Aramids etching

As far as we know, apart from a preliminary report about mercerization of cotton fibers (3) and a recent paper about chemically etched PETP filaments (4), high modulus aramide fibers and carbon fibers are practically the only systems with detailed (recently) published work on electron diffraction and dark field of ultrathin sections of textile or paratextile fibers (5, 6,... 

Aramid tire cords have been treated by argon plasma etching and plasma polymerization of acetylene. The combination of argon plasma etching and acetylene plasma polymerization results in a greatly improved pull-out force of 91 N in comparison to 34 N with the untreated aramid tire cord. Thus, the plasma treatment improves the adhesion to rubber compounds. " ... 

H. M. Kang, T. H. Yoon, and W. J. Van Ooij. Enhanced adhesion of aramid tire cords via argon plasma etching and acetylene plasma polymerization. J. 

Carbon fibres are frequently subjected to an oxidative etching process to improve adhesion, but a size is sometimes used (see Fibre-matrix adhesion - carbon fibres). Sizing is generally ineffective with aramid fibres because of lack of susceptible sites, but plasma deposition of amine groups is said to improve adhesion. 

The etching study was conducted to complement ultrathin sectioning of high modulus oriented fibers [238]. Representative results of the plasma etching experiment are shown in the secondary electron images (SEI) (Fig. 4.19% Glass fibers and amorphous polyester film were used as controls. Oriented PET and aramid fibers were etched for 15 min in argon in order to evaluate the effect of the treatment on oriented crystaUine... 

Fig. 4.19 SEI images show the result of plasma etching with argon (A) a glass fiber surface shows no ordered details (B) amorphous PET film with particles but no order (C) an orient crystalline PET fiber surface with lateral striations, and (D) an aramid surface also with lateral striations. The effect of plasma etching with oxygen is shown for a glass fiber surface (E) which reveals no detail and (F) an aramid fiber which exWbits a lateral striated texture.

Fig. 4.20 SEI shows the effect of argon ion etching on an aramid fiber surface where lateral striations are observed normal to the fiber axis.

Aramid-reinforced laminate and prepreg allow fast microvia hole formation and at the same time maintain the performance characteristic of a smooth surface for fine-line conductor imaging. The ablation speed of non-woven (aramid) laminates and prepregs is close to that achieved when using nonreinforced materials such as resin-coated foil, dry film, or liquid dielectrics. Since aramid laminates are very stable, they allow the fabrication of doublesided, very thin, etched innerlayers, which are then pressed to a multilayer package in a single... 

ALIVH. The ALIVH (Any Layer Interstitial Via Hole) process has been in development for many years by Matsushita Components of Osaka, Japan. The novel process eliminates additive metallization and plating, but defines all features by subtractive etching of the copper foil. The build-up process is not sequential, though it uses layer pairs and aramid-epoxy prepreg with copper-paste vias that can be laminated at one time into a three-dimensional structure. CMK (the second largest PCB maker in the world) and other Japanese firms have licensed the process. Six to 10 layers have been laminated in this way. 

Etching has been used to reveal structures in polymer fibers [179,180], polymer blends [181,182] and in bulk polymers, such as PET [183] and PE [184]. Periodic structures were seen to develop on argon plasma etched, oriented materials, such as nylon and PET, thought to be characteristic of the fold period [185]. Such structures were also shown for ion etched (argon) fibers [186]. Fine scale structures were observed for etched polyamide [187], PET [19,188] and aramid fibers [187] which showed ripple structures transverse to the fiber axis. 

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