selected between alginates, acrylic (co)polymers and guar gam, [0226] at least one pH control agent, preferably selected among sodium bicarbonate, sodium carbonate, ammonium sulfate and ammonium tartrate, [0227] at least one hydrotropic agent preferably urea.
[0228] Preferably, according to the third embodiment, the treatment liquid, for example adapted to interact with reactive inks, can comprise: [0229] alginate, preferably in a percentage comprised between 0.1% and 1% wt. with respect to the total weight of the composition, and an acrylic (co)polymer, preferably Thermacol MP, preferably in a percentage comprised between 8% and 12% wt. with respect to the total weight of the composition, [0230] sodium bicarbonate and/or sodium carbonate, preferably in a percentage comprised between 2.5% and 3% wt. with respect to the total weight of the composition, [0231] urea, preferably in a percentage comprised between 6% and 18% wt. with respect to the total weight of the composition, [0232] an anti-reducing agent, preferably sodium salt of the 3-nitro benzene sulfonic acid (Lyoprint RG) preferably in a percentage comprised between 0.5% and 1% wt. with respect to the total weight of the composition, and [0233] water in a quantity needed to reach 100%.
[0234] Preferably, according to the third embodiment, the treatment liquid, for example adapted to interact with an acid ink, can comprise: [0235] an acrylic (co)polymer, preferably Thermacol MP, preferably in a percentage comprised between 10% and 20% wt., and optionally guar gam, preferably in a percentage comprised between 0.1% and 1% wt. with respect to the total weight of the composition, [0236] ammonium sulfate or ammonium tartrate, preferably in a percentage comprised between 4% and 8% wt. with respect to the total weight of the composition, [0237] urea, preferably in a percentage comprised between 6% and 15% wt. with respect to the total weight of the composition, and optionally [0238] an anti-fermentation agent, preferably 2,2′-dihydroxy-5,5′-dichlorodiphenylmethane (Prevental), preferably in a percentage comprised between 0.01% and 0.15% wt. with respect to the total weight of the composition, and [0239] water in a quantity needed to reach 100%.
[0240] Another example of a treatment liquid according to the third embodiment comprises: [0241] at least one anti-migration agent, preferably selected between carboxymethylcellulose and hydroxyethylcellulose, [0242] at least one pH control agent, preferably selected among sodium carbonate, ammonium tartrate, and citric acid, [0243] at least one hydrotropic agent, preferably urea, [0244] at least one surfactant, preferably a non ionic surfactant, more preferably Triton X100 and at least one humectant, preferably glycerine.
[0245] Another example of the treatment liquid according to the third embodiment comprises: [0246] carboxymethylcellulose, preferably in a percentage comprised between 1% and 3% wt. with respect to the total weight of the composition, [0247] sodium bicarbonate, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0248] urea, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0249] Triton X100, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, and glycerine, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, and [0250] water in a quantity needed to reach 100%.
[0251] The above defined treatment liquid is advantageously adapted to interact with reactive inks.
[0252] Another example of a treatment liquid according to the third embodiment comprises: [0253] hydroxyethylcellulose, preferably in a percentage comprised between 1.5% and 4% wt. with respect to the total weight of the composition, [0254] ammonium tartrate, preferably in a percentage comprised between 1.5% and 4% wt. with respect to the total weight of the composition, [0255] urea, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0256] Triton X100, preferably in a percentage comprised between 0.1% and 1% wt. with respect to the total weight of the composition, and glycerine, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, and water in a quantity needed to reach 100%.
[0257] The above defined treatment liquid is advantageously adapted to interact with an acid colourant ink.
[0258] Another example of the treatment liquid according to the third embodiment comprises: [0259] carboxymethylcellulose, preferably in a percentage comprised between 0.5% and 3% wt. with respect to the total weight of the composition, [0260] citric acid, preferably in a percentage comprised between 0.05% and 1% wt. with respect to the total weight of the composition, [0261] urea, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0262] Triton X100, preferably in a percentage comprised between 0.1% and 1% wt. with respect to the total weight of the composition, and glycerine, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, and [0263] water in a quantity needed to reach 100%.
[0264] The above defined treatment liquid is advantageously, but in a non-limiting way, adapted to interact with a dispersed ink.
[0265] Examples of individual compositions useable in the present invention, are listed in the following:
[0266] In a first embodiment variant, an individual composition can comprise: [0267] a hydrotropic agent, for example urea, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0268] a surfactant, FLUORAD FC170 for example, preferably in a percentage comprised between 0.1% and 0.5% wt. with respect to the total weight of the composition, [0269] a humectant, for example glycerine, preferably in a percentage comprised between 1% and 4% wt. with respect to the total weight of the composition, and [0270] water in a quantity needed to reach 100%.
[0271] In a further embodiment variant, an individual composition can comprise: [0272] sodium bicarbonate, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0273] a surfactant, FLUORAD FC170 for example, preferably in a percentage comprised between 0.1% and 0.5% wt. with respect to the total weight of the composition, [0274] a humectant, for example glycerine, preferably in a percentage comprised between 1% and 4% wt. with respect to the total weight of the composition, and [0275] water in a quantity needed to reach 100%.
[0276] This latter defined individual liquid composition is advantageously, but in a non-limiting way, adapted to interact with reactive colourant inks.
