PENGARUH JENIS SOLVENT TERHADAP KARAKTERISTIK KUALITAS CETAK TINTA PADA FILM OPP (ORIENTED POLYPROPYLENE)

ABSTRAK
Industri kemasan fleksibel memerlukan tinta cetak yang mampu menghasilkan kualitas cetak tinggi sekaligus memenuhi persyaratan keamanan pangan. Pemilihan solvent yang kurang tepat dapat menyebabkan viskositas tidak stabil, penurunan
daya lekat, dan tingginya residu pelarut pada kemasan. Penelitian ini bertujuan menganalisis pengaruh jenis solvent terhadap karakteristik tinta cetak berbasis PVC pada media Oriented Polypropylene (OPP) serta menentukan solvent yang paling optimal. Solvent yang diuji meliputi Ethyl Acetate (EA), Isopropyl Alcohol (IPA), Methyl Ethyl Ketone (MEK), dan Toluene (TOL), dengan komposisi resin, pigmen, dan aditif yang dibuat tetap. Pengujian meliputi viskositas, drying time, density, gloss, adhesion, blocking, dan kadar residu pelarut menggunakan Gas Chromatography (GC). Data dianalisis menggunakan nilai rata-rata dan standar deviasi. Hasil penelitian menunjukkan bahwa jenis solvent berpengaruh terhadap karakteristik tinta. EA menghasilkan viskositas rendah, kualitas cetak yang baik, serta kadar residu pelarut paling rendah sehingga lebih sesuai untuk kemasan pangan. IPA memiliki viskositas tertinggi dan waktu pengeringan paling lama. MEK memberikan performa yang cukup stabil, sedangkan Toluene menghasilkan daya lekat yang baik tetapi memiliki residu pelarut tertinggi. Berdasarkan seluruh parameter pengujian, EA merupakan solvent paling optimal karena memberikan keseimbangan antara kualitas cetak, kestabilan tinta, dan keamanan kemasan pangan sesuai prinsip regulasi bahan kontak pangan.
Kata kunci: solvent, tinta cetak, OPP, kualitas cetak, Gas Chromatography.
ABSTRACT
The flexible packaging industry requires printing inks that provide high print quality while complying with food safety requirements. Inappropriate solvent selection may lead to unstable viscosity, poor adhesion, and high residual solvent
levels. This study investigated the effect of solvent type on the properties of PVC based printing ink applied to Oriented Polypropylene (OPP) film and identified the
optimum solvent. Four solvents were evaluated: Ethyl Acetate (EA), Isopropyl Alcohol (IPA), Methyl Ethyl Ketone (MEK), and Toluene (TOL), while the resin, pigment, and additive compositions were kept constant. The ink formulations were
evaluated through viscosity, drying time, density, gloss, adhesion, blocking, and residual solvent analysis using Gas Chromatography (GC). Data were analyzed using mean and standard deviation. The results showed that solvent type
significantly influenced ink performance. EA produced low viscosity, good print quality, and the lowest residual solvent content, making it the most suitable solvent
for food packaging applications. IPA showed the highest viscosity and the slowest drying time. MEK demonstrated relatively stable performance, whereas Toluene provided good adhesion but the highest residual solvent content. Overall, EA was identified as the optimum solvent because it offered the best balance between print quality, ink stability, and food packaging safety in accordance with food-contact
material safety principles.
Keywords: solvent, printing ink, OPP film, print quality, Gas Chromatography.