One of two types of photopolymer plates used in flexographyin contrast to a sheet photopolymer. A liquid photopolymer plate is made by placing the negative of the image to be engraved emulsion-side-up on the exposure unit, covered by a transparent sheet.
A motorized roller evenly and uniformly spreads a liquid photopolymeric resin on top of the transparent cover sheet. It also adds a substrate sheet—or plate base—on top of the polymer, which has been treated to adhere to the liquid photopolymer. The liquid photopolymer is enhanced by exposing the base side of the plate to ultraviolet light, hardening the photopolymer on the reverse side of the plate.
Increasing or decreasing the exposure time varies the depth of penetration into the photopolymer of the radiation which varies the ultimate relief height of the plate.
For example, the longer the exposure, the deeper the penetration, and the shallower the floor of the plate. A second exposure to UV light from below i. The non-image areas are left unexposed, soft and soluble. The exposed plate is removed from the exposure unit, and the cover film peeled from the exposed plate surface. The exposed plate is then sent to a washout unit which removes the unhardened photopolymer from the plate surface, leaving the exposed image areas in relief.
In some cases, the plates can be pre-washed by hand using a squeegee or an automated device to remove the unexposed photopolymer and allow it to be reused.
This process is called resin reclaim. A mild detergent is applied to the plate in a washout unit to remove any residual unhardened resin. A final exposure to UV light further hardens the plate surface. Although liquid photopolymer plates are amber-colored which is more effective for UV light transmissionit is sometimes desirable to dye the plates prior to mounting, which may aid in proofing, inspection, and mounting. Any water-soluble fabric or industrial dye can be used on flexographic plates.
Some liquid photopolymer plates, called capped plate s, are processed using two layers of differently-formulated photopolymers, which vary several plate characteristics, such as hardness, resilience, and image geometry, from the raised image areas to the plate floor.
The advantages of capped plates include deeper reverse etch depth, less distortion, and wider impression latitude. The composition of the liquid photopolymer can either be oil and water resistant or solvent resistant.
The latter are the more compatible with highly volatile alcohol- or acetate-based solvent inks. Front Page Title Index. Liquid Photopolymer. All text and images are licensed under a Creative Commons License permitting sharing and adaptation with attribution. See Copyrights for details.The flexographic industry has many photopolymer choices from which to choose today. With advancements in photopolymer technology and the many additional options by which to process these plates, the choices are more varied than ever before.
Since a user would likely choose between liquid or sheet photopolymer in either a corrugated or multi-wall bag application, we will focus our comparison on these markets. In many cases when printing on corrugated board, low-density poly, or woven poly materials with water-based ink, liquid photopolymer is the plate of choice.
This is also the case in corrugated applications when the printing cylinder undercut requirement dictates a. In most instances, there does not seem to be an appreciable difference in the print result of liquid versus sheet with the parameters outlined above.
Sheet photopolymer plates are quite versatile and many different varieties have been manufactured to meet specific market needs.
There are sheet plates that are specifically compatible with water, solvent, or UV inks, and there is most likely a plate that will print well on paper, poly, film, and foil. Sheet photopolymer plates have been the industry standard for high-quality flexo printing in the narrow and wide-web markets, as well as some corrugated markets.
Liquid photopolymer plates have set the industry standard in the corrugated and multi-wall bag arenas due to their flexibility. There are some major differences when comparing production of liquid versus sheet photopolymer plates. While the same basic steps are followed exposure, washout, drying, and post-exposurethe technique and equipment used to handle these steps is quite different.
The major difference between the two production processes has to do with the way in which the polymer is prepared for exposure.
With liquid, the photopolymer resin is extruded from a positive displacement pump over a protective transparent film that covers or protects the negative. From there, the material is exposed similar to a sheet plate, with back exposure to establish the floor and face exposure that creates the actual printing image. The same basic steps are followed with respect to washout, drying, and germicidal treatment. It has produced improved reproduction with both halftone and line work and has also shown some success in regards to sharper imaging in the areas of shoulder relief.