[0277] In a further embodiment variant, an individual composition can comprise: [0278] ammonium tartrate or ammonium sulfate, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0279] a surfactant, FLUORAD FC170 for example, preferably in a percentage comprised between 0.1% and 0.5% wt. with respect to the total weight of the composition, [0280] a humectant, for example glycerine, preferably in a percentage comprised between 1% and 4% wt. with respect to the total weight of the composition, and [0281] water in a quantity needed to reach 100%.
[0282] The above defined individual liquid composition is advantageously, but in a non-limiting way, adapted to interact with acid colourant inks.
[0283] In a further embodiment variant, an individual composition can comprise: [0284] citric acid, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0285] a surfactant, FLUORAD FC170 for example, preferably in a percentage comprised between 0.1% and 0.5% wt. with respect to the total weight of the composition, [0286] a humectant, for example glycerine, preferably in a percentage comprised between 1% and 4% wt. with respect to the total weight of the composition, and [0287] water in a quantity needed to reach 100%.
[0288] The above defined individual liquid composition is advantageously, but in a non-limiting way, adapted to interact with dispersed colourant inks.
[0289] In a further embodiment variant, an individual composition can comprise: [0290] a surfactant, Triton X-705 for example, preferably in a percentage comprised between 3% and 7% wt. with respect to the total weight of the composition, [0291] a surfactant, FLUORAD FC170 for example, preferably in a percentage comprised between 0.1% and 0.5% wt. with respect to the total weight of the composition, [0292] a humectant, glycerine for example, preferably in a percentage comprised between 1% and 4% wt. with respect to the total weight of the composition, and [0293] water in a quantity needed to reach 100%. [0294] Treatment foam: comprises a dispersion of a gas in a liquid medium; further the foam can exhibit the characteristics of colloidal dispersions. The foam can be obtained by directly blowing a high-pressure gas into the liquid medium or by exploiting foaming agents.
[0295] In an embodiment, the treatment foam comprises the treatment liquid, as hereinbefore described and, optionally, one or more additives such as for example: foaming agents, wetting agents and viscosity modifying agents.
[0296] Suitable foaming agents are known to the person skilled in the art, and comprise, for example, surfactants, for example cationic, anionic, amphoteric, non-ionic surfactants; for example, alkyl betaines, particularly laurylamidopropylbetaine, can be used. Adapted wetting agents comprise, for example, silicone derivatives. Viscosity modifying agents comprise, for example, modified or substituted cellulose and poly(meth)acrylic acids and salts thereof, such as for example, ammonium salts, preferably: hydroxyethylcellulose, carboxymethylcellulose and cellulose dimethylpropane sulfonate.
[0297] The composition defining the treatment foam can, for example, comprise: [0298] a treatment liquid in a percentage comprised between 5% and 75%, preferably between 10% and 60% wt. with respect to the total weight of said composition, [0299] at least one foaming agent in a percentage comprised between 0.2% and 5%, preferably between 0.4% and 2% wt. with respect to the total weight of said composition, [0300] water in a quantity needed to reach 100%.
[0301] The wetting agent, if present in the composition of the treatment liquid used for producing the foam, has a percentage comprised between 0.001% and 5%, preferably from 0.01% to 1% wt. with respect to the total weight of said composition. The viscosity modifying agent, if present in the composition of the treatment liquid used for producing the foam, has a percentage comprised between 0.001 and 5%, preferably from 0.01% to 1% wt. with respect to the total weight of said composition.
[0302] The medium which can be used for producing the foam of the invention is well known to the person skilled in the art, and many different mediums are commercially available. For example, in case a gas, for example air, is directly blown at high pressure into the liquid medium and/or in case foaming agents are used, a mechanical stirrer, a conventional mixer, or a foam generator can be used.
[0303] The density of the treatment foam is greater than 0.005 g/cm.sup.3, preferably is comprised between 0.01 g/cm.sup.3 and 0.3 g/cm.sup.3; the foam density was obtained by introducing a determined foam volume in a graduated laboratory cylinder of a known weight, by determining the weight of the foam and calculating the density from the known volume and weight. The expansion ratio of the treatment foam, defined as the ratio between the weight of the liquid and a weight of the same volume of foam prepared by this liquid, is comprised between 2:1 and 6:1, preferably between 3:1 and 5:1.
[0304] The average diameter of the cells of the foam, according to the invention, is greater than 0.05 mm, preferably comprised between 0.08 and 0.5 mm. The average diameter of the cells of the foam was measured by placing a foam sample on a microscope slide, by observing with a microscope having an enlargement of 32 times, and by counting the number of cells in an area of 6.77 mm.sup.2. Particularly, the average diameter D of the cells, measured in mm, was determined by the equation:
D=2/√π.Math.[(6.77)(liquid density−foam density)/cells number].sup.1/2
[0305] Preferably, the treatment foam can comprise: [0306] a treatment liquid in a percentage comprised between 5 and 75% wt. with respect to the total weight of the foam, such treatment liquid can comprise: [0307] at least one anti-migration agent, preferably selected among alginates, derivatives of the cellulose, such as carboximethylcellulose, hydroxyethylcellulose, acrylic (co)polymers, xanthan gum, Arabic gum, and guar gum, and/or [0308] at least one pH control agent, preferably selected among: sodium bicarbonate, sodium carbonate, ammonium sulfate, ammonium tartrate, and citric acid, and at least one hydrotropic agent, preferably selected between urea and thiourea, [0309] at least one foaming agent in a percentage comprised between 0.2% and 5%, preferably between 0.4 and 2% wt. with respect to the total weight of the foam, [0310] water in a quantity needed to reach 100%. [0311] Hydrophobicity: the term water-repellency or hydrophobicity means the physical properties of chemical species (for example molecules) of being repelled by water. Moreover, this term is used with a more general meaning for denoting the property of materials of not absorbing and not retaining water inside them or on their surface.
