[Solved]-How to remove tick lines from secondary y axis in highcharts heatmap graph-Highcharts

actually, those lines are grid lines and an axis line (the one in the bottom). you can disable them by setting their width to 0.

xaxis: {
 linewidth: 0 
 ...
},

yaxis: {
 gridlinewidth: 0,
 ...
}

example: http://jsfiddle.net/sebdom/39xbu/390/