This resin combination of a relatively hard durometer with the cap resin, and considerably softer durometer of the base resin, helps to minimize dot growth during impression. The cap thickness is typically no more than. Production Time.Polpatty vs liquid photopolymer
These are all factors to consider when choosing the right plate type for your printing application. Both sheet and liquid photopolymers can provide numerous benefits to the plate-maker and final print user when the right material is selected for the job. For more information, including registration for this free webinar, visit our Webinar page.
Liquid vs. Sheet Photopolymer … Which Is Best? Liquid Photopolymer In many cases when printing on corrugated board, low-density poly, or woven poly materials with water-based ink, liquid photopolymer is the plate of choice.
Liquid Plates Components used in the washout process consist of a water-based detergent, defoamer, and developer. Any unexposed resin can be reclaimed and used again if mixed properly with virgin resin. This equates to a minimal waste factor in material. This process is required when creating I-Plates or In-Position plates. Mounting can be eliminated with various digital workflows available today.
Is this accurate? Should this be: Mounting times can be drastically reduced with various digital workflows available today. Digital workflows allow images to be ganged in imposition style, as opposed to requiring the full glass for one job. The liquid platemaking room does not require the stringent mandates in terms of air exchange that is normally associated with solvents used to process sheet plates.Our liquid photopolymer resins are formulated to deliver optimum elasticity, resilience, hardness and ink transfer.
Download Brochure. Ideal for the multi-wall bag industry. Provides excellent print results on both paper and poly bags. Specifically formulated for corrugated applications and is a highly resilient, durable plate that provides excellent ink transfer. The perfect solution for stamps where consistent and crisp ink transfer is needed. The clarity and overall UV stability with this resin is unmatched in the industry today. Excellent results where hardness and clear definition of character is required.
AVMaster AVM liquid photopolymer is specifically formulated for molding applications, and is a highly resistant, durable plate that provides excellent imaging characteristics. Liquid Photopolymer.
Learn More. Provides excellent print results on both paper Designed to produce high-quality, high-density film negatives and positives. A solvent resistant, black, IR — UV absorbing coating on an optically clear polyester base. Handling Characteristics Laser Point Thermal Please wait while you are redirected to the right pageA popular use of liquid photopolymers is in making of rubber stamps.
Photoresists are used to make integrated circuits, flat panel displays, printed circuits, chemically milled parts, MEMS microelectromechanical systems etc. Similar liquid compositions can also be used for non-imaging applications such as adhesives, coatings and inks. Photopolymer formulations comprise of polymers, oligomers, monomers and additives. Polymer bases for photopolymers include acrylics, polyvinyl alcohol, polyvinyl cinnamate, polyisoprene, polyamides, epoxies, polyimides, styrenic block copolymers, nitrile rubber etc.
They may be used along with oligomers, monomers and additives. Polymers usually function as binders and determine processing characteristics as well as final physical properties of cured photopolymer compositions. Liquid compositions such as those used for printing plates and stereolithographic resins usually do not incorporate polymers as a significant component.
However, liquid photoresists may contain a polymer dissolved in a solvent carrier. The first photopolymers developed and marketed were based on polyvinyl cinnamates and sensitizers dissolved in solvents and marketed as photoresists by Eastman Kodak Company. A printing system has four independent components: a press, an image carrier, ink and paper or other substrates to carry a message.
The image carrier is the printing plate in traditional printing processes. The processes in which photopolymer plates are used to carry ink and transfer it to the substrate are lithography, flexography, letterpress and gravure. Read More. Stereolithography is an imaging process in three dimensions. Some synonyms used for stereolithography include 3D printing, optical fabrication, photosolidification, solid freeform fabrication, solid imaging, optical shaping, steric polymerization, desk-top manufacturing, additive manufacturing, electron beam melting, digital part materialization, freeforming etc.