[0312] The variation of hydrophobicity of the fibrous material before and after the plasma-treatment is measured by the contact angle, in other words the magnitude of the angle, measured in Angstrom degrees, present between the surface of the fibrous material and the tangent to the liquid-vapour interface of a water drop. The hydrophobicity variation of the fibrous material before and after the plasma treatment according to the invention, can be measured when the surface of a sample of the fibrous material contacts a distilled water drop 1 cm high for 60 seconds, by measuring the quantity in grams of distilled water absorbed by the material, and weighing the sample of the material before and after the test. The results are expressed in grams/m.sup.2 of absorbed water.
[0313] Standard atmosphere: an atmosphere at a temperature of 288.15 K (15° C.), at a pressure of 101.325 kPa (1 tm) and at a humidity of 0.00.
DETAILED DESCRIPTION
[0314] Printing Plant
[0315] 1 generally indicates a plant for printing, particularly for digitally printing, a sheet fibrous material T, for example as a discrete sheet or as continuous web. The plant 1, object of the invention, is useable for ink-printing at least one side of said sheet fibrous material T which, for example, can be formed by or can comprise a fabric and/or non-woven fabric. Generally, but in a non limiting way, the plant 1 can be applied in the textile or knitted fabric or non-woven fabric industry for printing by ink.
[0316] As it is visible in the attached figures, the plant 1 comprises at least one conveyor belt 2 movable along a closed path, particularly between at least one first and one second end idler members 2a, 2b. The conveyor belt 2 exhibits a structure having two dimensions: length and width (the width is identified by the letter L as illustrated in
[0317] The conveyor belt 2 exhibits two main surfaces or sides: an exposed surface S and an inner surface I. The inner surface I is configured for directly contacting the idler members 2a, 2b adapted to guide the operative section of the belt 2 along the cited movement direction, while the exposed surface S is configured for receiving the fibrous material T; particularly, the exposed surface S is configured for facing and receiving a first side T1 of the sheet fibrous material T. In a preferred, but non limiting configuration of the invention, the conveyor belt 2—at least at a continuous longitudinal band of the exposed surface S destined to receive the sheet fibrous material T—is devoid of through openings crossing the thickness of the belt 2 itself; particularly, at least the exposed surface S destined to receive the sheet fibrous material T is completely smooth, devoid of holes (through openings, for example) and advantageously devoid of valleys and projections. Advantageously, but in a non-limiting way, the conveyor belt 2 comprises at least one continuous layer of water-proof material defining the exposed surface and capable of providing the surface itself, according to a view normal to the movement direction, with a continuous and preferably rectilinear outline. For example, the conveyor belt 2 can be made at least partially of at least one material selected in the group of the following: elastomeric materials, silicone, silicone rubber or other.
[0318] The exposed surface S of the conveyor belt 2 exhibits constantly an operative section 3 configured for temporarily contactingly receiving the first side T1 of the fibrous material T. De facto, at least part of the closed path of the conveyor belt 2 defines the operative section 3 for transporting the fibrous material T; the operative section 3 is defined by the portion of the belt 2 which moves the fibrous material T, in other words from the portion of the belt 2 directly supporting the fibrous material T. The operative section 3 is defined by a portion of the path between the first and second idler members as illustrated in
[0319] In a preferred but non-limiting arrangement of the invention, the conveyor belt 2 comprises only the first and second idler members and therefore exhibits a substantially rectangular closed path, radiused at said members; under such condition, the operative section 3 is defined by a rectilinear portion of the rectangular path: the material T therefore would be transported by the belt 2 along a rectilinear section, particularly a flat one. De facto, the conveyor belt 2 is configured for temporarily receiving and supporting the fibrous material T; during the movement of the conveyor belt 2, this latter is configured for guiding the fibrous material T moving along an advancement direction A (see
[0320] As it is visible in the attached figures, the exposed surface of the conveyor belt 2 comprises constantly a depositing section 3a extending upstream the operative section 3 of the conveyor belt 2 itself with respect to the advancement direction A. As it will be better described in the following, the depositing section 3a of the exposed surface S is configured for receiving a treatment composition M adapted to contact the fibrous material T in the operative section 3.
[0321] The depositing section 3a extends on the same rectilinear section of the rectangular closed path of the conveyor belt 2 on which said operative section 3 is defined. More particularly, the depositing section 3a extends substantially from the first idler member 2a towards the second member 2b. Still more particularly, the depositing section 3a extends from the first idler member 2a to the operative section 3: the depositing section 3a and operative section 3 are immediately consecutive to each other along the advancement direction A of the fibrous material T.
[0322] From the dimensional point of view, the conveyor belt 2 is configured for exhibiting a width L equal to or greater than a maximum width of the fibrous material T (see
[0323] The conveyor belt 2—during a predetermined operative condition is configured for moving continuously the fibrous material T at a speed constantly greater than 0 along the advancement direction A. During the operative condition of the conveyor belt 2, the same is always and constantly moving. Still in other words, during the operative condition of the conveyor belt 2, the same does not provide to alternately move step-by-step, wherein dwells of the belt along the moving direction are provided.
