Funkcionalni model procesa izrade fotopolimerne tiskovne forme

doctoral thesis

• Title (english): Functional model of photopolymer printing plate production process
• Author: Tamara Tomašegović
• Mentor: Sanja Mahović Poljaček (mentor)
• Committee member: Branka Lozo (član povjerenstva)
• Committee member: Lidija Mandić (član povjerenstva)
• Committee member: Mirela Leskovac (član povjerenstva)
• Committee member: Sonja Jamnicki (član povjerenstva)
• Committee member: Sanja Martinez (član povjerenstva)
• Granter: University of Zagreb; Faculty of Graphic Arts; Zagreb
• Defense date and country: 2016-3-22, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Graphic Technology
• Universal decimal classification (UDC): 655 - Graphic industries. Printing. Publishing. Book trade

Abstract

Analiza utjecaja UVA i UVC post-ekspozicija u procesu izrade fotopolimerne tiskovne forme

za fleksotisak u ovom doktorskom radu provedena je pomoću različitih metoda mjerenja i

analize. Fotopolimerni uzorci korišteni u ovom istraživanju bili su Computer to Plate (CtP)

Laser Ablation Mask Layer (LAMS) tiskovne forme za fleksotisak sa vodenim i solventnim

razvijanjem. Analiza njihovih kemijskih, toplinskih, mehaničkih i površinskih svojstava

provedena je s ciljem definiranja i kvantificiranja utjecaja procesa post-ekspozicije na tiskovnu

formu i otisak dobiven pomoću tiskovnih formi s varijacijama u post-ekspozciji.

Kemijske promjene u materijalu uzrokovane UV post-ekspozicijom analizirane su pomoću

Fourier transform infracrvene spektroskopije – postupkom prigušene totalne refleksije,

energijski razlučujuće/disperzivne rentgenske spektrometrije i metode bubrenja. Toplinska

analize (diferencijalna pretražna kalorimetrija i termogravimetrijska analiza) prikazale su

utjecaj trajanja UVA i UVC post-ekspozicija na toplinsku stabilnost i razgradnju materijala.

Mehanička analiza dala je podatke o promjenama u tvrdoći tiskovne forme tijekom različitih

vremena post-ekspozicije. Površinska svojstva fotopolimernog materijala analizirana su

pomoću izračuna polarne i disperzne faze slobodne površinske energije te parametra hrapavosti.

Dobiveni rezultati su integrirani putem korelacije, kao i robusne metode najmanjih kvadrata i

modeliranja neuronskom mrežom kako bi se definirao funkcionalni model procesa izrade

tiskovne forme u odnosu na parametre koji utječu na definiciju njenih površinskih svojstava.

Otisci dobiveni modificiranim tiskovnim formama pokazali su značajne promjene u debljini

nanosa bojila, gustoći zacrnjenja, pokrivenosti površine svjetlih i tamnih tonova te deformaciji

tankih linija.

Rezultati dobiveni u ovom istraživanju dokazali su da se UVA i UVC post-ekspozicije u

procesu izrade tiskovnih formi za fleksotisak mogu koristiti kao jednostavan i brz alat za

modifikaciju svojstava njihove površine. Ova modifikacija može se koristiti za prilagodbu

površinskih svojstava tiskovne forme specifičnim zahtjevima, odnosno stvaranje

“personalizirang” fleksotiskarskog reprodukcijskog sustava za posebne primjene u

konvencionalnom i funkcionalnom tisku.

Abstract (english)

Characterization of the effects of UVA and UVC exposures in the post-treatment process of

photopolymer flexographic printing plate production was performed by various measurementand-

analysis methods. Samples used in this research were solvent-washable and waterwashable

Computer to Plate (CtP), Laser Ablation Mask Layer (LAMS) flexographic printing

plates. Analysis of the chemical, thermal, mechanical and surface properties of photopolymer

samples was performed in order to define and quantify the influence of the post-treatment

process on the properties of printing plates and corresponding prints. Chemical changes in the

material were analysed by means of Fourier transform infrared spectroscopy – attenuated total

reflectance method, energy dispersive X-ray spectroscopy and swelling experiments. Thermal

analysis (differential scanning calorimetry and thermogravimetric analysis) displayed the

influence of the duration of post-treatments on the thermal stability and degradation process of

the material, as well as the influence on the crosslinking completion. Mechanical analysis

provided the information about the changes in hardness of the printing plate due to the posttreatment

process. Surface properties of the photopolymer printing plate samples were analysed

by calculating the components of surface free energy and roughness parameters. Obtained

results were integrated via correlations, as well as least squares fitting and neural network

modelling in order to define the functional model of flexographic printing plate production in

relation to influencing parameters in the definition of printing plate’s properties in the

reproduction process. Prints obtained by UVA and UVC post-treated printing plates displayed

significant changes in ink layer thickness and the deformation of fine lines on the prints, as well

as the changes in optical density and surface coverage in low and high coverage areas.

Results obtained in this research proved that UVA and UVC exposures in the post-treatment

process of flexographic printing plate production can be used as a simple and quick tool for

modification of the properties of photopolymer material. This modification is useful in

adjusting printing plate’s surface and mechanical properties to a specific value, therefore

tailoring the flexographic reproduction system for specific applications in conventional and

functional printing.

• Keywords: fleksotisak; fotopolimerni materijal; UV post-ekspoziija; umrežavanje; površinska svojstva; funkcionalni tisak
• Keywords (english): flexography; photopolymer material; UV post-treatment; crosslinking; surface properties; functional printing
• Language: croatian
• URN:NBN: urn:nbn:hr:216:488088
• Study programme: Title: Graphic engineering and graphic product design; Course: Graphic technology; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti u području tehničkih znanosti (doktor/doktorica znanosti u području tehničkih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-04-24 22:05:15