Photoresists are photosensitive materials which after photoimaging and subsequent processing, resist action of certain chemicals in desired areas. They are basically of two types. In negative photoresists, light-exposed areas become less soluble as a result of photopolymerization, leaving behind, after etching and stripping of the resist, opaque features on a clear background.
All you wanted to know about. A complete guide for your reference on. What are Photopolymers? Printing Plates A printing system has four independent components: a press, an image carrier, ink and paper or other substrates to carry a message. Photoresists Photoresists are photosensitive materials which after photoimaging and subsequent processing, resist action of certain chemicals in desired areas.A printing system has four independent components: a press, an image carrier, ink and paper or other substrates to carry a message.
The image carrier is the printing plate in traditional printing processes. The processes in which photopolymer plates are used to carry ink and transfer it to the substrate are lithography, flexography, letterpress and gravure. Lithographic plates are planographic plates which are also known as offset plates.
Photopolymer-based litho plates mainly compete with diazo plates. Here photopolymer plates have replaced stereotypes and metal plates. On dry offset plates, also called letterset plates, an intermediate blanket cylinder is used to transfer the image to the substrate. Flexographic plates are similar to letterpress plates except the image career is elastomeric. Photopolymers have replaced the bulk of rubber-based flexo plates. Below is the list of various Manufacturers:.
Screen Printing Products. Printing Plates A printing system has four independent components: a press, an image carrier, ink and paper or other substrates to carry a message.Goregaon East, Mumbai No.
Mumbai, Maharashtra. Mumbai No. Paharganj, Delhi No. Railway Station, Paharganj, Delhi -Delhi. Kolkata, West Bengal. Surat, Gujarat. Bhuj, Kutch, Dist. Kachchh Factory Plot No. Kachchh, Gujarat. Verified Supplier. Thane, Maharashtra. Andheri East, Mumbai Unit No. Kolhapur, Maharashtra. Nehru Nagar West, Coimbatore No. Coimbatore, Tamil Nadu.
Delhi 37, Chawri Bazar, Delhi -Delhi. Mumbai Vasai East, Mumbai -Dist. Pimpri Colony, Pune Shop No.
Pune, Maharashtra. Verified Supplier Company Video. Have a requirement? Get Best Price.
The photo in photopolymer denotes its sensitivity to light. A photopolymer is kept in a liquid state prior to use. Upon exposure to light, the photopolymer transforms into a solid state.
The light, or actinic radiationcan be emitted from a laser or a lamp. Compounds that become solid upon exposure to a certain radiation are known as radiation-curable; a photopolymer will only cure under light, but other compounds may be similarly sensitive to microwave or heat radiation. Typically, a photopolymer consists of a complex mixture of compounds, rather than a single element.
One common use of the photopolymer is stereolithographya three-dimensional printing process that fabricates a solid object from a computer image. Photopolymer is used in conjunction with this process to make stamps, as it is less expensive than real rubber.
This is achieved with a metal plate coated with photopolymer film and an impression or print of the desired image on a transparent surface. The photopolymer plate and image are exposed together in light, usually ultraviolet. Photopolymer is also used to print type and art. A printing plate made of photopolymer can be used in a letterpress, and also has some advantages over traditional lead or magnesium plates. Photopolymer plates are easier to design than metal.
In addition, they require less maintenance, they are more environmentally friendly because they are not etched with acids, and their surface is resistant to abrasion and therefore will not wear down - making for a longer useable life and more consistent type.
A consumer can use computer design software to set type, as well as incorporate any images or artwork, and then send a scan to a professional platemaker. Photopolymer products are also used to make photoresistswhich are patterned impressions such as those on a circuit board.
These photoresists are used in applications such as flat panel displays, printed or integrated circuitsand microelectromechanical systems. A photopolymer product can also be used to make considerably larger models, as in rapid prototyping.
Rapid prototyping is the automated building of a prototype from a three-dimensional drawing. A three-dimensional CAD drawing is loaded onto a computer and optically scanned, and an ultraviolet laser beam solidifies two-dimensional sections of photopolymer liquid in a vat according to instructions from the computer.