[0324] In a preferred but non-limiting arrangement of the invention, the plant 1 comprises at least one control unit 9 (outlined in
[0327] As hereinbefore discussed, the depositing section 3a is configured for receiving a treatment composition. The conveyor belt 2—due to the motion thereof—is configured for transporting the treatment composition applied on the depositing section 3a to an initial contact area wherein the conveyor belt 2 is estimated to start to come in contact with the fibrous material T supplied along said operative path. Particularly, the initial contact area is a connecting area between the depositing section 3a and operative section 3: the depositing section, initial contact area and operative section are immediately consecutive to each other and extend, without interruption, along the closed operative path of the belt 2, particularly along the advancement direction A of the fibrous material T.
[0328] Advantageously but in a non-limiting way, the plant 1 comprises at least one pressure organ 5a (see
[0329] Moreover, the plant 1 can comprise an anvil pressure organ 5b (see
[0330] The initial contact area of the belt is—with the fibrous material—interposed between the pressure organs 5a and 5b.
[0331] Advantageously, at least the pressure organ 5a (optionally both the pressure organ 5a and anvil organ 5b) extend transversally to the conveyor belt 2 (particularly normal)—with respect to said movement direction and particularly with respect to the advancement direction A of the fibrous material T—for defining a length substantially identical to the width of the sheet fibrous material. More particularly, each pressure organ exhibits a length substantially equal to the width L of the belt 2.
[0332] Advantageously, at least the pressure organ 5a comprises a completely smooth (devoid of cavities and/or through openings) outer circular contact surface of waterproof material.
[0333] As it is visible in
[0334] The treating station 4 comprises at least one applicator 12 of the treatment composition, operating below the fibrous material T supplied along the operative path. Particularly, the applicator 12 is disposed upstream the pressure organ 5a with respect to the movement direction, particularly with respect to the advancement direction A of the fibrous material T.
[0335] More specifically, the applicator 12 is positioned and configured for disposing the treatment composition M on the exposed surface S of the depositing section 3a of the conveyor belt 2. De facto, the applicator 12 deposits the treatment composition on the portion of the conveyor belt 2 which does not still contact the fibrous material T.
[0336] After moving the belt, the treatment composition M applied on the exposed surface is guided to the initial contact area wherein the composition is brought in direct contact with the first side T1 of the fibrous material. The contact of the belt with the fibrous material causes the composition to treat the fibrous material T from the first side T1: the composition passes through at least part of the thickness of the fibrous material for enabling the treatment.
[0337] As hereinbefore described, in an embodiment of the invention, the conveyor belt 2 defines an operative condition wherein the same continuously moves the fibrous material T constantly at a speed greater than 0; the treating station 4 is configured for disposing, during the predetermined operative condition, on the depositing section 3a, the treatment composition M. More particularly, the conveyor belt 2, during the operative condition, is configured for continuously moving the fibrous material T through the treating station 4 which deposits continuously the treatment composition M on the section 3a.
[0338] The treatment composition M supplied by the treating station 4, independently from the liquid or foam state of the treatment composition, can comprise for example one of the following agents: an anti-migration agent, a pH control agent, a hydrotropic agent.
[0339] The treating station 4 is configured for disposing, on the sliding section 3a, a predetermined quantity of the treatment composition M; said quantity of the treatment composition M is selected so that the treated fibrous material T (the fibrous material which has received the treatment composition) exhibits a weight percentage per square meter variation, between a cross-section immediately upstream the pressure organ 5a (the fibrous material which is not still in contact with the treatment composition) and a cross-section immediately downstream the pressure organ 5a, less than 70%, particularly comprised between 10% and 50%, still more particularly comprised between 10% and 30%.
[0340] As hereinbefore described, in a configuration of the plant 1, the same comprises the control unit 9. In a preferred but non-limiting embodiment of the invention, the treatment composition M comprises, and particularly is, a treatment foam, and the plant 1 comprises: [0341] at least one foam sensor 11 configured for emitting a control signal representative of the foam quantity placed immediately upstream the initial contact area, [0342] the control unit 9 connected to the foam sensor 11 (see the connecting lines a, b, c in
[0343] More particularly, the foam sensor 11 is configured for generating said control signal which exhibits at least one characteristic related to a size of the foam accumulation in a predetermined control plane, said control unit being configured for: [0344] receiving said control signal, [0345] determining, based on said control signal, a measured value of the size of said foam accumulation, [0346] comparing said measured value with at least one reference value or range, [0347] controlling said applicator 12 based on a difference between said measured value and said reference value or range.
[0348] Still more particularly, the control unit 9 is configured for: [0349] commanding said applicator to increase a deposition flow rate of said foam on the belt if the measured value of the size of said foam accumulation is less than the reference value or range, and [0350] commanding said applicator to reduce the deposition flow rate of the foam on the belt 2 if the measured value of the size of said foam accumulation is greater than the reference value or range,
[0351] The sensor 11, as illustrated in
[0354] The primary signal can comprise an electric, electromagnetic or acoustic signal. The secondary signal can comprise an electric, electromagnetic or acoustic signal.
[0355] As an alternative, the foam sensor 11 can comprise: [0356] a first presence sensor 11c (
[0358] Moreover, the plant 1 can comprise at least one movement sensor connected to the conveyor belt 2 and configured for emitting a monitoring signal representative of a movement speed of the conveyor belt along the advancement direction A. The control unit is connected to the movement sensor and is configured for receiving said monitoring signal and controlling said applicator based on said monitoring signal.
