A versatile and efficient method for the permanent marking of polymer surfaces that combines inkjet deposition and near‐infrared (NIR) laser curing is investigated. The NIR laser treatment forces the ink particles to migrate into the upper layers of the polymer. This results in the fixation of a permanent grayscale image that can be applied to various polymers, such as polypropylene, which is widely used in industry but still difficult to mark. The physiochemical processes induced by laser curing are investigated by electronic and optical microscopy. The dependence of the thickness of the deposited ink and the laser power on the contrast of marking are also studied. A mechanism implying fast laser‐induced melting of the polymer surface followed by displacement of carbon nanoparticles by convection is proposed. Finally, a comparison of the aging properties of samples prepared by this process and standard UV ink is proposed to illustrate the interesting nature of this new polymer marking process. Integrating the ink under the surface of the polymer, as in a skin tattooing procedure, by laser curing is an efficient way to generate permanent images on polymer surfaces.

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激光聚合物纹身：一种在聚合物表面永久标记的多功能方法

研究了将喷墨沉积和近红外（NIR）激光固化相结合的一种通用且有效的聚合物表面永久标记方法。NIR激光处理迫使墨水颗粒迁移到聚合物的上层。这导致可以将永久灰度图像固定化，该图像可以应用于各种聚合物，例如聚丙烯，该聚合物在工业中广泛使用，但仍然难以标记。通过电子和光学显微镜研究了激光固化引起的物理化学过程。还研究了沉积墨水的厚度和激光功率对标记对比度的依赖性。提出了一种机制，该机制暗示快速激光诱导的聚合物表面熔融，然后通过对流置换碳纳米颗粒。最后，建议比较此方法和标准UV墨水制备的样品的老化性能，以说明这种新的聚合物标记方法的有趣性质。如在皮肤纹身程序中那样，通过激光固化将油墨整合到聚合物表面下是在聚合物表面上产生永久图像的有效方法。