[0359] Particularly, the control unit is configured for: [0360] receiving, for example from the movement sensor engaged with the conveyor belt 2, a signal regarding the movement of the conveyor belt 2, [0361] determining, as a function of the monitoring signal, a measured value of the movement speed of the conveyor belt 2 along the advancement direction A, particularly the movement speed of the fibrous material T along the advancement direction A, [0362] controlling the applicator based on the measured value of the movement speed of the conveyor belt, particularly as a function of the movement speed of the fibrous material T. Particularly, controlling the quantity (flow rate) of the treatment composition supplied by the applicator.
[0363] Particularly, the control unit is configured for: [0364] commanding the applicator 12 to increase a deposition flow rate of the treatment composition if the measured value of the movement speed of the conveyor belt 2 is less than the reference value or range, and [0365] commanding the applicator 12 to reduce the deposition flow rate of the treatment composition if the measured value of the movement speed of the conveyor belt 2 is greater than the reference value or range.
[0366] The quantity of the treatment composition, managed by the control unit 9 by means of the applicator 12, is selected so that the fibrous material T itself exhibits a weight percentage per square meter variation, between a cross-section immediately upstream the pressure organ 5a (the material has not still received the composition) and a cross-section immediately downstream the pressure organ 5a, less than 70%, particularly comprised between 10% and 50%, still more particularly between 10% and 30%.
[0367] More particularly, in a first example, the applicator 12 of the treating station 4 comprises at least one nozzle dispenser 18 (
[0368] The applicator 12 is configured for applying on the exposed surface S of the conveyor belt, a treatment foam exhibiting, immediately downstream the applicator 12, a thickness less than 5 mm, particularly comprised between 0.5 and 3 mm.
[0369]
[0370] In a further alternative, the applicator is reciprocally movable transversally to a motion direction of the conveyor belt and is configured for covering a predetermined transversal width of this latter.
[0371] In a second example, the applicator 12 of the treating station 4 comprises a coating blade 19 (FIGS. 2A and 4) placed transversally to the motion of the conveyor belt 2, and distanced above the depositing section 3a. The coating blade 19 can be associated to a distributor 20 of the treatment composition M, configured for disposing on the depositing section 3a, a predetermined quantity of the treatment composition M. The blade 19 is disposed immediately downstream the distributor 20 along the movement direction and is configured for coating on the exposed surface, the treatment composition M supplied by the distributor 20. Advantageously, the coating blade is used, in a non-limiting way, for coating a material M comprising or consisting only of a treatment foam. Advantageously, as illustrated in
[0372]
[0377] Moreover, the control unit 9 can be connected to an actuator (not illustrated in the attached figures), connected to the blade and configured for moving this latter along the adjustment direction R: the control unit can be configured for commanding the actuator to manage a minimum distance between the blade and the conveyor belt 2.
[0378] Moreover, the plant 1 can comprise at least one further sensor, for example a further foam sensor, substantially identical to the above described foam sensor 11. However, the further foam sensor is configured for emitting a control signal representative of the foam quantity placed immediately at an area wherein the treatment composition is supplied by the applicator, particularly immediately upstream the blade of the applicator 12. The control unit is connected to the further foam sensor and is configured for receiving the control signal of the further foam sensor and for determining the quantity of foam placed immediately upstream the blade and particularly at a supplying area of the applicator. The control unit, after detecting the quantity of foam, is configured for controlling the applicator and particularly the distributor 20.
[0379] More particularly, the further foam sensor is configured for generating the control signal which exhibits at least one characteristic related to a size of an accumulation of foam in a predetermined control plane immediately upstream the applicator blade; the control unit being configured for: [0380] receiving said control signal, [0381] determining, based on said control signal, a measured value of the size of said foam accumulation immediately upstream the blade of the applicator, [0382] comparing said measured value with at least one reference value or range, [0383] controlling the supplying of the foam from the applicator based on a difference between said measured value and said reference value or range of said accumulation.
[0384] Based on the detected value, the control unit is configured for: [0385] commanding the applicator to increase a deposition flow rate of said foam on the belt if the measured value of the size of said foam accumulation immediately upstream the blade of the applicator, is less than the reference value or range, and [0386] commanding said applicator to reduce the deposition flow rate of the foam on the belt if the measured value of the size of said foam accumulation immediately upstream the blade of the applicator, is greater than the reference value or range.
[0387] In a third example, the applicator 12 of the treating station 4 comprises a drum 23 (
[0392] In a fourth example, the applicator 12 of the treating station 4 comprises an applicator roll (this condition is not illustrated in the attached figures) with an associated respective blade for adjusting a thickness of the treatment composition M deposited on a lateral surface of the applicator roll. The applicator roll and blade extend transversally to the conveyor belt 2 and extend substantially along all the width of said belt. The applicator roll is positioned with the rotation axis transversal to the motion of the conveyor belt 2 and with the lateral surface distanced above the section 3a of the conveyor belt 2.
[0393] In a fifth example, the applicator 12 of the treating station 4 comprises a distributor 25 comprising a reservoir 26 configured for receiving the treatment composition M (
[0394] As hereinbefore described, advantageously the plant 1 can comprise a control unit 9; in such arrangement, the unit 9 can be active on the pusher for managing the quantity of the treatment composition M to be supplied on the conveyor belt 2. More particularly, the control unit 9 is connected to the pusher and is configured for: [0395] receiving, from the movement sensor engaged with the belt 2, the monitoring signal regarding the movement of the conveyor belt 2, [0396] receiving from the sensor 11, the control signal, [0397] managing, as a function of said control and/or monitoring signals, the pusher (when a toothed wheel manages the rotation speed of the wheel) in order to supply a predetermined quantity of the treatment composition M on the depositing section 3a.
[0398] The applicator 12 is configured for applying on the exposed surface of the conveyor belt, a treatment foam exhibiting, immediately downstream the applicator 12, a thickness less than 5 mm, particularly comprised between 0.5 and 3 mm.
[0399] As it is visible in the attached figures, the plant 1 further comprises a printing station 6 configured for ink-printing, particularly by a digital print, at least part of the second side T2 of the fibrous material T opposite to the first side T1. The printing station 6 operates at the conveyor belt 2 and is configured for printing the fibrous material T (particularly the second side T2) placed on the operative section 3 of the conveyor belt 2. The printing station operates on the conveyor belt 2 immediately downstream the treating station 4. In an embodiment variant, between the treating station 4 and printing station 6, there can be a drying station 16 configured for drying the fibrous material moving along the advancement direction A.
[0400] The printing station 6 comprises at least one printing module 7 extending transversally, particularly normal, to the movement direction of the operative section of the conveyor belt 2. In a preferred but non-limiting arrangement of the invention, each printing module 7 exhibits a width, measured normal to the cited movement direction, slightly less (for example 5%-10% less), equal to or greater than the width of the conveyor belt 2. De facto, each printing module 7 is configured for defining a width equal to or greater than the width of the fibrous material T which, during the use, is brought to adhere on the conveyor belt ; such width being measured normal to the advancement direction A of the fibrous material T.
[0401] Each printing module 7, during the predetermined operative condition of the conveyor belt 2 (the conveyor belt moves continuously so that the fibrous material T continuously moves at a speed greater than 0), is configured for: [0402] defining a print on all a width of the fibrous material T, [0403] remaining in a fixed position and printing the second side T2 of the fibrous material T sliding on the operative section 3.
[0404] In other words, providing a printing module 7 extending along all the width of the fibrous material T, enables the module itself to remain still—particularly enables to not perform any type of displacements along a longitudinal and/or transversal directions with respect to the movement direction of the operative section of the conveyor belt 2—during the operative condition of the conveyor belt (continuously moving the belt 2) and continuously performing a printing on the fibrous material T by only the movement imparted to the fibrous material T.
[0405] More particularly, each printing module 7 comprises a plurality of heads 8 (Figures from 9 to 11) configured for covering, by the respective nozzles, all the width of the conveyor belt, particularly of the fibrous material T.
[0406] In a further embodiment illustrated in
[0407] As hereinbefore described, in a preferred but non-limiting embodiment of the plant 1, this latter comprises a control unit 9 active on the conveyor belt 2 and connected to a monitoring sensor engaged with said belt 2; moreover, the control unit 9 is connected to the printing station 6 (see the connecting lines c-d-f in
[0411] Particularly, the control unit 9 is configured for managing the continuous movement of the conveyor belt 2 and, simultaneously, for managing the printing station 6 as a function of the movement speed of the fibrous material T along the advancement direction A.
[0412] Therefore, the plant 1, provided with the conveyor belt 2 and printing station 6, can comprise one or more treating stations 4 positioned upstream the printing station 6.
[0413] In an embodiment of the plant illustrated in
[0414] As it is visible in the attached figure, the plant 1 can comprise a supplying station 14 configured for supplying, particularly directly, the fibrous material to the treating station 4.
[0415] The supplying station 14 can comprise a roll of material T placed on a drum, the rotation thereof being commanded by a motor. The fibrous material T is unwound from the drum and supplied to the treating station 4. In a preferred but non-limiting embodiment of the invention, the plant 1 comprises a control unit 9 active on the supplying station 14 (see the line a in
[0419] In an embodiment variant of the invention, the fibrous material T can be withdrawn from a different supplying station 14 configured for storing as flat layers or bends the fibrous material T (this condition is not illustrated in the attached figures). Moreover, it is not excluded the possibility of directly withdrawing the fibrous material exiting from a further plant for treating the material T such as, for example, a rameuse machine.
[0420] As it is visible in the attached figures, moreover the plant 1 can comprise a vaporizer 15 (typically known in the field as “vapor treating devices” or “steam agers”) placed downstream the printing station 6 and, if present, downstream the further treating station 10. The vaporizer 15 is configured for drying the fibrous material T provided with print in order to perform a fixing treatment of the printing ink on the material T: the printed material is contained in an environment having a vapor at conditions of pressure and temperature suitable for ensuring to fix the ink to the fibers of the material.
[0421] As it is visible in the attached figures, moreover the plant 1 can further comprise at least one drying station 16 positioned downstream the printing station 6 and configured for drying the fibrous material T.
[0422] Advantageously, but in a non-limiting way, the plant can comprise a drying station positioned upstream the printing station 6 and particularly positioned between the pressure organ 5a and printing station 6. The drying station can comprise, for example, one or more irradiation lamps, particularly infrared lamps. Moreover, the drying station 16 can comprise a blowing system configured for generating an air flow at the sheet fibrous material.
[0423] As it is visible in
[0424] The gathering station 17 can comprise a drum rotatively commanded by a motor, on which the printed fibrous material is wound.
[0425] In a preferred but non-limiting embodiment of the invention, the control unit 9 active on the gathering station 17 (see line m in
[0429] In an embodiment variant of the invention, the printed fibrous material T can be accumulated as flat layers or as bends in a different gathering station (this condition is not illustrated in the attached figures).
[0430] Moreover, it is not excluded the possibility of directly supplying the printed fibrous material exiting the printing station 6—as an alternative exiting the vaporizer or drying station if present—to a further plant for treating the material T.
[0431] Printing Process
[0432] Moreover, it is an object of the present invention a process of printing a sheet fibrous material T particularly performed by the plant 1 according to anyone of the attached claims and/or according to the above given description. The process comprises a step of accumulating the fibrous material T, for example from the supplying station 14, and of supplying the same to the treating station 4. Particularly, the process can comprise a step of unwinding the fibrous material T from the drum of the supplying station 14.
[0433] The fibrous material is constrained on the exposed surface of the conveyor belt 2 for defining the operative section 3 wherein the belt supports the fibrous material. The first side T1 is brought in contact with the exposed surface of the belt 2. The fibrous material T therefore is moved—by the conveyor belt 2—along an advancement direction A.
[0434] Advantageously, but in a non-limiting way, the fibrous material T is constrained (for example by applying an adhesive material) to the exposed surface of the belt 2 so that this latter can stably support said moving material T. The exposed surface S exhibits constantly an operative section 3 of the belt 2, configured for temporarily contactingly receiving the first side T1 of the fibrous material T and guiding such fibrous material along an advancement direction A. In a preferred but non-limiting arrangement of the invention, the conveyor belt 2 continuously moves the fibrous material T along an advancement direction A at a speed constantly greater than 0 (the operative condition of the conveyor belt 2). More particularly, the fibrous material T is continuously moved along the advancement direction A at a speed constantly comprised between 20 and 100 m/min, particularly comprised between 30 and 70 m/min.
[0435] The process comprises a step of applying the treatment composition to the first side T1 of the fibrous material T for example by means of one or more applicators 12. Particularly, the step of applying the composition comprises depositing this latter directly on the first side T1 of the sheet fibrous material, since there is no direct deposition of the composition on the second side T2. The step of applying the treatment composition is performed by an applicator 12 acting on the conveyor belt 2 upstream the operative section 3 with respect to the advancement direction of the sheet fibrous material itself.
[0436] More particularly, the step of applying the treatment composition comprises at least depositing a predetermined quantity of the treatment composition on the depositing section 3a of the conveyor belt 2 by one or more applicators.
[0437] More particularly, the process comprises at least the following steps: [0438] generating a predetermined quantity of the treatment composition, [0439] supplying the treatment composition to the applicator 12.
[0440] The step of applying the treatment composition is performed by one or more of the following steps: [0441] applying by a coating blade placed transversally to the motion of the conveyor belt and distanced above the operative section, [0442] applying by a spray dispenser distanced above the operative section, [0443] applying by a roll dispenser having an associated respective blade for adjusting the thickness of the treatment composition deposited on the lateral surface of the roll dispenser, this latter being placed with the rotation axis transversal to the motion of the conveyor belt and with the lateral surface distanced above the operative section of the conveyor belt, [0444] applying by a drum placed with the rotation axis transversal to the motion of the conveyor belt and with the lateral surface distanced above the operative section of the conveyor belt, the drum exhibiting a hollow interior destined to receive a predetermined quantity of the treatment composition and being provided with a predetermined number of nozzles or slits for supplying the composition, [0445] applying by a distributor 25 comprising a reservoir 26 configured for receiving the treatment composition, the reservoir 26 exhibiting at least one supplying nozzle 27 defining an outlet of the reservoir 25, the nozzle 27 extending transversally to the motion of the conveyor belt 2 for all the width of this latter, the distributor 25 comprises one or more pushers, for example one or more toothed wheels, placed inside the reservoir and configured for supplying the treatment composition from the nozzle 27.
[0446] Following the step of applying the treatment composition on the depositing section—the conveyor belt 2 moves the treatment composition to an initial contact area wherein the conveyor belt 2 is estimated to start to come in contact with the fibrous material T. As illustrated in
[0447] The process comprises at least one step of bringing in contact the first side T1 of the fibrous material T with the exposed surface of the conveyor belt 2 so that the same can define an operative section 3 wherein the conveyor belt 2 supports the fibrous material. Constraining the fibrous material to the belt is performed by a step of pressing the material itself against the conveyor belt at the initial contact area, for example by one or more pressure organs or rolls or cylinders.
[0448] Due to the pressure of the fibrous material on the belt, the process enables the treatment composition—directly and only applied on the first side T1 of the material T—to treat the material and particularly to expand inside the material itself. In this way, the step of contacting (pressuring) the material enables an uniform and correct treatment of the sheet fibrous material.
[0449] In a preferred but non-limiting embodiment of the process, the treatment composition comprises a treatment foam. In such arrangement, the process can comprise at least the following steps: [0450] moving the conveyor belt 2, [0451] detecting the quantity of the treatment composition, particularly the treatment foam accumulated at the initial contact area,
[0452] commanding to supply the treatment composition on the depositing section 3a as a function of the accumulated foam quantity at the initial contact area. Particularly, the process comprises the following steps: [0453] emitting, particularly by a sensor, a control signal representative of the foam quantity placed immediately upstream the initial contact area, [0454] determining, for example by means of a control unit 9, based on said control signal, a measured value of the size of said foam accumulation, [0455] comparing, for example by means of the control unit 9, said measured value with at least one reference value or range, [0456] controlling, for example by means of the control unit, the applicator based on a difference between said measured value and said reference value or range.
[0457] More particularly, the control step comprises at least the following sub-steps: [0458] commanding the applicator to increase a depositing flow rate of said foam on the belt if the measured value of the size of said foam accumulation is less than the reference value or range, and [0459] commanding the applicator to reduce the depositing flow rate of the foam on the belt if the measured value of the size of said foam accumulation is greater than the reference value or range.
[0460] De facto, by monitoring the accumulation of foam, the process adjusts the supply of the treatment composition in order to deliver the desired foam quantity to the fibrous material.
[0461] Besides such control, the process can adjust the supply of the treatment composition—comprising both liquid and/or treatment foam—by monitoring and controlling the movement speed of the conveyor belt. De facto, based on the movement speed of the belt and therefore of the fibrous material along the advancement direction A, the process adjusts the quantity of the composition to be supplied on the depositing section 3a.
[0462] More particularly, the process can comprise the following steps: [0463] emitting, particularly by means of a monitoring sensor, a signal regarding the motion of the conveyor belt, [0464] determining, as a function of said monitoring signal, a movement speed of the fibrous material T along the advancement direction A, [0465] as a function of the movement speed of the fibrous material T, commanding to supply the treatment composition, optionally for meeting a desired value of at least one of the following operative parameters: [0466] the composition exhibits, on the depositing section, a thickness less than 5 mm, particularly comprised between 0.5 and 3 mm, [0467] the weight percentage per square meter variation of the sheet fibrous material, between a cross-section immediately after the application step, wherein the fibrous material has received the composition, and a cross-section immediately before the step of applying the composition, wherein the fibrous material has not received the foam, is comprised between 10% and 50%, [0468] the weight percentage per square meter variation of the sheet fibrous material, between said cross-section immediately before the step of applying the treatment composition and said cross-section immediately before the printing step, is comprised between 10% and 50%.
[0469] Controlling the quantity of the treatment composition can be performed by considering at least one of the following parameters: accumulation of the treatment composition at the initial contact area, the speed of the moving belt 2.
[0470] After the step of contacting the fibrous material with the belt, the second side T2 of the material T itself—opposite to the first side T1—is ink-printed, optionally by a digital print. De facto, the second side T2 of the treated fibrous material exiting the treating station and in contact with the belt 2 is printed. The printing step is performed on the second side T2 of the fibrous material placed on the operative section 3.
[0471] As hereinbefore described, the printing station 6 comprises at least one printing module 7 which, during the movement of the fibrous material T (operative condition of the conveyor belt 2), remains in a fixed position and prints on all a width of the fibrous material T. Plural printing modules 7 can be provided (for example from 3 to 10) parallelly positioned to each other astride the conveyor belt and consecutively placed along the advancement direction A: for example the printing heads of each module can be supplied by a respective ink in order to obtain any chromatic combination.
[0472] The step of moving the fibrous material T is preferably but in a non-limiting way performed continuously at a speed constantly greater than 0, particularly constantly comprised between 20 and 100 m/min, still more particularly comprised between 30 and m/min. The steps of applying the treatment composition and printing are performed in-line during the continuous movement of the fibrous material T.
[0473] Moreover, the process can comprise, after the printing step, a further treatment step, for example performed by the station 10, during which the treatment composition is applied on the second side T2 of the printed material T.
[0474] Moreover, the process can comprise one or more steps of drying the sheet fibrous material, for example by means of the station 16; particularly, the process can comprise a step of drying the fibrous material immediately exiting the pressure organ 5a: such drying step enables to dry the treated fibrous material before the printing step. Moreover, the process can comprise a second drying step performed after the printing step: the printed material exiting the station 6 is caused to pass through the drying station 16.
[0475] The process, according to the present invention, can further comprise a step of supplying the fibrous material T by means of the station 14. The supplying step enables to directly supply the fibrous material T towards the treating station 4.
[0476] The supplying step can be performed by unwinding a roll of the material T placed on a drum rotatively commanded by a motor. In a preferred but non-limiting embodiment of the invention, the process comprises the following steps: [0477] receiving, from a sensor, a signal regarding the movement of the conveyor belt 2, [0478] determining, as a function of said signal, a movement speed of the fibrous material T along the advancement direction A, [0479] as a function of the movement speed of the fibrous material T, commanding a predetermined rotation speed of the drum so that the speed of the conveyor belt 2 is synchronized with the rotation speed of the drum.
[0480] Moreover, the process can comprise a vaporizing step [0481] by the means of the vaporizer 15—performed after the step of printing the sheet fibrous material. The vaporizing step enables to perform a fixing treatment of the printing ink on the material T: the printed material is contained in an environment having a vapor at conditions of pressure and temperature suitable for ensuring to fix the ink to the fibers of the material.
[0482] Moreover, the process can comprise a step of drying the printed fibrous material. The drying step can be performed on the material exiting the belt 2 or on the material placed on the operative section of the conveyor belt 2. In a preferred but non-limiting embodiment of the invention, the drying step is performed immediately after the vaporizing step.
[0483] Moreover, the process comprises a step of gathering the printed material for example by the gathering station 17. The gathering step enables to bring together the printed material exiting the conveyor belt 2 for example around a gathering drum, for defining a roll of printed material, or as an alternative in a container for gathering the printed material as layers.